newsletter i /2019...microencapsulation of porous solids filled with various actives (capsule core)...

Newsletter I /2019

Encapsulation of Solid Materials

Newsletter I/2019 © Fraunhofer IAP © Fraunhofer ICT

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0. TPM members’ corner ............................................................................................................... 3

I . In Focus: “Encapsulation of solid materials” .......................................................................... 4

Introduction ......................................................................................................................... 4

Patent evaluation ................................................................................................................ 6

I.2.1 Search strategy ................................................................................................................. 6 I.2.2 Evaluation of patents ........................................................................................................ 7 I.2.3 Patent highlights............................................................................................................. 11 I.2.4 Summary ........................................................................................................................ 13

Academic literature evaluation .........................................................................................14

I.3.1 Search strategy and statistics .......................................................................................... 14 I.3.2 Evaluation of academic literature .................................................................................... 16 I.3.3 Interesting concepts presented in academic literature ..................................................... 21 I.3.4 Literature ........................................................................................................................ 21

I I . Information platforms and interesting news .............................................................23

Regularly updated information platforms ........................................................................23

Interesting news, projects and publications ....................................................................23

II.2.1 Interesting news and projects ......................................................................................... 23 II.2.2 New publications ............................................................................................................ 24

II.2.2.1 Smart Textile Coatings and Laminates..................................................................... 24 II.2.2.2 Nano-Biopesticides Today and Future Perspectives .................................................. 24 II.2.2.3 Recommendations for a Definition and Categorization Framework for Plastic Debris 25 II.2.2.4 Technology Impact Analysis for Micro- and Nano-encapsulation ............................. 26

Upcoming events ..............................................................................................................27

Contents


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(1) TPM Calendar 2019

Literature and patent updates: calendar week 10, 18, 27, 36, 45 / 2019; 2 / 2020

Newsletters: calendar week 17, 37, 51 / 2019

TPM Meeting: 24th of October 2019 (location: Fraunhofer Institute for Manufacturing

Technology and Advanced Materials IFAM / Bremen)

TPM workshop 2019: 24th of October 2019 (location: Fraunhofer Institute for

Manufacturing Technology and Advanced Materials IFAM / Bremen)

Preparation of TPM round 2020/21: autumn 2019

(2) Newsletter Topics 2018-2019

Ranking Topic Release

1 Trends in microencapsulation 2017/18 updated published

2 Microcapsules for paint applications published

3 Microencapsulation for personal care applications published

4 Encapsulation of solid materials this newsletter

5 Microencapsulation for agrochemical ca. KW37/2019

6 Microcapsules for textile applications ca. KW51/2019

(3) TPM Homepage

The homepage is online: http://www.platform-microencapsulation.fraunhofer.de

Some TPM members have offered to present their activities in the field of microencapsulation

on the homepage. Currently we are preparing a template. We will provide you with

further information soon.

Furthermore, please send us your proposals regarding the content of the homepage.

(4) Information on TPM Workshop 2019

Topic: Biodegradable microparticles and microcapsules

Date: 24th of October 2019 (Pls. save the date)

Location: Fraunhofer Institute for Manufacturing Technology and Advanced Materials

IFAM in Bremen / Germany

Information on registration and submission of contributions can be found in the flyer (available

on the TPM platform and homepage). We will inform you about the final program in July 2019.

A short internal meeting of the TPM members is planned before the start of the workshop

(about 9.00-9.45 h).

0. TPM members’ corner

http://www.platform-microencapsulation.fraunhofer.de/


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The microencapsulation of liquids is comparatively unproblematic if relevant material data such as solubility, pH and temperature stability are known. In contrast, the encapsulation of solid particles is a more challenging process, especially if capsules with high content of solid material are the goal. In this case only coating or deposition techniques can be used, since phase separation of the wall materials during the capsule formation step cannot be utilized in case of solid substances. When it is possible, physical processes such as fluidized bed coating are applied for the encapsulation of solid particles. A disadvantage of coating processes is the use of high amounts of (often organic) solvents. In addition, particles in a size range below ca. 100 μm can´t be coated due to the limitations of the possible hydrodynamic regimes. Another problem related to the encapsulation of solid particles is their complex hydrodynamic behavior, especially if they have irregular shapes. In coating processes high flow velocities and fluidic swirls develop at exposed points of the solid materials (needle points, sharp edges on crystals, pore structures). Coating materials that deposit at these positions can be quickly removed again and precipitate separately. A reduction in the flow velocity is usually not possible, since then agglomeration effects can occur. Nevertheless, there are a number of possibilities for the effective encapsulation of solid particles. The microencapsulation of solids has already been the subject of a newsletter (NL 2_2010). The current newsletter is,therefore dedicated in particular to new / improved encapsulation methods and new fields of application from 2011 onwards. A short summary of the information given in NL_2010 is provided below (in italics): Examples of commercialized microencapsulated solids: - Writing/printing/recording: pigments, fillers (compatibilization between filler and

binder) - Agriculture and forestry: pesticides, fertilizers (controlled release, reduction of pesticide

toxicity) - Pharmaceutical appplications: drugs (controlled release, improvement of drug stability) - Food: acids, minerals (improvement of stability, masking of taste, odor) Relevant encapsulation processes: Besides polymerization, in situ polycondensation, coacervation and solvent evaporation/extraction/diffusion some relatively new microencapsulation technologies were described and applied: - miniemulsion polymerization - layer‐by‐layer technology - sol‐gel encapsulation - supercritical CO2‐assisted microencapsulation Identified approaches for further development: - elaboration of the new class of hybrid nanoparticles development of new concepts - development of new compatibilization techniques - much larger variety of morphologies with potential advantages over core‐shell‐type

particles (dissymmetrical particles, multilayer structures, more complex structures) - much larger variety of stimuli responsive polymeric and hybrid nanostructured particles Interesting future applications/application fields: - life science (colloidal supports for biodiagnostics) - microfluidics (lab‐on‐chip devices for fluid management)

I . In Focus: “Encapsulation of solid materials”

Introduction


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- nanotechnologies (colloidal templates for designing patterned surfaces in soft lithography techniques, macroporous materials issued from 3D colloidal crystals)

- nano‐based flame retardants

As a starting point for the current research, relevant publications of the TPM literature updates from January 2011 until February 2019 were evaluated. In less than 10% of all publications the core material is a solid. The following figures show the types of the solid core materials (Fig. 1) as well as the wall materials used for encapsulation (Fig. 2).

Fig. 1 Overview about types of microencapsulated solids

Most of the solid core materials are biocides and pesticides for application in agriculture, paints and coatings, followed by flame retardants for polymer processing and metal/metal oxide powders for various purposes. The wall materials are especially biopolymers and acrylate/styrene polymers or copolymers.

Fig. 2 Overview about applied of wall materials (PU/PUR = Polyurea and Polyurethane)

24%

24%

16%

13%

10%

13%

Biopolymers

Acrylate/Styrene Polymers& Copolymers

Silica

Amine/Phenolic resins

PU/PUR

Others


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I.2.1 Search strategy

Patent data are retrieved from PatBase (www.patbase.com). PatBase is a database which uses patent families as units. The patent family is defined as a collection of patents which have the same claims but are registered in different countries. This reduces the risk of counting the same inventions multiple times for patent statistics. The identification of patents, in which microencapsulated solids are described, was extremely difficult. Various variants of the combination of solid and microencapsulation and corresponding synonyms were tested. In all cases, there was only a small number of relevant matches. Therefore the patent search was finally carried out in all IPC subclasses relevant for microencapsulation (Search 1) using the search word combinations and limitations listed below (last retrieval 01.04.2019). The search was performed in the patent title (T), abstract (A) and claims (C).

Search 1: IC=(A01N25/28 or A61K8/11 or B01J13/00 or B01J13/02 or B01J13/04 or B01J13/06 or B01J13/08 or B01J13/10 or B01J13/12 or B01J13/14 or B01J13/16 or B01J13/18 or B01J13/20 or B01J13/22 or B41M5/165 or B41M5/28 or C01B32/372 or C12N15/88 or D06M23/12 or D21H21/54 or G02F1/1334) (Results 44754)

Search 2: 1 and EPR>2010 (Results 11156) Search 3: 2 and CC=(DE or US OR WO or EP) (Results 3799) Search 4: 3 and TAC=(pigment* or dye*) (Results 521) Search 5: 4 and IC=(b01J13*) (Results 196) Search 6: 3 and TAC=(metal oxid*) (Results 186) Search 7: 6 and IC=(b01J13*) (Results 122) Search 8: 3 and TAC=(salt hydrat*) (Results 9) Search 9: 3 and TAC=(flame retardant*) (Results 21) Search 10: 3 and TAC=(biocide* or pesticide*) (Results 182) Search 11: 10 and IC=b01j13* (Results 66) Search 12: 5 or 7 or 8 or 9 or 12 (Results 358) The 358 patents resulting from search 12 were evaluated in terms of technical details. Basically four variants of microencapsulated solids can be distinguished: 1. Microencapsulation of solids (capsule core) 2. Microencapsulation of solids dispersed in a carrier liquid (capsule core) 3. Microencapsulation of porous solids filled with various actives (capsule core) 4. Integration of solids (active ingredients) in the capsule wall In general double- and multi-core encapsulation could also referred as “solid encapsulation”, i.e. solid capsules are encapsulated with one or more additional shells. This is not considered in the NL. Detailed information about interesting patent applications (from our point of view) are provided in the following sections. In addition, the top 21 patent assignees by family are shown in Fig. 3. The top three assignees with ≥ 15 patent families are globally operating chemical companies DOW (now DowDuPont) and BASF as well as the global consumer goods manufacturer Procter & Gamble.

Patent evaluation


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Fig. 3 Top 21 patent assignees by family

I.2.2 Evaluation of patents

In the following Tables 1-4, details of relevant patents are summarized including information on the encapsulated solid, the shell material used for encapsulation as well as the encapsulation purpose / application field of the encapsulated solid. Because a categorization of the solid materials is difficult to perform (e.g. metal oxides can be categorized in pigment, catalyst etc.) the patents classification was made with regard to the used capsule shell materials.

Tab. 1 Inorganic capsule shell NP=nanoparticle, MIC=microcap sule green highlighted: core=solid particle dispersion (particles in a carrier fluid) yellow highlighted: porous solid core with ad-/absorbed actives blue highlighted: solid particles in the shell

Patent number Assignee

Core material Shell material / encapsulation process

Application

DE102012202069 FRAUNHOFER GES FORSCHUNG [DE]

Sulphur Inorganic, preferably siliceous materials (silicic acid polycondensates, eg produced from silicatic sols, or from silicic acid salts such as sodium silicate)

Crosslinking agent for rubber MICs size: 0.05-200 µm

DE102015103126 SCHILL + SEILACHER STRUKTOL GMBH [DE]

Sulphur Siliceous materials (sodium silicate, silica sol) + silicone resin

Crosslinking agent for rubber


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Application

WO2018003670 ADEKA CORP [JP]

Ultraviolet radiation absorber (e.g. benzotriazole-based)

Silica-based (TEOS) Cosmetics (skin protection)

WO2019011975 SEB SA [FR]

Thermochromic semiconductor such as bismuth oxide, pigments

1st (inner) shell: mineral material or an organo-mineral hybrid material 2nd (outer) shell: mineral material or an organo-mineral hybrid material, different from that of the inner layer

Temperature indicator, in particular in a culinary article (semiconducting metal oxides are easily reducible to hot contact with oil or lipids and the compounds formed after this reduction reaction are no longer thermochromic MICs size: 1-500 µm (d50)

Tab. 2 (Modified) Natural polymer capsule shell NP=nanoparticle, MIC=microcapsule green highlighted: core=solid particle dispersion (particles in a carrier fluid) yellow highlighted: porous solid core with ad-/absorbed actives blue highlighted: solid particles in the shell



Application

WO2012156965 TAGRA BIOTECHNOLOGIES LTD [IL]

Black pigment (carbon black, black iron oxide, or a mixture thereof)

Poly(meth)acrylate, cellulose ether or ester, or a combination thereof (solvent extraction)

Cosmetic formulations (e.g. mascara or eye liner) MICs size: 1-2 µm

WO2013056782 GIESECKE & DEVRIENT GMBH [DE]

Transparent (preferably hydrophobic) carrier liquid such as mineral oil, and a plurality of magnetic opaque pigments (metal oxide pigments, preferably iron oxide pigments)

Complex coacervation Gelatin/gum arabic

Microcapsule whose translucency is reversibly intensifiable by applying an external magnetic field for security elements MICs size: 5-80 µm

WO2016170531 BOTANOCAP LTD [IL] See I.2.3

Porous solid material in which an essential oil is absorbed essential oil derivatives in a solid form

Interpolymeric complex formation, with subsequently further cross-linking with at least one multivalent cationic moiety

Disinfectant, pesticide, insect repellant, antiviral and/or antifungal applications MICs size: < 500 nm

WO2018232075 E INK CORP [US]

Electrically charged particles (pigments) dispersed in a non-polar solvent

Complex of pig gelatin and acacia

Improved variable transmission devices containing electro-optic media, e.g. as coatings on windows


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Application

(minimization of “haze”, reduction of grain) MICs size: 60% 50-90 μm at least 15% 20-49 μm

Tab. 3 Acrylate-based capsule shell NP=nanoparticle, MIC=microcapsule green highlighted: core=solid particle dispersion (particles in a carrier fluid) yellow highlighted: porous solid core with ad-/absorbed actives blue highlighted: solid particles in the shell



Application

US2010255309 APPLETON PAPER INC [US], ENCAPSYS LLC [US]

Anionic, cationic, or neutral but polar solid particles such as powdered sugar, calcined clay, fumaric acid

Amine acrylate or methacrylate based / interfacial reaction in an oil continuous phase

Coating of solid hydrophilic core materials

WO2012156965 TAGRA BIOTECHNOLOGIES LTD [IL]

Black pigment (carbon black, black iron oxide, or a mixture thereof)

Poly(meth)acrylate, cellulose ether or ester, or a combination thereof (solvent extraction)

Cosmetic formulations (e.g. mascara or eye liner) MICs size: 1-2 µm

WO2013054030 ARKEMA FRANCE [FR]

Inorganic pigment particles such as titanium dioxide, hematite, cadmium red, chromium oxide, copper silicate, carbon black, magnetit

Dispersion polymerization in an organic medium the electrostatically A chargeable functional monomer is selected to charge the particle positively (vinylpyridine, dimethylaminomethacrylate, or another monomers having a chargeable amine moiety of pKa greater than 5) or negatively (acrylic or methacrylic acid or its derivatives)

Electrophoretic display devices MICs size: 0.5-2 µm

WO2014204747 WO2014204754 APPVION INC [US]

Titanium dioxide, carbonates, clays, and combinations thereof

Poly(meth)acrylate, polystyrene, melamine formaldehyde, urea formaldehyde, polyvinyl alcohol, polyvinyl acetate, and combinations thereof

Reduction in the agglomeration of the particles, an improvement of the particles' compatibility with the dispersing medium, and an improvement in the light stability of the particles in paper coating applications or paints

WO2014007836 IHNFELDT ROBIN [US]

Metal or metal oxide porous abrasive particles such as fumed or colloidal silica or alumina, ceria, TiO2 etc.

Polyacrylate, polymethacrylate, polyethyleneglycol, poly-L-lysine, poly-vinyl alcohol, polysaccharides, polyethylene, polypropylene, poly-vinyl

Planarizing and/or polishing wafer surfaces


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Application

pores can be impregnated with a chemical payload (e.g. a water soluble complexing agent)

acetate, polyisoprene, and/or any combination thereof, poly(N-isopropylacrylamide) or poly(N-isopropylmethacrylamide).

WO2018162615 CONSTRUCTION RESEARCH & TECH GMBH [DE]

Catalysts (e.g. organic metal salts) The polyaddition catalyst is released by a chemical stimulus, e.g. upon contact with polyols or water.

(Meth)Acrylic copolymer/ radical polymerization

Catalyzing polyaddition reactions (polyurea / urethane) for the fixing of components in the construction and manufacturing industry MICs size: 1-50 µm (d50)

Tab. 4 Organic capsule shell (except acrylate -based capsule shells, comp. Tab. 3) NP=nanoparticle, MIC=microcapsule green highlighted: core=solid particle dispersion (particles in a carrier fluid) yellow highlighted: porous solid core with ad-/absorbed actives blue highlighted: solid particles in the shell



Application

WO2013170934 WO2013170937 WO2013170938 MERCK PATENT GMBH [DE]

Pigment core particles (such as titanium dioxide in the rutile, anatase, or amorphous modification)

Polymer comprising monomer units of at least one polymerisable dye, at least one co-monomer, at least one polymerisable steric stabiliser, optionally at least one charged co-monomer, and optionally at least one crosslinking co-monomer (dispersion polymerization)

Reflective coloured particles and electrophoretic fluids and displays comprising such reflective coloured particles improved electrophoretic fluids and coloured polymer particles

WO2013016087 DOW GLOBAL TECHNOLOGIES LLC [US]; ROHM & HAAS [US]

Non-pigment inorganic particles (diameter 0.005-5 µm) such as alumina or silica

Water-soluble sulfur acid-functional first polymer which comprises at least two amine moieties and a second copolymerized unit bearing at least one acid-functional monomer (emulsion polymerization in the presence of the dispersed inorganic particles)

Coating compositions (inks, paper coatings, architectural coatings etc.)

WO2017037210 BASF AGRO BV [NL]

Saflufenacil (highly active herbicide)

Aminoplast (in situ polymerization)

Efficiently growth inhibition of undesirable vegetation at low application rates D50: 2-10 µm D90: < 30 µm


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Application

US10179846B THE UNIV OF TULSA [US] See I.2.3

Magnetic NP (iron oxide) with silica shell, redispersed in liquid self-healing polymer

Various, especially urea-formaldehyde resin

Self-healing / guiding magnetic MICs

WO2018193083 BASF COLORS & EFFECTS GMBH [DE] See I.2.3

Organic pigment particle diameter d(v 0.9) to below 1500 nm (by milling of an aqueous suspension in presence of a polymer dispersant)

Aminoplast resin Paint formulations efficiently preparing aqueous dispersions of pigments / microencapsulated pigments having a small average particle size MICs size: d(v 0.9)< 1.5 µm

WO2018189588 RHODIA OPERATIONS [FR]; CENTRE NAT RECH SCIENT [FR]

Hollow or non-hollow (hydrophobic liquid core)

Rigid (comprising silicone dioxide) or flexible shell (typically a homopolymer or copolymer derived from ethylenically-unsaturated monomers) with embedded metallic NP free of transition metal oxide (typically gold or silver). Each metallic nanoparticle comprises an organic capping agent, typically a polyvinylpyrrolidone, more typically poly(diallyldimethylammonium-nitrate-co-1 -vinylpyrrolidone).

Controllable optical sensors

I.2.3 Patent highlights

WO2016170531 BOTANOCAP LTD [IL] Microcapsules are made of starting materials classified as non-toxic and generally recognized as safe (GRAS) and environmentally friendly. Core materials are essential oils specified as follows: (a) liquid essential oil (b) solid essential oil derivative (c) porous solid material in which an essential oil is absorbed (up to 60 % of the porous

solid core material such as aerogel/silica) The shell formation is initiated by interpolymeric complex formation of at least (1) one first (natural) polymer being a polyacid (alginic acid, agaropectin, alginate, carboxymethyl cellulose, chondroitin sulfate, heparin, polyacrylic acid, pectin, polygalacturonic acid, starch carboxylic acid, xanthan gum, and combinations and/or derivatives thereof) (2) one second (synthetic) polymer (polyethylene glycol (PEG), polypropylene glycol (PPG), polyethylene oxide (PEO), polypropylene oxide (PPO) polyvinylpyrrolidone (PVP), and homo- and co-polymers thereof) (3) the interpolymeric complex is cross-linked with at least one multivalent cationic moiety See also: WO2010018576 BOTANOCAP LTD [IL]:


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This patent claims an essential oil mixed with a porous solid material (aerogel/silica such as Aerosil, Cab-O-Sil etc.) and coated by a layer of polyurea, polyurethane, an amphiphilic shell composed of a multivalent salt form of alkanoic acid and additionally by a fatty layer (waxes, fats, fatty acids, lipids, low melting polymers).

The following applications are considered:

Preventing and/or treating bacterial infections and/or fungal infections in harvested crops and/or in products prone to develop said infections

Preventing and/or treating pesticidal infestation in animals; and/or for repelling pests in an environment; and/or for treating water bodies containing at least one water pest

Impregnation of plastic products (veterinary, household outdoor products).

US10179846B THE UNIV OF TULSA [US] Over the past 15 years, materials have been developed with the capability to self-repair (self-healing materials). There are several mechanisms that can be used to achieve self-healing functionality. One approach is to sequester a liquid “healing agent” in a material that can be delivered to autonomically repair damaged regions. Many microcapsule-based self-healing materials are synthesized by simply mixing in microcapsules into a host polymer before it cures. The microcapsules serve as both storage and trigger of the healing response. While microcapsules enable self-healing functionality, the inclusion of microcapsules in polymeric materials can alter material properties in several ways. Typically, as microcapsule concentration increases, fracture toughness increases. Therefore, in order to minimize the negative impact on material properties, it is desirable to develop techniques for optimizing concentration of the microcapsules in order to minimize cost and any negative impact on material properties. One possible approach for mitigating negative impacts is to guide microcapsules to locations that have been identified as regions of high failure probability. This guiding can be accomplished using magnetic fields in a manner similar to targeted drug delivery methods being developed in biomedicine. In the invention of the university of Tulsa, magnetic particles are used to alter the self-healing performance of a material. Here the magnetic particles serve as the active material that allows self-healing components to be assembled into structures that were previously not possible. This required the development of a novel type of magnetic microcapsule containing magnetic particles suspended in a liquid core. This is different from other “encapsulated” nanoparticles where the particle is a solid core with a solid shell. The presence of these magnetic particles in the liquid core allows the accurate manipulation of the microcapsule location within the material using magnetic fields. WO2018193083 BASF COLORS & EFFECTS GMBH [DE] The invention relates to a process for preparing aqueous dispersions of pigment particles, which contain a pigment and an aminoplast resin which surrounds or embeds the pigment. Pigments usually consist of solid particles (about 0.02 to 2 μm size). The pigment particles tend to have a strong affinity for each other and, unless stabilized, tend to clump together and form large agglomerates. Agglomeration is a serious problem for such pigments because surface area increases with the decrease of the particle size and consequently, surface tension and the tendency to agglomerate increases. Thus, acceptable dispersions of small particle pigments typically will normally require an inordinate amount of resinous grind vehicle and/or pigment dispersant to effect de-agglomeration and to prevent subsequent re-agglomeration. The presence of such high levels of resinous grind vehicles and pigment dispersants, however, can be detrimental to the resultant coating.


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The inventors propose a tailor-made encapsulation process to solve these problems. They propose to perform the polycondensation of an aminoplast pre-condensate in the aqueous suspension after or during a pigment milling step in the presence of a polymer dispersant. Polymeric dispersants are in particular selected from non-ionic polymers having a polyurethane

backbone, where the polyoxyalkylene groups form part of the backbone or side chains, and non-ionic

polymers having a carbon-backbone, where the polyoxyalkylene groups are present as side chains.

The stable aqueous dispersions of pigments are useful for tinting waterborne liquid coating compositions.

I.2.4 Summary

In principle, the number of patents, which focus on the microencapsulation of solids, is rather

low. Completely new approaches to encapsulate solid particles are missing. Relevant patents

reflect improvements of established processes such as radical polymerization, in situ

polymerization etc. Encapsulated solids are in particular small pigment particles (organic or

inorganic; natural or synthetic). Reasons for encapsulation are:

Prevention of agglomeration (because of the big surface of the small particles)

Protection from environmental influences (e.g. UV radiation, pH of media)

Improvement of storage, color stability & durability

Encapsulation processes, types of solid particles and application fields are summarized in Table

5.

Tab. 5 Summary of encapsulation processes, types of solid particles and applic ation fields

Capsule shell Purpose of encapsulation Application

Inorganic (mostly sol-gel processes)

Pigments Sulphur

Cosmetics (skin protection) Temperature indication Rubber crosslinking

Natural polymers (solvent extraction, complex coacervation)

Pigments Cosmetics Electronics & Optics (Security elements, electro-optic media) Agriculture and surfaces (disinfection / repellent / pesticide)

(Meth)Acrylates (radical polymerization)

Pigments Catalysts

Cosmetics (Paper) coatings Electronics & Optics (electrophoretic displays, wafer surfaces) Construction & Manufacturing

Organic (mostly amino resins / in situ polymerization)

Pigments Non-pigment particles Pesticides Magnetic nanoparticles

Electronics & Optics (Electrophoretic fluids, optical sensors) Coatings Agriculture Self-healing Paint formulations


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I.3.1 Search strategy and statistics

The search strategy was hard to decide upon (the same as in the case of patents), since looking for the “solid active ingredient” does not make any sense. Thus, the strategy was to try to find some keywords that might be relevant in this case, identify the most interesting substance classes for the encapsulation and look within each class of substances separately (the same as in case of patents). We started with the following search phrase in Web of Knowledge: ALL=(suspension polymerization OR emulsion polymerization OR interfacial polymerization OR coating OR deposition) AND ALL=(capsul* OR microcapsul* OR encapsulat* OR microencapsulat* OR core-shell OR multicompartment OR matrix) NOT ALL=(fragrance OR phase change material OR PCM OR liquid core OR liquid-filled OR paraffin OR oil OR oil-filled OR nanorod* OR nanowire) This search gives about 25.000 hits. Analysis of statistics shows that overall number of publications is gradually increasing each year (in accordance with the growth of total number of publications per year). Although, the field seems to be growing slower in the last 5 years compared to 5 years ago, as shown in Fig. 4.

Fig. 4 Statistics: Number of academic publications per year found via search phrase shown above

Analyzing by category in Web of Knowledge shows that most of the articles belong to the field of material science, interdisciplinary chemistry and nanoscience (Fig. 5).

Academic literature evaluation


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Fig. 5 Statistics: Number of academic publications belonging to various categories/fields of knowledge

Analysis by organization and funding shows rather expected, but somewhat peculiar result: most of the publications come from China followed by USA. Even Max-Planck society shares the very small portion of the academic publication “market” (Fig. 6, 7).

Fig. 6 Statistics: Number of academic publications originating from various organizations. China is the absolute leader, followed by France and USA.


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Fig. 7 Statistics: Number of academic publications originating from various country. Here the leading position of China is even more visible .

I.3.2 Evaluation of academic literature

Most of the academic publications found via this strategy describes preparation of nanosized capsules and composite particles. The concepts and chemistry used for the preparation of the nanosized objects is, however, not very different form the concepts already demonstrated in the past for the production of microcapsules and microparticles. The quintessence of most of the publications is that nanosized capsules can be formed and analyzed with respect to their structure and composition. As before, most of the publication deal only with preparation and analysis of capsules, while application tests (estimation of stability in various mediums and release tests) are mostly out of scope of academic literature. Biocides When looking for publications devoted to the encapsulation of biocides, it was identified that many new publications are dealing not with encapsulation and controlled release of biocides, but with detection and absorption of biocides in the food formulations as well as drinking and processing waters. The corresponding publications are described in subsections “sensors” and “absorbers”. In addition, many concepts related to the development of environmentally friendly, bio-based and/or less toxic biocidal formulations are presented. It seems that academic community slowly starts to be aware of accumulation of toxic low molecular weight substances in the environment and is looking for new solutions. Also, concepts related to the increase of the biocide efficiency and reduction of biocide consumption without compromising the efficiency are described. One of the related strategies is release on demand, which usually implies integration of mechanisms, which can switch the biocidal efficiency on and off. Interesting illustration of how microencapsulation can increase efficiency of biocides was presented in [1]. A novel delivery technique involving the encapsulation of a toxin within hundred micron-sized particles, edible for the bivalves, has been recently proposed. This strategy exploits the mussels' filtration activity and minimises their avoidance responses to certain chemicals, resulting in an increase of their susceptibility to the biocide. The effectiveness of the product as a molluscicide has been demonstrated in laboratory bioassays. Encapsulation was observed to reduce the amount of biocide required to achieve 90% mortality in a 12-h treatment by a factor of approximately three. Another interesting approach related to the encapsulation of solid particles but not really utilizing the core materials themselves was demonstrated in [2]. Microcapsules consisting of


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alternating layers of oppositely charged poly(phenylene ethynylene)-type conjugated polyelectrolytes (CPEs) were prepared via layer-by-layer deposition onto MnCO3 template particles followed by dissolution of the template particles using an ethylenediaminetetraacetate solution. The resulting microcapsules exhibit bright-green fluorescence emission characteristics of the CPEs. Strong antimicrobial activity was observed upon mixing of polyelectrolyte capsules with Cobetia marina or Pseudomonas aeruginosa followed by white-light irradiation. It was demonstrated that the materials act as highly effective light-activated micro "Roach Motels" with greater than 95% kill after exposure to similar to 1h of white light. In [3] copper nanoparticles surrounded with silica layers were suggested as an alternative for the organic biocides to tackle their “low heat resistance and short lifetime”. Long-time release of copper ions has been demonstrated. Polyimide-copper layers consisting of individual capsule-like splats were one-step fabricated in [4] by solution precursor flame spray through controlling the reaction between dianhydride and diamine dissolved in copper nanoparticles-containing dimethylformamide solvent (Fig. 8). Antifouling performances of the constructed layers were assessed by examining colonization behaviors of typical bacteria Bacillus sp. and marine algae Phaeodactylum tricornutum and Chlorella on their surfaces. The liquid flame spray route and the encapsulated structure of the polyimide-Cu coatings are expected to open a new window for designing and constructing environment-friendly marine antifouling layers for long-term applications.

Fig. 8 The principle of coating formulation and preparation described in [4]

Corrosion inhibitors Corrosion protection mostly deals with encapsulation of various inhibitors in nanocapsules. Along with nonoscience, the main trends are all-biobased/biodegradable paints and application of corresponding encapsulation materials. Another trend, as in case of biocides, is development of less toxic and more environmentally friendly solutions, free of classical corrosion inhibitors, which are known to accumulate in the environment. In [5] a commonly used corrosion inhibitor 2-mercaptobenzothiazole (MBT), was nanoencapsulated in polylactic acid (PLA) nanoparticles produced via nanoprecipitation method. [6] presents a new method to prepare poly(sodium acrylate) magnetite composite nanoparticles.

Core/shell type magnetite nanocomposites were synthesized using sodium acrylate as monomer and N,N-methylenebisacrylamide (MBA) as crosslinker. Microemulsion polymerization was used for constructing core/shell structures with magnetite nanoparticles as core and poly(sodium acrylate) as shell.

Flame retardants For flame retardants, the situation is not different: nanoscaled capsules prepared via application of well-known chemistry and using more elaborated polymerization techniques is described. In [7] a novel and versatile route for fabricating flame-retardant microcapsules via microfluidics technology was reported. The flame-retardant microcapsules were prepared with a dimethyl methylphosphonate (DMMP) core and an ultraviolet-curable (UV-curable) polysiloxane shell.


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Microsized particles are also sometimes studied. In this case the novelty is in demonstrating the performance of the developed materials by integration into the products and demonstration of property advantages in case of encapsulated products. However, this kind of publications is rare, this field of knowledge is much more present in the patent literature. In [8], microencapsulated ammonium polyphosphate with melamine formaldehyde resin (MFAPP) was prepared and applied in intumescent fire-retardant coatings to solve the problems mentioned. Even immersed in distilled water for 12h, the coatings containing MFAPP did not show obvious damage, indicating microencapsulation improved the water resistance of coatings. Pigments Encapsulation of pigments was identified as the most fast developing and interesting field of solid material encapsulation. Pigments are nanosized/submicronsized particles and the main challenge solved by encapsulation is to prevent agglomeration and improve stability of pigments in various mediums. Various coating techniques leading to the nanometer-sized coatings around each pigment particle are discussed. In some cases the protective power of the corresponding coating is also estimated. [9] describes a combination of sol-gel method and in situ polymerization to form a hybrid

silica/poly(acrylic acid) nanolayer for the corrosion protection of aluminum pigments. The quality of the coating was tested by immersing the pigments into acidic and basic mediums. The hybrid coating seem to have good barrier properties. Similar approach was used in [10], where aluminum pigments were first coated with sol-gel film by using tetraethoxysilane (TEOS) and vinyltriethoxysilane (VTES) as the precursor, followed by free radical copolymerization of styrene (St), divinylbenzene (DVB) and maleic acid anhydride (MAA) with the vinyl group of the VTES. It was found that both the TEOS-and-VTES-coated (TV-coated) and the TEOS-VTES-St-DVB-MAA- coated (TVSDM-coated) aluminum pigments were superior in the stability test over the uncoated aluminum pigments and TVSDM-based procedure leads to better corrosion resistance.

Fig. 9 The time dependence of the hydrogen formation in alkaline aqueous media at pH 11 for different samples. (1 - non-encapsulated, 4,8 - encapsulated in different ways)

New interesting strategies for the individual particle coating are also presented. In [11] an Polymer-encapsulated phthalocyanine blue pigment dispersion was prepared with a polymerizable dispersant by emulsion polymerization method. The surface-active initiators ensure that initiation of the polymerization reactions happens directly on the pigment particle surface. The structures of used initiators are shown below. Similar approach was used in [12].


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Fig. 10 Polymerizable dispersants used in [11]

In [13] novel core-shell latices with a partially crosslinked hydrophilic polymer core and a hard hydrophobic shell of polystyrene were prepared to improve optical properties of coated paper such as gloss and brightness. These core-shell latices were prepared by sequential addition of a monomer mixture of styrene, n-butylacrylate and methacrylic acid. Introducing a new polymerizable optical brightener, i.e., 1-[(4-vinylphenoxy)-methyl]-4-(2-phenylethylenyl)benzene allowed for further improvement of the optical properties. The results demonstrated that by optimizing polymer composition one can significantly enhance the optical properties and surface smoothness of coated paper.

Mechanical impact modifiers Impact modifiers are core-shell particles, which are used as the additive to plastic in order to modify its’ mechanical characteristics. Typically, the core consists of soft rubbery polymer (which is able to absorb mechanical stress) and a solid glassy shell (which prevents the softening of overall material). The challenge can be therefore formulated as encapsulation of soft particles in hard shells. Many polymerization approaches leading to the particles with the desired morphology have been described. As in other fields, the academic publications almost exclusively deal with the nanosised particles. Thus, in [14] polystyrene and poly(butyl acrylate) (PBA) grafted on a crosslinked styrene-co-butadiene core was synthesized by emulsion polymerization. Few years later, three-layer core-shell structural nanoparticles, poly styrene/polybutadiene/poly (methyl methacrylate) (PSBM) were synthesized [15] by the same group via emulsion graft polymerization method. The toughening efficiency of PSBM in PVC was compared with MBS (methyl methacrylate-butadiene-styrene copolymer). Similar concept (methyl acrylate/butyl-acrylate) was applied in [16] for toughening of PLA. Tensile testing showed the maximum elongation at break of 279.9% when ACR content reached 20 wt%, which was a 65-fold increase compared with neat PLA. In [17] similar approach has been realized by utilizing an emulsion grafting polymerization in polybutadiene-graft-polystyrene system using a redox initiator system. In this article it was shown that bigger particles (above 300 nm) are more efficient than the smaller ones (about 100 nm).

Absorbers Absorbers are mostly developed for the extraction of toxic (biocides, drugs, heavy metals) or valuable molecules (dyes) from waters and other formulations. Very often some porous particles with a chosen surface chemistry, which allows for the fixation of toxic molecules from a medium, are developed. Further, these particles can be coated with an additional polymer or hydrogel layer in order to improve their stability and overall performance. Magnetic nano/microparticles are typically built-in in order to allow for easy removal of loaded particles. Novel smart polystyrene-poly(N-isopropylmethacrylamide-acrylic acid) [PSt@p(NIPMAM-Aac] core/shell gel particles were prepared [18] by two step precipitation polymerization method and used as adsorbent for removal of heavy metal ions such as Pb(II), Cu(II), Cd(II) and Cr(III) from aqueous medium. The application of green adsorbents from renewable biomass for dye wastewater treatment has been described in [19]. In this work novel lignin-based Fe3O4@lignosulfonate/phenolic core-shell micro spheres were fabricated for the first time to remove cationic dyes from aqueous solutions.


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Results showed that lignosulfonate/phenolic shell coated uniformly on the Fe3O4 core to form a well-defined core-shell microsphere. Overall, the results indicate that the novel Fe3O4@lignosulfonate/phenolic microspheres offer a great potential for removing cationic dyes from wastewater in practical applications. For the extraction of nitrophenol from water, another solution has been elaborated in [20]. Magnetic porous MOF-containing composites, Fe3O4-PSS@ZIF-67 (PSS, poly (sodium-p-styrenesulfonate)), were prepared. The obtained composites exhibit core-shell structure, for which the spherical Fe3O4 particles as core are embedded in ZIF-67 shell. The existence of SO3-

anions on poly (sodium-p-styrenesulfonate) is the key factor for the uniform coating of ZIF-67 on Fe3O4 particles. [21] synthesized core-shell microcapsule absorbents with cPAA (cross-linked poly(acrylic acid))

as the core and PSMA (poly(styrene-alt-maleic anhydride)) as the shell by precipitation polymerization, where the shell served to delay the absorption of excess water in cement mortars.

Sensors

Sensors are often based on the specific interactions between certain molecules, which lead to predictable changes of properties. The more specific the interactions are, the better sensor one can generally create. Therefore, biological systems, known for very high selectivity, are often utilized. Enzymes offer a solid platform for this kind of interactions and often utilized for the development of new kind of sensors. The right assembly and establishment of the right type of connectivity within one sensing particles and between the sensing particle and the carrying substrate is very important in this field of research. In [22], a novel biomolecule immobilization approach has been proposed to the synthesis of multi-functional core-shell glucose oxidase-Au-polydopamine-Fe3O4 magnetic bionanoparticles (GOx-Au-PDA-Fe3O4 MBNPs) using the one-pot chemical polymerization method. Then, a high performance biosensor has been constructed by effectively attaching the proposed GOx-Au-PDA-Fe3O4 MBNPs to the surface of the magnetic glassy carbon electrode. The resultant GOx-Au-PDA-Fe3O4 MBNPs not only have the magnetism of Fe3O4 nanoparticles which makes them easily manipulated by an external magnetic field, but also have the excellent biocompatibility of PDA to maintain the native structure of the GOx, and good conductivity of Au nanoparticles which can facilitate the direct electrochemistry of GOx in the biofilm. Hence, the present GOx-Au-PDA-Fe3O4 biofilm displays good linear amperometric response to glucose concentration ranging from 0.02 to 1.875 mM.

Living cells

Living cells are encapsulated with various purposes. Sometimes encapsulation is necessary for the protection of probiotic bacteria necessary for their direct delivery to the intestine [23]. In some cases, the motivation is to produce cell-based sensors. In this case the goal of encapsulation is rather to achieve certain connectivity between the microorganism surface and the surrounding material in order to be able to transmit the information. New materials, such as metal-organic frameworks (MOFs) have been shown promising as the encapsulating materials. In [24] MOFs were utilizes as a new interesting encapsulating material. A yeast@ZIF-8 core-shell composite material was successfully synthesized under room temperature in aqueous solution. The ZIF-8 shell endowed the inner yeast cells with a considerably extended lifetime without any nutrients at 4 degrees C. Compared with the bare yeast cells, most coated yeast cells were kept alive even when cultured in zymolyase solution for 3 h. Furthermore, the encapsulated yeast cells could be reactivated and regrown by dissolving the ZIF-8 shell with competitive coordination interactions.


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I.3.3 Interesting concepts presented in academic literature

An interesting concept for the surface-initiated polymerization was presented in [25]. Horseradish peroxidase was used as the catalyst for the oxidation of diketones grafted on the surfaces of silica nanoparticles. Hydrogen peroxide was used as the oxidizing agent to start the oxidation of the diketones producing radicals, which start the polymerization reaction of acrylamide resulting in polyacrylamide brushes grafted to the silica nanoparticle (Fig. 11).

Fig. 11 Surface-initiated enzyme-assisted polymerization of acrylamide

I.3.4 Literature

1. Costa, R., D.C. Aldridge, and G.D. Moggridge, Preparation and evaluation of biocide-loaded particles to control the biofouling zebra mussel, Dreissena polymorpha. Chemical Engineering Research & Design, 2011. 89(11A): p. 2322-2329.

2. Corbitt, T.S., et al., Conjugated Polyelectrolyte Capsules: Light-Activated Antimicrobial Micro "Roach Motels". Acs Applied Materials & Interfaces, 2009. 1(1): p. 48-52.

3. Bae, J.H., J.M. Cha, and B.K. Ryu, Production of Cu@SiO2 Core-Shell Nanoparticles with Antibacterial Properties. Journal of Nanoscience and Nanotechnology, 2019. 19(3): p. 1690-1694.

4. Liu, Y., et al., Developing polyimide-copper antifouling coatings with capsule structures for sustainable release of copper. Materials & Design, 2017. 130: p. 285-293.

5. Alrashed, M.M., S. Jana, and M.D. Soucek, Corrosion performance of polyurethane hybrid coatings with encapsulated inhibitor. Progress in Organic Coatings, 2019. 130: p. 235-243.

6. Atta, A.M., et al., Preparation and Application of Crosslinked Poly(sodium acrylate)-Coated Magnetite Nanoparticles as Corrosion Inhibitors for Carbon Steel Alloy. Molecules, 2015. 20(1): p. 1244-1261.

7. Kang, F.R., et al., Microfluidic fabrication of polysiloxane/dimethyl methylphosphonate flame-retardant microcapsule and its application in silicone foams. Polymers for Advanced Technologies, 2019. 30(5): p. 1269-1278.

8. Liu, Z.T., et al., Effect of microencapsulated ammonium polyphosphate on the durability and fire resistance of waterborne intumescent fire-retardant coatings. Journal of Coatings Technology and Research, 2019. 16(1): p. 135-145.

9. Amirshaqaqi, N., M. Salami-Kalajahi, and M. Mahdavian, Encapsulation of aluminum flakes with hybrid silica/poly(acrylic acid) nanolayers by combination of sol-gel and in situ polymerization methods: a corrosion behavior study. Journal of Sol-Gel Science and Technology, 2014. 69(3): p. 513-519.

10. Li, L.J., et al., Aluminum pigments encapsulated by inorganic-organic hybrid coatings and their stability in alkaline aqueous media. Journal of Coatings Technology and Research, 2008. 5(1): p. 77-83.

11. Fu, S.H., et al., Preparation and properties of polymer-encapsulated phthalocyanine blue pigment via emulsion polymerization. Progress in Organic Coatings, 2012. 73(2-3): p. 149-154.


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12. Fu, S.H., et al., Preparation of Core-Shell Latex for the Pigmented Ink of Textile Inkjet Printing. Journal of Applied Polymer Science, 2013. 127(4): p. 2678-2683.

13. Koskinen, M. and C.E. Wilen, Preparation of Core-Shell Latexes for Paper Coatings. Journal of Applied Polymer Science, 2009. 112(3): p. 1265-1270.

14. Chen, M., et al., Core-shell particles designed for toughening poly(vinyl chloride). Polymer International, 2010. 59(7): p. 980-985.

15. Chen, M., et al., Toughening Poly (Vinyl Chloride) by PS/PB/PMMA Three-Layer Particles. Polymer-Plastics Technology and Engineering, 2013. 52(8): p. 814-819.

16. Chen, Y., et al., Core-shell nanoparticles toughened polylactide with excellent transparency and stiffness-toughness balance. Composites Science and Technology, 2018. 164: p. 168-177.

17. Deng, Y.J., et al., Co-toughened Polystyrene by Submicrometer-Sized Core-Shell Rubber Particles and Micrometer-Sized Salami Rubber Particles. Industrial & Engineering Chemistry Research, 2013. 52(14): p. 5079-5084.

18. Naseem, K., et al., Adsorptive removal of heavy metal ions using polystyrene-poly(N-isopropylmethacrylamide-acrylic acid) core/shell gel particles: Adsorption isotherms and kinetic study. Journal of Molecular Liquids, 2019. 277: p. 522-531.

19. Wang, G.H., et al., Novel Fe3O4@lignosulfonate/phenolic core-shell microspheres for highly efficient removal of cationic dyes from aqueous solution. Industrial Crops and Products, 2019. 127: p. 110-118.

20. Yang, Q.X., et al., Magnetic beads embedded in poly (sodium-p-styrenesulfonate) and ZIF-67: Removal of nitrophenol from water. Journal of Solid State Chemistry, 2018. 265: p. 200-207.

21. Hwang, K. and K. Ha, Synthesis and characterization of cross-linked poly(acrylic acid)-poly(styrene-alt-maleic anhydride) core-shell microcapsule absorbents for cement mortar. Korean Journal of Chemical Engineering, 2014. 31(5): p. 911-917.

22. Peng, H.P., et al., Facile preparation of novel core-shell enzyme-Au-polydopamine-Fe3O4 magnetic bionanoparticles for glucose sensor. Biosensors & Bioelectronics, 2013. 42: p. 293-299.

23. Azarkhavarani, P.R., E. Ziaee, and S.M.H. Hosseini, Effect of encapsulation on the stability and survivability of Enterococcus faecium in a non-dairy probiotic beverage. Food Science and Technology International, 2019. 25(3): p. 233-242.

24. Sun, C., et al., Encapsulation of live cells by metal-organic frameworks for viability protection. Science China-Materials, 2019. 62(6): p. 885-891.

25. Fukushima, H., et al., Surface-initiated enzymatic vinyl polymerization: synthesis of polymer-grafted silica particles using horseradish peroxidase as catalyst. Polymer Chemistry, 2012. 3(5): p. 1123-1125.


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http://bioencapsulation.net/ (Homepage of the Bioencapsulation Research Group BRG, with

Newsletters, Conference and workshop calendar and more – not only in the field of

bioencapsulation!)

http://nanoparticles.org/ (“The information resource for particle technology”)

http://www.specialchem4cosmetics.com (search term “microencapsulation” or similar

especially new patents in the cosmetic field)

http://www.specialchem4polymers.com (search term “microencapsulation” or similar

especially new patents in chemistry)

http://www.alibaba.com (search term “microencapsulation” or similar products, suppliers and

prices)

http://www.scirp.org/journal/jeas/ (open-access Journal of Encapsulation and Adsorption

Sciences (JEAS) launched in 2011 scientific and technological advances that cover basic

sciences, engineering aspects and applied technology of molecules encapsulation and

adsorption.

http://www.chemeurope.com/en/microencapsulation.html

Microencapsulation services, videos, white papers, events, publications in the field of

microencapsulation

II.2.1 Interesting news and projects

Devan Joins Project to Recycle Coated and Painted Textile and Plastic Materials DECOAT

EU-funded project, Devan as a key partner, started in February 2019 The project consortium, led by Belgian R&D center CENTEXBEL, consists of 17 European partners from across the value chain including design, manufacturing, NGOs, and research and innovation. The focus of the consortium is on coated and painted textiles and plastic materials which are currently not recyclable. DECOAT has been established to investigate triggerable smart polymer material systems and appropriate recycling processes. The solutions will be based on smart additives (like microcapsules or microwave triggered additives) that will enable the efficient of coatings and other finishes, activated by a specific trigger (heat, humidity, microwave, chemical) to permit recycling. Devan’s specific role is in the development of microcapsules that will release its active core on application of a certain trigger (e.g. heat) at the end of life of the article. This active core material may be something that, for example, will promote the detachment of different coating layers (by separating them), opening the possibility for recyclability/re-use of the base materials. Different active core ingredients will be evaluated, and Devan will develop processes for each type of core ingredient and for each type of coating layer/matrix.

I I . Information platforms and interesting news

Regularly updated information platforms

Interesting news, projects and publications

http://bioencapsulation.net/

http://nanoparticles.org/

http://www.specialchem4cosmetics.com/

http://www.specialchem4polymers.com/

http://www.alibaba.com/

http://www.scirp.org/journal/jeas/

http://www.chemeurope.com/en/microencapsulation.html


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The bold aim of the four-year project is to decrease landfill by 75% of coated articles that are presently difficult to recycle, such as clothing, electronic goods and automotive components. DECOAT is expected to generate in the medium term a new market valued at over 150 million Euros in Europe.

II.2.2 New publications

II.2.2.1 Smart Textile Coatings and Laminates

Smart Textile Coatings and Laminates A volume in The Textile Institute Book Series Woodhead Publishing • 2nd Edition • 2019 ISBN 978-0-08-102428-7

Description Smart Textile Coatings and Laminates, Second Edition, reviews a variety of topics regarding textile coatings and laminates to provide a stimulus for developing new and improved textile products. It addresses coating and laminating processes and techniques and base fabrics and their interaction in coated fabrics. Other sections discuss the different types of smart and intelligent coatings and laminates, including microencapsulation technology, conductive coatings, breathable coatings, phase change materials and their applications in textiles. Many new chapters have been added in this updated edition, including the medical applications of smart coatings, responsive coatings, and the integration of electronics into textiles.

II.2.2.2 Nano-Biopesticides Today and Future Perspectives

Nano-Biopesticides Today and Future Perspectives Edited by Opender Koul Academic Press 2019

ISBN 978-0-12-815829-6


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Description Nano-Biopesticides Today and Future Perspectives "is the first single-volume resource to examine the practical development, implementation and implications of combining the environmentally aware use of biopesticides with the potential power of nanotechnology. While biopesticides have been utilized for years, researchers have only recently begun exploring delivery methods that utilize nanotechnology to increase efficacy while limiting the negative impacts traditionally seen through the use of pest control means. Written by a panel of global experts, the book provides a foundation on nano-biopesticide development paths, plant health and nutrition, formulation and means of delivery."

II.2.2.3 Recommendations for a Definition and Categorization Framework for Plastic Debris

Are We Speaking the Same Language? Recommendations for a Definition and Categorization Framework for Plastic Debris N.B. Hartmann et al. Environ. Sci. Technol., 2019, 53 (3), pp 1039–1047 DOI: 10.1021/acs.est.8b05297

Description The accumulation of plastic litter in natural environments is a global issue. Concerns over potential negative impacts on the economy, wildlife, and human health provide strong incentives for improving the sustainable use of plastics. Despite the many voices raised on the issue, a consensus on how to define and categorize plastic debris does not exist. But this is evident for microplastics, where inconsistent size classes are used and where the materials to be included are under debate. An international author consortium critically discuss the advantages and disadvantages of a unified terminology, propose a definition and categorization framework, and highlight areas of uncertainty. Going beyond size classes, the framework includes physicochemical properties (polymer composition, solid state, solubility) as defining criteria and size, shape, color, and origin as classifiers for categorization (Fig. 12). Such a basis is fundamental for the standardization of analysis methods, the development of monitoring programs, but also for the comparability of effect studies.

Fig. 12. Proposed definition and categorization framework. Excl. = excluded


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II.2.2.4 Technology Impact Analysis for Micro- and Nano-encapsulation

Micro- and Nano-encapsulation: Technology Impact Analysis TechVision Group of Frost & Sullivan D87C-TV, published in December 2018

The research service titled, “Micro- and Nano-encapsulation – Technology Impact Analysis” analyzes the potential of the technology across various applications.

According to the authors, the research study provides:

An overview of various micro- and nano-encapsulation technologies.

A highlight of various application segments and trends that influence adoption.

An analysis of the key factors that influence adoption of micro- and nano-encapsulation amongst various industries.

An assessment of various technology developments and industry initiatives.

A patent filing trend analysis highlighting key patents, both granted and in application status related to micro- and nanoencapsulation

New developmental aspects and future prospects for development and adoption of micro- and nano-encapsulation technologies.

Micro- and nano-encapsulation technologies expected to find new application avenues in the next years are shown in Fig. 13.

Regulations play a vital role in the adoption of micro-and nano-encapsulation technologies, materials and end-products. Industry-specific and application specific standards and regulations differ from region to region and govern the adoption of a specific technology in a particular region. Not considering the healthcare industry, Europe is considered to a have the most stringent regulatory and standards approach, especially in personal care, F&B and materials intended for followed the US. Bio-based Materials for Encapsulation are of significant focus among regulatory authorities (Fig. 14).

Figure 13. Micro- and nano-encapsulation technology development roadmap


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Figure 14. Regulations play a vital role in the adoption of micro -and nano-encapsulation technologies

Event: 22d Microencapsulation Industrial Convention

Date: June 3-6, 2019

Location: Zurich, Switzerland

Information: http://bioencapsulation.net/2019-Zurich-Microencapsulation-Industrial-

Convention/

Event: 26th International Conference on Bioencapsulation

Date: August 27-29, 2019

Location: Strasbourg, France

Information: http://bioencapsulation.net/2019_Strasbourg_International_

Conference_on_Bioencapsulation/

Event: Innovations in Encapsulation 2019

Date: December 13th, 2019

Location: London, U.K.

Information: https://www.formulation.org.uk/inen19-home.html

@ Disclaimer: No commercial use of these data is allowed, personal use of TPM-member only. If permission for public use or other use is necessary please contact the authors of this

study via [email protected] or [email protected].

Upcoming events

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http://bioencapsulation.net/2019_Strasbourg_International_

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