providing application benefits along the value...

SURFACTANTS FOR THE EMULSION POLYMERIZATION

Providing application benefits along the value chain

SURFACTANTS FOR THE EMULSION POLYMERIZATION2

1 Welcome to Clariant 2 General information on emulsion polymerization

Whatdocustomersvalue?

Technicalprinciplesofemulsionpolymerization

Emulsionpolymerizationprocess

Stabilizationofpolymerdispersions

Keyfunctionsoftheemulsifiers

3 Set up of the performance screening test for emulsifiers Ourapproach

Guiderecipesandtestparametersforthepolymeremulsions

Evaluationofphysicalpropertiesandstability

Evaluationofemulsioninapaintformulation

4 Test results on the performance of nonionic emulsifier Impactofnonionicemulsifieroncoagulumformationandparticlesize

Impactofnonionicemulsifieronstability

Overviewguideprocedures–nonionicemulsifier

5 Test results on the performance of anionic emulsifier Impactofanionicemulsifierinstyreneacrylicbinder

Impactofthestyreneacrylicbinderinpaintsandcolorants

Impactofanionicemulsifierinvinylacetatebinder

Impactofthevinylacetatebinderinpaintsandcolorants

Impactofanionicemulsifierinpureacrylicbinder

Impactofthepureacrylicbinderinpaintsandcolorants

Overviewguideprocedures–anionicemulsifier

6 Results and benefits at a glance

7 Starting recipes for further polymer dispersions Vinylacetateacrylicdispersionfortextilecoatings

Pureacrylicdispersionforpressuresensitiveadhesives

Styreneacrylatedispersionfortileadhesives

Hardstyreneacrylatedispersionforpapercoatings

Emulsionpropertiesoffurtherapplications

Table of Contents

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Welcome to Clariant 1

As a world leader in specialty chemicals, Clariant focuses on creating value by investing in future profi- table markets and sustainable growth. Clariant is headquartered in Muttenz near Basel, Switzerland with generated sales of more than CHF 6 billion in 2013. Clariant’s activities are divided into four business areas: Care Chemicals, Catalysis & Energy, Natural Resources and Plastics & Coatings. The business unit Industrial & Consumer Specialties (ICS) is part of the Care Chemicals, together with the operations of New Business Development and the future oriented Biotechnology R&D center.

Combining high-quality products with long term expertise, the business unit ICS delivers value added solutions to the emulsion polymer industry. We offer a broad range of surfactants to be used as emulsi-fiers in the emulsion polymerization process. Products from the EMULSOGEN®, GENAPOL®, HOSTAPUR®, HOSTAPHAT® and HOSTAPAL® series control the particle size and particle size distribution, improve electrolyte, freeze-thaw stability and reduce grid formation.

Our objective is helping our customers in meeting their customers’ requirements for performance, quality and regulatory compliance as well as the needs from the consumer market such as low odor, low VOC levels and favorable labeling.

Mt. HollyClear Lake

Santa Clara

Suzano

Tarragona

Frankfurt

ShizuokaDaya Bay

Tangerang

Zhenjiang

CoatzacoalcosMaracay

Gebze

Zarate

PRODUCTION SITES: 14• Clear Lake (TX, USA)

• Coatzacoalcos (Mexico)

• Daya Bay (China)

• Gendorf (Germany)

• Gebze (Turkey)

• Maracay (Venezuela)

• Mt. Holly (NC, USA)

• Santa Clara (Mexico)

• Shizuoka (Japan)

• Suzano (Brazil)

• Tangerang (Indonesia)

• Tarragona (Spain)

• Zarate (Argentina)

• Zhenjiang (China)

CLARIANT INNOVATION CENTER: 1• Frankfurt (Germany)

APPLICATION DEVELOPMENT CENTRES: 7• Gendorf (Germany)

• Mexico City (Mexico)

• Mt. Holly (USA)

• Shanghai (China)

• Shizuoka (Japan)

• Sao Paulo (Brazil)

• Thane (India)

Shanghai

Mexico City

Gendorf

Thane

Sao Paulo


Emulsion PolymerizationEMULSIFIERS FOR VINYL ACETATE, PURE ACRYLIC AND STYRENE ACRYLIC POLYMER EMULSIONS

5

WHAT DO CUSTOMERS VALUE?As a key supplier to the emulsion polymerization industry, we understand our customers’ needs. Clariant knows that the only guarantee of long-term success is to deliver consistent quality and stable properties.

To deliver performance solutions to the final polymer emulsion this requires a good knowledge of the value creation chain, thus a deep comprehension of our customers’ and their consumers’ problems and requirements.

There are a variety of attributes that are of high importance for the emulsion polymeriza-tion process and the final application.

For instance, manufacturers of latex dispersions expect components and raw materials to provide a range of properties, such as:n Easy handling n Safe use and low impact on the environment (favorable labeling)n High biodegradabilityn Global availability

Our products deliver all these, but we also understand that you need to achieve the desired performance of the emulsion in order to meet your own customers’ application requirements.

Our surfactants positively influence the dispersion properties and contribute significantly to the success of the formulation by providing benefits, such as:n Enable fast rate of polymerizationn Minimize coagulum or fouling in the reactorn High electrolyte stabilityn High shear stabilityn Increased storage life due to improved temperature adaptabilityn High compatibility with the final application

General information on emulsion polymerization

RAW MATERIAL SELECTION

Monomer

Surfactant Emulsifier

Water

Polymer dispersion

Dispersion powder

Spray drying Paints

Adhesives

Paper/paperboard coatings

Other (e.g. textile coatings, construction, etc)

END-APPLICATIONFORMULATION AND MANUFACTURING

Initiator

Monomer emulsion

Polymerization

Monomer Droplet

MicelleFormation

Polymerization

2


Owing to the versatility of the polymerization process, customized polymers for a wide range of applications can be synthesized. Thus emulsion polymers find use in varied appli-cations. Nevertheless, the market is closely linked to a relatively narrow group of products, most prominently water-based paints, paper/paperboard coatings and general purpose adhesives. The world emulsion polymer demand accounted for 11,910 kilo tons in 2013. Thereof the demand for water-based paints is approx. 4,730 kilo tons, being with 40% the highest share of the global emulsion polymers demand. In water-based paints the most commonly used types are acrylics and vinyl acetate, accounting together 91% or approx. 4,320 kilo tons.

Due to the variety of applications, the consumer requirements can range from high tinting strengths, low VOC and APEO free in decorative paints to enhanced durability and flame retardancy in textile coatings or elasticity, sound absorption and antistatic nature in carpets.

Major focus of this brochure will lie on decorative coatings, as it is the most prominent end-market. We will provide relevant application data for vinyl acetate, pure acrylic and styrene acrylic binders and demonstrate the performance of our emulsifiers in the emulsion polymerization process and their benefits in emulsion paint formulations.

World emulsion polymer demand World paint & coatings market for emulsion polymers (11,910 kilo tons) (4,730 kilo tons)

Paper/paperboard coatings

Water-based paints

Other markets

29%

40%

Adhesives & Sealants

24%

7%

Fig.2: 2013 world paints & coatings market for emulsion polymersFig.1 World emulsion polymer demand in 2013

Source:MarketsandMarkets,PolymerEmulsionMarket,October2013

70%

60%

50%

40%

30%

20%

10%

0%

Acrylics

62%

Vinyl AcetatePolymers

29%

Other

9%

2

7

TECHNICAL PRINCIPLES OF EMULSION POLYMERIZATIONEmulsion Polymerization is characterized by its heterogeneity from beginning to end, where the polymer growth takes place within micelles of surfactant stabilized monomer in water. Above a certain concentration called the c.m.c. (critical micelle concentration) surfactants form aggregates from free surfactant in aqueous solution, such as micelles (e.g. globule micelles). Therein the hydrophobic tails form the cores of the aggregates along with the non-polar substances such as monomers, oligomers or polymers while the hydrophilic surfactant heads remain in contact with the surrounding water. Although it can be observed that initiation and first chain growth take place in the aqueous phase, the formation of new micelles - whereby the growing chain becomes insoluble - is a key assumption during emulsion polymerization as polymerization in micelles controls the final particle size. Harkins’ original qualitative description of emulsion polymerization is divided into seed formation, feed stage and post reaction. The propagation reaction with monomer takes place primarily in the micelles, the monomer droplets do not compete with micelles in capturing free radicals in general due to their relatively small surface area.

Co

nver

sio

n o

f m

ono

mer

s

Monomer Droplet

M

The location of the polymerization reaction are the monomer swollen micelles

M

Micelle

P

P

P

P

SEED FORMATION FEED STAGE POST REACTION

Micelle

Monomer Droplet

Seed formation (cSUrF. > c.m.c)With a surfactant concentration (cSurf.) above the c.m.c. monomer is stabilized in monomer droplets and micelles are formed. A water-soluble initiator is introduced into the water phase, where it reacts with free monomer and forms new particles (oli-gomers) which are stabilized in micelles. Usually this phase holds up to 10% conversion.

Feed stage (cSUrF. > c.m.c)Above 10% conversion, exhaustion of micelle forma-tion occurs as the concentration of free surfactant decreases so that no more new micelles are formed and the existing particle number remains constant. The polymerization reaction continuous in the existing micelles and particles grow by monomer diffusion from droplets to the micelles.

Post reactionAt the final stage, monomer droplets disappear and monomers are converted inside the monomer swollen polymer particles.

The number of formed particles depend on different conditions such as:n concentration of emulsifier and initiatorn agitation, power inputn reactor and stirrer geometryn raw materials, impurities, swelling agents

The correlation of concentration of emulsifier and initiator on the number of particles (N) formed has been elaborated by W. V. Smith and R. H. Ewart.

Smith-Ewart-Equation N ~ [Initiator]0.4 x [Surfactant]0.6

2


EMULSION POLYMERIZATION PROCESSThree different processes are commonly used in emulsion polymerization: the batch, the semi-batch or the continuous process.

In the batch process all components are added at the beginning and the reaction starts as soon as the initiator is added (and the temperature is increased). As this process enable only limited control of particle size, coagulum formation, copolymer composition etc. the semi-batch process is often used.

In the semi-batch process only part of the total reaction formulation is added at the begin-ning to the vessel the remaining ingredients are fed during the reaction process. In order to obtain high production rates the ingredients can be added and the formed latex removed simultaneously in a continuous process. However this process becomes only interesting when a single latex is required in a very large tonnage.

As the semi-batch process is the most widely used of all processes, this is the development of emulsifiers that Clariant focused on. The advantage of this process is the control over particle size, coagulum formation, copolymer composition etc. by various modes of addi-tion of the ingredients.

The use of a single reactor allows the synthesis of a whole range of different latexes.

n In general the reactor is charged with a seed to control particle size and particle size distribution.

n After a short seed stage (in order to narrow particle size distribution) the feeding stage follows. During this phase the main polymerization takes place by continuous addition of initiator and/or monomer (emulsion) from reservoirs to the reactor with pumps. Final particle size and particle size distribution are strongly influenced by the method of introducing the ingredients.

n In a final step the reaction is stopped by adding post additives like redox systems to quench remaining free radicals and to reduce the residual monomer content.

InitiatorMonomeremulsion

reactor

Post-additives

2

9

STABILIZATION OF POLYMER DISPERSIONSParticles are stabilized by charged groups and amphiphilic molecules producing repulsive spaces between latex particles. The stabilizers should form a layer around the latex parti-cles arranging a distance sufficient to reduce van der Waals attraction of two latex parti-cles. Therefore the molecules have preferably an anchor group with an affinity for the sub-strate surface to stay attached to the surface either by physical interaction or by chemical bonding and a group with an affinity for the aqueous dispersion medium.

KEY FUNCTIONS OF THE EMULSIFIERS Emulsifiers like surfactants take up an important role in the polymerization process. Employed surfactants can interact between different surfaces as a solid/liquid due to their amphiphilic structure of polar heads and unpolar tails. As described before surfactants can form micelles, where the hydrophobic tails form the core of the aggregate in whose interior unpolar substances as polymers can be “dissolved” and the hydrophilic heads stay in con-tact with the surrounding water. Surfactants diffuse in water and adsorb with their unpolar tail at solid latex particles to stabilize solid particles. They aid in the emulsification of monomers by forming micro-reactors in which the polymerization reaction takes place by influencing conversion, particle size and distribution. Stability of the polymer particles and the final latex are maintained as well.

Furthermore it is important to influence and control the polymer and the dispersion properties by:

In all cases the relationship between particle size and size of the stabilizing molecules should be taken into account. The stabilizing macromolecules should be much smaller than the latex particles to obtain good stabilization. If the stabilizing molecules are too big, numerous points of attachment can occur and lead to flocculation, network formation and gelling.

n Electrostatic stabilization by anionic emulsifiers

n Steric stabilization by nonionic emulsifiers

n Electrosteric stabilization by anionic emulsifiers

Therefore 3 principles of particle stabilization are reported:

Typically two classes of emulsifier are used during emulsion polymerization, anionic and nonionic emulsifier. In order to achieve suitable properties it is recommended to use a combination of anionic and nonionic emulsifier.

n Regulating the glass transition temperaturen Control of the film forming temperature

n Increasing the solid content to the maximumn Achieving the required viscosityn Reducing residual monomer content

Polymer properties (influenced by the monomer)

Dispersion properties (influenced by the monomer and surfactant)

}

}

Electrostatic stabilization

Steric stabilization

PolymerParticle

Alkyl sulfates

Alkyl ethoxylates

EO/PO-Block polymers

Alkyl ethersulfates

Electrosteric stabilization

Na+Na+

S

2


ANIONIC EMULSIFIERAnionic emulsifiers are of high importance. Their main function is to produce a stable monomer emulsion and to prevent the formation of coagulum during the manufacturing process, in order to reduce grit levels and avoid production shutdowns. Additionally the anionic emulsifiers have an impact on the particle size and particle size distribution. Depending on the effect in the end application, either small particles (< 100 nanometers) or big particles (>1000 nanometers) are required

Common types of anionic surfactants used in emulsion polymerization are sulphate esters, either as alkyl sulfates or in the form of alkyl ether sulfates. Further-more, alkyl and olefin sulfonates are widely used. In certain applications phosphate esters and sulfosucci-nates are the preferred product of choice.

Key functions of the anionic emulsifier

Main emulsifier to produce stablemonomer emulsions

Controlling particle size and distribution of polymer emulsion

Prevent coagulation of polymerparticles and reduce grit levels

Formation of coagulum on the stirrer during polymerization should be pre-vented by the right choice of anionic and nonionic emulsifiers together with the right set up of the polymeri-zation process

NONIONIC EMULSIFIERThe nonionic emulsifiers strongly contribute to the quality of the final latex by providing to the polymer dispersion benefits in handling and formulation. Key requirement of a formulator for instance is an enhanced electrolyte and shear stability for application in paints. Often formulations are destabilized by electrolytes presence in water or by intro-ducing supplementary electrolytes e.g. from calcite (calcium carbonate) as filler for paints. Nonionic emulsifiers are not enhanced by electrolytes as they have no ionic group that can interact with electrolytes to get insoluble precipitate which prevent electro static/-steric stabilization. Therefore the polymer can be stabilized even in the presence of electrolytes. But the presence of nonionic emulsifiers also influence the shelf life and is beneficial for the freeze-thaw stability which helps to simplify storage and transportation.

Prominent types of nonionic emulsifiers are fatty alco-hol ethoxylates and block copolymers of ethylene and propylene oxide.

Key functions of the nonionic emulsifier

Improve latex stability

Enhance electrolyte stability

Maintain low viscosity of polymeremulsion at different shear rates

Increase freeze - thaw stability

Polymer dispersion of a laboratory batch

2

11

Set up of the performance screening test for emulsifiers

OUR APPROACH In order to support our customer’s requirements and to find the appropriate emulsifier, Clariant tested selected anionic and nonionic emulsifiers with improved environmental profile (APEO free, low VOC and hazard label free) against market standards such as ethoxylated alkyl ether sulfates and nonylphenol ethoxylates. The objective was to evaluate the impact of those emulsifiers as well as the utilized concentration level on the quality of the three major binding systems for architectural paints. Starting from styrene acrylates the test set-up was extended to vinyl acetate and pure acrylic latexes. The performance of the obtained binders was evaluated in architectural paints as well.

GUIDE RECIPES AND TEST PARAMETERS FOR THE POLYMER EMULSIONS The emulsion polymers were manufactured by a semi-continuous emulsion polymeriza-tion according to the following general procedure:The reactor is charged with water, an aliquot of the monomer mixture and emulsifiers and heated up to 80°C. The radical initiator system is added so that the temperature does not exceed 80°C (over a time period of about 15 minutes). Afterwards the remaining monomer mixture and emulsifiers are added subsequently over a period of 3 hours maintaining the reaction temperature at 80°C. After 1 hour of post-curing the reaction is cooled to room temperature and adjusted to pH 7-8 with ammonia.

Test results are shown on the following pages. Please find the detailed guide recipies for vinyl acetate, pure acrylate and stryrene acrylate on page 16 and 30.

EVALUATION OF PHYSICAL PROPERTIES AND STABILITYFor evaluation the obtained polymers were filtered off and analyzed according to the following criteria:

EVALUATION CRITERIA SHORT DESCRIPTION

Coagulum formation (> 40 µm) Weight difference after filtration over 40 µm and 100 µm strainer.

Particle size Determination of particle size by laser diffraction or dynamic lightscattering depending on the particle size.

Freeze-thaw stability (according to ISO 1147)

Stability after 5 freeze-thaw cycles (freeze at -18°C and warm up to room temperature).

Electrolyte stability A solution of polymer in 5% CaCl2 solution shows a stable dispersion directly and after 1 day at room temperature.

Viscosity profile Haake-viscosity at 1/10 sec-1 at room temperature.

Appearance after one week at 60°C The polymer is kept for 1 week at 60°C in an oven simulating shelf life for 6 months. Afterwards the polymer is evaluated visually.

3


EVALUATION OF EMULSION IN A PAINT FORMULATIONFurthermore selected polymer emulsions have been formulated into white interior wall paint and then tinted by a colorant in order to evaluate the emulsifier impact on the paint viscosity and the final tinting strength. Guide recipe of the pigment paste and procedure for tinting are shown on the following pages.

Recipe for white base paint:

Components 1 - 4 are added to a dissolver vessel and mixed. The pigment 5 and the filler 6 are added and dispersed at 3000 rpm for 5 minutes in the mill base. Then components 7 – 10 are added and the paint is homogenized for 5 minutes at 500 rpm.

NO. PRODUCT SUPPLIER DESCRIPTION CONTENT

1 Water Solvent 182 g

2 Tylose MH 10000 YP2 SE Tylose Rheology modifier 3 g

3 Mowiplus XW 330 Celanese Dispersing agent 4 g

4 D-Foam-R C 113 Clariant Foam control agent 3 g

5 Titandioxide Kronos 2160 Kronos Pigment 200 g

6 Omyacarb 5 GU Omya Filler 200 g

7 Ammonia conc.(25%) Buffering agent 2 g

8 Emulsion binder Film forming agent 400 g

9 Tafigel PUR 40 1:9 in water Münzing 4 g

10 Nipacide® BIT 10 Clariant Biocide 2 g

Sum 1000 g

3

13

Test results on the performance of nonionic emulsifier

IMPACT OF NONIONIC EMULSIFIER ON COAGULUM FORMATION AND PARTICLE SIZE

Formation of coagulum during and after polymerization is one of the main disturbances. Particle diameters from 40 – 100 µm upwards are usually not tolerated in paint applications. Bigger particles can deposit at stirrer and reactor walls, causing reactor down-time for cleaning and loss of polymer after sieving. Therefore Clariant payed particular attention at coagulum formation during development of their emulsifiers.

For screening of nonionic emulsifier Clariant focused on its Emulsogen® LCN range, ethoxylated alkyl polyethylene glycol ethers being readily biodegradable and containing no additional biocides. The Emulsogen® LCN range as APEO-free alternatives was com-pared to the nonyl phenol ethoxylates (NPEOs) of the Arkopal® range. As anionic emulsifier Emulsogen® EPA 1954 respectively Emulsogen® EPA 073 were chosen and applied in constant amounts.

For both product groups the hydrophobic part remains unchanged (nonyl phenol for Arkopal® & oxo alcohol for Emulsogen® LCN) and the hydrophilic part is variable, meaning the amount of ethylene oxide increases.

General structure of the nonionic emulsifier

NPEOs Oxo alcohol ethoxylates

Arkopal® N 100 Emulsogen® LCN 118





n = degree of ethoxylationr = nonyl phenol or oxo alcohol

4


In the graphs shown above the total coagulum formation is shown in relation to the degree of ethoxylation. Increasing ethoxylation degree shows less coagulation formation in all three tested binder systems. Especially a degree of ethoxylation > 20 EO gives a low coagulum formation. Comparing the APEO-free and -containing product ranges, the Emulsogen® LCN range is a valuable replacement.

Coagulum [ppm]

3,000

2,500

2,000

1,500

1,000

500

0

0 5 10 15 20 25 30 34 40 45

Arkopal®

N 10

0

Emul

sogen

® LCN 11

8

Arkopal®

N 2

08

Arkopal®

N 2

38

Arkopal®

N 3

07

Arkopal®

N 4

07

Emul

sogen

® LCN 2

17

Emul

sogen

® LCN 2

87

Emul

sogen

® LCN 4

07

Total coagulum formation in vinyl acetate (> 40 µm)

Degree of ethoxylation

Emulsogen® LCN range

Arkopal® N range

Coagulum [ppm]

Arkopal®

N 3

07

3,000

2,500

2,000

1,500

1,000

500

0

0 5 10 15 20 25 30 34 40 45

Arkopal®

N 10

0

Emul

sogen

® LCN 11

8

Arkopal®

N 2

08

Arkopal®

N 2

38

Arkopal®

N 4

07

Emul

sogen

® LCN 2

17

Emul

sogen

® LCN 2

87

Emul

sogen

® LCN 4

07

Total coagulum formation in pure acrylate (> 40 µm)



Arkopal® N range

Coagulum [ppm]

Arkopal®

N 3

07

3,000

2,500

2,000

1,500

1,000

500

0

0 5 10 15 20 25 30 34 40 45

Arkopal®

N 10

0

Emul

sogen

® LCN 11

8

Arkopal®

N 2

08

Arkopal®

N 2

38

Arkopal®

N 4

07

Emul

sogen

® LCN 2

17

Emul

sogen

® LCN 2

87

Emul

sogen

® LCN 4

07

Total coagulum formation in styrene acrylate (> 40 µm)



Arkopal® N range

4

15

4

IMPACT OF NONIONIC EMULSIFIER ON STABILITYClariant is aware that formation of coagulum is not the only performance criteria; also sta-bility in further applications has to be given. Clariant puts its polymer emulsion underneath a set of application tests as freeze-thaw stability and electrolyte stability (for details please see previous section: “Evaluation of physical properties”).

Stability tests of polymer dispersions - case study vinyl acetate polymers

Even in the absence of a nonionic emulsifier the formed vinyl acetate polymer shows elec-trolyte stability, as well as stable appearance after 1 week at 60°C simulating shelf life for 6 months. However Clariant strongly recommend the use of a nonionic emulsifier to improve freeze-thaw-stability which is given by the nonionic emulsifier. Especially Emulsogen® LCN 287 and 407 show excellent stability. For pure acrylic and styrene acrylate polymers Emulsogen® LCN 287 and 407 not only improve freeze-thaw-stability but also give elec-trolyte stability to the polymer which is not given in the absence of a nonionic emulsifier.

PRODUCT FREEZE-THAW-STABILITY

ELECTROLYTE STABILITY 25°C TO 60°C

ELECTROLYTE STABILITY AFTER 1 DAY

APPEARANCE AFTER 1WEEK AT 60°C

Without nonionic ✗ 3 3 3

Emulsogen® LCN 118 ✗ 3 3 3

Emulsogen® LCN 217 ✗ 3 3 3

Emulsogen® LCN 287 3 3 3 3

Emulsogen® LCN 407 3 3 3 3

Arkopal® N 100 ✗ 3 3 3

Arkopal® N 208 3 3 3 3

Arkopal® N 238 3 3 3 3

Arkopal® N 307 3 3 3 3

Arkopal® N 407 3 3 3 3





FREEZE-THAW-STABILITY


ELECTROLY-TE STABILITY AFTER 1 DAY


Without nonionic ✗ ✗ ✗ 3 ✗ ✗ ✗ ✗

Emulsogen® LCN 287 3 3 3 3 3 3 3 3

Emulsogen® LCN 407 3 3 3 3 3 3 3 3

PURE ACRYLIC POLYMER STYRENE ACRYLATE POLYMER

Stability tests of polymer dispersions - case study pure acrylic and styrene acrylate polymers.

3= pass ✗ = fail

3= pass ✗ = fail


4

Guide procedure for pure acrylate

Initiator solution 76.8 ml (0.3% PPS/ monomers)Potassium persulfate 3.0%Demineralized water 97.0%

Monomer emulsion 1100.0 gDemineralized water 282 gEmulsogen® EPA 073 22.5 g (0.8% active/

monomers)Nonionic emulsifier (70%) 21.7 g (2.0% active/

monomers)Sodium bicarbonate 6 gn-Butyl acrylate 380 gMethyl methacrylate 380 gMethacrylic acid 7.6 g

Reactor charge 370 g1) Demineralized water 476.8 g2) Emulsogen® EPA 073 11.3 g (0.4% active/

monomers)3) Initiator solution 19.2 g (25% of total)4) Monomer emulsion 27.5 g (2.5% of total)

Total of 1500 g polymer dispersionSolid content about 53%

The reactor is charged with demineralized water (1) and Emulsogen® EPA 073 (2) and heated up to 80°C. Subsequently the initiator solution (3) and the monomer emulsion (4) are added. After 15 minutes, the remaining monomer solution is fed to the reactor over the subsequent 3 hours at 80°C.

Post reactionThe reaction continues to stir for 1 hour at 80°C. Then it is cooled down to room temperature and the pH is adjusted to 7 – 8 with ammonia.

Guide procedure for styrene acrylate

Initiator solution 63.7 ml (0.4% APS/ monomers)Ammonium persulfate 5.0%Demineralized water 95.0%

Monomer emulsion 1000.0 gDemineralized water 165 gEmulsogen® EPA 073 26.3 g (0.9% active/

monomers)Caustic soda (40%) 6.3 g2-Ethyl hexyl acrylate 340 gStyrene 450 gAcrylic acid 11.9 g

Reactor charge 474 g1) Demineralized water 678.1 g2) Emulsogen® EPA 073 126.3 g (0.9% active/

monomers)3) Acrylic acid 11.9 g4) Caustic soda (40%) 16.5 g5) Initiator solution 15.9 g (25% of total)6) Monomer emulsion 25.0 g (2.5% of total)

Total of 1600 g polymer dispersion, solid content about 53%

The reactor is charged with components (1) to (4) and heated up to 80°C. Subsequently the initiator solution (5) and the monomer emulsion (6) are added. After 15 minutes, the remaining monomer and initiator solution are fed to the reactor over the subsequent 3 hours at 80°C.

Post reaction1) Initiator solution 15.9 g (25% of total)2) Nonionic emulsifier 79.0 g (2.0 % active/

monomers)3) NaOH 40%ig 6.5 g4) tert.-Butylhydroperoxid 2.2 g 70% 5) Sodium disulfite 10% 15.8 g

Initiator solution (1) is added and the reaction is stirred for additional 40 minutes at 80°C. The components (2) and (3) are added over 20 minutes and the reaction is cooled down to 35°C. The reaction is stopped by adding components (4) and (5), stirred for an additi-onal 60 minutes, the pH is then adjusted to 7 – 8 with ammonia.

Guide procedure for vinyl acetate

Initiator solution 170.0 ml (0.25% PPS/ monomers)Potassium persulfate (PPS) 1.2%Demineralized water 98.8%

Monomer emulsion 795.0 gVinyl acetate 75%VeoVa 10, Momentive 25%

Reactor charge 689.5 g1) Demineralized water 476.8 g2) Tylose H200YG2 15.8 g3) Sodium carbonate 5.9 g4) Emulsogen® EPA 1954 14.2 g (0.5% active/

monomers)5) Nonionic emulsifier 22.7 g (2.0% active/

monomers)6) Acetic acid 99% 1.7 g7) Initiator solution 67.9 g (40% of total)8) Monomer mixture 79.5 g (10% of total)

The reactor is charged with components (1) to (6). Under stirring the initiator solution and the monomer mixture are added and the reaction mixture is heated to 76°C. After 15 minutes, the remaining monomer solution is fed to the reactor over the subsequent 2.5 hours at 80°C and the initiator over the sub-sequent 2.75 hours.

Post reactionThe reaction is continued to stir for 2 hours at 80°C. Then it is cooled down to room temperature and 3.2 g Nipacide® CI 15 (0.15%) are added as preservative.

OVERVIEW GUIDE PROCEDURES - NONIONIC EMULSIFIERThe performance tests on the nonionic emulsifier are based on the following guide procedures. As anionic emulsifier Emulsogen® EPA 073 (for pure acrylate, styrene acrylate) or Emulsogen® EPA 1954 (for vinyl acetate) have been used. Only the nonionic emulsifier has been exchanged in order to obtain representative test results for comparison.

17

Ammonium alkyl ether sulfate

EO/PO alkylene glycol ether sulfate, ammonium salt

SODIUM ALKYL ETHER SULFATE

AMMONIUM ALKYL ETHER SULFATE

EO/PO ALKYLENE GLYCOL ETHER SULFATE, AMMONIUM SALT

SODIUM NPEO ETHER SULFATE

Emulsogen® EPA 073 Emulsogen® LA 083 Emulsogen® PF 20 S Hostapal® BVQ 9

Sodium alkyl ether sulfate 20 EO (benchmark)

Emulsogen® LCA 213 Emulsogen® APS 100 Hostapal® BVQ 25

Test results on the performance of anionic emulsifier

For deeper understanding of polymer properties Clariant also investigated in screening anionic emulsifier from different classes. As benchmark a commonly accepted emulsifier has been chosen.

IMPACT OF ANIONIC EMULSIFIER IN STYRENE ACRYLIC BINDERAs anionic emulsifier surfactants from 4 different classes were chosen and were added with 0.5%, 1.0% or 1.5% of the active matter respectively. As nonionic emulsifier Emulsogen® LCN 287 was chosen and applied in constant amounts.

General structure of the anionic emulsifier

Sodium alkyl ether sulfate

5

Sodium NPEO ether sulfate


In the graph above the total coagulum formation for three concentrations of all screened emulsifiers is shown. In combination with Emulsogen® LCN 287 all selected emulsifiers showed moderate formation of coagulum. Comparison of Clariant’s sodium alkyl ether sulfate, Emulsogen® EPA 073 with a 20 EO containing product showed less coagulation. A dosage of 1.0% - 1.5% active content tends to result in a reduced formation of coagulum. Especially Emulsogen® PF 20 S is a recommendable emulsifier. This is supported by good freeze-thaw- and electrolyte-stability of the tested ammonium salt.

Stability of styrene acrylic polymers from 1.0% anionic emulsifier


ELECTROLYTE STABILITY INSTANT


APPEARANCE AFTER 1W/60°C

Emulsogen® EPA 073

Emulsogen® LA 083

Emulsogen® LCA 213

Emulsogen® PF 20 S

Emulsogen® APS 100

Hostapal® BVQ 9

Hostapal® BVQ 25

✗

3

3

3

3

✗

3

Total coagulum formation (> 40 µm) in styrene acrylic binder

Coagulum [ppm]

Anionic emulsifier concentration

800

700

600

500

400

300

200

100

0Emulsogen®

EPA 073Sodium alkylether sulfate

(20 EO)

Emulsogen® LA 083

Emulsogen® LCA 213

Emulsogen® PF 20 S

Emulsogen® APS 100

Hostapal® BVQ 9

Hostapal® BVQ 25

0.5% 1.5% active matter1.0%

3= pass ✗ = fail

5

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

19

Coagulum formation as function of the emulsifier (Emulsogen® EPA 073)

The graph above shows the total coagulum formation (bubble size) as function of the concentration of Emulsogen® EPA 073 in the reactor charge (X-axis) and the monomer emulsion (Y-axis). Significant for coagulum formation is the dosage of the anionic emulsifier in the reactor charge. Also a dosage above the c.m.c. is necessary for initial micelle forma-tion. An over dosage should be prevented to avoid excessive coagulation. If the surfactant concentration in the seed stage is too high new particles can be formed during the feeding of additional monomer causing a broad particle size distribution. A dosage of 0.1% of anionic emulsifier showed reasonable results and prevent excessive coagulation forming.

As described in the first section of this brochure not only the emulsifier itself prevent coagulum formation but also the dosage of the ingredients. Therefore Clariant deepened its investigation on the influences of the concentration of the employed emulsifiers using the example of Emulsogen® EPA 073.

Anionic emulsifier in the monomer emulsion

1.8%

1.6%

1.4%

1.2%

1.0%

0.8%

0.6%

0.4%

0.2%

0.0%

0.0% 0.1% 0.2% 0.3% 0.4% 0.5%

Anionic emulsifier in the reactor charge

Bubble size = coagulum formation in ppm

292

397

1052

1439

183

1441

1867

5


IMPACT OF THE STYRENE ACRYLIC BINDER IN PAINTS AND COLORANTS Paints are one of the biggest market segments for the application of polymer dispersions as pigment binder. Beside the binders paints consist of water as solvent, pigments and fillers contributing the color and additives like dispersing agents to obtain a homogenous and easy applicable dispersion. Binders are the backbone of paints responsible for the film forming and the main component of a pain (beside water).

An essential application of paints is there decorative property coming from the pigments. As the pigments are the most expensive ingredient in a paint all additives support to get the highest tinting strength in order to minimize the pigment amount and reduce cost. Therefore the obtained binder have been formulated into a paint and been evaluated by their capability to enhance tinting strength of tinted paints.



2 Hostaperm® Blue B2G Clariant Pigment 50 g

3 Dispersogen® PTS Clariant Dispersing agent 6 g

4 Polyglykol 200 LVC Clariant Humectant 10 g



Sum 100 g

Pigment paste phthalo blue (PB 15:3)

5



2 Hostaperm Violet RL 02 Clariant Pigment 30 g





Sum 100 g

Pigment paste dioxazine violet (PV 23)

Add all components to a grinding vessel and prepare a paste that all pigments are wetted with the dissolver disk. Then ground in a bead.

For tinting of the white base paint add 2% of the pigment paste to 98% of the emulsion paint and mix in a paint shaker for 1 minute.

21

Color strength (base paint tinted with 2% PB 15:3 colorant)


110%

105%

100%

95%

90%

85%

80%Emulsogen®

EPA 073Sodium alkyl ether sulfate

(20 EO)

Emulsogen® PF 20 S

Hostapal® BVQ 9

Hostapal® BVQ 25

Genapol® LA 083

Emulsogen® LCA 213

Emulsogen® APS 100


Particle size and color strength (base paint tinted with 2% PB 15:3 colorant)

Color strength in %

Emulsion polymer size [nm]

Bubble size = total concentration of active matter of the anionic emulsifier

• Emulsogen® EPA 073

• Emulsogen® PF 20 S

• Hostapal® BVQ 9

• Emulsogen® APS 100

5

120%

110%

100%

90%

80%

70%

60%

50%

100 120 140 160 180 200 220 240 260

1.6%1.1%

0.6%

1.6%1.1%

0.6%0.6%

280

1.6%0.6%

1.1%1.6%1.6%

1.1%


Color strength (base paint tinted with 2% PV 23 colorant)


180%

170%

160%

150%

140%

130%

120%

110%

100%

90%

80%Emulsogen®

EPA 073Sodium alkyl ether sulfate

(20 EO)

Emulsogen® PF 20 S

Hostapal® BVQ 9

Hostapal® BVQ 25

Genapol® LA 083

Emulsogen® LCA 213

Emulsogen® APS 100


Sodium and ammonium salts of alkyl ether sulfates don’t show significant differences. Sulfate esters of EO/PO block copolymers as Emulsogen® PF 20 S and Emulsogen® APS 100 tend to form larger particles with increased tinting strength in paint formulations. Tinting of paints with styrene acrylic binder with phthalo blue (PB 15:3) and dioxazine violet (PV 23) showed highest tinting strength for Emulsogen® PF 20 S. Thereby the choice of the appropriate emulsifier is influencing the color strength much more then the concentration of the emulsifier used during the polymerization process.

Particle size and color strength (base paint tinted with 2% PV 23 colorant)

Bubble size = total concentration of active matter of the anionic emulsifier

Color strength in %

210%

190%

170%

150%

130%

110%

90%

70%

50%100 120 140 160 180 200 220 240 280

Emulsion polymer size [nm]

1.1%

1.6%

1.6%

1.1%

1.6%1.1%0.6%

1.6%

1.1%

0.6%0.6%

0.6%

• Emulsogen® EPA 073

• Emulsogen® PF 20 S

• Hostapal® BVQ 9

• Emulsogen® APS 100

5

260

23

IMPACT OF ANIONIC EMULSIFIER IN VINYL ACETATE BINDER


SODIUM ALKYL SULFONATES

SODIUM OLEFINE SULFONATE

SODIUM NPEOETHER SULFATE

Emulsogen® EPA 1954 Hostapur® OS liq. Emulsogen® PF 20 S Hostapal® BVQ 9

Genapol® LRO liq.

Emulsogen® EPA 073

Sodium alkyl ether sulfate (20 EO)

As anionic emulsifier for vinyl acetate binder surfactants from 4 different classes were chosen and Emulsogen® LCN 287 as anionic emulsifier was added in constant amounts.


Sodium olefine sulfonate Sodium NPEO ether sulfate

General structure of anionic emulsifier

5

EO/PO alkylene glycol ether sulfate, ammonium salt

Coagulum formation and viscosity of vinyl acetate binder

coagulum [ppm] Viscosity [mPas]

180

160

140

120

100

80

60

40

20

0Emulsogen®

EPA 1954Genapol®LrO liq.

Emulsogen® EPA 073

Hostapur®OS liq.

Sodium alkylether sulfate

(20EO)

Emulsogen®PF 20 S

Anionic emulsifier

30

115

161 15203

87

3225

56

70

70

80

52

97

46

79

5

58

9000

Coagulum 40 µm - 100 µm

Coagulum > 100 µm

Viscosity (10/s)

37

57

9000

8000

7000

6000

5000

4000

3000

2000

1000

0Hostapur®

BVQ 9

56


Stability of vinyl acetate polymers from 1.4% active amount of anionic emulsifier

PRODUCT FREEZE- THAW – STABILITY




Emulsogen® EPA 1954

Genapol® LRO liq.

Emulsogen® EPA 073

Sodium alkyl ether sulfate 20 EO (marked emulsifier)

Hostapur® OS liq.

Emulsogen® PF 20 S

Hostapur® BVQ 9

✗

✗

✗

✗

✗

✗

3

3

3

3

3

3

3

3

All tested emulsifier showed moderate coagulum formation in combination with Emulsogen® LCN 287 as nonionic component in the test set-up. However Emulsogen® EPA 073 and sodium alkyl ether sulfate (20 EO) are not the emulsifiers of choice as their polymer dispersions show a high viscosity. Genapol® LRO liq. shows lowest viscosity and low coagulum formation. Electrolyte and shelf life stability is given with all tested emulsifier. If freeze-thaw stability should be ensured as well Emulsogen® EPA 1594 is a favorable anionic emulsifier for emulsion polymerization of vinyl acetate binder.

IMPACT OF THE VINYL ACETATE BINDER IN PAINTS AND COLORANTS

Addallcomponentstoagrindingvesselandprepareapastethatallpigmentsarewettedwiththedissolverdisk.Thengroundinabeadmillfor45minutesat3000roundsperminutewithadouble-millingdisc.

Fortintingofthewhitebasepaintadd2%ofthepigmentpasteto98%oftheemulsionpaintandmixinapaintshakerfor1minute.








Sum 100 g


Paints containing vinyl acetate binders were evaluated by tinting with phthalo blue (PB 15:3) pigment paste.

✗ = fail

3= pass

5

3

3

3

3

3

3

3

3

3

3

3

3

3

3

25

Correlation of tinting strength (PB 15:3) and latex particle size

115%

110%

105%

100%

95%

90%

85%

150 165 180 195 210 225 240 255

Particle size [nm]

Tinting strength

Genapol®LROliq.

Sodiumalkylethersulfate(20EO)

Emulsogen®EPA073

Emulsogen®EPA1954

Emulsogen®PF20S

Hostapur®OSliq.

Hostapal®BVQ9154/88%

163/107%

168/100%

253/106%

176/96%

184/110%

Polymer dispersions of Emulsogen® EPA 073 and sodium alkyl ether sulfate (20 EO) give high tinting strength despite their high viscosity which limits the application. Polymeric binders of Emulsogen® EPA 1954 in contrast have low viscosity and high freeze-thaw stability. Although the polymer dispersion has less tinting strength, Emulsogen® EPA 1954 can be an attractive alternative as it is a cost-efficient emulsifier for emulsion polymerization. Polymer dispersions of Genapol® LRO liq. show an increased tinting strength at low viscosity compared to Emulsogen® EPA 1954 and have a comparable performance profile to the sodium NPEO ether sulfate Hostapal® BVQ 9. Duo to the small particle size of polymer dispersions of Genapol® LRO liq., this emulsifier is a suitable candidate for the polymerization of vinyl acetate.

5

167/101%


IMPACT OF ANIONIC EMULSIFIER IN PURE ACRYLIC BINDERAs anionic emulsifier Emulsogen® EPA 073 was chosen and was added with 0.3%, 0.5% or 0.7% of active matter respectively in the reactor charge. As nonionic emulsifier Emulsogen® LCN 287 was chosen and applied in constant amounts.

Coagulum 40 µm - 100 µm

Coagulum > 100 µm

Partice Size

Properties of pure acrylic binders of Emulsogen® EPA 073

Coagulum [ppm] Particle size [nm]

1500

1350

1200

1050

900

750

600

450

300

150

0

150

135

120

105

90

75

60

45 30

15

00.3% 0.5% 0.7%

66

127 245

1213

257

659

142

107103

Concentration of active matter of Emulsogen® EPA 073 in the reactor charge

In the graph shown above the particle size, the total coagulum formation and the viscosity of the polymer dispersion as function of the concentration in the monomer emulsion of Emulsogen® EPA 073 is shown. Although the particle size at 0.3% of Emulsogen® EPA073 is slightly higher during reaction less coagulum is formed. Therefore further screening of anionic emulsifier surfactants from 5 different classes was carried out with 0.3% anionic emulsifier in the reactor charge, as nonionic emulsifier Emulsogen® LCN 287 was chosen and applied in constant amounts.


AMMONIUM ALKYL ETHER SULFATE

EO/PO ALKYLENE GLYCOL ETHER SULFATE, AMMONIUM SALT

SODIUM NPEO ETHER SULFATE

SODIUM OLEFINE SULFONATE

Emulsogen® EPA 073


Genapol® LRO liq.

Emulsogen® LA 083

Emulsogen® LCA 213

Emulsogen® PF 20 S Hostapal® BVQ 9

Hostapal® BVQ 25

Hostapur® OS liq.

5

27


Ammonium alkyl ether sulfate

Sodium olefine sulfonate

EO/PO alkylene gycol ether sulfate, ammonium salt

Sodium NPEO ether sulfate

General structure of anionic emulsifier

5

The graph above shows the coagulum formation of different anionic emulsifier in a pure acrylic binder recipe in combination with Emulsogen® LCN 287. Emulsogen® EPA 073, Hostapur® OS liq. and Hostapal® BVQ 9, all showed a low coagulum formation during the preparation of the binder and low to moderate viscosity.

As shown in the following table the dispersions of all emulsifiers were stable against electrolytes and during storage. If freeze-thaw stability is required Emulsogen® EPA 073 and Hostapur® OS liq. are the best candidates for emulsion polymerization.

Coagulum formation and viscosity in pure acrylic binder

800

700

600

500

400

300

200

100

0

1500

1300

1100

900

700

500

300

100Emulsogen®

EPA 073Hostapur®

OS liq.Sodium alkylether sulfate

(20 EO)

Emulsogen® LA 083

Emulsogen® LCA 213

Emulsogen® PF 20 S

Hostapal®

BVQ 9Hostapal®

BVQ 25

Coagulum > 100 µm ViscosityCoagulum 40 µm - 100 µm

Coagulum [ppm] Viscosity [mPas]

1310

336226

66

127

1333 14931163

428

56

977

18

352

45

37

73

90

550400

302

465 467

1000

Emulsogen®

LrO liq.


Stability of acrylic polymers from 1.5% active amount of anionic emulsifier

FREEZE-THAW – STABILITY




Emulsogen® EPA 073

Hostapur® OS liq.

Genapol® LRO liq.


Emulsogen® LCA 213

Emulsogen® PF 20S

Hostapal® BVQ 9

Hostapal® BVQ 25

3

✗

✗

✗

✗

✗

✗

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

✗ = fail3= pass

5

29

IMPACT OF THE PURE ACRYLIC BINDER IN PAINTS AND COLORANTSThe obtained binders have been formulated into a paint and the tinting strength has been evaluated by tinting with phthalo blue (PB 15:3) pigment paste.

Addallcomponentstoagrindingvesselandprepareapastethatallpigmentsarewettedwiththedis-solverdisk.Thengroundinabeadmillfor45minutesat3000roundsperminutewithadouble-millingdisc.

Fortintingofthewhitebasepaintadd2%ofthepigmentpasteto98%oftheemulsionpaintandmixinapaintshakerfor1minute.








Sum 100 g


Tinting strength of PB 15:3 in pure acrylic binder

The graph above shows that the particle size of all emulsion polymers was below 170 nm. Best results in tinting strength were observed for the latexes made with Hostapal® BVQ 25 and Emulsogen® PF 20 S. Genapol LRO liq. and Hostapur OS liq. showed lowest tinting strength, all other emulsifier showed comparable results. As the use of nonylphenol ethoxylates like Hostapal® BVQ 25 is getting more and more regulated. Therefore Emulsogen® PF 20 S is the best emulsifier for high tinting strength for applications longterm regulatory compliance products. If additional parameters like coagulum formation, stability and par-ticle size should be taken in consideration Emulsogen® EPA 073 showed a well balanced profile to be a suitable emulsifier for emulsion polymerization.

115%

110%

105%

100%

95%

90%

85%

80%

75%120 130 140 150 160 170

Particle size[nm]

Tinting strength

156/112%

142/100%

121/90%

160/96%

124/102%

127/101%

Hostapur®OSliq.

Genapol®LROliq.

Sodiumalkylethersulfate(20EO)

Emulsogen®EPA073

Emulsogen®PF20S

Emulsogen®LCA213

Hostapal®BVQ9

Emulsogen®LA083

Hostapal®BVQ25

165/108%

5

121/80%

140/98%


OVERVIEW GUIDE PROCEDURES - ANIONIC EMULSIFIER

Guide procedure for pure acrylic binder

Initiator solution 46.6 ml (0.3% PPS/ monomers)Potassium persulfate 5.0%Demineralized water 95.0%

Monomer emulsion 1100.0 gDemineralized water 302.9 gAnionic emulsifier 31.8 g

(1.2% active/ monomers)Emulsogen® LCN 287 20.5 g (2.0% active/

monomers)Acrylic acid 7.2 gMethacrylic acid 14.4 gMethacryl amide 7.2 g2-Ethylhexyl acrylate 315.0 gMethyl methacrylate 401.0 g

Initial charge 430.0 g1) Demineralized water 334.8 g2) Anionic emulsifier 8.0 - 18.6 g (0.3 - 0.7% active/



The reactor is charged with demineralized water (1) and anionic emulsifier (2) and heated up to 80°C. Subsequently the initiator solution (3) and the monomer emulsion (4)is added. After 15 minutes, the remaining monomer solution is fed to the reactor over the subsequent 3 hours at 80°C.

Post reactionAmmonia sol. 10% 21 mL

The dispersion is kept for additional 30 minu-tes at 80°C and ammonia solution is added. Finally the reaction is cooled and the pH is adjusted to 7 – 8.

Guide procedure for styrene acrylic binder

Initiator solution 74.3 ml (0.3% SPS/

monomers)Sodium persulfate 3.5%Demineralized water 96.5%

Monomer emulsion 1060.0 gDemineralized water add to 1060.0 gAnionic emulsifier 11 - 22 g (0.5 – 1.5% active/

monomers)Emulsogen® LCN 287 28.9 g (3.0% active/

monomers)Acrylic acid 7.5 gMethacrylic acid 15.0 gMethacryl amide 15.0 g2-Ethylhexyl acrylate 412.0 gStyrene 338.0 g

Reactor charge 415.5 g1) Demineralized water 370.6 g2) Anionic emulsifier 5.5 - 11 g (0 - 0.3% active/



The reactor is charged with demineralized water (1) and anionic emulsifier (2) and heated up to 80°C. Subsequently the initiator solution (3) and the monomer emulsion (4) is added. After 15 minutes, the remaining monomer solution is fed to the reactor over the subse-quent 3 hours at 80°C.

Post reaction1) Initiator solution 15.9 g (25% of total)2) tert.-Butylhydroperoxid 2.2 g 70% 3) Sodium disulfite 10% 15.8 g4) Sodium disulfite 5% 30.0 g5) NaOH 10% 37.5 g

Initiator solution (1) is added and the reaction is stirred for an additional 60 minutes at 80°C. Then cool down to 60°C, add components (2) and stir for additional 30 minutes. Then add (3). After 30 minutes add (4), cool down to 35°C and add (5). Finally adjust pH to 7 – 8 with NaOH.

Guide procedure for vinyl acetate binder

Initiator solution 55.8 ml (0.22% SPS/ monomers)Sodium persulfate 3.0%Demineralized water 97.0%

Monomer emulsion 1030.0 gWater 218.0 gAnionic emulsifier 40.0 g (1.44% active/

monomers)Emulsogen® LCN 287 10.7 g (1.0% active/

monomers)Na vinyl sulfonate (20%) 9.0 gAcrylic acid 2.3 gVinyl acetate 562.5 gVeoVa 10, Momentive 187.5 g

Initial charge 446.1 g1) Demineralized water 375.7 g2) Anionic emulsifier 1.7 g (0.06% active/

monomers)3) Emulsogen® LCN 287 2.1 g (0.2% active/

monomers)4) Na vinyl sulfonate (20%) 8.3 g5) Sodium acetate x3H2O 1.5 g6) Sodium disulfite 1.5 g7) Initiator solution 3.9 g (7% of total)8) Monomer mixture 51.5 g

(5% of total)

Total of 1500 g polymer dispersion, solid content about 52%

The reactor is charged with components (1) – (6) and heated up to 70°C. Subsequently the initiator solution (7) and the monomer emulsion (8) are added. After 15 minutes, the remaining monomer solution and initiator solution are fed to the reactor over the sub-sequent 3 hours at 70°C. Afterwards the reac-tion is stirred for an additional hours at 75°C.

Post reaction1) Sodium disulfite 5% 3.7 g2) tert.-Butylhydroperoxid 2.7 g 7% 3) Sodium disulfite 5% 14.7 g4) Ammonia sol. 12.5% 2.5 g

Add component (1) at 75°C and wait for 15 minutes. Then start cooling down. Add component (2) at 50°C and stir for 15 minutes. Then add component (3) under stirring and cool down to < 35°C. Finally add component (4) (ammonia solution) to adjust the pH to 7 - 8.

The performance tests on the anionic emulsifier are based on the following guide procedures. As nonionic emulsifier Emulsogen® LCN 287 has been used. Only the anionic emulsifier has been exchanged in order to obtain representative test results for comparison.

5

31

Test results and benefits at a glance

BENEFITS AT A GLANCE

PERFORMANCE ANIONIC EMULSIFIER NONIONIC EMULSIFIER

Performance in emulsion

polymerization

• Improved stability of the monomer emulsion

• Low coagulum formation during polymerization

• Control of particle size of the polymer dispersion

• Improved viscosity of the polymer dispersion

• Similar polymerization results to APEOs

• Improved shelf life (high freeze thaw stability),

electrolyte stability and compatibility with paint

formulations

Performance in paint binders • Higher tinting strength of the tinted emulsion

paints

• High pigment compatibility with other paint

components

Additional benefits • Improved environmental profile: APEO free,

low VOC. Emulsogen® PF 20S is label free.

Emulsogen® EPA 073 and Genapol® LRO liq.

are readily biodegradable

• Easy to handle: Low viscous, liquid products,

low freeze points and fastly dissolving in water

• Improved environmental profile: APEO free,

hazard label free, biodegradable, low VOC

• Easy to handle: Low viscous, liquid products,

low freeze points and fastly dissolving in water

BEST PERFORMING EMULSIFIER COMBINATIONS

POLYMER EMULSION ANIONIC EMULSIFIER NONIONIC EMULSIFIER

Vinyl acetate 4.8% Genapol® LRO liq. 1.4% Emulsogen® LCN 287

Pure acrylic 4.0% Emulsogen® EPA 073 2.9% Emulsogen® LCN 287/407

Styrene acrylic 3.2% Emulsogen® PF 20 S 4.3% Emulsogen® LCN 287

6

Based on the screening results Clariant recommends the following emulisifer combination for application as binders in architectural paints.


Starting recipes for further polymer dispersions

Paints and coatings is the biggest market segment for the application of polymer dispersions as pigment binders and film forming polymers. Apart from this application polymer dispersions are used for adhesives, construction, textile and paper coatings. The following recipes give examples for the synthesis of polymer dispersions. Clariant emulsifiers are suitable process aids for all of these applications.

Styrene acrylate dispersion for tile adhesives

Sodium persulfate solution 65.6 g solution made of 7.5 % sodium peroxodisulfate solution and 92.5 % deionized water

Sodium metabisulfite solution 10.2 g solution made of 10% sodium metabisulfite and 90% water

Monomer emulsionDeionized water 206.4 gEmulsogen® EPA 073 23.1 gEmulsogen® LCN 287 16.7 gSodium hydrogen carbonate 1.8 gMethacryl amide 12.0 gMethacrylic acid 8.0 gAcrylic acid 12.0 g2-Ethyl hexyl acrylate 480.0Styrene 300.0 g

Sodium persulfate solution, sodium metabisulfite solution and monomer emulsion are prepared by mixing.

Reactor chargeDeionized water 422.5 gEmulsogen® EPA 073 5.8 gMonomer emulsion 26.5 gSodium persulfate solution 16.0 g

The reactor is charged with water, Emulsogen® EPA 073 and 26.5 g of the monomer emulsion and heated up to 80°C under stirring. Then 16.0 g of the sodium persulfate solution is added and the polymerization reaction begins. After 15 minutes, start feeding the remaining 38.4 g sodium persulfate solution and complete the addition of the monomer emulsion to the reactor over the subsequent 3.5 hours at 80°C.

Post reactionAdd 9.6 g of the sodium persulfate solution and stir the dispsersion for 30 minutes at 80°C. Then add 10.6 g sodium metabsulfite solution and keep 80°C for another 30 min-utes. Then cool down to 35°C and add 8.0 g ammonia solution and 3.0 g Nipacide CI 15.

Vinyl acetate acrylic dispersion for textile coatings


Sodium metabisulfite solution 4.2 g solution made of 10% sodium metabisulfite and 90% water

Monomer emulsion Deionized water 182.8 g Emulsogen® EPA 073 15.6 g Emulsogen® LCN 287 12.0 g Sodium acetate 1.6 g Vinyl sulfonate (30% solution) 8.0 g N-hydroxymethyl acrylamide 80.0 g(50% solution) 2-Ethyl hexyl acrylate 30.0 g Vinyl acetate 730.0 g

Sodium persulfate solution, sodium metabi-sulfite solution and monomer emulsion are prepared by mixing.

Reactor chargeDeionized water 464.2 gSodium acetate 0.5 gMonomer emulsion 28.6 gSodium metabisulfite solution 3.4 gSodium persulfate solution 17.0 g

The reactor is charged with water, sodium acetate and the monomer emulsion and heated up to 72°C under stirring. Sodium persulfate and sodium metabisulfite solu-tions are added as a redox initiator system. After 15 minutes, 40.7 g of the remaining sodium persulfate solution is fed and the remaining monomer emulsion fed to the reactor over the subsequent 4.5 hours at 72°C.

Post reactionHeat the resulting polymer dispersion to 82°C, add a further 10.2 g sodium persulfate solution and keep this temperature for 30 minutes. Then add 0.8 sodium metabisulfite solution and keep 82°C for 15 minutes. Cool down to 35°C and add 3.2 g Nipacide CI 15 as preservative.

Pure acrylic dispersion for pressure sensitive adhesives


Hydrogen peroxide solution 1.6 g solution made of 35% hydrogen peroxide in water

Monomer emulsionDeionized water 197.9 gEmulsogen® EPA 073 23.4 gEmulsogen® LCN 287 16.9 gSodium hydrogen carbonate 1.8 gAcrylic acid 30.0 gMethyl methacrylate 40.0 gn-Butyl acrylate 750.0 g

Sodium persulfate solution, hydrogen perox-ide and monomer emulsion are prepared by mixing.


The reactor is charged with water, Emulsogen® EPA 073 and the monomer emulsion and heated up to 80°C under stirring. Then the sodium persulfate solution is added and the polymerization reaction begins. After 15 minutes start feeding the remaining 39.4 g sodium persulfate solution and the addition of the monomer emulsion to the reactor is completed over the sub-sequent 3.5 hours at 80°C.

Post reactionAdd 1.6 g hydrogen peroxide solution and keep 80°C for 1 hour. Then cool down to 35°C and add 8.0 g ammonia solution and 3.0 g Nipacide CI 15.

7

33

Hard styrene acrylate dispersion for paper coatings


Sodium metabisulfite solution8.5 g solution made of 10% sodium metabisulfite and 90% water

Monomer emulsionDeionized water 188.6 gEmulsogen® EPA 073 43.3 gEmulsogen® LCN 287 22.3 gSodium hydrogen carbonate 1.8 gMethacrylic acid 24.0 gn-Butyl acrylate 400.0 gStyrene 380.0 g

Sodium persulfate solution, sodium metabisulfite solution and monomer emulsion are prepared by mixing.


The reactor is charged with water, Emulsogen® EPA 073 and the monomer emulsion and heated up to 80°C under stirring. Then 16.1 g of the sodium persulfate solution is added and the polymerization reaction begins. After 15 minutes start feeding the remaining 38.6 g sodium persulfate solution and complete the addition of the monomer emulsion to the reactor over the subsequent 3.5 hours at 80°C.

Post reactionAdd 9.6 g of the sodium persulfate solution and stir the dispsersion for 30 minutes at 80°C. Then add 8.5 g sodium metabsulfite solution and keep 80°C for another 30 min-utes. Then cool down to 35° and add 8.0 g ammonia solution and 3.0 g Nipacide CI 15.

7

Type Vinyl acetate acrylic dispersion for textile coatings

Pure acrylic dispersion for pressure sensitive adhesives

Styrene acrylate dispersion for tile adhesives

Hard styrene acrylate dispersion for paper coatings

Solid content 46.5% 57.0% 54.3% 53.5%

pH (10% in water) 3.6 3.5 4.6 7.2

Coagulate > 40 µm 425 ppm 740 ppm 492 ppm 255 ppm

Particle size 279 nm 166 nm 106 nm 118 nm

Viscosity at 1/sec n.a. 8860 mPas 22500 mPas 4370 mPas

Viscosity at 100/sec 37 mPas 430 mPas 710 mPas 190 mPas

Freeze thaw stability

Electrolyte stability

Storage stability

3

3

3

3

3

3

3

3

3

3

3

3

Emulsion properties of further applications

3= pass


The following leaflet gives an overview on Clariant’s range of anionic and nonionic emulsifiers for Emulsion Polymerization.

Additional to the products’ application area, please find relevant information on the products’ properties (e.g. APEO-free, low VOC) as well as on their labeling clas-sification, registration in chemical inven-tories and compliance with food contact regulations.

RANGE OF ANIONIC AND NONIONIC EMULSIFIERS

Emulsion Polymerization

This information corresponds to the present state of our knowledge and is intended as a general descrip-tion of our products and their possible applications. Clariant makes no warranties, express or implied, as to the information’s accuracy, adequacy, sufficiency or freedom from defect and assumes no liability in connection with any use of this information. Any user of this product is responsible for determining the suitability of Clariant’s products for its particular application. * Nothing included in this information waives any of Clariant’s General Terms and Conditions of Sale, which control unless it agrees otherwise in writing. Any existing intellectual/industrial property rights must be observed. Due to possible changes in our products and applicable national and international regulations and laws, the status of our products could change. Material Safety Data Sheets providing safety precautions, that should be observed when handling or storing Clariant products, are available upon request and are provided in compliance with applicable law. You should obtain and review the applicable Material Safety Data Sheet information before handling any of these products. For additional information, please contact Clariant.® Trademark of Clariant registered in numerous countries.

* For sales to customers located within the United States and Canada the following applies in addition: NO EXPRESS OR IMPLIED WARRANTY IS MADE OF THE MERCHANTABILITY, SUITABILITY, FITNESS FOR A PARTICULAR PURPOSE OR OTHERWISE OF ANY PRODUCT OR SERVICE.

© 2014 Clariant International AG, Rothausstrasse 61, 4132 Muttenz, Schweiz ® Product and service marks protected by Clariant

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