adhesives and sealants

Sealants and AdhesivesProduct portfolio

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Base polymers for condensation curing silicones •Polymer OH•Polymer OR 501•Polymer OM page 4

Crosslinkers for condensation curing silicones •Crosslinker OX•Crosslinker AC•Crosslinker K page 7

Modifier OH - reactive plasticizers •For non-bleeding silicone sealants for electronic applications, natural stone, etc.•Almost infinitely variable degree of hardness page 11

Tin catalysts •Catalyst TL 16•Catalyst TD 18 page 12

This product portfolio comprises various high quality base materials for highly elastic one-component sealants. These sealants are used for bonding and sealing joints on arange of substrates including glass, plastics, ceramics, concrete, aluminum and copper.

About UsEvonik, the creative industrial group from Germany, is one of the world leaders in specialty chemicals. Its activities focus on the key megatrends health, nutrition, re-source efficiency and globalization. Evon-ik benefits specifically from its innovative capability and integrated technology plat-forms. We apply our creativity daily to new, future-oriented solutions, aligning ourselves to future markets with highly promising growth dynamics, and develop-ing essential and indispensable solutions for our customers.

The broad range of products offered by Evonik Hanse GmbH reflects the exten-sive variety of requirements specified by our customers. For more than 20 years we have led the way with trail-blazing re-search while constantly monitoring the latest trends in various industrial sectors. Always a step ahead of market develop-ments, we offer you solutions to tomor-row’s application requirements – today.

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Base polymers for condensation curing silicones

Evonik Hanse offers 3 different base poly-mers for adhesives and sealants:•Polymer OH•Polymer OR 501•Polymer OM

Polymer OH are polydimethyl siloxanes with terminal silanol groups used as base polymers in condensation curing silicone elastomers. Polymer OH is available in

different viscosity levels between 80 and 400,000 mPa∙s. Other viscosities are possible upon request. Please note that Polymer OH 0,08 acts as an inhibitor and

can therefore be used for delaying the curing process.

Polymer OH – Hydroxy-Terminated Polydimethylsiloxanes

Technical data

Product nameViscosityat 25°C [mPa∙s]

Polymer OH 0,08 80

Polymer OH 0,75 750

Polymer OH 1 1,000

Polymer OH 2 2,000

Polymer OH 3,5 3,500

Polymer OH 5 5,000

Polymer OH 10 10,000







ApplicationPolymer OH can be cured with usualcondensation crosslinkers such as alkoxy silanes, acetoxy silanes (Crosslinker AC), oxime silanes (Crosslinker OX) and enoxy silanes (Crosslinker K) in connection with catalysts (e. g. tin catalysts, Catalyst TD 18). Especially the low-viscosity types can be used as reactive diluents for the viscosity adjustment in a mixture with higherviscosity polymers.

The crosslinking reaction starts on con-tact with water. In conventional single-component formulations, this water can be introduced through the humidity. However, Polymer OH can also be for-mulated as two component systems. In this case, the required water is added through the second component. Substan-tially higher curing rates and depths are achieved in this way.

ApplicationEspecially the field of marble and natural stone applications involves the risk ofsilicone oils being absorbed by thesefine-pored substrates (“blotting-paper effect”). This produces discolorations in the edge zones of the glued joint which may be worsened by adhering dust. This effect can be avoided by using Polymer OR 501.

Polymer OR 501 is also suitable forapplications in the electronics industry as free silicone oils may have a negative effect there as well.

In formulations, Polymer OR 501 substi-tutes the base polymer (hydroxyl-termi-nated siloxane) and the silicone plasticizer. Curing of these polymers is achieved by

using common condensationcrosslinkers such as Crosslinker OX, Crosslinker AC, and Crosslinker K.

Polymer OR 501 is a special siliconepolymer for non-staining condensation-curing silicone formulations. This polymer is recommended in particular for low-modulus sealants and adhesives when the use of silicone oils as plasticizers is not advised, e. g. in natural stone applications.

Polymer OR 501*

Technical data

Property Unit

Viscosity (25°C) [mPa∙s] 50,000

Appearance clear, colorless liquid

* not available in the USA

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ApplicationPolymer OM can be formulated with the typical additives for condensation-type silicones (tin catalysts, silane-based adhe-sion promoters, plasticizers etc.). The amount of methoxy silane crosslinkers can be reduced to a great extent in this process as the polymer already carries the corresponding methoxy silane groups.

Polymer OM are ready-for-processing silicone polymers for producing neutral condensation-curing silicone sealing compounds. After adding a suitable cata-lyst (e. g. organotin or organotitanium compounds) these polymers are mois-ture-curable. During the curing process methanol is liberated.

As methanol is non-corrosive, sealing compounds based on Polymer OM can also be used on sensitive or corrodible substrates such as metals and/or marble.

Polymer OM – Alkoxy-Functionalized Silicone Polymers

Technical data

Produkt nameViscosityat 25°C [mPa∙s]

Polymer OM 53 45,000

Polymer OM 23 18,000

Polymer OM 5 4,500

Polymer OM 1 800

Crosslinkers for condensation curing silicones

Evonik Hanse offers 3 types of cross-linkers for condensation-curing silicones:•Crosslinker OX Oxime silanes•Crosslinker AC Acetoxysilanes•Crosslinker K Enoxysilanes

ApplicationCrosslinker OX is used in sealants, usually at concentrations between 4 and 6 wt%. The various Crosslinker OX differ by their reactivity, with the general rule being:TOS > VOS > MOS

Mixing different Crosslinker OX types enables setting the rate of a formulation precisely, i. e. skin-over time, curing rate and time to first elastic recovery.

Crosslinker OX are oxime silane-based crosslinkers for producing neutral mois-ture-curing silicone sealants. Using these silane compounds, hydroxy-functionalized silicone polymers are crosslinked to ob-tain a silicone elastomer under the effect of a catalyst and moisture. When using Crosslinker OX, no acetic acid or amine is released in contrast to acid or alkaline

crosslinking systems, but 2-butanoneoxime. As this cleavage product reacts neutrally, sealing compounds based on Crosslinker OX can be used even on sen-sitive substrates such as marble.

Crosslinker OX – Standard Oxime Silanes

Technical data

Product name Composition

Crosslinker OX 10 MOS

Crosslinker OX 20 VOS

Crosslinker OX 30 TOS/Toluene 50/50

Crosslinker OX 32 VOS/TOS 65/35

Crosslinker OX 33 VOS/TOS 82/18

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Technical data

Product name Composition

Crosslinker OX 81* Mixture of methyl functionalized silanes

Crosslinker OX 82* Mixture of vinyl functionalized silanes

Crosslinker OX 91* Mixture of methyl functionalized silanes

These Crosslinkers are modified oxime silanes being used for classification-free, moisture curing, neutral silicone sealants. Using these silane compounds, hydroxy-functionalized silicone polymers are crosslinked to obtain a silicone elastomer

under the effect of a catalyst and mois-ture. As the cleavage products react neu-trally, sealing compounds based on these crosslinkers can be used even on sensi-tive substrates such as marble.

ApplicationCompared to standard oxime silanes dur-ing processing 35-55% less MEKO are re-leased, depending on the specific formu-lation. Using low MEKO Oximes it is possible to formulate filled as well as un-filled systems with a free MEKO content of less than 1%.

A total dosage of 5% Crosslinker OX is recommended. The reactivity of the sys-tem (e.g. skin-over time) can be adjusted by combining different grades of Cross-linker OX.

Crosslinker OX 81 has a low reactivity. It can be partially or fully replaced by Crosslinker OX 82 to gradually increase the reactivity of the system.

Crosslinker OX 91 has a similar reactivity as OX 81. It can be accelerated by replac-ing up to 1.5% by the standard oxime Crosslinker OX 20 without compromising the low MEKO requirement.

Crosslinker OX – Low MEKO Oxime Silanes Crosslinker AC – Acetoxy SilanesCrosslinker AC are crosslinkers for pro-ducing moisture-curing silicone sealants. Using these silane compounds, hydroxy-functionalized silicone polymers (Poly-mer OH) are crosslinked to obtain sili-cone elastomers under the effect of a catalyst and moisture.

Evonik Hanse offers both pure acetoxy silanes which can be employed either in pure form or in mixtures with other com-ponents and mixtures of different acetoxy silanes which can be used directly in cor-responding formulations.

Technical data

Product name Chemical Characterization Composition

Crosslinker AC 10 Ethyl triacetoxy silane ETAS

Crosslinker AC 15 Methyl and ethyl triacetoxy silane mixture

MTAS/ETAS 30/70

Crosslinker AC 30 Methyl triacetoxy silane MTAS

AC 10 (lowest reactivity) < AC 15 < AC 30 (highest reactivity)

Technical data

Product name Chemical Characterization

Crosslinker K 10 Tris(isopropenyloxy)silane

Crosslinker K is based on enoxysilanes, i. e. silanes that cleave acetone during crosslinking. Acetone is volatile, non-cor-rosive and has a low odor. These silanes are used in electronic and cleanroom ap-plications as they are not being absorbed on silicon wafers as e.g. oximes. More-over acetone is not a VOC in the US, al-lowing for low-VOC-formulations.

Enoxy cured silicones have a particular ad-vantage when being used in closed com-partments at elevated temperatures. Con-trary to oxime, alkoxy, acetoxy and similar systems they do not undergo a reversion reaction which may otherwise lead to a sof-tening or even liquefaction of the sealant.

ApplicationCrosslinker K 10 is used in sealants at a typical dosage of ca. 5% in combination with tin catalysts such as Catalyst TD 18.

Crosslinker K – Enoxy Silanes


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Modifier OH – Reactive plasticizers

Modifier OH are reactive silicone plasti-cizers for condensation systems containing both crosslinkable (hydroxy-functional) and unreactive chain ends. Modifier OH are therefore particularly suited for pro-ducing “non-bleeding” silicone sealants for marble/natural stone applications and for the electronics industry. Gel-like ma-terials can also be produced using Modifi-er OH.

Key properties•For non-bleeding silicone sealants for

electronic applications, natural stone, etc.•Almost infinitely variable degree of

hardness• Improvement in green strength

Technical data

Product nameViscosityat 25°C [mPa∙s]

Modifier OH 650 50,000

Modifier OH 655 5,000

Property profileModifier OH can be used in relatively high amounts as a reactive silicone plas-ticizer for the production of soft (low-modulus) silicone sealants, or for gel-like products. Using Modifier OH, the potential “bleeding”, i. e. the migration of plasticizers from the sealant to the substrate, can be prevented efficiently. Bleeding is well known with natural stone (granite, marble) in particular, due to the formation of dark edges along the joint. It should be emphasized that for-

mulations with Modifier OH exhibit an excellent early green strength, which is significantly improved compared to non-reactive silicone plasticizers.

ApplicationSilicone formulations using Modifier OH can be produced in the same way as other known polymer/plasticizer mixtures, i. e. by substituting a non-reactive plasticizer completely or partly by Modifier OH; if required, the base polymer may also be partly substituted by Modifier OH. De-pending on the percentage of Modifier

OH contained in a formulation, the Shore hardness can be adjusted over a wide range. Crosslinking of the reactive chain end of this modifier is by means of the condensation crosslinkers already present in the respective system.

ApplicationCatalyst TL 16 can be used to replacedibutyltin-based catalysts and may therefore be used for the production of non-hazardous formulations. It is fur-thermore approved for products with the eco-label “Der Blaue Engel”.

Due to its low yellowing tendency, Cata-lyst TD 18 is suited for use in transparent formulations based on silane-terminated polyurethanes (Polymer ST) or silane-terminated silicones (Polymer OM).

Catalyst TD 18 can be used to replacedibutyltin-based catalysts when non-hazardous formulations are required.

Catalyst TL 16 and Catalyst TD 18 areorganotin compounds for catalyzingsingle- and two-component condensation-curing systems.

Technical data

Product name Chemical characterization AppearanceMelting point[°C]

Density[20°C]

Catalyst TL 16* Dioctyltin dilaurate yellowish approx. 20 approx. 1.0

Catalyst TD 18* Dioctyltin carboxylate colorless to yellow

< 5 approx. 1.0

Tin catalysts


Asia | Pacific

Evonik Degussa Specialty Chemicals Co, Ltd. 55, Chundong Road Xinzhuang Industry Park Shanghai, 201108PR ChinaPhone +86 21 6119-1125 fax +86 21 6119-1406

The Americas

Evonik Goldschmidt Corp. 914 E. Randolph Rd. P.O. Box 1299 Hopewell, VA 23860USAPhone +1 804 541-8658 fax +1 804 541-2783

Europe | Middle East | Africa

Evonik Hanse GmbH Charlottenburger Straße 9 21502 GeesthachtGermanyPhone +49 4152 8092-0 fax +49 4152 [email protected] www.evonik.com/hanse

For more detailed information or to obtain a brochure which addresses a specific area of interest, please visit our website.

This information and all further technical advice is based on our present knowledge and experience. However, it implies no liability or other legal respon-sibility on our part, including with regard to existing third party intellectual property rights, especially pat-ent rights. In particular, no warranty, whether express or implied, or guarantee of product properties in the legal sense is intended or implied. We reserve the right to make any changes according to technological progress or further developments. The customer is not released from the obligation to conduct careful inspection and testing of incoming goods. Performance of the product described herein should be verified by testing, which should be carried out only by qualified experts in the sole responsibility of a customer. Reference to trade names used by oth-er companies is neither a recommendation, nor does it imply that similar products could not be used. (April 2008)

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