Characteristics of our products

POLYMER ST AND TEGOPAC®

Variable product design

Thanks to the wide choice of raw materials available on the market, to the flexibility in their design, Polymer ST polymers have the latitude to cover many different applications where their broad range of rheological and mechanical properties is needed. Based on a different production process, Evonik’s TEGOPAC® silylated polymer technology allows to tailor-make the polymer backbones. The construction of the polymer is not limited to PPG backbones as for current market products; here, new structural elements can be included. This opens-up completely new polymer properties (e.g. hydrophilicity/hydrophobicity balance, resistance against external aggressions). Additionally it is possible to adjust the location and the density of crosslinking groups on the polymers. With this new type of silane-modified polymers, formulators can produce formulations to address almost any type of application and obtain the best performance.

Environment and health friendliness

With the right selection of their ingredients, formulations based on Polymer ST and on TEGOPAC® require no danger sign under current legislation in all countries.

Elastic recovery

The elastic recovery of a material describes its ability to revert to its original shape after a deformation. This property is very important for sealants and for flexible adhesives which are used in applications where high variations of dimensions can take place. Polymer ST and TEGOPAC® silane-modified polymers can be formulated to show high elastic recovery and be applied in most demanding applications.

Curing performance

Moisture - curing materials first start to build a surface skin when in contact with air moisture. Once the skin is formed, the curing process continues in depth. However, the cure rate of one-component systems tends to slow down as the joint depth increases. Therefore complete cure of bulky materials can be a lengthy process, which in turn, delays the use of the sealed parts.

TEGOPAC® polymers show an improved in depth-curing performance in comparison to products on the market. Unlike epoxides, the curing process of silane-modified polymers is not significantly exothermal.

Over-paintability

A formulation or resin is claimed to be over-paintable when it allows good adhesion of one or more coatings on its surface, without negative influence on its properties.
Formulations based on Evonik Polymer ST and TEGOPAC® Silane-modified polymers are over-paintable by coatings used in most current applications.

Adhesion

By an individual design of the polymer backbone and the crosslinking points it is possible to develop silane-modified polymers which show improved adhesion properties on different substrates (e.g. plastics, metal, concrete, or wood).

In general silane-modified polymers show big advantages in applications where the material is applied onto humid substrates: polyurethanes normally show adhesion problems on humid surfaces and a bubble formation in e.g. adhesives/sealants.

UV-resistance

Many resins/elastomers show a change in their mechanical properties and/or their aspect after exposure to UV radiation. Because they can be better protected against UV than standard PU’s, Polymer ST silane-modified polymers show a clearly improved UV-resistance. In addition, thanks to their urethane linkage-free structure, TEGOPAC® polymers have a better inherent UV resistance.

Water resistance

The TEGOPAC® polymers of Evonik behave significantly better than other silylated polymers when immersed into either ambient or boiling water. The joints show a much better retention of their adhesion performances after this test.

 

Polymer ST

TEGOPAC®

PU

Silicone

Acrylate

Recovery from stress

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•••

•••

UV Resistance

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•••

•••

••

Low Temperature gunnability (5°C)

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•••

•••

•••

Over-paintability

•••

•••

•••

---

•••

Non-bubbling

•••

•••

---

•••

•••

No residual tack

•••

••

•••

•••

For inside & outside use

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•••

Universal adhesion

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•••

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•••  = strong      ••  = medium       • = weak      --- = not available   PU = Polyurethane