Filler wetting

Ester plasticizers are used mainly in very polar elastomers, such as neoprene and nitrile mbber, to improve low or high temperature performance or impart particular oil or solvent resistance to a compound 5—40 parts are commonly used (see Plasticizers). Resins and tars are added to impart tack, soften the compound, improve flow, and in some cases improve filler wetting out, as is the case with organic resins in mineral-filled SBR. Resinous substances are also used as processing agents for homogenizing elastomer blends. 

First, a homogeneous suspension of filler must be produced. This suspension should be sedimentation-lfee because it would influence foam properties. Rheological studies are used to select the appropriate dispersion agents which keep the viscosity close to the viscosity of the unfilled formulations. Complete filler wetting and network formation helps to make the stable suspensions. 

Loadings can be increased by adding a diluent, but this may not always be desirable, as the diluent may detract from other desired properties. Organo titanates can be added to improve filler wetting, enabling higher loadings at the same viscosity. 

Unaccelerated, with good filler wetting properties, suitable for cold-press moulding. 

A marble/onyx casting resin of good colour, offering excellent filler wet-out and fast gel in the production of sinks and flat stock, c. 1250 e. 19/25... 

An unaccelerated UV stabilised orthophthalic offering good filler wet-out properties in the manufacture of polymer concrete. ... 

---