Elastomer main ingredients

This book is studying the castable family of polyurethanes. The cured polyurethane elastomer is made from three main ingredients that are detailed in Table 2.1. 

All silicone elastomers have high thermal stability. When heated, they do not release toxic products and are used as main ingredients in the production of rubber compounds and heat-resistant rubbers. 

Fogging is associated with soft trim the main ingredients are volatile PVC plasticizers (now being replaced by polymeric plasticizers) and products resulting from the interaction between PU and PVC. However lubricants and flame retardants have also been identified. The biggest area is the seat covers, but because of its temperature the instrument panel has been identified as the main source. The elastomers in mats, gaskets and gaiters also contribute. 

A term applied to compounding ingredients, mainly antioxidants, which inhibit premature degradation of elastomers. 

For the reaction of TDI with a polyether triol, bismuth or lead compounds can also be used. However, tin catalysts are preferred mainly because of their slight odor and the low amounts required to achieve high reaction rates. Carboxylic acid salts of calcium, cobalt, lead, manganese, zinc, and zirconium are employed as cocatalysts with tertiary amines, tin compounds, and tin—amine combinations. Carboxylic acid salts reduce cure time of rigid foam products. Organic mercury compounds are used in cast elastomers and in RIM systems to extend cream time, ie, the time between mixing of all ingredients and the onset of creamy appearance. 

Several elastomers can be used in rubber-based adhesives. The elastomer provides the backbone of the adhesive, so the main performance of the adhesive is provided by the rubber properties. However, several specific properties for application are imparted by adding other ingredients in the formulations. The most common elastomers used in rubber-based adhesives are natural rubber (NR), butyl rubber (BR) and polyisobutylenes, styrene-butadiene rubber (SBR), nitrile rubber (NBR) and polychloroprene rubber Neoprene) (CR). 

Rubbers (or elastomers) are used mainly as floor coverings and membranes. Rubber flooring containing chlorine-based ingredients are not recommended because of the hazards involved. However, in most cases it is not true for other rubber types ethylene propylene diene (EPDM) rubber is recommended by the Danish Environmental Protection Agency as an alternative to PVC. 

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