Dicumyl peroxide → Divinylbenzene-styrene

Participants

Reaction Steps

A crosslinked styrene-divinylbenzene fine particle product was prepared by polymerization of 30 g. styrene and 3 g. 55% divinylbenzene in 500 ml. hexane using 2.89 ml. of 2N S-butyllithium as catalyst and 1.5 g. of styrene-t-butylstyrene block copolymer of Example 4 as dispersant (20,000 - 80,000 M.W. blocks respectively) under nitrogen. At the end of 1 hour reaction at reflux the solution was treated with 3.0 ml. of dry, air free t-butylstyrene for 30 minutes followed by 2.0 g. of hexamethylcyclotrisiloxane in 5.0 ml. of tetrahydrofuran for 2.5 hours. This was followed by the addition of 1.26 ml. of allyldimethylchlorosilane. The resulting product was blended with 118 g. of dimethyl siloxane rubber (General Electric Co. No. SE-76) dissolved in hexane and the mixture precipitated into methanol to give a product containing 28 parts of filler particles per 100 parts of silicone rubber. This product was mixed with 2 parts of dicumylperoxide per 100 parts of silicone rubber and cured in a press at 135°C. for 35 minutes. The cured rubber had the following properties:

Provenance & Evidence