Polydimethylsiloxane Oligomers Research Articles

Inhibited oxidation of polydimethylsiloxane in the presence of transition metal compounds

The oxidation of polydimethylsiloxane oligomer, “liquid PMS-300” at 285–315°C in the presence of oxidation inhibitors, namely basic ferric caproate and the organosiloxy vanadates has been studied. The main kinetic features of the PMS-300 inhibited oxidation can be explained on the basis of a branched chain oxidation model. The inhibition capacity of the ferric caproate has been found to be used up by the oxidation and longer duration of inhibition is due to the low critical concentrations and to low rates of initiation of the polydimethylsiloxane oxidation.

Polysulfone–polydimethylsiloxane block copolymers

AbstractAlternating block copolymers have been synthesized from dihydroxyl‐terminated polysulfone and bis(dimethylamine)‐terminated polydimethylsiloxane oligomers. The products are soluble, amorphous, and transparent, and display excellent thermal and hydrolytic stability. Elastomeric and rigid compositions can be prepared by varying oligomer molecular weight. Copolymers made with oligomers of ≥ 5000 molecular weight are two‐microphase systems which display glass transition temperatures at −120°C and at +160°C, and therefore have a wide useful temperature range.