New unsaturated surfactants for the dispersion polymerisation of methyl methacrylate in supercritical carbon dioxide

This paper describes the synthesis of a siloxane based stabiliser by ring o pening metathesis polymerisation of (bicyclo[2.2.1]hept-5-en-2-yl)triethoxy silane using Ru(PCy3)Cl-2(CHPh) as the initiator. The resulting polymer was then used as a stabiliser for the free radical polymerisation of methyl me thacrylate in supercritical carbon dioxide (scCO(2)). The poly(methyl metha crylate) (PMMA) formed using poly((bicyclo[2.2.1]hept-5-en-2-yl)triethoxysi lane) has high molecular weight and a narrow polydispersity. Under optimise d conditions of dispersion polymerisation in scCO(2), discrete spherical pa rticles of PMMA are formed with an average diameter of 2.7 mum. (C) 2001 El sevier Science Ltd. All rights reserved.