Polimerización radical viviente de mirceno a través del proceso RAFT

Abstract

"Monomers from renewable sources, such as terpenes, have become a focus of interest for polymer chemistry. Myrcene, a single monoterpene was quite polymerized in this work through the technology of reversible addition-fragmentation chain-transfer polymerization (RAFT) in bulk, using for the first time the chain transfer agents (CTA). The polymerization systems were carried out at temperatures of 65°C and 90°C varying the initiator / CTA ratios for each of the dithiobenzoates. The polymerizations made to measure a kinetic of pseudo first order with a linear growth of the molar masses with respect to the conversion, with a range of polydispersity (PDI) between 1.29 to 4.41 with the polymerizations at 90°C which are major PDI for both CTAs. The conversion values were low in comparation with its analogous polymerizations by free radicals, but with the large difference of polymyrcene by RAFT it acquired a characteristic color of the CTA and the absence of some type of cross-linking. The study of NMR microstructure of the polymer showed 91% of the 1,4 addition with the coexistence of its cis and trans isomers. The extension of the polymer chain with styrene by RAFT polymerization was carried out as a macro chain transfer agent to the polymyrcene synthetized previously by RAFT resulting in a block copolymer wich maintained a low polydispersity. The formation of copolymer confirmed the ends of the dithiobenzoate chain of the polymyrcene used."