Squalene as a Natural Rubber Model Compound to Synthesize ATRP Initiator

Squalene was used as a natural rubber model compound to synthesize ATRP initiator by epoxidation to obtain epoxidized squalene (ESq) and then ring-opening reaction with 2-bromo-2-methylpropionic acid to synthesize bromoalkyl-functionalized squalene (ESq-Br). The structures of ESq and ESq-Br were characterized by FT-IR and 1H-NMR, and by combining with GC-MS and 13C-NMR the distribution of the functional groups such as epoxy group and bromoalkyl-functionalized unit, were analyzed. Results showed that three epoxy structures were involved in ESq, and its distribution was uniform. The ring-opening reaction happened along with side reactions such as the rearrangement of epoxy group, and from the distribution of residual epoxy group that the bromoalkyl-functionalized unit (i.e. the initiating point) distributed uniformly.