Block copolymers based on 2-methyl- and 2-phenyl-oxazoline by metallocene-mediated cationic ring-opening polymerization: synthesis and characterization†
Abstract
Previous studies have shown that the cationic polymerization of oxazolines, lactones and vinyl ethers can be efficiently promoted by metallocene complexes activated by floroaryl borates. Taking this into account, different series of block copolymers, i.e. PPhOx-b-PMeOx, Pε-CL-b-PMeOx, Pε-CL-b-PPhOx, PEVE-b-PPhOx, along with the triblock terpolymers, Pε-CL-b-PMeOx-b-PEVE and Pε-CL-b-PPhOx-b-PEVE, were prepared by sequential addition of monomers. The synthesis was monitored by SEC and NMR spectroscopy, showing that well-defined products are obtained in most cases. The microphase separation of the samples was studied by DSC and their thermal stability by TGA measurements.