ANIONIC-POLYMERIZATION OF ACRYLATES .10. SYNTHESIS AND CHARACTERIZATION OF BLOCK-COPOLYMERS WITH ACRYLATE BLOCKS

Block copolymers poly(styrene)-block-poly(tert-butyl acrylate), poly(tert-butyl acrylate)-block-poly(2-ethylhexyl acrylate), and poly(tert-butyl acrylate)-block-poly(butyl acrylate) were prepared by a successive anionic polymerization at -60 degrees C. As initiators, butyllithium/lithium tert-butoxide 1:6 (mol/mol) and tert-butyl 2-lithioisobutyrate/lithium tert-butoxide 1:3 or 1:10 (mol/mol) complexes were used, in the mixed solvent toluene/THF 9:1 or 19:1 (v/v). Products were characterized by SEC, C-13 NMR, and DSC. The block character of poly(tert-butyl acrylate)-block-poly(2-ethylhexyl acrylate) was proved by the extraction test with hexane. Compared to corresponding homopolymers, all the block copolymers exhibit only a slightly broadened MWD, which documents the virtually negligible extent of self-termination under given experimental conditions.