"Synthesis and structural regulation of low vinyl polybutadiene-b-polyvinylpyridine block copolymers "

Abstract

A low vinyl polybutadiene (PB)-polyvinylpyridine （PVP） diblock copolymers (lvPB-b-PVP) with the same segment length of PB but different segment length of PVP and controllable molecular weight and its distribution was designed and synthesized using anionic polymerization method. The molecular structure of the polymer was analyzed by gel permeation chromatography and nuclear magnetic resonance spectroscopy. The results showed that the polydispersity index of the molecular weight was 1.09-1.21, where the mole fraction of vinyl was 10.4%-11.5%, number-average molecular weight of low vinyl PB was 5.0 kg/mol, number-average molecular weight of PVP was about 5-30 kg/mol, and number-average molecular weight of the block copolymer was 10-35 kg/mol. This polymer was expected to has certain potential application value in self-assembly. Because the hydrogen bonding ability of P 2 VP and P 4 VP in the polymer was significantly different, the retention time of gel permeation chromatography of lvPB-b-P 2 VP shortened with the increase of its molecular weight, while the retention time of lvPB-b-P 4 VP was constant and the same as that of PB precursor.

Keywords

• vinyl pyridine
• butadiene
• block polymer
• low vinyl
• anionic polymerization
• structural regulation