Poly(4-vinylbenzyl-g-β-butyrolactone) graft copolymer synthesis and characterization using ring-opening polymerization, free-radical polymerization, and “click” chemistry techniques

Abstract

The synthesis of poly(4-vinylbenzyl-g-β-butyrolactone) (poly(VB-g-BL)) graft copolymer was carried out by “click” chemistry of terminal azido poly(4-vinylbenzyl chloride) (PVB-N₃) and terminal propargyl poly(β-butyrolactone) (β-BL-propargyl). For this purpose, poly(4-vinylbenzyl chloride) (poly-4-VBC) was obtained using 4-vinylbenzyl chloride and 2,2′-azobis(2-methylpropionitrile) by free-radical polymerization. PVB-N₃ was synthesized using sodium azide and poly-4-VBC. β-BL-propargyl was obtained by the reaction of β-butyrolactone monomer with propargyl alcohol via ring-opening polymerization. The graft copolymer was also synthesized via “click” chemistry, employing PVB-N₃ and β-BL-propargyl. The products were thoroughly characterized by GPC, FT-IR, SEM, and ¹H-NMR. DSC and TGA were used to track the graft copolymer’s thermal characteristics. Thermal and spectroscopic measurements verified that the reactions were effectively completed.

Graphical abstract

Poly(4-vinylbenzyl chloride) was obtained by free-radical polymerization. Terminal azido poly(4-vinylbenzyl chloride) was synthesized using sodium azide and poly(4-vinylbenzyl chloride). Terminal propargyl poly(β-butyrolactone) was obtained by β-butyrolactone and propargyl alcohol via ring-opening polymerization. Poly(4-vinylbenzyl-g-β-butyrolactone) graft copolymer was synthesized by “click” chemistry. Thermal and spectroscopic measurements verified that the reactions were completed.