Free radical copolymerization behavior of vinyl acetate with butyl acrylate in the presence of GeCl4 and BCl3

No alternating copolymers of vinyl acetate (VAc) and butyl acrylate (BA) were obtained by free radical copolymerization in the presence of GeCl₄ and BCl₃ (compared with the acrylic acid–vinyl acetate copolymerization system). By ultraviolet spectral analysis, it was concluded that both BCl₃ and GeCl₄ can form complexes with butyl acrylate. The BA–BCl₃ complex constants were determined by ¹H NMR; K_B=33·2 (25°C). The reason for the gel formation in the BA–Vac–BCl₃ copolymerization system was discussed. When vinyl acetate reacted with BCl₃, cationic polymerization probably occurred. A white gel product probably resulted from the polymerization of the BA–BCl₃ complex. © 1998 SCI.