Polycondensation of diethyl mucate with hexamethylenediamine in the presence of poly(vinyl pyridine)

The polycondensation reaction of diethyl mucate (DEM) with hexamethylenediamine (HMD) was carried out in dimethyl sulfoxide (DMSO) at 60°C in the presence of poly(vinyl pyridine) (P‐VPy) as a matrix polymer, which was expected to interact with DEM or the resulting polyamide which had pendant hydroxyl groups due to a hydrogen bonding. It was found that the polycondensation of DEM with HMD in the presence of poly(4‐vinyl pyridine) (P‐4VPy) produced a polyamide with a higher molecular weight than those in the presence of poly(2‐vinyl pyridine) (P‐2VPy) or in the absence of P‐4VPy. The rate of the polycondensation, however, was rarely enhanced by polymer matrixes such as P‐4VPy and P‐2VPy. During polycondensation in the presence of P‐4VPy a gelation of the reaction mixture was observed when the solution was kept at 30°C for several days. This might be ascribed to the formation of the polymer complex between resulting polyamide and P‐4VPy during the polycondensation.