Synthesis and characterization of bisester-amide segments of uniform and random length

With the uniform amide segments and polypropylene oxide segments, block copolymers were prepared by high temperature melt polymerization. The amide segment length distribution, which is susceptible to randomization was studied. The analysis of the amide segment distribution after hydrolysis of the ester-linkage groups was by MALDI-TOF. The amide segments were found to have the same narrow distribution as the starting bisester-oligoamide, which strongly supports the fact that randomization of the amide segments during melt polymerization does not take place. The uniformity of the amide segments is, therefore, preserved during high temperature melt polymerization.