Regulation of supramolecular additives on conformation and crystallization behaviors of syndiotactic polystyrene
Syndiotactic polystyrene(sPS)/N,N'-diphenylterephthalamide(DPHT)blends were prepared through melt blending,and the conformation and crystallization behaviors of sPS were regulated by utilizing the π-π interactions be-tween sPS and DPHT.The results indicated that there were two dispersion states for DPHT,i.e.,free molecule or as self-assemblies,existing in the sPS matrix.The addition of DPHT increased the content of the all-trans conformation(TTTT)of sPS and reached a maximum when the self-assemblies were formed for DPHT.Moreover,the self-assem-bled structures of DPHT effectively increased the content of β-crystals in sPS.The proportion of the β-crystals was high-er than that of the α-crystals in the sPS/DPHT blends at a slow cooling rate of 5 or 2 ℃/min.However,the α-crystal content in sPS was higher when the cooling rate was increased to 10 ℃/min.When DPHT was molecularly dispersed in the sPS matrix,the π-π interaction between DPHT and sPS restricted the crystallization ability of sPS,resulting in a de-crease in the degree of crystallinity from 41％to 35.9％).When DPHT was in the self-assembly state,the self-assem-blies of DPHT acted as a nucleating agent to promote the crystallization of sPS,leading to an increase in the degree of crystallinity from 36.1％to 38.2％.Therefore,the conformation and crystallization behaviors of sPS were successfully regulated during melt processing through the π-π interactions between DPHT and sPS.
万方数据
维普
