PVA/PVP共混物的SAXS研究

聚乙烯醇(PVA)/聚吡咯烷酮(PVP)共混物的小角X-射线散射(SAXS)研究表明,PVA/PVP共混物的结构参数与共混物组分比及热历史密切相关。按Vonk一维电子密度相关函数法,得到PVA/PVP共混物的长周期,过渡层厚随PVP组分含量增加而增加;结晶片层厚和比内表面积却随PVP含量增加而降低。热处理可提高共混物的结晶性。

STRUCTURAL STUDIES OF POLY (VINYL ALCOHOL)/POLY (VINYL PYRROLIDONE) BLENDS

The structures of poly (vinyl alcohol) (PVA)/Poly (vinyl pyrrolidone) (PVP) blends with different compositions prepared by solution casting method were investigated by Small Angle X-Ray scattering (SAXS). Results indicated that the structural parameters of the blends were deeply dependent on both compositions and crystallization conditions. According to one dimension electron density correlation function proposed by Vonk and the concept of pseudo two-phase strutural model, we obtained that the long periods and the thichnesses of transition layer increased with increasing the content of PVP in PVA/PVP blends while crystallinity, thicknesses of crystal lamellae of PVA/PVP blends and spcific inner surface decreased. Annealing process made the crystallinity strengthen obviously. The density difference of crystalline and .amorphous regions were about 0.005 g/cm2 at all the ratios of compositions.