The Control Research Of Crosslinking Toughening Structural On PPS/PMVS

Differential scanning calorimetry and polarized optical microscopy methods were used to investigate the crystallization behavior and crystallization kinetics of poly(phenylene sulfide)(PPS)/poly(dimethyl vinylmethylsiloxane)(PMVS)and PPS/PMVS/Si02 composites.In this article,the influences of PMVS and Si02 on PPS crystallization behavior are explained.Non isothermal and isothermal crystallization show that the PMVS and PMVS/Si02 can accelerate remarkably the crystallization rate of PPS due to heterogeneous nucleation effect.By the Differential Scanning Calorimeter Measurement(DSC)and rheological approach,the structure of the formed crosslinking network was explored.Crosslinking structure,formed in the PPS and its blends at 360?higher than the melt point of PPS,which makes it possible for the long-chain network be reserved in the melt of PPS and its blends and to act as a rheological modifier and a nucleation agent for PPS.Herein,by a rheological approach,a transition from the liquid-like to solid-like viscoelastic behavior was observed for the melt of PPS,PPS/PMVS and PPS/PMVS/Si02,and a frequency-independent loss tangent at low frequencies appeared at the gel point,revealing the formation of crystallite network.The results indicate that the network are not formed by heterogeneous crystallites connected directly with each other or by bridging molecules,but by the interparticle polymer chains which are significantly restrained by the cross-linking effect of PPS.Besides,the increase of nuclei density for the blends containing PMVS and PMVS/Si02 was estimated from POM observations.The result of an enhanced nucleation but an unchanged overall crystallization rate reveals the confining effect of the crosslinking network on PPS crystallization.This confining effect can be ascribed to the restrained diffusion ability of chains owing to the crosslinking network.