The Study Of Properties And Structure Of CPVC/ABS Blends

Chlorinated polyvinyl chloride (CPVC) is a significant engineer thermoplastic. For its excellent high temperature performance, resistance chemical corrupt, low heat conduction, and insulating property, CPVC is been used widely. While CPVC have some shortcomings, such as the poor impact strength and difficulties in processing, those factors limited the use of CPVC. The best way to toughen CPVC is introducing core-shell modifiers ABS. In this work, ABS was been synthesized by emulsion polymerization, and melt with CPVC, and the main works and the results as following:1. The core-shell modifiers ABS with two layers and MABS with there layers were been synthesized by emulsion polymerization. The miscibility between shell of modifier and CPVC, and the effect of modifier on the properties of CPVC were been investigated. The results showed:CPVC is immiscible with SAN resin, but miscible with PMMA resin; Compared to ABS, MABS have a better dispersion in CPVC, and get higher impact strength. The core-shell ratio of modifier influence the dispersion, and when the ratio is larger and smaller, modifier agglomerate in the CPVC. The impact strength of blends increased first and then decreased with the increase of core-shell ratio.2. The effect of PB particle size and the content in blend on the impact strength of CPVC/ABS blend was been studied. The bimodal system of ABS were been prepared by blending ABS1 and ABS5, ABS2 and ABS5, ABS3 and ABS5, and then used to toughened CPVC. The results indicated the impact strength of blends increased first and then decreased as increasing of PB particle size, the optimum size is 157nm. The impact strength of blend also increased and then decreased with the increase of PB content. The synergetic affect occur in the bimodal of ABS2/ABS5.3. The influence of the content of PVC, PB particle size on CPVC/PVC/ABS were been studied. The bimodal system of ABS was been prepared by blending ABS1 and ABS5, then used to toughened CPVC/PVC. The dynamic mechanical analysis showed that CPVC/PVC is partially miscible only when the ratio of CPVC/PVC is 90/10, and at other ratio they are immiscible; CPVC is immiscible with SAN resin, but partially miscible with grafted SAN in ABS. The morphology results showed that the dispersion of ABS in matrix is influenced by PB particle size, and ABS2 have a better dispersion in CPVC. The mechanical tests showed that the impact strength of blends have their maximum values, when the PB particle size of ABS impact modifiers is from 100 nm to 150 nm. There is obvious synergetic effect in the bimodal system. With the increase of PVC content, the impact strength of blends increased and then decreased, and the optimum ratio of ABS1/ABS5 in bimodal system decreased.