Study On Properties Of CPVC For Heat Resistant Chemical Pipeline

In this paper, both physical blend and chemical grafting methods were used to modify CPVC resin. The mechanical properties, processability, heat resistance as well as analysis of section micrograph and dynamic mechanical properties of different modified system has been researched.Melt mixing method was used to prepared CPVC and its blends/composites system. The thermal stability and processsability were improved with the addition of thermal stabilizer, lubricant and processing aid.The physic mixing system was researched in the follow ways:1) The basic formular and processing conditions were researched. The result indicated that the well processing performance, excellent thermostablity and mechanical properties were obtained when the processing temperature is195C and the dosage of processing aid ACR is3phr.2) The effect of elastomer content on properties of blends was studied respectively. The result revealed that CPE could enhance the toughness of blending system remarkable. Meanwhile, the tensile strength and heat resistance declined. The addition of ABS could up-grade the toughness, strength as well as heat resistance of blending system. While the blending ratio of CPVC/ABS acheived100/12. the comprehensive properties could reach the max value. For lifting the compatibility further. SAN and MBS were added respectively. It turned out that MBS could improve the compatibility of CPVC and ABS. While the content of MBS is6phr. the mechanical properties could reach the max.3) It was studied the effect of inorganic particle content on properties of CPVC/SiO2and CPVC/MMT composites. It proved that the mechanical properties and heat resistance shows lift tendency with the content of nano-SiO2increasing. For CPVC/ABS/SiO2composite system, when the mass ration of CPVC/ABS/SiO2is100/12/2, the tensile strength, bending strength and notch impact strength of the system could reach the max value, the glass-transition temperature (Tg) and Heat Distortion Temperature (FIDT) gained a further enhancement.The chemical grafting system was researched as follows:CPVC-g-MMA or CPVC-g-BA which was composed of CPVC as backbone and Methl Methacrylate (MMA) or butyl acrylate (BA) as branched chains were prepared by suspension-swelling graft copolymerization. The effect of initiator and grafted monomer (BA or MMA) content on mechanical properties, processing performance and heat resistant of graft copolymer were researched. The result indicated that grated monomer BA or MMA could improve the processability. With the increasing of BA, the toughness of grafting was heighted obviously. After CPVC was grafted MMA monomer, the strength, toughness along with heat resistance received lifting. When the CPVC/MMA/BPO mass ration is100/15/1, the best comprehensive properties could be obtained. FTIR proved that CPVC-g-BA and CPVC-g-MMA graft system could be prepared by suspension-swelling graft.