Research On Synthesis Of MAH-g-CPVC And Properties Of Its Blending Composites

Chlorinated polyvinyl chloride (CPVC) is the product obtained from thefurther chlorination of polyvinyl chloride (PVC). Because CPVC has a highchlorine content, its mechanical properties, heat resistance, chemical resistanceand weather resistance are better than PVC. Therefore, CPVC has broadlyapplication prospects in the field of hot and cold water pipes, high flameretardant cable sheath and high temperature wire. However, its poor thermalstability, viscosity, and poor processability have limited its applications. Themodification of CPVC becomes a hot spot in research. a new modificator ofCPVC grafted with maleic anhydride (MAH) is prepared, which has not beenreported before. Then the modifier is used in PVC to prepare a CPVC-g-MA/PVC blend to lay a good foundation for the application of CPVC.For the first time, the CPVC is modified by MAH, to obtain PVC/MAH-g-CPVC blend. Three kinds of grafting methods were studied to determine thefactors influencing the graft rate and the best grafting process. Then the thermalstability was tested and analyzed. The results show that the best method ofgrafting is solid grafting method. The optical formulation and process wereascertained. The weight ratio of MAH: ASP=20:3:0.4; The volume of acetone is50ml; The reaction temperature is80℃and reaction time is2h. The highestgraft ratio of MAH-g-CPVC is2.91%. Heat stability and reheological propertieswere tested and analyzed also.The composite was prepared by blending the MAH-g-CPVC modifier withPVC resin. Properties such as morphology, rheological properties, impactproperties, thermal conductivity, flame retardance etc. were analyzed. The resultsshowed that when the amount of MAH-g-CPVC in the composite is raised, thethermal stability and flame retardant properties of the composite are improved,the thermal conductivity and impact strength of the composite increase slightly, and the dispersibility of the system is improved. However, the rheologicalproperties of the composite gets worse gradually. When the amount of MAH-g-CPVC reaches25wt%, the comprehensive properties of the composite are at thebest, and rheological properties only changes a little.