Study On The Properties Of Chlorinated Polyvinyl Chloride And Chlorinated Polyvinyl Chloride/Polyvinyl Chloride Blends

Chlorinated polyvinyl chloride(CPVC)resin is a modified product from polyvinyl chloride (PVC) resin. The mechanical properties of CPVC resin, especially the thermal resistance, solubility, chemicals resistance, electrical property and flame retardance, are better than those of PVC resin. Now, CPVC resin has been wildly researched and applied, such as water-pipes, coatings, foam, CPVC composites, electric elements, CPVC/PVC blends and CPVC/ABS blends.In this paper, the rheological behaviors of CPVC resin and the CPVC/PVC blends are studied. The mechanical properties and micro-structures of CPVC/PVC blends are investigated. It is expected to demonstrate a theoretical and practical foundation for application of the CPVC/PVC blends. The Congo Red test and thermo gravimetric analysis (TGA) are used to study the thermal stability of the CPVC/PVC blends. Meanwhile it is focused on the effects of lead salt stabilizer and organic tin stabilizer on the CPVC/PVC blends.In the research of the rheological behaviors, it is founded that as CPVC resin is easy to be fused with the high contents of chlorine, the fusion time will not be reduced with the additives. But the additives have the effect on decreasing the torque. In the composites of PVC/CPVC blends, as CPVC content increases, the fusion time decreases and the torque increases; these phenomena show that CPVC has good fusion behavior.In the composites of PVC/CPVC blends, the fusion time decreases as the contents of CPE increase. But in the additive system of KM355P, the fusion time increases in turn, and the absolute value is higher than the former one. In the composites of CPVC with lead salt as stabilizer, the dosage of paraffin is lower than the composites of CPVC with organic tin as stabilizer for the metal soap stabilizer possesses the lubricating property. As KM355P is added as toughing agent, the composite of CPVC has good rheological behavior, the dosage of paraffin in the composite of CPVC with lead salt as stabilizer is lower than the composite of CPVC with organic tin as stabilizer.As the content of CPVC resin increases, the yield strength, tensile strength,bending strength and heat deformation temperature of CPVC/PVC blends have been improved. But impact strength and elongation at break decrease.The toughing agents, in the order of B-564, BTA-751, KM355P and CPE, can improve the impact strength of the blends. The SEM photographs of cross-section of samples not only can explain the results of impact experiment, but also prove the inner effect of microstructure on the strength properties of materials.As toughing agent of B-564 increases, the yield strength, tensile strength, bending strength and impact strength increase, but the thermal resistance is unvaried. When B-564 content reduces to 3 phr, the impact strength of PVC/CPVC hardly changes. As it content increases to 6 phr, the impact strength of the blend increases from 4.9kJ/m2 to 8.2kJ/m2. When it content increases to 8 phr, the impact strength increases to 14.4kJ/m , which is twice than the composite without B-564.As the content of CaCCh increases, the yield strength, tensile strength, bending strength and elongation at break decrease, especially the tensile strength decreases in high extent when the content of CaCOa increases to 10 phr. The heat deformation temperature has nearly no change when the content of CaCC?3 increases from 5 to 15 phr, but when it increases up to 15 phr, the heat deformation temperature increases. The addition of CaCCb has no effect on the tensile strength. So the CaCC?3 is better to use from 5 to 10 phr.In the research of thermal stability by the Congo Red test and thermo gravimetric analysis (TGA), it is found that CPVC has good effect on improving the stability of PVC, the lead salt stabilizer has better effect than organic tin stabilizer.The research on the CPVC/PVC blends is meaningful in obtaining novel polymer materials.