表面改性纳米碳酸钙原位悬浮聚合PVC的制备与性能研究

Preparation of PVC resin by in-situ suspension polymerization with surface-modified nano-CaCO_3 and study on its properties

采用湿法表面改性的纳米碳酸钙(nano-CaCO3)与VCM原位聚合,制备了nano-CaCO3原位聚合PVC树脂(简称原位PVC树脂),研究了其力学性能、加工性能、微观形貌和热稳定性等。结果表明:①nano-CaCO3能够很好地分散在PVC树脂中,对PVC基体产生很好的补强作用;与普通PVC试样相比,原位PVC试样缺口冲击强度提高到13.3 kJ/m2,效果显著;其加工性能也得到了提高。②试样冲击断面的扫描电子显微镜照片表明原位PVC试样为韧性断裂,普通PVC试样为脆性断裂。③DSC试验表明,原位PVC树脂的热稳定性优于纯PVC树脂。

The nano-CaCO3 in-situ suspension composite PVC resin was prepared through the in-situ polymerization of VCM with nano-CaCO3 whose surface was modified by wet process, and its mechanical properties, processing properties, micromorphologies and thermal stability were stud- ied. The results show that： （1） Nano--CaCO3 is uniformly dispersed into PVC resin, reinforcing PVC substrate; compared with ordinary PVC samples, the notched impact strength of nano-CaCO3 in-situ suspension composite PVC resin is significantly increased up to 13.3 kJ/m2 , and its process- ing properties is also improved. （2） The SEM photographs of impact cross-section of samples show that the fracture of nano-CaCO3 in-situ suspension composite PVC samples is ductile fracture, and the fracture of ordinary PVC samples is brittle fracture. （3） DSC tests show that the thermal stabil- ity of nano-CaCO3 in-situ suspension composite PVC resin is better than that of pure PVC resin.