硬质交联PVC泡沫塑料的制备

Preparation of Rigid Cross-Linking PVC Foam Plastics

以聚氯乙烯（PVC）为基体，马来酸酐为接枝剂，异氰酸酯、三聚氰胺为交联剂，制备出性能优异的硬质交联PVC泡沫塑料；通过红外光谱、热失重和热机械分析及凝胶含量测定对硬质交联PVC泡沫塑料进行分析，证实交联反应发生在水煮工艺阶段，玻璃化转变温度在180℃左右；研究了马来酸酐用量对硬质交联PVC泡沫塑料凝胶含量的影响，马来酸酐的用量在塑化成型阶段对交联度的影响较小，硬质交联PVC泡沫塑料的凝胶含量随着马来酸酐用量的增加而增大；用光学显微镜对硬质交联PVC泡沫塑料的泡孔直径进行了测量。结果表明，硬质交联PVC泡沫塑料的泡孔直径分布较为均匀，密度为60kg／m^3的泡孔直径主要分布在100～130μm，密度为90kg／m^3的泡孔直径主要分布在70～80μm；测定了硬质交联PVC泡沫塑料的力学性能，结果显示，其具备同瑞士Airex C70产品相当的力学性能。

Based on polyvinyl chloride（PVC） resin, rigid cross-linking PVC foam plastics with special performance were prepared by isocyanate and melamine which were used as the cross-linking agent and maleic anhydride which was used as the grafting agent. It is confirmed that the cross-linking reaction happen in the boiling process phase by infrared spectrum analysis, thermal gravimetric analysis, thermal mechanical analysis and gel content measurement. It also shows that the glass transition temperature of the foam plastics is at about 180℃. Dosage of maleic anhydride was studied on the influence of the gel content of the foam plastics, the amount of maleic anhydride has less effect on the degree of cross-linking in plasticization and molding phase and the gel content of the foam plastics is increased with the increase of dosage of maleic anhydride. Bubble pore diameter were measured by optical microscope. It shows that the distribution of bubble pore diameter are homogeneous, the bubble pore diameter of the foam plastics for the density of 60 kg/m^3 are mainly distributed in 100 - 130 μm and the density of 90 kg/m^3 are mainly distributed in 70-80 μm. By the determination of the mechanical properties of the foam plastics, it shows that the foam plastics has the same mechanical properties as the Swiss Airex C70 products.