POE-g-MA对纳米CaCO_3/聚乳酸复合材料热及流变性能影响

以纳米碳酸钙(Nano-CaCO_3)和聚乳酸(PLA)为原料,马来酸酐接枝乙烯-辛烯共聚物(POE-g-MA)为增容剂,利用熔融挤出热拉-骤冷工艺制备了一系列Nano-CaCO_3/PLA复合材料。分别采用SEM、DSC、TG、毛细管流变仪(CR)和万能实验机研究了Nano-CaCO_3/PLA复合材料的界面相容性、热性能、流变性能与力学性能。结果表明:与纯PLA相比,当Nano-CaCO_3含量达到15wt%,Nano-CaCO_3/PLA复合材料团聚现象明显,其结晶度、最大热分解温度与拉伸强度分别下降1.9%、15.5℃与28.2%,弯曲强度和断裂伸长率分别提高37.5%和29.3%,而相应添加4wt%POE-g-MA增容剂的Nano-CaCO_3/PLA复合材料分散形态得到改善,其结晶度和拉伸强度分别下降4.2%和25.2%;最大热分解温度、弯曲强度和断裂伸长率分别提高5.8℃、25.3%和174.4%;同时POE-g-MA增加了Nano-CaCO_3/PLA复合材料的剪切黏度。

Influences of POE-g-MA on thermal and rheological properties of Nano-CaCO3/PLA composites

The nanometer calcium carbonate (Nano-CaCO3 )/polylactic acid (PLA)composites was melt-compoun-ded by twin-screw exturder with Nano-CaCO3 and PLA as raw materials,maleic anhydride grafted ethylene-octene copolymer (POE-g-MA)as compatibilizer.SEM,DSC,TG,capillary rheometer (CR)and universal testing ma-chine were used to perform the interfacial compatibility,thermal properties,rheological properties and mechanical properties of Nano-CaCO3/PLA matrix composites,respectively.The results show that the aggregation phenome-non in the PLA matrix increases compared with pure PLA when the content of Nano-CaCO3 increases to 15wt%. The crystallinity,the maximum thermal decomposition temperature and the tensile strength of Nano-CaCO3/PLA composites decrease by 1.9%,15.5 ℃ and 28.2%,the flexural strength and elongation at break increase by 37.5%and 29.3%,respectively.And the interfacial compatibility of Nano-CaCO3/PLA composites with 4wt% POE-g-MA improves,the crystallinity and the tensile strength of sample decrease by 4.2% and 25.2%,the maximum thermal decomposition temperature,the flexural strength and elongation at break of sample increase by 5.8 ℃,25.3% and 174.4%,respectively.The shear viscosity of Nano-CaCO3/PLA composites increases due to thaddition of POE-g-MA.