蒙脱土增强二聚酸改性不饱和聚酯树脂的制备及性能

Preparation and Properties of Unsaturated Polyester Resin Modified by Montmorillonite and Dimer Fatty Acid

分别通过原位聚合法和机械共混法,将含环氧基的有机蒙脱土(Organic montmorillonite,OMT)与C36二聚脂肪酸(Dimer fatty acid,DFA)改性不饱和聚酯树脂(Unsaturated polyester resin,UPR)结合,制备了OMT/DFA/UPR杂化材料和OMT/DFA/UPR复合材料。采用傅里叶红外光谱仪(FT-IR)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)表征材料结构、OMT分散程度、拉伸断面形貌及断面元素含量。研究发现,OMT通过化学键接枝到DFA/UPR主链上,且材料呈韧性断裂。通过热重分析仪(TG)、差示扫描量热仪(DSC)、拉伸、弯曲和硬度试验,研究了OMT添加量及添加方式对材料热稳定性和力学性能的影响。当OMT添加量为0.6%(质量分数)时,OMT/DFA/UPR杂化材料性能最佳,初始热分解温度、断裂伸长率、弹性模量及弯曲强度分别较DFA/UPR提高了11.3%、30.6%、88.7%和26.9%,而OMT/DFA/UPR复合材料除断裂伸长率提高了22.8%外,其余性能提高较少,甚至下降。

The OMT/DFA/UPR hybrid materials and OMT/DFA/UPR composites were prepared by in-situ polymerization and mechanical blending respectively,which were composed of organic montmorillonite(OMT)containing epoxy group and C 36 dimer fatty acid(DFA)modified unsaturated polyester resin(UPR).The material structure,dispersion degree of OMT,morphology of the tensile fracture surface,and elemental composition of the fracture surface were analyzed by FT-IR,XRD,SEM,and EDS.It was found that OMT grafted onto the DFA/UPR backbone by chemical bonds,and the material exhibited ductile fracture.In this study,the effects of the additive amount and method of OMT on the thermal stability and mechanical property of the material were investigated by TG,DSC,tensile test,flexural test,and hardness test.When 0.6%(mass fraction)OMT was added,the OMT/DFA/UPR hybrid material showed the optimum property,the initial thermal decomposition temperature,elongation at break,elasticity modulus,and flexural strength increased by 11.3%,30.6%,88.7%,and 26.9%,respectively,compared to DFA/UPR.However,in addition to the elongation at break of OMT/DFA/UPR composites increased by 22.8%,the remaining properties improved little or even decreased.