氰酸酯树脂／聚甲基丙烯酸甲酯合金的异步合成及表征

摘要

Through grafting pre-polymerized poly (methyl methacrylate) (PMMA) to bisphenol-A dicyanate resin (BADCy), BADCy/PMMA alloy materials were prepared by asynchronous synthesis method. The effects of PMMA content on the flexural strength,flexural modulus,impact strength and glass transition temperature (Tg) of the alloy materials were studied through mechanical properties tests and dynamic thermal mechanical analysis. The structure and morphology of the alloy materials were analyzed and characterized by FTIR and SEM. The results show that PMMA is grafted to the molecular chains of BADCy and they form a SIPNs. With PMMA content increasing,the flexural strength,flexural modulus,impact strength of the alloy materials increase firstly and decrease lastly in general. When the mass fraction of PMMA is 15%,the flexural strength and flexural modulus reach the maximal value which is 196.29 MPa and 9.83 GPa respectively and increases by 74.5%and 92.0%comparing with pure BADCy. When the mass fraction of PMMA is 20%,the impact strength reaches the maximal value which is 17.95 kJ/m2 and increases by 88.3%comparing with pure BACDy,the fracture surface of the alloy materials shows the feature of typical ductile fracture. Comparing with pure BADCy,Tg of the alloy materials reduced slightly.%采用异步合成法，将经过预聚的聚甲基丙烯酸甲酯(PMMA)接枝到双酚A型氰酸酯树脂(BADCy)中制备BADCy/PMMA合金材料。对合金材料进行力学性能测试和动态热机械分析，研究了不同PMMA含量对合金材料弯曲、冲击性能及玻璃化转变温度(Tg)的影响。利用傅立叶变换红外光谱和扫描电子显微镜对其结构和形态进行了分析与表征。结果表明，PMMA接枝到了BADCy的分子链上，形成了半互穿网络结构；随PMMA含量的增加，合金材料的弯曲强度、弯曲弹性模量和冲击强度总体上呈先上升后降低的趋势，当PMMA质量分数为15%时，弯曲强度和弯曲弹性模量分别达到最大，其值为196.29 MPa和9.83 GPa，比纯BADCy提高了74.5%和92.0%；当PMMA质量分数为20%时，冲击强度达到最大值17.95 kJ/m2，比纯BADCy提高了88.3%，此时材料冲击断面呈现出典型的韧性断裂特征。与纯BACDy相比，合金材料的Tg略有降低。