环氧树脂多孔复合材料的制备及性能

Preparation and Property of Porous Epoxy Composites

以环氧树脂为基体、蓖麻油酸(RA)或二聚蓖麻油酸(DRA)改性的四乙烯五胺(TEPA)(RATEPA/DRATEPA)作为固化剂、水为致孔剂、釉粉为无机填料,通过树脂-水-填料悬浮乳液复合体系聚合法,在室温下合成了环氧树脂多孔材料,采用SEM、压汞仪、电子万能试验机、TGA对多孔材料的形貌、孔径分布、孔隙率、机械性能及热性能进行了表征和测试。结果表明:随着水相质量分数和填料粒径的增大,多孔材料的孔径和孔隙率增大,压缩强度减小;随着固化剂分子量的增大,多孔材料的孔径和孔隙率减小,压缩强度增大。当填料粒径为40μm,固化剂为RATEPA,m(水相)∶m(树脂相)=2∶1时,多孔材料的综合性能最佳,其最可几孔径为3.449μm,孔隙率为21.8%,压缩强度为26.89 MPa。TGA和DTG测试结果表明:环氧树脂多孔材料的热稳定良好,具有耐高温性能,可以在高温条件下应用。

The curing agents （ RATEPA and DRATEPA） were first prepared from ricinoleic acid （RA） or dimerization ricinoleic acid （DRA） with tetraethylenepentamine （TEPA）. Then, the porous epoxy composites were prepared using epoxy resin, curing agent, glaze powder, and water via epoxy-water-filler suspended emulsion polymerization at ambient temperature. Finally, their pore size distribution, pore structure, porosity, mechanical properties and thermal properties were characterized and tested by SEM, mercury intrusion method, material testing machine and TGA. The results revealed that when the mass ratio of water to epoxy resin and particle size of glaze powder increased, the pore size and porosity of the resulting porous composites increased. The compressive strength displayed the contrary variation trend. However, the pore size and porosity decreased and the compressive strength increased with increasing of the molecular weight of curing agent. When the particle size of glaze powder was 40 p,m, the curing agent was RATEPA, and the mass ratio of water to epoxy resin was 2：1, the porous epoxy composites achieved an excellent overall performance. The pore size was 3.449 p,m, the porosity was 21.8% , and the compressive strength was 26.89 MPa. In addition, the results of TGA and DTG indicated that the obtained porous epoxy composites possessed good resistance to high temperatures and showed excellent thermal properties below 379 ℃.