聚硅氧烷/聚己内酯/环氧树脂复合体系的制备及表面性能

通过—OH和—NCO的亲核加成反应，直接合成出端硅氧烷基聚己内酯/聚硅氧烷混合物(PCL-TE-Si/PDMS-TESi)，再与环氧树脂(EP)共混制得聚硅氧烷/聚己内酯/环氧树脂复合体系。利用扫描电镜、X光电子能谱对复合体系进行了两相相容性分析和表面元素分析，通过测试复合体系的表面接触角，利用Owens-Wendt-Kaelble模型推算出复合体系的表面张力，并研究了体系的耐水性。结果表明：复合体系在固化过程中，Si元素在一定程度上向表面迁移富集；50℃固化体系的两相相容性好于室温固化体系；室温固化体系的表面张力随PCL-TESi/PDMS-TESi含量的增加逐渐下降，且低于50℃ 固化体系的表面张力；复合体系耐水性优异，当PCL-TESi/PDMS-TESi 与EP质量比为5∶5时，常温固化体系在50℃蒸馏水中浸泡7天后质量变化率小于1%。

Preparation and surface properties of polydimethysiloxane/polycaprolactone/epoxy resin composites

Silyl-terminated polycaprolactone/ polydimethysiloxane (PCL-TESi/PDMS-TESi) was directly synthesized via —OH and —NCO nucleophilic addition reaction. A series of resin composites were prepared by blending epoxy and PCL-TESi/PDMS-TESi. The morphologies and the surface elements of the composite system were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. The surface tension of the composite system was obtained based on the contact angle by Owens-Wendt-Kaelble model. The water-resistance properties of the composites were also studied. The results show that the morphologies，surface tension and water resistance properties of the composites are quite dependent on the content of PCL-TESi/PDMS-TESi and the curing temperature. The surface tension decreases with increasing PCL-TESi/PDMS-TESi content because of the Si element migrating toward the surface to some extent. The compatibility of the two phases at 50℃ curing systems is better than that at room temperature curing systems，which results in that the composites cured at 50℃have higher surface tensions than those cured at room temperature. When the mass ratio of PCL-TESi/PDMS-ESi to the epoxy is 5∶5，the mass change of composite cured at room temperature is below 1% af ter soak in distilled water at 50℃ for 7 days.