蚕丝蛋白与硅溶胶复合材料的研究

采用动态力学测试手段(DMA)并结合扫描电镜和拉曼光谱等方法,考察了用桑蚕丝蛋白与二氧化硅水分散体系(硅溶胶)制备的复合材料的结构与性质.结果表明,在此共混体系中,直径约为100 nm的二氧化硅聚集体与丝蛋白连续相的界面相容性良好.动态力学测试发现,复合材料的动态力学性能在15℃到55℃范围相对于纯丝蛋白材料得到了改善,二氧化硅组分的加入对丝蛋白分子链段的运动性有所阻碍,从而导致了40℃模量损耗的消失.

COMPOSITE MATERIAL MADE OF REGENERATED SILK FIBROIN AND SILICA SOL CHENG Cheng, SHAO Zhengzhong, CHEN Xin

Regenerated silk fibroin solution and silica sol were mixed to produce the silk fibroin/silica composite materials.In order to probe if there is interaction between silk protein and silica,and further more,whether the interaction can improve the mechanical properties of composite materials,the structure and properties of the silk fibroin/silica composite material were studied by dynamic mechanical analysis(DMA) together with scanning electron microscopy(SEM) and Raman spectroscopy.The SEM results revealed the good compatibility between silk fibroin and silica in the composite.Nano-sized silica particles dispersed evenly in the continuous matrices of silk fibroin.Raman spectra of the composite materials indicated that the silk fibroin was dominated by β-sheet conformation.Comparing to the pure silk fibroin material,the composites showed better dynamic mechanical properties in the range of 15℃ to 55℃.When the content of silica reached 10%,the composite material appeared absolutely no dissipation in the temperature range around 40℃.Due to both the hydrogen bond and electrostatic interaction between SiO_2 and silk fibroin,the silica particles' interfusion among the chains of protein had a motive-impeding influence on the protein chains.This influence together with the stable β-sheet conformation of silk fibroin matrices led the avoidance of modulus dissipation of the material.