胶原／异丙醇共混溶液的稳态流变及其触变行为  

Steady flow and thixotropic behaviors of collagen/2-propanol blends

作　　者：李季衡[1,2] 段炼[1,2] 李国英[1,2] 

机构地区：[1]四川大学制革清洁技术国家工程实验室,四川成都610065 [2]四川大学皮革化学与工程教育部重点实验室,四川成都610065

出　　处：《功能材料》2012年第20期2876-2880,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(21076129)

摘　　要：采用流变仪考察了异丙醇对胶原溶液稳态剪切、屈服应力和触变性质的影响。实验表明,在低剪切速率下,异丙醇的浓度对体系的粘度影响较大,在高剪切速率下各体系粘度则对异丙醇浓度不敏感。幂律方程和Carreau方程能很好地拟合胶原/异丙醇共混溶液的流动曲线,通过粘度系数K、非牛顿指数n和零剪切粘度η0等准确地描述共混溶液的流变性质。通过屈服应力测试发现,异丙醇的加入降低了体系的屈服应力,改善了胶原的流动性质,但同时也使体系不稳定程度增加。另外含有1mol/L异丙醇的共混溶液触变面积小于纯胶原溶液,受剪切破坏的结构能较快速恢复,而含有2和3mol/L异丙醇浓度的共混溶液触变面积大于纯胶原溶液,受剪切而破坏的结构恢复慢,溶液不稳定性增加。The effects of steady flow, yield stress and thixotropic behaviors of collagen on the concentration of 2- propanol were studied by the rheometer. The results showed 2-propanol changed the viscosity of blends with the low shear rate, while, the viscosity of blends was insusceptible to the 2-propanol with the high shear rate. The Power low model and the Carreau model were used to fit the steady flow of the blends, and the parameters obtained from models, such as viscosity coefficient K and non Newton index n, described the rheological behav iors of blends well. The values of the yield stress of blends decreased with adding 2-propanol, suggesting that 2 propanol improved the flow of the collagen solution and the stability of blends decreased. In addition, the thixo- tropic area of the blend with lmol/L 2-propanol was smaller than that of the pure collagen solution, indicating that entangled chain could reverse soon. However, the thixotropic area of the blends with 2 and 3mol/L 2 pro- panol was larger than that of the pure collagen solution, suggesting that reversion ability of the blends de- creased and it was not good for the stability of the blends.

关 键 词：胶原 异丙醇 稳态剪切 屈服应力 触变 

分 类 号：R318.08[医药卫生—生物医学工程]