中文摘要：

考虑半柔性管状聚合物的结构特征和构成材料的各向异性特性，建立了描述其统计热力学行为的微结构化蠕虫链模型，给出了半柔性管状聚合物拉伸特性与排斥体积的解析解．分析了微管这一典型管状聚合物的统计力学性质．结果表明，在1~20μm这一细胞生物学最重要的长度区间内，微管的抗拉刚度七和平均排斥体积V与其几何长度三之间的尺度关系分别为k-L^-1.3和V-L2.5，明显区别于经典聚合物的k-L^-4和V-L^4．微管这些独特的力学性质在其捕获与定位细胞器时发挥着重要作用．

英文摘要：

Abstract： A microstructure-based wormlike chain （WLC） model was proposed for semiflexible tubular polymers taking into account their hollow tube microstructure with locally orthotropic elastic properties. Closed-form analytical solutions were obtained for the stretching behaviors and undulation space of such polymers. The results show that, in its physiologically important range of contour length L from I to 20 μm, microtubule, a typical semiflexible tubular polymer, exhibits a stretching stiffness k that scales with L as k~L^-1.3, compared with the classical WLC behavior of k~L^-4, and that the average search space of a micro- tubule scales as V-L^2.5, compared with the classical WLC behavior of V-L^4. It was speculated that the unique properties of microtubules may have profound implications for their biological functions such as search and positioning of organelles.