摘要
基于键长涨落格子模型和动态蒙特卡罗模拟方法,引入疏水相互作用,对均聚高分子链坍塌转变动力学过程进行了模拟研究.模拟发现,其坍塌时间呈高斯分布,而平均坍塌时间随淬火深度的变化类似于蛋白质折叠,但难以发现局部最小;另外,平均坍塌时间随链长呈指数形式变化.在其坍塌动力学过程中,高分子链构象先由橄榄球状演变为项链状,进而演变为香肠状,最后形成近球状的熔融球;基于团簇数目、团簇大小和非球面参数等参量,对前人提出的动力学过程四阶段划分进行了更为清晰的界定.
Based on the bond-fluctuation lattice model and dynamic Monte Carlo simulation, with explicitly including the hydrophobie interaction between water molecular and polymer, the kinetic process for the coil-globule transition of a homopolymer chain was studied. The distribution of collapse time observed the Gaussian profile, and the variation of averaged collapse time on the quench depth was similar with that for protein folding, but exhibited no local minima. What＇ s more, the averaged collapse time was exponentially dependent on the ehainlength. In the kinetic process, the polymer chain＇ s conformation was found to evolve from an ellipsold-like random coil to necklacelike conformation, then to sausage-like conformation, and eventually to a spherical globule. The four-stage kinetic process previously proposed by other peoples has been distinctly defined in this paper via some characteristic parameters, i. e. , the number of cluster, cluster size and aspherity, thus providing a convenient criterion for stage partition and comparison for specific collapse process.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2009年第12期1238-1244,共7页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号20804023)
广东省教育厅广东高校优秀青年创新人才培育项目(基金号LYM08086)
聚合物分子工程教育部重点实验室(复旦大学)开放研究课题基金
深圳大学青年科学基金(基金号200820)资助项目
关键词
坍塌转变
动力学过程
格子链
键长涨落模型
动态蒙特卡罗模拟
Coil-globule transition, Kinetic process, Lattice chain, Bond-fluctuation model, Dynamic Monte Carlo simulation
