高分子单链凝聚成与线团相互穿透的多链凝聚态

高分子单链凝聚态由于链内链结构单元间存在范德化吸引作用,高分子链呈打圈链构象,而多链凝聚态由于链内链单元间的吸引作用被与相互穿透的近邻链的单元间吸引作用所屏蔽,高分子链呈高斯链构象。本文简要介绍单链凝聚态试样的制备方法,单链单晶体、单链玻璃体、溶胀的单链高弹态拉伸等的实验观察,并提出从单链凝聚态到多链凝聚态的转变过程问题,即高分子线团的相互穿透过程,目前还缺少基础了解。     

高分子单链凝聚态与线团相互穿透的多链凝聚态

高分子单链凝聚态由于链内链结构单元间存在范德华吸引作用,高分子链呈打圈链构象,而多链凝聚态由于链内链单元间的吸引作用被与相互穿透的近邻链的单元间吸引作用所屏蔽,高分子链呈高斯链构象.本文简要介绍单链凝聚态试样的制备方法,单链单晶体、单链玻璃体、溶胀的单链高弹态拉伸等的实验观察,并提出从单链凝聚态到多链凝聚态的转变过程问题,即高分子线团的相互穿透过程,目前还缺少基础了解.     

高分子单链的研究进展

随着纳米科技在高分子领域的不断升温,高分子单链凝聚态的研究引起了人们的广泛重视。高分子单链以纳米尺度的微粒孤立存在,不存在分子链之间的几何缠结。本文综述了近年来国内外高分子单链的研究进展。首先介绍了高分子单链的主要制备方法如喷雾法、冷冻干燥法、微乳液聚合法、反向沉淀法以及表面扩展膜法,接着详细介绍了高分子单链的表征技术及高分子链构象的计算机模拟技术,最后介绍了高分子单链及单分子胶束在制备金属纳米粒子领域的应用,并展望了高分子单链的研究领域和方向。     

在“高聚物的结构与性能”课程中讲透高聚物的特点

通过对高分子链的柔性、聚合物独有的熵弹性、显著的粘弹性、特有的描述链段运动的WLF方程,可能实现的大尺寸取向和小尺寸解取向、银纹、单链凝聚态、折叠链片晶和伸直链晶体、分子量的多分散性、高分子溶液特性和高聚物熔体的弹性行为等的讨论,希望能突出“高聚物的结构与性能”课程中高聚物的特点。     

高分子间相互作用的特点及意义

高分子间的相互作用与小分子间的相互作用有着显著的区别，导致高分子物质在凝聚态结构和诸多性能上明显地有别于小分子物质。本文就如下七个方面：特别强的高分子间相互作用、特殊的高聚物溶解过程、马克三角形原理、特征温度、特有的单链凝聚态、凝聚缠结和超分子体系来讨论高分子间相互作用的重要性及其对高聚物的结构和性能的影响。     

分子动态模拟研究聚丙烯单链的玻璃化转变

用分子动态模拟法对单链高分子固体微粒的玻璃化转变与主链骨架键的构象态跃迁进行了模拟研究，发展了一种表征单链高分子固体微粒玻璃化转变过程的新方法．     

利用指数律了解溶液中复杂高分子单链及聚集态结构的形状特征

高分子在溶液中的单链构象和聚集态结构是高分子科学的重要内容,在研究中往往应用到许多指数经验规律. 总结了几种通常用来研究高分子溶液的指数律方法,并介绍了指数律如何应用于复杂高分子单链及聚集态结构的形状特点研究. 通过前体溶液的调控实现对薄膜凝聚态结构以及形貌的操纵是一种新思路、新方法. 因此,深刻认识高分子在前体溶液中的本征性质尤为重要. 通过指数律研究,结合电镜、光谱等方法,可深入研究高分子溶液单链、聚集尺寸及形态结构演变与各层次结构单元的运动过程及规律,为高分子材料的分子设计、功能开发及应用奠定理论基础.     

在"高聚物的结构与性能"课程中应该引入的几个新概念

在“高聚物的结构与性能”课程教学中，很有必要向学生介绍高分子科学近十几年来的发展，尤其是在高分子凝聚态基本物理问题上的研究成果以及相关的新概念、新知识，特别是我国学者的贡献。本文较为详细地讨论了近年来作者在教学中介绍的几个新概念，如：动态接触浓度、单链凝聚态、凝聚缠结等。     

溶致性液晶高分子PBT的结构表征

聚苯撑苯并二噻唑(PBT)具有典型的溶致性液晶行为,聚合后期有液晶态搅拌乳光现象。偏光显微镜观察到具有向列型织态结构,溶液粘度随浓度变化,当进入液晶区时有明显的反常突变。对高分子链和凝聚态结构进行了X射线衍射研究,测定了晶胞参数、C轴等同周期和高分子链的取向度,并表明取向的PBT凝聚态是由刚性棒状的分子呈园柱体形态二维有序堆砌而成的。     

谈谈聚合物的结晶形态问题

向读者引介了聚合物球晶的三维立体电镜照片，并介绍了高分子科学近年来的新研究成果－尺寸已达厘米量级的聚合物宏观单晶体和只由一根大分子链结晶而成的高分子单链单晶的特殊形态。     

Effect and Mechanism of Solvent Properties on Solution Behavior and Films Condensed State Structure for the Semi-rigid Conjugated Polymers

Solvents have an essential association with polymer solution behavior. However, few researches have been deeply done on this respect. In recent years, our research group focus on the study on effect of solvent properties on solution behavior and film condensed state structure for semi-rigid conjugated polymer up till to apply for optoelectronic device. Herein, influence of solvent properties including solubility of solvent, aromaticity, polarity and hydrogen bonds on semi-rigid polymer chain solution behavior, i.e., single chain conformation, chain shape,size and chains aggregated density were studied by means of static/dynamic laser light scattering(DLS/SLS) and exponential law etc. Effect of solvent properties on condensed state structure of the semi-rigid conjugated polymer film was studied by UV absorption spectroscopy, PL spectroscopy and electron microscopy etc. The essential reasons for the influence were discovered and the mechanism was revealed. It was found that solution behavior with different solvent properties had an essential physical relationship with chains condensed state structure of the semi-rigid conjugated polymers. More importantly, there was a quantitative structure-activity relationship between solution and film. The key to this relationship depended on the interaction between solvent molecules and the semi-rigid conjugated polymer chains. This interaction could also affect optoelectronic devices performance. This study is of great significance to effectively control the condensed state structure of the semirigid conjugated polymers in the process of dynamic evolution from solutions to films. It not only enriches the knowledge and understanding of both semi-rigid conjugated polymer solution behaviors and film condensed state physics based on polymer physics, but also is meaningful to practical application for conjugated polymer and other traditional polymer systems.     

大分子链的溶致凝聚过程

研究大分子链的凝聚从溶液考虑比较合适。溶液从稀溶液向亚浓、浓溶液的转变过程,本质上就是分子链从孤立单链状态向多链穿透、关联、缠结、凝聚的过程,称其为溶致凝聚过程。分子链溶致凝聚的类型十分丰富,包括凝聚成无定形态、结晶态和溶胶-凝胶转变等,讨论了这些过程中分子链溶致凝聚的特点。简要介绍了分子链凝聚过程涉及的基本物理问题:多体问题、复杂关联效应、平均场近似、临界指数,以及研究溶致凝聚的重要方法——标度律方法。     

Based on the Second Virial Coefficient (A2) to Study Effect of the Synergistic Action of Solvent and External Electric Field on the Solution Behavior and Film’s Condensed State Structure

Chinese Journal of Polymer Science - The solventnatures are crucial to deeply reveal solution behavior of macromolecular chains, physical essence of condensed state structures formation of the film...     

染料敏化太阳电池用聚合物电解质

综述了本研究小组近年来用于染料敏化太阳电池中聚合物电解质的研究概况.设计合成了几类性能优良的聚合物电解质,较好地改进了液体电解质染料敏化太阳电池(DSSC)的使用稳定性,研究结果具有实际应用的价值,并提出了此领域研究今后的发展方向.     

Insight into carbon nanotube effect on polymer molecular orientation: an infrared dichroism study

The effect of carbon nanotubes on polymer macromolecular orientation structure during stretching of syndiotactic polystyrene/carbon nanotube nanocomposite film was quantitatively studied for the first time by an infrared dichroism technique.     

Interrogation of single synthetic polymer chains and polysaccharides by AFM-based force spectroscopy.

This contribution reviews selected mechanical experiments on individual flexible macromolecules using single-molecule force spectroscopy (SMFS) based on atomic force microscopy. Focus is placed on the analysis of elasticity and conformational changes in single polymer chains upon variation of the external environment, as well as on conformational changes induced by the mechanical stress applied to individual macromolecular chains. Various experimental strategies regarding single-molecule manipulation and SMFS testing are discussed, as is theoretical analysis through single-chain elasticity models derived from statistical mechanics. Moreover, a complete record, reported to date, of the parameters obtained when applying the models to fit experimental results on synthetic polymers and polysaccharides is presented.