高分子合金膜的聚合物间相容性预测及表征

聚合物材料合金化是改善膜性能，拓宽膜材料使用范围的一种有效手段。聚合物间的相容性是影响高分子合金分离膜结构与性能的重要因素。本文介绍了预测聚合物相容性的方法——聚合物溶度参数原则和混合焓变原则；表征高分子合金膜内聚合物间相容性的几种方法——共同溶剂法、粘度法、显微镜法、热分析及动态力学分析法、光散射法、中子散射法、红外光谱法及聚合物相互作用参数法等。     

影响高分子合金膜内聚合物间相容性的主要因素

聚合物材料合金化是改善膜性能，拓宽膜材料使用范围的一种有效手段。聚合物间的相容性是影响合金分离膜结构与性能的重要因素。文中以二元合金体系为例，探讨了影响聚合物合金膜中聚合物间相容性的各种因素。     

聚砜/环氧树脂相容性对合金膜结构和性能的影响

本文通过混合焓法预测并用相差显微镜表征了聚砜 /环氧树脂 (PSF/ER)合金体系的相容性 ,表明二者为部分相容体系。合金膜中聚合物的组成影响PSF/ER间的相容性 ,进而影响合金膜的结构和性能。随合金体系相容性下降 ,膜的平均孔径显著增加 ,水通量增大而相应的截留率下降 ;研究表明 ,改变PSF/ER间的相容性是调节膜结构、提高膜性能的有效方法     

Processing Science for the Realization of High Performance of Engineering Plastics──Introduction of Significant Items of the Eighth Five-year-plan

工程塑料高性能化的制备科学──八五重点项目介绍国家自然科学基金委员会将“工程塑料高性能化的制备科学”立为八五重点基金项目.要求利用优值概念,最大限度地发挥高聚物合金的特性,将高分子材料的制备科学与材料微观结构及宏观性能,甚至使用性能结合起来研究,探讨相容性的本质、增容作用与增容机理;在总结相分离动力学与热力学规律及其临界条件的同时归纳脆韧转变准则,发展微相分离理论;根据多相多组分体系相互作用的规律,寻....     

热敏型高分子合金材料的浊度随相态转变的群子统计参数研究

用群子统计理论研究了热敏型高分子合金体系的浊度随相态转变的过程,建立了二元高分子合金体系的线性群子统计模型,推导出该体系的相分离方程,并得到一系列热敏型高分子合金相转变群子统计参数,并进一步在理论上解释了不同剪切速率下相态转移群子参数的变化规律:相态转变群子参数r1.r2随着剪切速率的增大而减小,即相容性得到改善。并提出了8种不同类型高分子合金相图,在群子统计理论的基础上成功地模拟了实际曲线,得到了相当吻合的理论模拟曲线。     

生物高分子材料血液相容性研究

生物高分子材料广泛应用于临床医疗,可用作人工血管、起搏器、组织工程支架等,因而必须具备良好的血液相容性.综述了生物高分子材料血液相容性的研究现状,主要包括凝血、血栓形成机理以及抗凝血系统等,重点介绍了高分子材料植入体内引起凝血及血栓形成的具体机制,阐述了设计微相分离结构、化合物接枝改性、引入生物活性分子、材料表面内皮化等改善材料血液相容性的主要途径.最后从分子生物学角度出发展望了今后高分子材料改性的研究方向.     

基于相分离制备高分子微孔材料的新探索

对制备聚合物微孔膜的相分离法进行了评述.简介了课题组几种基于相分离制备聚合物微孔材料的新探索,包括热致相分离,冷冻诱导相分离,聚合致相分离,基板诱导共混聚合物的有规相分离.     

热致相分离法制备聚合物微孔膜的研究进展

分别从S-L相分离和L-L相分离两方面简述了热致相分离法制备聚合物微孔膜的成膜过程.从聚合物分子量、聚合物浓度、稀释剂与聚合物的相互作用、稀释剂的流动性及结晶、冷却速度及冷却方式、萃取剂的种类及萃取剂的抽提方式、成核剂几方面总结TIPS法制膜的研究进展,并从膜材料、膜结构以及制膜方法三方面阐述热致相分离法制膜的发展趋势.     

医用高分子复合材料

高分子复合材料的开发、利用是改善生物材料生物相容性的一条有效途径。本文首先介绍了通过高分子材料与无机物、金属、非金属碳及高分子本身复合来提高材料生物相容性研究的进展。然后,着重讨论了高分子复合材料的微相分离结构与抗凝血性能的关系。最后,概述了高分子材料和生体成分、组织的复合作用。     

高聚物共混增容技术的研究进展

综述了高分子合金相容性研究的现状与发展，介绍了各种增容方法及其应用，通过改善共混物的相容性来提高高分子合金的力学性能是制备新型高分子材料的一种新途径。     

热致相分离法制备高聚物微孔结构材料的研究进展

热致相分离法是一种制备微孔结构材料的新方法,采用该方法可以将常温下缺少合适溶剂的高聚物制成多孔材料。为促进该方法广泛而深入的应用,文中归纳了可采用热致相分离法制备微孔膜或细胞支架的结晶性和无定型高聚物,及其所对应的稀释剂体系。综述了稀释剂种类、工艺参数(高聚物浓度、冷却条件)和添加剂等因素对热力学相图、相分离机理、微孔结构及材料性能的影响。     

聚合物在生物传感器中的应用研究进展

综述了近年来高分子材料在生物传感器的应用研究进展，介绍了高分子复合物，水凝胶，溶胶－凝胶，改性聚合物，电生聚合物，氧化还原聚合物，离子交换聚合物和具有特殊结构的聚合物在酶和电子媒介体固定化方面的应用以及由其制备的生物传感器的性能，对应用于生物传感器的高分子材料的分类，制备方法和原理及其特性进行了深入的探讨，并指出了目前其存在的主要问题及解决方法，对高分子材料在生物传感器中的应用前景予以展望。     

Phase separation micromolding: a new generic approach for microstructuring various materials

Phase separation micromolding (PSmicroM) is a versatile microfabrication technique that can be used to structure a very broad range of polymers, including block copolymers and biodegradable and conductive polymers without the need for clean-room facilities. By incorporating a subsequent process step, carbon, ceramic, and metallic microstructures can also be fabricated from a polymeric or hybrid precursor. The replication process is straightforward and cost-effective. It relies on phase separation of a polymer solution while in contact with a structured mold. Intrinsic shrinkage during the phase separation facilitates the release of the replica from the mold, which increases the reliability of the process even at small feature sizes, thin polymer films, or high aspect ratios. Under suitable circumstances perforation of the polymer film can be obtained, resulting in completely open "through" microstructures. Furthermore, porosity can be introduced in a microstructure, which may result in unknown functionalities.     

导热高分子材料的研究与应用

介绍了金属材料、非金属材料、高分子材料的导热机理,以及导热填料搀杂高分子材料的导热理论模型。综述了各种高导热填料的研究进展和它们在导热高分子材料中的应用情况。最后提出了导热高分子材料的研究方向。     

Application of fractal fracture mechanics to polymers and polymeric composites

It is shown that the fundamental concepts of fractal fracture mechanics can be applied both to polymers and polymeric composites and to metals and ceramics. The critical crack opening displacement can be chosen as a scale of fracture of polymeric materials. The results obtained for polymers and polymeric composites are described by the same sigmoidal dependence, which means that the regularities of fracture processes in these materials are common.Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 40, No. 4, pp. 53–57, July–August, 2004.     

Electronic spectra of the crystalline polymers of C60: photoluminescence study at high pressure

Specific details of the electronic spectra of perfect crystalline polymers of C60 were studied by means of the photoluminescence spectra measurements at normal conditions and at high pressure up to 4 GPa. The structure of the photoluminescence spectra, the intensity distribution between the principal bands and the pressure-induced shift of the bands differ considerably among the pristine C60, linear orthorhombic and planar tetragonal and rhombohedral polymeric phases of C60. Unlike the planar polymers of C60, the linear orthorhombic polymer exhibits irreversible changes in the photoluminescence spectrum under simultaneous application of high pressure and laser irradiation. The changes observed in the photoluminescence spectra of the planar polymeric phases of C60, as compared to the pristine material, are discussed in relation to the corresponding changes in the calculated electronic structure of the pristine C60 and its polymeric phases. The observed photoluminescence spectral structure along with the pressure behavior of the photoluminescence spectra are very sensitive to the structure of the polymers as well as to the C60 cage deformations and can be used to effectively characterize the various polymeric phases of C60.     

High-Performance Polymeric Materials through Hydrogen-Bond Cross-Linking

It has always been critical to develop high-performance polymeric materials with exceptional mechanical strength and toughness, thermal stability, and even healable properties for meeting performance requirements in industry. Conventional chemical cross-linking leads to enhanced mechanical strength and thermostability at the expense of extensibility due to mutually exclusive mechanisms. Such major challenges have recently been addressed by using noncovalent cross-linking of reversible multiple hydrogen-bonds (H-bonds) that widely exist in biological materials, such as silk and muscle. Recent decades have witnessed the development of many tailor-made high-performance H-bond cross-linked polymeric materials. Here, recent advances in H-bond cross-linking strategies are reviewed for creating high-performance polymeric materials. H-bond cross-linking of polymers can be realized via i) self-association of interchain multiple H-bonding interactions or specific H-bond cross-linking motifs, such as 2-ureido-4-pyrimidone units with self-complementary quadruple H-bonds and ii) addition of external cross-linkers, including small molecules, nanoparticles, and polymer aggregates. The resultant cross-linked polymers normally exhibit tunable high strength, large extensibility, improved thermostability, and healable capability. Such performance portfolios enable these advanced polymers to find many significant cutting-edge applications. Major challenges facing existing H-bond cross-linking strategies are discussed, and some promising approaches for designing H-bond cross-linked polymeric materials in the future are also proposed.     

Membrane Engineering: Phase Separation in Polymeric Giant Vesicles

Cell membranes exhibit elaborate lipidic patterning to carry out a myriad of functions such as signaling and trafficking. Domain formation in giant unilamellar vesicles (GUVs) is thus of interest for understanding fundamental biological processes and to provide new prospects for biocompatible soft materials. Lipid rearrangements in lipidic GUVs and lipid/polymer GUVs are extensively studied whereas polymer/polymer hybrid GUVs remain evasive. Here, the focus is on the thermodynamically driven phase separation of amphiphilic polymers in GUVs. It is demonstrated that polymer phase separation is entropically dictated by hydrophobic block incompatibilities and that films topology can help to determine the outcome of polymeric phase separation in GUVs. Lastly, Janus‐GUVs are obtained and GUVs exhibit a single large domain by using a compatibilizing hydrophobic block copolymer.     

Screening of anionic-modified polymers in terms of stability,disintegration, and swelling behavior

This study aimed to screen the stability, disintegration, and swelling behavior of chemically modified anionic polymers. Investigated polymers were well-known and widely used staples of the pharmaceutical and medical field, namely, alginate (AL), carboxymethyl cellulose (CMC), polycarbophil (PC), and hyaluronic acid (HA). On the basis of amide bond formation between the carboxylic acid moieties of anionic polymers and the primary amino group of the modification ligand cysteine (CYS), the modified polymers were obtained. Unmodified polymers served as controls throughout all studies. With the Ellman’s assay, modification degrees were determined of synthesized polymeric excipients. Stability assay in terms of erosion study at physiological conditions were performed. Moreover, water uptake of compressed polymeric discs were evaluated and further disintegration studies according to the USP were carried out to define the potential ranking. Results ranking figured out PCCYS?>?CMCCYS?>?HACYS?>?ALCYS in terms of water uptake capacity compared to respective controls. Cell viability assays on Caco-2 cell line as well as on RPMI 2650 (ATTC CCL30) proved modification not being harmful to those. Due to the results of this study, an intense screening of prominent anionic polymer derivate was performed in order to help the pharmaceutical research for the best choice of polymeric excipients for developments of controlled drug release systems.     

Similar Behavior Between Polyfullerenes and Charged Polymers. Extreme Polyelectrolyte Effects in Gel Permeation Chromatography Studies

Fullerene polymers with high fullerene contents were studied by use of gel permeation chromatography (GPC). Surprisingly, the polymer samples exhibit the chromatographic behavior that is characteristic of charged polymers. The extreme poly electrolyte effects observed for the fullerene polymers are rationalized in terms of localized charges in the polymer structures due to large polarizibilities of the polymeric fullerenes.