The General Aspects of Diffusion of Water in Polymers

Abstract

The general affects of diffusion of water in polymers are reviewed and discussed.     

高吸水性树脂的吸水机理及制备方法

高吸水性树脂是一种新型的功能高分子材料,由于它能吸收自身质量几百至上千倍的水,且吸水膨胀后生成的凝胶具有优良的保水性。因而在生理卫生用品、土木建筑、食品、农业、医药等方面具有广阔的应用前景。本文介绍了高吸水性树脂的研究状况,吸水机理以及制备方法,并对高吸水性树脂的发展前景作了展望。     

The Mechanism of Radiation Destruction of Dyes in Polymers: A New Method for Increasing the Stability of Dyed Polymers Based on Oscillative Cross-Relaxation

Abstract

Discussion of the mechanism of radiation destruction of dyes in polymers, which is associated with solid-phase chemical reaction between dye molecules and oxyradicals appearing either on destruction of polymer molecules or on oxidation of macroradicals by the oxygen dissolved in the matrix. Experimental results are given on radiolysis and photolysis of polymethyl methacrylate with a “resonant” low molecular weight additive and dye (nickel dithiobenzil complex and vanadyl phthalocyanine), which demonstrate the decisive role of oscillative cross-relaxation between macromolecules and molecules of the additive in increasing the radiation stability of dyed polymers.     

全生物降解高分子材料的发展现状

生物降解高分子材料因医药、医学、环境等方面的需求而迅速发展起来,在近几十年,世界先进国家非常重视该领域的研究和开发工作,并取得一些重要进展。在简要介绍生物降解高分子材料的降解过程后,着重对全生物降解高分子材料的发展现状作了综述,其中包括化学合成高分子和天然高分子的研究和开发,同时对生物降解高分子材料存在的问题及其将来发展趋势等方面进行了讨论。     

疏松砂岩气藏水锁机理模拟

水锁损害是气藏开采中最常见的损害之一。对于以层内水、层间水和边水为主的疏松砂岩有水气藏,出水水源不同,气井表现出了不同的产水特征和不同的水锁损害程度。目前,大多数学者对气田水锁研究集中在微观模拟实验定性的研究阶段,具体水锁损害对现场开发指标的影响,还缺乏定量化的研究手段。本文以青海xx气田为例,用1数模模拟方法研究了不同产量和生产压差等开采指标情况下,疏松砂岩层内水和边水对气藏的影响程度,定量分析了这两种水源对气田水锁损害的程度,为今后气田配产和合理生产压差制定及防水、治水,提供了定性和定量化的依据。     

导电聚合物的合成和应用前景

本文对导电聚合物的性能，一般的合成方法如链聚合法和分步骤合法，特殊的合成方法如电化学合成和光化学聚合作了较详细的评述。介绍了氧化或还原试剂掺合进这些聚合物中，被称为掺杂剂的类型和掺杂方法。最后介绍了这些新材料的某些应用领域以及存在的问题。     

配位聚合物的研究进展

综述了近年来比较热门的研究领域——配位聚合物,它是由过渡金属和有机配体自组装而形成的,具有独特的空间几何构型,在非线性光学材料、磁性材料、超导材料,微孔材料及非对称催化等诸多方面都有广阔的应用前景。本文就不同配体的配位聚合物进行了分类研究。     

Investigation of nanostructures and properties of sulfonated poly(arylenethioethersulfone) copolymer as proton conducting materials by small angle neutron scattering

Sulfonated poly(arylenethioethersulfone) copolymer (SPTES-50), a promising candidate material for proton exchange membrane fuel cell (PEMFC), exhibited excellent thermal stability, high proton conductivity (135 mS/cm at 85 °C, 85% relative humidity), and electrochemical property. Small angle neutron scattering (SANS) of fully hydrated SPTES-50 membranes revealed the presence of embedded spherical nanodomains containing ionic group and water within the polymer membranes. The polydispersity of the nanoscale structure limited scattering contrast between the polymer backbone and sulfonated groups, and precluded analysis of intermediate and large scattering vectors in terms of the polymer-water interface structure. Inter-cluster correlations associated with the large extent of water absorption in the fully hydrated SPTES-50 membranes were accounted by Percus-Yevick liquid-like ordering of polydispersed hard sphere model with Schulz polydispersity approximation. Approximation of their low q upturn with an exponential decay results in a decay of −3 at 25 °C accounted for inter-cluster correlations which changed to a decay of −1.1 at 55 °C and 77 °C. This indicated a change in morphology upon increase of temperature such as to fractal morphology or an interconnected cylindrical network. The scattering patterns don't exhibit any further changes within examined range of q when the temperature increased from 55 °C to 77 °C. The number density of ionic clusters remained approximately constant (∼1.1818 × 10¹⁷ cm³), which indicated that additional water adsorbed by the polymer at the elevated temperature did not result in substantial coalescence of the clusters. Transmission electron microscopy (TEM) observation of the silver exchanged SPTES-50 membranes exhibited aggregates of Ag⁺ embedded within the dry membranes which can be approximated by isolated spheres.     

Recent Advances in Organotin Polymers

The science and technology of organotin polymers are based on the properties of organotin compounds which have surprisingly diverse applications, including use as stabilizers for vinyl chloride and other olefm polymers, as industrial catalysts, as industrial and agricultural biocides, and as antifouling and wood-preserving agents. In keeping with the expanding use of organotin compounds, the worldwide production of organotin compounds has risen dramatically from less than 50 tons/yr in 1950 to over 25,000 tonslyr in 1975 [1]. The chemis-try of organotin compounds, including the preparative methods, properties, chemical reactions, and uses, has been reviewed in several recent monographs and symposia proceedings [1–5]     

自膨润型树脂留香剂的制备及应用

以丙烯酸和丙烯酸酯类进行共聚，然后用环氧氯丙烷同时进行共聚分子间及共聚分子与纤维素之间的两种交联，在纤维素上形成单分子层交联丙烯酸酯的网络结构。这种结构对油性香精具有非常好的留香作用，最长保香期为９６天，耐洗４８次。     

Direct Mass Spectrometry of Polymers

The analysis of polymers by direct mass spectrometry is reviewed, and the principles of the method and some experimental aspects are discussed. Both pyrolysis and desorption methods are described. The mass spectrometric method provides the characterisation of intractable materials and their detection at the submicrogram level; the simultaneous identification and detection of additives or oligomers contained in polymer samples; the identification of components of polymer mixtures, the sequential analysis of copolymers; the identification of the primary thermal fragmentation products of polymers. Direct mass spectrometry has been widely applied to the structural analysis of synthetic and natural polymers. Published work covers nearly all classes of polymers.     

Polymers for enhanced oil recovery: A paradigm for structure–property relationship in aqueous solution

Recent developments in the field of water-soluble polymers aimed at enhancing the aqueous solution viscosity are reviewed. Classic and novel associating water-soluble polymers for enhanced oil recovery (EOR) applications are discussed along with their limitations. Particular emphasis is placed on the structure–property correlations and the synthetic methods. The observed rheological properties are conceptually linked to the polymer chemical structure (1) and topology (2). In addition, the influence of external parameters, e.g. temperature, pH, salt, and surfactant, on the rheological behavior is reviewed. Progress booked in deeper understanding of the structure–property relationship is thoroughly discussed. Furthermore, a critical overview of the synthetic methods as well as of the solution properties of these polymers is provided. In this respect the influence of “internal” (i.e. chemical structure) and “external” (vide supra) factors on these properties provide a conceptual toolbox for the rationalization of the response of water-soluble polymers to external stimuli. In turn, such rationalization constitutes the basis for the design of new polymeric structures for EOR applications.     

国内外降解塑料发展动向

塑料为人类带来了方便,但同时也带来了日益严竣的环境问题。因此,降解塑料已引起了人们的极大兴趣,希望借此找到一个解决废弃塑料的最好方法。本文综述了降解塑料的分类以及国内外研究发屐情况及趋势。     

反应性高聚物对聚合物共混体系的增容作用

简要介绍了聚合物共混相容性的基本原理,讨论了增容反应的特点与类型,着重论述了反应性高聚物的制备技术、研究现状及其对聚合物共混体系的增容作用效果。     

季戊四醇-偏苯三酸酐-环氧氯丙烷合成超支化聚合物

以季戊四醇为“中心核”，与1，2，4-偏苯三甲酸酐和环氧氯丙烷反应合成超支化碱溶性聚酯，利用合成聚合物分子外围的羧基与甲基丙烯酸缩水甘油酯反应，在超支化聚合物分子外围引入反应性甲基丙烯酰氧基．研究了树脂组成对感光性和碱溶性的影响．结果表明：通过调整分子外围的羧基及反应性甲基丙烯酰氧基含量，可以获得较好的碱溶性和光固化性能。     

On the Mechanism of Laser Destruction of Polymers: Effect of Low-molecular Weight Additives Stemming from Oscillatory Cross Relaxation

Abstract

The vibrational cross-relaxation mechanism of polymer destruction suppression under laser irradiation are discussed. The experimental data are presented showing the influence of low molecular weight additives on laser damage resistance of optical polymers.     

热塑性淀粉塑料吸水性研究

采用增塑剂和热剪切方法制备热塑性淀粉塑料(TPS),在一定相对湿度环境下,测定不同配方TPS试样的含水量,研究了增塑剂种类(甘油和甲酰胺)与用量、直链淀粉用量和聚乳酸用量对TPS吸水性的影响。并对含水量随时间的变化曲线与Peleg模型曲线拟合分析,证明了Peleg模型在描述热塑性淀粉吸水过程的有效性和可靠性。     

新型缔合聚合物ADH溶液性能研究

研究了疏水缔合水溶性聚合物稀溶液的盐增粘性、抗温性、pH值效应,分析了溶液中聚合物与外加表面活性剂的相互作用,并初步研究了剪切速率对聚合物溶液粘度的影响。     

The Maximum Peel Strength of Pressure-Sensitive Styrene-Butadiene Emulsion Polymers

Peel strengths of five pressure-sensitive styrene-butadiene emulsion polymers, having different amounts of gel and different glass transition temperatures, have been determined as a function of temperature and peel rate. For each peel rate, the peel strength reaches a maximum at a particular temperature, and this maximum peel strength is associated with the change of the mode of failure from cohesive to adhesive. The maximum peel strength is found to be largely independent of the gel level and possibly of the glass transition temperature of the polymer within the domain of pressure-sensitive polymeric properties. The maximum peel strength appears to be dependent on the kind of substrates and the stabilization system of the emulsion polymers (surface free energy properties of the bonded interfaces).     

水溶性高分子化合物对乳化蜡稳定性影响的研究

以水溶性高分子物质作为添加剂,与不同配方的阴离子型、阳离子型,非离子型乳化剂进行复配,考察高分子物质作为添加剂对乳化蜡性状及稳定性影响。结果表明：添加水溶性高分子后,非月E型复配乳化剂制备的乳液粘度变大,稳定性增强;随着高分子化合物疏水性增强,阴离子型乳化剂制备的乳化蜡越稳定;高分子化合物与阳离子型乳化剂的电性差异越大则相互作用越强。