丙烯酸铈（Ⅲ）－丙烯酸乙酯对明胶的聚合鞣制作用

研究了丙烯酸铈（Ⅲ）配合物的合成及其与明胶的配位反应。以（ＮＨ４）２Ｓ２Ｏ８－ＮａＨＳＯ３作引发剂，用丙烯酸乙酯（ＥＡ）对明胶进行聚合鞣制改性。考察了温度、时间、引发剂和单体浓度及铈离子含量等因素对聚合鞣制过程的影响，并讨论了反应机理。     

种子乳液聚合法制备多孔乳胶粒

用批量乳液聚合法制备了苯乙烯（Ｓｔ）———甲基丙烯酸甲酯（ＭＭＡ）二元共聚种子乳液Ｓ１以及Ｓｔ ＭＭＡ 丙烯酸（ＡＡ）三元共聚种子乳液Ｓ２,通过连续法无皂种子乳液聚合合成了一系列不同ＡＡ或ＭＡＡ（甲基丙烯酸）含量的Ｓｔ、ＭＭＡ三元共聚乳液．将所得复合胶乳进行碱／酸分步处理,得到具有多孔结构的乳胶粒．用透射电镜对胶粒形态进行了表征,考察了不饱和酸种类和用量、碱处理初始ｐＨ值及溶胀剂对胶粒成孔的影响．     

丙烯酸铈（Ⅲ）—丙烯酸乙酯对明胶的聚合鞣制作用

研究了丙烯酸铈（Ⅲ）配合物的合成及其与明胶的配位反应，以（ＮＨ４）２Ｓ２Ｏ８－ＮａＨＳＯ３作引发剂，用丙烯酸乙酯（ＥＡ）对明胶进行聚合鞣制改性。考察了温度、时间、引发主单体浓度及铈离子含量等因素对聚合鞣制过程的影响，并讨论了反应机理。     

含氮聚硅氧烷配位体及其与金属离子的络合作用

研究ｎ－β（氨乙基）－γ（氨丙基）三乙氧基硅烷［ＮＨ２（ＣＨ２）２ＮＨ（ＣＨ２）３Ｓｉ（ＯＥｔ）３］与二甲基二乙氧基硅烷［（ＣＨ３）２Ｓｉ（ＯＥｔ）２］共水解，制备含－（ＣＨ２）３ＮＨ（ＣＨ２）２ＮＨ２功能基的聚硅氧烷配位体。用ＩＲ、１ＨＮＭＲ和元素分析法对共聚产物的结构进行了分析，同时用紫外－可见光谱法和ＳＥＭ考察了共聚产物与Ｃｕ２＋等金属离子的络合作用。结果发现，两种单体进行了共水解反应，而且随着ＮＨ２（ＣＨ２）２ＮＨ（ＣＨ２）３Ｓｉ（ＯＥｔ）３比例增加，水解程度提高。共聚产物可以与Ｃｕ２＋离子形成稳定的络合物，但不能与Ｚｎ２＋离子或Ａｌ３＋离子形成稳定的络合物或螯合物。     

丙烯酸酯无皂乳液稳定性研究

研究了亲水性单体ＡＡ和引发剂Ｋ２Ｓ２Ｏ８用量对三元共聚物（ＭＭＡ／ＢＡ／ＡＡ）无皂乳液（ｐＨ＝８）的电解质稳定性、冻融稳定性和机械稳定性的影响。当乳液电解质稳定性最好时存在ＡＡ和Ｋ２Ｓ２Ｏ８用量最佳值,而乳液的机械稳定性则随ＡＡ和Ｋ２Ｓ２Ｏ８用量增大而迅速提高。乳液中加入丙酮可以改善其稳定性。     

氧化—还原低温引发苯乙烯／丙烯酸丁酯细乳液聚合粒度分 …

用氧化还原引发剂（ＮＨ４）２Ｓ２Ｏ８／ＮaＨＳＯ３研究了苯乙烯（Ｓt）低温下的细乳液共聚合，细乳液单体液滴在亚微米级（１００～４００ｎｍ），测定了过程中粒子大小及分布的变化，发现细乳液聚合随引发剂、乳化剂和共乳化剂浓度的增加，乳胶粒子尺寸变小，分布变宽，并且比相同条件下传统乳液聚合的粒子大。计算了聚合过程中粒子数变化规律及乳化剂覆盖率，讨论了细乳液与传统乳液中引发剂、乳化剂对反应过程的影响及成核机理     

含氢聚甲基硅氧烷／丙烯酸丁酯／羟甲基丙烯酰胺复合乳液的研究：———原？…

采用含氢聚甲基硅氧烷（ＰＨＭＳ）与丙烯酸酯类单体进行接枝共聚，制得兼具二者优异性能的新型ＰＨＭＳ／丙烯酸丁酯（ＢＡ）／羟甲基丙烯酰胺（ＮＭＡ）复合聚合物乳液。讨论了ＰＨＭＳ、ＮＭＡ和引发剂用量对该复合乳液的聚合反应转化率、稳定性及粘度的影响。采用透射电子显微镜和粒度测试仪对不同反应条件下制备的乳液的粒度进行了测定。同时对聚合反应的机理、产物的结构及胶膜性能作了考察。结果表明：通过乳液聚合，得到了Ｐ     

高选择性透过二氧化硫气体分离膜的研究 （Ⅳ）不同烃基乙烯基亚砜接枝聚乙烯醇膜的透过性能

研究了不同烃基乙烯基亚砜接枝聚乙烯醇（ＰＶＡ－ＲＶＳＯ，Ｒ＝Ｍｅ，Ｅｔ，ｔ－Ｂｕ，Ｐｈ）膜对纯ＳＯ２、Ｎ２的透过性能以及ＳＯ２／Ｎ２混合气体的分离性能．结果表明上述膜对ＳＯ２具有高的选择性．对不同烃基乙烯基亚砜接枝膜进行了比较．     

二氧化碳-氧化苯乙烯的共聚反应

由ＣＯ２－氧化苯乙烯（ＳｔＯ）配位催化共聚制得脂肪族聚碳酸苯亚乙酯,并用 ＩＲ、１ＨＮＭＲ和 ＤＳＣ等进行表征,用 ＴＧ对聚合物的热稳定性进行了分析。     

含氢聚甲基硅氧烷/丙烯酸丁酯/羟甲基丙烯酰胺复合乳液的研究——原料配比对乳液及胶膜性能的影响

采用含氢聚甲基硅氧烷（ＰＨＭＳ）与丙烯酸酯类单体进行接枝共聚，制得兼具二者优异性能的新型ＰＨＭＳ／丙烯酸丁酯（ＢＡ）／羟甲基丙烯酰胺（ＮＭＡ）复合聚合物乳液．讨论了ＰＨＭＳ、ＮＭＡ和引发剂用量对该复合乳液的聚合反应转化率、稳定性及粘度的影响．采用透射电子显微镜和粒度测试仪对不同反应条件下制备的乳液的粒度进行了测定．同时对聚合反应的机理、产物的结构及胶膜性能作了考察．结果表明：通过乳液聚合，得到了ＰＨＭＳ／ＢＡ／ＮＭＡ共聚物，控制ＰＨＭＳ、ＮＭＡ、引发剂等用量可制得粒度和粘度适中，具有较高转化率的稳定ＰＨＭＳ／ＢＡ／ＮＭＡ复合聚合物乳液，该乳液所制得的胶膜具有优良的性能     

Studies on preparation and properties of NIPAAm/hydrophobic monomer copolymeric hydrogels

A series of thermoreversible copolymeric hydrogels with various molar ratios of N-isopropylacrylamide (NIPAAm) and hydrophobic monomers such as 2,2,3,3,4,4,5,5-octafluoropentyl methacrylate (OFPMA) and n-butyl methacrylate (BMA) were prepared by emulsion polymerization. The effect of hydrophobic monomer on the swelling behavior and mechanical properties of the present copolymeric hydrogels was investigated. Results showed that the equilibrium swelling ratio and critical gel transition temperature (CGTT) decreased with an increase of the content of hydrophobic monomer, but the gel strength of the gel increased with an increase of the content of hydrophobic monomer. Due to stronger hydrophobicity of OFPMA, the NIPAAm/OFPMA copolymeric hydrogels had lower swelling ratios and higher gel strengths than NIPAAm/BMA copolymeric gels.     

A sunscreen-tanning compromise: 3D visualization of the actions of titanium dioxide particles and dihydroxyacetone on human epiderm

The self-tanning agent dihydroxyacetone (DHA) was applied to human skin samples, and its effect on light absorption was followed in time to study the DHA influence inside the different layers of skin. Application of DHA shows increased light absorption in the visible light region, as evidenced by skin tanning. The tanning effect is enhanced by UV irradiation and appears localized in the near-stratum corneum layer as revealed by depth analysis of the time signal. As a reference, application of an emulsion containing titanium dioxide particles shows clear surface stability and a screening of light penetration beyond the stratum corneum.     

甲基丙烯酸甲酯与甲基丙烯酸异丁酯或丙烯酸酯类的乳液共聚合及其共聚物热裂解的研究

<正> 彩色显像管荧光屏的临时涂膜材料目前大量使用乳液型成膜材料,文献上已报道的有甲基丙烯酸甲酯和丙烯酸酯类为主要组份的Rhoplex-B-74等,李福绵等人为了制得低灰份的成膜材料,曾采用甲基丙烯酸-β-羟基酯与甲基丙烯酸异丁酯进行乳液共聚合,但只能制得固含量为15—17％的乳液,一般说来,采用离子型乳化剂虽可制得固含     

Structure and properties of the graft copolymer of starch and p‐hydroxybenzoic acid using horseradish peroxidase

A modified starch tannage was synthesized by free radical graft copolymerization of degraded starch with p‐hydroxybenzoic acid (pHA) using horseradish peroxidase/H₂O₂ as the initiator. In this study, the effects of the degree of degradation of the starch, dosage of pHA, polymerization temperature, system pH, and horseradish peroxidase content on the tanning properties of the graft copolymer were investigated. The shrinkage temperature of leather tanned by the graft copolymer was 78 °C. The thickness increment ratio of the retanned leather was 21.6%, and meanwhile the retanned leather showed better softness. The results indicate that the graft copolymer has excellent tanning and retanning properties. The structure of the graft copolymer was analyzed by Fourier Transform Infrared Spectroscopy (FTIR), ¹Hydrogen‐Nuclear Magnetic Resonance (¹H‐NMR), and ¹³Carbon‐Nuclear Magnetic Resonance (¹³ C‐NMR) and Gel Permeation Chromatography (GPC). Compared with conventional methods, we show that a “green” leather tannage could be achieved using a radical graft copolymerization of starch and phenols. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of graft copolymer on demixing of immiscible polymers in solution

The effect of graft copolymer on the demixing of solutions of two immiscible homopolymers and critical conditions for emulsion formation were studied. The graft copolymer used in the present work consists of one backbone poly(vinyl acetate) (PVAc) and one branch polystyrene (PS). PVAc and PS of various degrees of polymerization were used as immiscible homopolymers. The common solvent was benzene. When the concentration of homopolymer blend was not sufficiently higher than the critical concentration for demixing of the blend solution, no stable emulsion was formed, even when a considerable amount of graft copolymer was present, and the added graft copolymer merely reduced the demixing rate. However, as the blend concentration was increased, a stable emulsion could readily be obtained by addition of rather small amounts of graft copolymer. The radius of emulsion droplets was inversely proportional to the weight ratio of the graft copolymer to the dispersed component polymer, in accordance with the theoretical prediction. It was concluded that the emulsions were stabilized against coagulation by graft copolymer molecules fixed strongly as a monolayer on the interface of the emulsion.     

Amphiphilic ABA triblock copolymer as surfactant in syntheses of microlatexes bearing cationic groups

Polystyrene microlatexes have been prepared by conventional emulsion polymerization with a novel amphiphilic water‐soluble ABA triblock copolymer, poly[2‐(dimethylamino)ethyl methacrylate]₁₅‐b‐poly(propylene oxide)₃₆‐b‐poly[2‐(dimethyl‐amino)ethyl methacrylate]₁₅ (PDMAEMA₁₅‐PPO₃₆‐PDMAEMA₁₅), as a polycationic emulsifier under acidic or neutral conditions. The ABA triblock copolymer was developed by oxyanion‐initiated polymerization in our laboratory. In this study, it acted well both as a polycationic polymeric surfactant to form block copolymeric micelles for emulsion polymerization and as a stabilizer to be anchored into the polystyrene microlatex or adsorbed onto its surface. The results obtained with various copolymer concentrations and different pH media showed that microlatex diameters decreased remarkably with increased concentration of this ABA triblock copolymeric emulsifier, but were not as much affected by the pH of media within the experimental range of 3.4–7.0. The observed difference of the particle sizes from transmission electron microscopy and dynamic light scattering measurements is discussed in terms of the effect of the absorbed surfactants and their electrical double layers. This difference has led to the formation of a cationic polyelectrolyte fringe on the surface of microspheres. The final microlatexes were characterized with respect to total conversion, particle diameter, and particle size distribution as well as colloidal stability. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3734–3742, 2002     

壳多糖与丙烯酸丁酯的乳液接枝共聚研究

以十二烷基苯磺酸钠为乳化剂，过硫酸钾－亚硫酸氢钠为引发剂，研究了壳多糖与丙烯酸丁醋的乳液共聚合，结果表明当［Ｋ２Ｓ２Ｏ８］＝［ＮａＨＳＯ３］＝２．５７×１０－３ｍｏｌ·１－１，［ＢＡ］＝０．６８ｍｏｌ．１－１，［Ｃｈｉｔｏｓａｎ］＝１９．２ｇ·ｌ－１，在７０℃下反应５小时，共聚反应的接技率和接枝效率均较高．用红外光谱，差热分析，Ｘ射线衍射，扫描电镜对接技共聚物进行了表征，此外测试了共聚物胶乳成膜的机械性能，表明用丙烯酸丁酯对壳多糖进行接枝改性，可提高壳多糖的韧性，扩大其应用范围．     

甲壳素和壳聚糖的接枝共聚改性

天然高分子甲壳素、壳聚糖由于分子链上大量存在的反应性官能团 ,易于通过自由基引发与乙烯基单体接枝共聚 ,也可与其它高分子链偶合制得接枝共聚物。通过接枝共聚改性 ,可以赋予甲壳素和壳聚糖以某些新的性能 ,扩大了其应用范围。本文对甲壳素、壳聚糖的接枝共聚改性反应进展、机理以及产物的性能等进行了介绍     

微波辐照下HPMC-g-PMMA的合成及表征

使用微波辐照,在水溶液中以K2S2O8／NaHSO3氧化还原引发体系引发甲基丙烯酸甲酯在羟丙基甲基纤维素上的乳液接枝聚合。讨论了微波辐照下反应时间、单体用量、引发剂浓度、pH值对接枝率的影响,并与水浴条件下的接枝共聚进行了比较。用红外光谱、热重分析、X射线衍射对接枝共聚物进行了表征。测试了其溶解性,结果表明接枝物具有良好的抗有机溶剂以及强酸、强碱的性能。     

The apparent solubility product of cerous fluoride

The apparent solubility product of cerous fluoride has been determined to be 8.1 ± 1.1·10^-16 und 1.1 ± 0.5·10^-15 by radiometric and conductometric methods respectively. Hydrolysis of cerous fluoride is thought to be negligble. The effect of hydrogen-ion concentration on the solubility of cerous fluoride has been measured in solutions of perchloric acid of varying acidity. The solubility Was found to decrease slightly as the pH decreased from 5 to 2 and then to increase rapidly as the pH further decreased from 2 to 0.