聚烯烃表面改性对润湿性影响的研究进展

表面改性能有效提高聚烯烃的表面润湿性,从而扩大聚烯烃的应用领域。本文介绍了近几年国内外通过等离子体处理、表面光接枝、辐射接枝、化学接枝、等离子体接枝等方法对聚烯烃表面润湿性改性的研究进展。并介绍了各种改性对聚烯烃润湿性的影响。     

聚合物光接枝表面改性的方法和影响因素

简要介绍了聚合物光接枝表面改性的方法，并分析了聚合物光接枝表面改性的几种方法，着重分析了基体、接枝单体、光敏剂、溶剂、接枝方法、温度和光照时间等因素对聚合物光接枝表面改性的影响。     

聚合物表面紫外光接枝技术及应用进展

聚合物表面紫外光接枝技术可用于聚合物材料的表面化学结构和物理形貌改性以及表面的功能化,在许多领域有着广泛的应用.本文概述了紫外光引发接枝改性聚合物表面技术的研究进展,包括紫外光接枝聚合机理、接枝新方法和应用技术等.     

聚丙烯纤维的表面改性研究

本文采用化学氧化法和紫外引发接枝法分别对聚丙烯纤维进行了表面改性,接枝单体为丙烯酸。对改性后的聚丙烯纤维的化学结构、表面润湿性和力学性能进行了表征。实验结果表明,经接枝改性后的聚丙烯纤维表面引入了极性基团,亲水性能明显变好。     

聚合物表面紫外光接枝改性的研究

介绍聚合物表面紫外光接枝改性的研究方法,其中包括液相和气相接枝、接枝反应的引发方式及其机理,溶剂的影响和选择,针对不同改性要求对接枝单体的使用以及连续化操作的发展。此外,还简要介绍了聚合物表面接枝效果的测试方法和接枝后表面形态的观测方法     

紫外引发含氟单体在LDPE薄膜表面的接枝改性

研究紫外光引发甲基丙烯酸十二氟庚酯(DFHMA)在LDPE薄膜表面的接枝改性.考察辐照时间和距离,光敏剂浓度、紫外光强度对接枝率的影响.通过红外光谱分析、扫描电镜及能谱分析对接枝前后的薄膜表面进行表征,结果表明:DFHMA可以通过紫外引发接枝到LDPE等薄膜表面;并对接枝后薄膜的润湿性进行分析,结果表明:接枝含氟单体后薄膜表面能降低、润湿性减弱、接触角变大.     

超热氢交联技术对聚氯代对二甲苯膜表面润湿性的影响

为了解决聚氯代对二甲苯膜(PC膜)表面润湿性较差的问题,采用一种新的表面改性方法即超热氢交联技术(HHIC),引发亲水性高分子聚丙烯酸(PAA)在PC膜表面的接枝反应,从而提高其表面润湿性。实验采用接触角测试仪、傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和紫外可见光分光光度计对HHIC改性前后薄膜的润湿性、表面化学结构、表面物理形貌、薄膜透光率的变化进行了表征。结果表明,HHIC改性能够在PC薄膜表面有效地接枝具有极性官能团的PAA分子,导致改性后PC膜表面的接触角由最初的84°下降到23°。除此之外,改性后PC膜的透光率并没有明显下降,表明HHIC改性没有对PC膜本体造成物理性的破坏。     

炭黑亲水性改性的研究进展

从炭黑的元素组成和表面官能团出发,介绍了增强炭黑亲水性改性的3种方法:氧化改性、接枝改性和包覆改性。氧化改性分为气相氧化、液相氧化、阳极氧化和等离子体氧化,接枝改性分为捕获性接枝、引发性接枝和反应性接枝,包覆改性的方法有微乳液聚合包覆和相分离法包覆。亲水性改性后的炭黑对水的润湿性增强,在水中分散更稳定。     

功能化聚乙烯膜的制备及性能研究

以高压聚乙烯（LDPE）膜为原料，采用紫外光辐照引发LDPE膜表面接枝丙烯酸；研究发现，当接枝率达到2．5g/m^2时，丙烯酸接枝LDPE膜的润湿性达到平衡值；接枝改性后，LDPE膜的润湿性、透湿性都得到改善；IR光谱显示丙烯酸已成功接枝到LDPE膜上；DSC热分析显示接枝改性不影响LDPE膜材料的晶型结构。     

炭黑表面接枝聚合改性进展

从炭黑粒子表面性质及表面化学基团出发 ,并结合聚合反应理论 ,介绍了将单体接枝聚合或将聚合物直接接枝到炭黑表面的自由基接枝、正离子接枝、负离子接枝及其他功能化接枝改性方法。论述了实现这些过程的溶液法、熔融法及辐射法接枝等工艺方法及影响炭黑接枝改性的因素。炭黑表面接枝聚合改性能大大扩大炭黑的应用范围。     

聚合物表面光接枝改性研究进展

表面光接枝主要是用芳酮引发有机材料产生自由基，从而引发单体聚合产生表面接枝链。表面光接枝应用领域广泛．可用于聚合材料的表面改性以及表面功能化。综述了紫外光引发接枝改性聚合物表面的研究进展，包括光接枝聚合机理、改性方法、影响因素等，并对其应用前景及研究方向进行了介绍。     

聚丙烯的接枝改性技术

近年来,聚丙烯的化学改性研究引起了广泛的关注,其中以接枝改性为主。综述了聚丙烯接枝改性的几种常用方法,总结了聚丙烯接枝改性的机理、接枝单体的选择以及接枝产物的表征手段。     

PVA-g-mPEG接枝聚合物的制备及其防药物滥用性能

阿片类药物的滥用问题日益严重，目前防滥用制剂局限在以往已有的技术，在开发新材料方向却少有报道，为此本文通过分子设计提出以接枝改性的方法制备一种具有防滥用性能的新型PVA-g-mPEG接枝聚合物。以聚乙烯醇（PVA）、单甲氧基聚乙二醇（mPEG）和环氧氯丙烷（ECH）为原料，采用两步反应合成法制备聚乙烯醇/单甲氧基聚乙二醇的接枝聚合物（PVA-g-mPEG），研究了反应温度对接枝率的影响。通过傅里叶红外光谱、核磁共振氢谱、差示扫描量热法以及X射线衍射法对产物进行表征。另外，以盐酸二甲双胍为模型药物，制备了接枝聚合物骨架片，考察了材料的防滥用性能。结果表明：随着接枝率的升高（43.44%，81.23%，120.48%），在水中20min时分别有28.3%、20.8%和12.9%的药物被提取，表明接枝聚合物具有一定的防滥用效果，对开发新的防滥用药的药用辅料具有较好的指导作用。     

Functional biohybrid materials synthesized via surface-initiated MADIX/RAFT polymerization from renewable natural wood fiber: Grafting of polymer as non leaching preservative

Crude wood fibers represent a wide class of renewable resources. The surface modification of such materials via covalent grafting of polymer offers new surface properties with non-leaching coating. The grafting of the polymer chains was achieved by surface-initiated controlled radical polymerization through a grafted xanthate chain transfer agent. Macromolecular design via interchange of xanthate (MADIX) technique was chosen to graft poly(vinyl acetate), polystyrene, poly(n-butyl acrylate) and poly(4-vinylbenzyl chloride)-polystyrene amphiphilic cationic copolymers. Water contact angle measurements highlighted the hydrophobization of the wood fiber surface with a nanoscaled polymer monolayer indicating the appropriate coverage of the fiber. X-ray photoelectron spectroscopy showed the successful grafting of the polymer after drastic washing procedure. The quaternization of the grafted polystyrene-co-poly(4-vinyl benzyl chloride) copolymers with tertiary amine allows the introduction of biocide quaternary ammonium functions while preserving the hydrophobic character of the modified wood fiber when introducing a long alkyl chain in the statistical copolymer. Finally, the cationic copolymer was subjected to Coniophora Puteana to evaluate its propensity to limit the fungi expansion.     

丙烯酸丁酯原位乳液接枝纳米TiO2的研究

为了提高纳米二氧化钛（TiO2）粒予在聚合物基复合材料中的分散性,需要对粒子的表面进行改性。实验采用无皂乳液聚合法,使丙烯酸丁酯单体（BA）在偶联剂KH-570烷基化预处理的纳米TiO2粒子的表面进行接枝聚合,研究了偶联剂用量对烷基化预处理程度的影响,以及聚合条件对TiO2表面接枝效果的影响,并对其聚合机理进行了探讨。结果表明,PBA以化学键成功地接到纳米TiO2的表面,并且可以通过改变接枝聚合条件来调节粒子上所接聚丙烯酸丁酯的结构,为进一步优化纳米粒子填充聚合物复合材料的结构和性能之间的关系建立基础。     

Location of some typical vinyl polymers within radiation-grafted cotton fibers: An electron microscopical survey

Electron microscopical observations of radiation-induced rayon–styrene graft copolymers were published by Kaeppner and Huang in 1965. The present paper reports electron microscopical investigations on the relationship of the structure of vinyl–cotton graft polymers to the original morphology of the cotton fiber and into the distribution of the grafted vinyl polymer in the cotton fiber structure. The grafted vinyl monomers investigated in this study were acrylonitrile, styrene, methyl methacrylate, and vinyl acetate. Two radiation-induced procedures were used: simultaneous irradiation grafting and post-irradiation grafting. Ceric ion grafting of acrylonitrile to cotton was included for purposes of comparison. Distribution of the vinyl polymer within the cotton fiber is illustrated by a series of electron micrographs, selected as typical of the particular grafted species under consideration. Results indicate that the diffusion rate of monomer into the cellulose fiber plays an important role in the final distribution of polyacrylonitrile grafts within the fiber. Uniform distribution of polyacrylonitrile in the fiber was achieved by simultaneous irradiation grafting of acrylonitrile on a highly substituted cyanoethylated cotton. In samples of low degree of cyanoethylation the distribution of graft polymer was non-uniform. In grafting initiated by ceric ion the acrylonitrile graft polymer was evenly distributed. Polystyrene–cotton copolymers from grafts, made by simultaneous irradiation of cotton in methanol solutions of the styrene monomer, were uniform throughout the fiber but showed opening of structure associated with the amount of graft formed. Grafting of methyl methacrylate occurred only in the peripheral regions of the fiber; by contrast, grafting of vinyl acetate was uniform throughout the fiber wall. Important factors governing the successful irradiation grafting in cotton fibers are choice of solvent, ratio of monomer to cellulose, nature of prior chemical modification of the cellulose, and total irradiation dosage.     

尼龙材料的表面接枝改性

尼龙是一种综合性能优良、应用广泛的工程塑料。通过接枝方法对尼龙材料进行接枝改性，可实现尼龙材料的表面功能化。文章综述了近几年来尼龙表面接枝改性的研究进展，并对其应用前景进行了展望。     

Graft polymerization of vinyl acetate onto silica

The free‐radical graft polymerization of vinyl acetate onto nonporous silica particles was studied experimentally. The grafting procedure consisted of surface activation with vinyltrimethoxysilane, followed by free‐radical graft polymerization of vinyl acetate in ethyl acetate with 2,2′‐azobis(2,4‐dimethylpentanenitrile) initiator. Initial monomer concentration was varied from 10 to 40% by volume and the reaction was spanned from 50 to 70°C. The resulting grafted polymer, which was stable over a wide range of pH levels, consisted of polymer chains that are terminally and covalently bonded to the silica substrate. The experimental polymerization rate order, with respect to monomer concentration, ranged from 1.61 to 2.00, consistent with the kinetic order for the high polymerization regime. The corresponding rate order for polymer grafting varied from 1.24 to 1.43. The polymer graft yield increased with both initial monomer concentration and reaction temperature, and the polymer‐grafted surface became more hydrophobic with increasing polymer graft yield. The present study suggests that a denser grafted polymer phase of shorter chains was created upon increasing temperature. On the other hand, both polymer chain length and polymer graft density increased with initial monomer concentration. Atomic force microscopy–determined topology of the polymer‐grafted surface revealed a distribution of surface clusters and surface elevations consistent with the expected broad molecular‐weight distribution for free‐radical polymerization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 300–310, 2003