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15个乙烯—乙烯基化合物共聚物的取代基参数 总被引:1,自引:0,他引:1
本文应用取代基参数(SCS)方法处理了15个EV共聚物的^13CNMR谱,它们是:(1)乙烯α-烯烃共聚物,即乙烯-丙烯共聚物,乙烯-丁烯-1共聚物,乙烯4-甲基-1-戊烯共聚物,乙烯-己烯-1共聚物和乙烯-辛烯-1共聚物;(2)乙烯-含氧乙烯共聚物,即乙烯-甲基丙烯酸N,N-二甲基胺乙酯共聚物,乙烯-丙烯酸甲酯共聚物,乙烯-丙烯酸共聚物,乙烯-乙酸乙烯酯,乙烯-乙烯醇,乙烯-一氧化碳共聚物(EC 相似文献
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用自由基溶液降合方法制备一系列苯乙烯-丙烯酸甲酯线型共聚物,用核磁共振测定了苯基在共聚物中的百分比,在该共聚物的四氢呋喃溶液中,用三氟乙酸汞在共聚物的苯环上进行亲电取代反应,得到可溶性汞化共聚物,由于这类泵化共的可溶于四氢呋喃,二氯甲烷等溶剂,用重沉淀法多次提纯,得到了纯度很高,溶解性较好的含重金属二价汞的共聚物,用红外光谱仪测定共聚物上的汞基团,用原子吸收定量测试共聚中的汞的百分聚代率,结果表明 相似文献
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用自由基溶液聚合方法制备一系列苯乙烯-丙烯酸甲酯线型共聚物,用核磁共振仪测定了苯基在共聚物中的百分比.在该共聚物的四氢呋喃溶液中,用三氯乙酸汞在共聚物的苯环上进行亲电取代反应,得到可溶性汞化共聚物.由于这类汞化共聚物可溶于四氢呋喃、二氯甲烷等溶剂,用重沉淀法(Reprecipitation)多次提纯,得到了纯度很高、溶解性较好的含重金属二价录的共聚物.用红外光谱仪测定共聚物上的汞基因,用原子吸收仪定量测试共聚中的汞的百分取代率.结果表明在本文实验条件下,二价示可取代在苯环上,与丙烯酸甲酯基因没有作用. 相似文献
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本文采用氧化还原引发体系合成了丙烯腈与马来酸酐共聚物,各首次将此共聚物制成了醇,水分离用的渗透蒸发膜,研究了不同马来酸酐含量的共聚物膜碱中的水解规律,考察了共聚物,料液温度,料液浓度等条件对膜的醇,水分离性能的影响关系以及水解前,后膜性能的变化结果表明,当共聚物中马来酸酐含量大于0.069(摩尔分数)时,水解前,后膜性能有很大的变化,分离因子,渗透通量和膜强度都普遍提高。另外,还发现该共聚物膜与其 相似文献
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自交联型丙烯酸酯共聚物乳液的研究 总被引:7,自引:0,他引:7
以羟甲基丙烯酰胺、丙烯酸作为活性单体,采用种子乳液聚合法制得四元体系自交联型丙烯酸酯共聚物乳液。用透射电镜观察了乳胶粒的微观形态,并对共聚物乳液的流变性,稳定性等进行了测试,考察了羟甲基丙烯酰胺和丙烯酸的含量、聚合方式对共聚物乳液性能的影响。 相似文献
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含聚二甲基硅氧烷侧链的丙烯酸酯共聚物的研究 总被引:5,自引:0,他引:5
采用含活性基团的聚二甲基硅氧烷与丙烯酸酯进行自由基共聚合,合成了自聚二甲基硅氧烷侧链的丙烯酸酯共聚物。采用IR,^1H-NMR,GPC等分析方法对共聚物结构和组成进行了表征。通过接触角和X-射线光电子能谱对共聚物的表面性能和表面组成进行了研究,并通过粘接性能和破坏面形貌对共聚物与金属铝材和加成型硅橡胶的粘接性进行了探讨。 相似文献
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含氟丙烯酸酯共聚物制备超疏水表面及其形成机理的研究 总被引:7,自引:0,他引:7
以丙烯酸全氟烷基乙基酯和甲基丙烯酸甲酯为共聚单体, 分别以用微乳液聚合法和溶液聚合法制备的无规共聚物和用可逆加成-断裂链转移制备的嵌段共聚物作为成膜共聚物, 并以1,1,2-三氟三氯乙烷作为溶剂, 采用溶剂挥发成膜法可以直接制备出超疏水膜, 聚合物膜对水的接触角可达160°. 改变聚合物结构和成膜条件, 探讨了该类超疏水膜的形成机理和影响因素. 发现膜的表面形貌和疏水性与共聚物的组成、结构、分子量以及成膜条件密切相关, 随着共聚物中氟含量的增大, 膜的表面形貌都趋于平滑; 而且, 无规共聚物比嵌段共聚物更易形成粗糙度好的膜; 同时, 较大的聚合物分子量和适宜的高的成膜温度都对形成粗糙结构有利. 相似文献
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Masayasu Akiyama Mitsuaki Narita Makoto Okawara 《Journal of polymer science. Part A, Polymer chemistry》1969,7(5):1299-1306
Styrene-maleic anhydride alternating copolymer was converted to N-hydroxymaleimide-styrene copolymer by reaction with hydroxylamine in pyridine at room temperature. The conversion was more than 90%. From this copolymer, N-acetoxy- or N-benzoyloxymaleimide-styrene copolymers were derived by action of acetic anhydride or benzoyl chloride in dimethylformamide at room temperature. Acylation of several primary amines was carried out effectively by use of these N-acyloxyimide-styrene copolymers. The reaction of the acetylated copolymer with diethylamine at room temperature afforded N-hydroxyimide copolymer. 相似文献
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利用耗散粒子动力学模拟研究了在水溶液中混合不同的线形三嵌段共聚物AxByCz和线形两嵌段共聚物AmBn对多室胶束的形貌多样性的影响.通过改变线形的三嵌段共聚物和两嵌段共聚物的链长来寻找多室胶束的形成条件.由线形三嵌段共聚物和线形两嵌段共聚物的不同混合形成的多室胶束结构是多种多样的,例如"蠕虫状"胶束、"汉堡包"胶束、"球上球"胶束、"核-壳-壳"胶束等等.多室胶束的整体形貌和内部结构的控制都可以从线形三嵌段共聚物和两嵌段共聚物的二元共混得到.为了表征获得的多室胶束结构,我们计算了密度图和成对分布函数图.在此工作中,可以获得和观察到复杂的多室胶束.结果表明,简单地混合线形的三嵌段共聚物和线形的两嵌段共聚物是一个控制多室胶束形貌和结构的有效方法,在工程实验中可以更简单更经济地形成多室胶束结构.因此,在设计新的多室胶束方面,聚合物共混仍然是未来值得更加关注的一个话题. 相似文献
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Anti-microbial activity of anhydride copolymers and their derivatives prepared by ionizing radiation
Methyl methacrylate/maleic anhydride (MMA/MAn) copolymers were synthesized using gamma rays. Preparation conditions such as irradiation dose, comonomer composition and type of diluent affecting the degree of comonomer conversion were investigated. The suitable diluent for obtaining reasonable MMA/MAn copolymer yield was acetone. The higher copolymer yield was achieved when the amount of methyl methacrylate in comonomer feed solutions as well as irradiation dose increased. The effect of ZnCl2 on the MMA/MAn copolymer yield and structure was studied. Characterization of the prepared MMA/MAn copolymers was performed using FTIR, and thermogravimetric and viscometric analysis. The derivatives of MMA/MAn copolymers were obtained by treating them with different reagents such as sulpha-drugs, hydroxylamine hydrochloride and 4-amino sodium salyciliate. The antimicrobial activity of MMA/MAn copolymers and their derivatives was examined. The activity of such copolymers against Staphylococcus aureus and Escherichia coli increased by increasing MAn content in the copolymer. The MMA/MAn copolymers treated with sulpha-drugs exhibited particularly high biological activity against different microorganisms. These results revealed that the prepared MMA/MAn copolymer and its derivatives have a broad antimicrobial activity. 相似文献
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The Mobility of Threaded α-Cyclodextrins in PR Copolymer and Its Influences on Mechanical Properties
The methylated polyrotaxane(Me PR) copolymer was prepared via the methylation of hydroxyl of threaded α-cyclodextrin(α-CDs) in polyrotaxane(PR) copolymer by CH_3I/Na H. Its structure was characterized by GPC, IR and NMR. The WXRD and TGA measurements showed the destruction of channel-like crystalline structure in Me PR copolymer. The sliding of threaded α-CDs along PEG axis in PR and Me PR copolymers was demonstrated by their dielectric spectra that also evidenced the presence of rotating of threaded α-CDs around PEG axis in Me PR copolymer. The frequent and vigorous molecular mobility in Me PR and PR copolymers was also verified by dynamic mechanical analysis(DMA) and rheological measurement, which was possibly assigned to the sliding and rotating of threaded α-CDs. DMA and rheological results showed that the mobility of α-CDs could simultaneously strengthen and toughen PR copolymer proved by stress-stain curves. In this paper, we report the CD mobility in PR and Me PR copolymers. The macroscopic behaviors of PR copolymer, such as mechanical properties in solid state, were also found to be benefited from CD mobility. 相似文献
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In this study, the adsorption of amphiphilic poly(ethylene oxide)-block-polylactide (mPEO-PLA) copolymers from a selective solvent onto a polylactide surface was studied as a method of polylactide surface modification and its effect on nonspecific protein adsorption was evaluated. A series of well defined mPEO-PLA copolymers was prepared to investigate the effect of copolymer composition on the resulting PEO chain density and on the surface resistance to protein adsorption. The copolymers contained PEO blocks with molecular weights ranging between 5600 and 23,800 and with 16-47 wt% of PLA. The adsorption of both the copolymers and bovine serum albumin was quantified by attenuated total reflection FTIR spectroscopy (ATR-FTIR). In addition to the adsorbed copolymer amount, its actual composition was determined. The PEO chain density on the surface was found to decrease with the molecular weight of the PEO block and to increase with the molecular weight of the PLA block. The adsorbed copolymers displayed the ability to reduce protein adsorption. The maximum reduction within the tested series (by 80%) was achieved with the copolymer containing PEO of MW 5600 and a PLA block of the same MW. 相似文献
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Gary H. Van Domeselaar Glen S. Kwon Lena C. Andrew David S. Wishart 《Colloids and surfaces. B, Biointerfaces》2003,30(4):323-334
This work describes a simple, versatile solid-phase peptide-synthesis (SPPS) method for preparing micelle-forming poly(ethylene oxide)-block-peptide block copolymers for drug delivery. To demonstrate its utility, this SPPS method was used to construct two series of micelle-forming block copolymers (one of constant core-composition and variable length; the other of constant core length and variable composition). The block copolymers were then used to study in detail the effect of size and composition on micellization. The various block copolymers were prepared by a combination of SPPS for the peptide block, followed by solution–phase conjugation of the peptide block with a proprionic acid derivative of poly(ethylene oxide) (PEO) to form the PEO-b-peptide block copolymer. The composition of each block component was characterized by mass spectrometry (MALDI and ES-MS). Block copolymer compositions were characterized by 1H NMR. All the block copolymers were found to form micelles as judged by transmission electron microscopy (TEM) and light scattering analysis. To demonstrate their potential as drug delivery systems, micelles prepared from one member of the PEO-b-peptide block copolymer series were physically loaded with the anticancer drug doxorubicin (DOX). Micelle static and dynamic stability were found to correlate strongly with micelle core length. In contrast, these same micellization properties appear to be a complex function of core composition, and no clear trends could be identified from among the set of compositionally varying, fixed length block copolymer micelles. We conclude that SPPS can be used to construct biocompatible block copolymers with well-defined core lengths and compositions, which in turn can be used to study and to tailor the behavior of block copolymer micelles. 相似文献
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模板聚合法合成P(AM/AA)多嵌段共聚物的溶液性质和自缔合作用 总被引:1,自引:0,他引:1
研究了模板法合成多嵌段状丙烯酰胺(AM)和丙烯酸(AA)共聚物(简称模板共聚物TP)在水溶液中的溶液性质和缔合作用.结果表明,模板共聚物具有明显的结构效应.不同于无模板参与聚合的无规共聚物(CP),模板共聚物随着溶液pH的降低或加入多价金属离子容易发生相分离.透射电子显微镜(TEM)表明,加入Ca2+离子后,聚合物形成了大的分子间交联体,且随着Ca2+离子浓度的增加,交联程度增加,致使溶液产生相分离.随着溶液pH的升高,模板共聚物溶液粘度变化与丙烯酸均聚物具有相同的规律,都是先增大后减小,粘度有一个最大值,但模板共聚物溶液粘度升高幅度更大.TEM表明在粘度最大处形成了带状分子间缔合体. 相似文献
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聚丁二烯-b-甲基丙烯酸甲酯共聚物的聚集态研究周庆业,张邦华,宋谋道,何炳林(南开大学高分子化学研究所,天津,300071)关键词共聚物,相分离,聚集态结构嵌段共聚物按其组成、合成及成型条件的不同可形成丰富的相结构[1],其动态力学性能,如在损耗模量... 相似文献