胰蛋白酶分子表面印迹材料的制备及其大分子识别特性

以交联聚乙烯醇(CPVA)微球为基质,采用接枝聚合和表面印迹同步技术制备碱性蛋白胰蛋白酶(TRY)分子表面印迹材料,甲基丙烯酰氯与CPVA微球表面的羟基发生快速酯化反应,得到表面含大量可聚合双键甲基丙烯酰基(MAO)的改性微球MAO-CPVA. 按一定摩尔比将TRY和单体阴离子单体对苯乙烯磺酸钠(SSS)溶解在水溶液中,加入交联剂N,N'-亚甲基双丙烯酰胺(MBA), MAO-CPVA分散于水介质中,过硫酸铵/亚硫酸氢钠引发体系产生自由基,使包围在TRY周围的单体SSS与MBA在MAO-CPVA表面发生接枝交联聚合,制得TRY表面印迹微球MIP-PSSS/CPVA,对其进行表征,考察了其大分子识别性能. 结果表明,MIP-PSSS/CPVA对TRY有优良的亲和性和特异识别选择性,吸附容量达85.9 mg/g,对TRY的选择性系数相对于蛋白溶菌酶LZM达17.52.     

交联PS微球表面PEMA刷子的合成与表征

将含有双键的N，N-二甲氨基甲基丙烯酸乙酯化学锚接在交联聚苯乙烯（PS）微球表面,再用过氧化苯甲酰引发甲基丙烯酸乙酯（EMA）氮氧调控自由基原位接枝聚合反应．将聚甲基丙烯酸乙酯（PEMA）接枝在交联PS微球表面，制备了PEMA刷子层；研究了聚合反应机理．并对所合成交联PS接枝PEMA共聚物进行了表征。结果表明，在2，2，6．6-四甲基哌啶-1-氧自由基存在下，EMA的聚合反应为“活性”自由基聚合．所得到的PEMA摩尔质量分布在1．18—1．3范围，摩尔质量随聚合时间的延长而增大（9000～57000g／mol）；红外光谱显示PEMA被接枝到了交联PS微球表面，交联PS微球粒径在0．5—1．2μm之间。     

交联PMMA微球表面PS刷子的合成与表征

将含有双键的甲基丙烯酸-2-氨基乙酯化学锚接在交联聚甲基丙烯酸甲酯微球表面,然后用过氧化苯甲酰引发苯乙烯发生氮氧调控自由基原位接枝聚合反应,将聚苯乙烯接枝在交联聚甲基丙烯酸甲酯微球表面,制备了PS刷子层.用凝胶渗透色谱和红外光谱对所合成交联聚苯乙烯接枝聚甲基丙烯酸乙酯共聚物进行了表征,实验结果显示：在2,2,6,6-四甲基哌啶-1-氧自由基存在下,苯乙烯的聚合反应为＂活性＂自由基聚合,所得到的聚苯乙烯分子量分布在1.13～1.28范围,分子量随聚合时间的延长而增大（7 000～68 000 g/mol）.接枝聚合物红外光谱显示聚苯乙烯被接枝到了交联聚甲基丙烯酸甲酯微球表面.AFM 表征显示交联聚甲基丙烯酸甲酯微球尺寸在0.3～1.6 μm 范围.     

由CPVA-g-PSSS功能接枝微球构建pH依赖型5-ASA结肠定位释药体系

采用铈盐-羟基氧化还原引发体系,在交联聚乙烯醇(CPVA)微球表面引发接枝聚合对苯乙烯磺酸钠(SSS),制备了接枝聚阴离子的功能接枝微球CPVA-g-PSSS,研究了其对5-氨基水杨酸(5-ASA)的吸附(载药)性能、机理和释放行为. 结果表明,在酸性介质中,受强静电相互作用驱动,CPVA-g-PSSS对5-ASA分子表现出很强的吸附能力,吸附容量达39.1 mg/g,可实现有效载药. 载药微球的释药行为具有强烈的pH值依赖性, 在pH=1的介质中基本不释药,而在pH=7.4的介质中发生突释,释放率可达86%,表现出良好的结肠定位释放行为.     

表面接枝高密度磺酸基聚苯乙烯的制备及表征

以无水溴化铝为催化剂,对氯苯甲醛为醛基化试剂,通过傅克反应在聚苯乙烯微球表面接枝醛基;基于醛基的可氧化性,利用还原剂硝酸铵铈将树脂微球表面的醛基自由基化,引发对苯乙烯磺酸钠在树脂微球表面聚合,并对其进行表征。结果表明,聚苯乙烯微球磺酸化改性成功,优化的磺化工艺条件为:醛基含量1.5 mmol/g的聚苯乙烯微球用量0.3 g,对苯乙烯磺酸钠质量浓度40 g/L,硝酸铵铈质量浓度40 g/L,反应温度70℃,在此条件下制备的树脂表面磺酸基含量为58 mmol/g。     

反相悬浮-化学交联法制备聚乙烯醇交联微球CPVA

以聚乙烯醇(PVA)为单体,戊二醛(GA)为交联剂,山梨醇酐单硬脂酸酯(span60)为分散剂,采用反相悬浮一化学交联法,制备了聚乙烯醇交联微球CPVA,采用FT-IR和SEM对其化学结构和微观形貌进行了表征,考察了搅拌速率、交联剂的用量、催化剂(盐酸)的用量对交联微球的成球性能及粒度的影响规律.结果表明,在反相悬浮体系中,搅拌速度、交联剂的用量是影响交联微球制备的主要因素,当搅拌速度小于250r/min、交联剂的用量大于2ml时,体系中均不能成球.在体系中加入盐酸后,交联微球的粒径随盐酸用量的增大而增大.控制成球的反应条件可以制备出球形度良好、粒径在150μm左右的粒径可控的聚乙烯醇交联微球CPVA.     

阴离子型PSSS/PSA微球的制备及对谷氨酸的吸附性能初探

在溶液聚合体系中,采用自由基聚合法将功能单体对苯乙烯磺酸钠(SSS)接枝于聚苯乙烯伯胺微球微粒(PSA)表面,制得了接枝微粒PSSS/PSA,考察了主要因素对接枝聚合的影响,并初步研究了其对L-谷氨酸的吸附特性。已接枝到聚苯乙烯伯胺微球微粒表面的聚合物层,会对后续的接枝聚合产生阻隔作用;温度及引发剂用量等因素显著影响接枝度。在优化条件下:温度50℃,单体质量1.046 4 g (溶液质量分数的2.22%),引发剂用量0.060 0 g (占单体的质量分数5.73%),可制得接枝度为230.27 mg·g-1的接枝微粒。其吸附量达120 mg·g~(-1)。     

反相悬浮—化学交联法制备聚乙烯醇交联微球CPVA

以聚乙烯醇（PVA）为单体,戊二醛（GA）为交联剂,山梨醇酐单硬脂酸酯（span-60）为分散剂,采用反相悬浮-化学交联法,制备了聚乙烯醇交联微球CPVA。采用FT-IR和SEM对其化学结构和微观形貌进行了表征,考察了搅拌速率、交联剂的用量、催化剂（盐酸）的用量对交联微球的成球性能及粒度的影响规律。结果表明,在反相悬浮体系中,搅拌速度、交联剂的用量是影响交联微球制备的主要因素,当搅拌速度小于250r/min、交联剂的用量大于2mL时,体系中均不能成球。在体系中加入盐酸后,交联微球的粒径随盐酸用量的增大而增大,控制成球的反应条件可以制备出球形度良好、粒径在150μm左右的粒径可控的聚乙烯醇交联微球CPVA。     

本体连续法制备高抗冲聚苯乙烯树脂引发体系的研究

利用平推流反应器和连续本体聚合方法,制备了高抗冲聚苯乙烯树脂(HIPS)。分别研究了热引发体系和自由基引发体系下,HIPS树脂制备过程中的橡胶相接枝反应和PS相的形成过程,以及对HIPS性能的影响。结果表明,对于热引发体系而言,橡胶相的接枝反应主要存在于第一反应器和第二反应器的4区,PS相的形成主要存在于第二反应器的5、6区和第三、第四反应器;对于自由基引发体系,橡胶相接枝反应和PS的聚合反应在低于热引发体系的温度下进行,接枝反应则主要发生于第一、第二反应器,PS相的形成主要在第三、第四反应器中进行。反应初期温度降低有利于橡胶相接枝反应,而反应后期温度升高则利于高摩尔质量PS的制备,自由基引发体系制备的HIPS性能更加优良。     

新型脂肪族磺酸基强酸型阳离子交换树脂的合成

以2-丙烯酰胺-2-甲基丙磺酸(AMPS)为单体、CuCl/N,N,N′,N′-四甲基乙二胺(TMEDA)为催化体系,氯乙酰化聚苯乙烯微球(PS-acyl-Cl)为大分子引发剂,经原子转移自由基聚合反应(ATRP),于微球表面接枝聚脂肪族磺酸(PAMPS)链段获得脂肪族磺酸基强酸性阳离子交换树脂(PS-g-PAMPS).考察了反应温度、溶剂体系、pH 值、催化剂、反应时间等条件对接枝反应的影响,在优化的反应条件下,使用氯乙酰基担载量为3.82 mmol?g?1的 PS-acyl-Cl,10 h 可获得担载量为1.99 mmol?g?1的 PS-g-PAMPS.产物经过红外,元素分析表征.该 PS-g-PAMPS 较传统的磺酸基树脂有较长的手臂长度,位阻小,易于和其它物质反应,TG 分析显示具有很好的热稳定性.     

Preparation of poly(vinyl amine)‐grafted crosslinked poly(vinyl alcohol) microspheres

Crosslinked poly(vinyl alcohol) (CPVA) microspheres were first prepared via the suspension polymerization of vinyl acetate and the alcoholysis of poly(vinyl acetate). Afterwards, a two‐step method involving graft polymerization and Hofmann degradation was used to prepare functional poly(vinyl amine)‐grafted crosslinked poly(vinyl alcohol) (PVAm–CPVA) microspheres, onto which poly(vinyl amine) (PVAm) macromolecules were grafted. The graft polymerization of acrylamide (AM) on CPVA microspheres was performed with cerium salt as the initiator in an acidic aqueous medium, resulting in polyacrylamide (PAM)‐grafted CPVA microspheres. Subsequently, the grafted PAM was transformed into PVAm via the Hofmann degradation reaction, and PVAm–CPVA microspheres were prepared. The effects of the main factors on the graft polymerization and Hofmann degradation were examined, and the reaction mechanisms were researched in depth. The experimental results showed that for the graft polymerization of AM on CPVA microspheres initiated by cerium salt, the acid concentration and the amount of cerium salt affected the grafting degree of PAM greatly. For the Hofmann degradation reaction of the grafted PAM, the amination degree of PVAm–CPVA microspheres was obviously affected by the amount of sodium hypochlorite in the presence of sodium hydroxide. The preliminary adsorption tests showed that PVAm–CPVA microspheres were multifunctional and had strong adsorption ability for Fe(III) ions by chelation action and for chromate ions (CrO) by strong electrostatic interactions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Preparation and recognition performance of cholic acid-imprinted material prepared with novel surface-imprinting technique

Acrylamide (AM) was first graft-polymerized on the surface of crosslinked polyvinyl alcohol (CPVA) microspheres by initiating of cerium salt, and then the grafted polyacrylamide (PAM) was transformed to polyvinylamine (PVAm) via Hofmann degradation reaction, resulting in the grafted microspheres PVAm/CPVA. By adopting the novel surface molecular imprinting technique put forward by us, cholic acid molecule-imprinted material MIP-PVAm/CPVA was prepared with glutaraldehyde as crosslinking agent The binding character of MIP-PVAm/CPVA towards cholic acid molecules was studied in depth with both batch and column methods and using cholesterol as a contrast compound whose chemical structure is similar with cholic acid to a certain extent. The experimental results show that the surface-imprinted material MIP-PVAm/CPVA has excellent binding affinity and recognition selectivity for the template molecule, cholic acid. The selectivity coefficient of PVAm/CPVA microspheres (non-imprinting material) for cholic acid relative to cholesterol is only 1.314, displaying very poor recognition selectivity for cholic acid. However, after imprinting, the selectivity coefficient of MIP-PVAm/CPVA for cholic acid in respect to cholesterol is remarkably enhanced to 11.231, displaying the excellent recognition selectivity and binding affinity towards cholic acid molecules. Besides, MIP-PVAm/CPVA microspheres have fine desorption property, and by using a mixture of ethanol and NaOH aqueous solution as an eluent, the desorption ratios can reach 99.73% as the effluent amount gets up to 20 bed volumes (BV).     

AMPS接枝聚乙烯醇高吸水性树脂的合成

采用水溶液聚合,过硫酸钾-亚硫酸氢钠氧化-还原复合引发体系,以聚乙烯醇(PVA)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为原料,合成AMPS接枝聚乙烯醇高吸水树脂。考察了共聚反应的聚合温度、单体配比、中和度、交联剂、引发剂用量、反应时间等对吸水率的影响。所合成的树脂吸水率达382.2 g/g,吸0.9%NaCl溶液最大为82.7 g/g。     

反相悬浮聚合法制备XG-g-PAA高吸水性树脂

采用黄原胶(XG)为基体,丙烯酸(AA)为接枝聚合单体,环己烷为连续相,过硫酸钾为引发剂,利用反相悬浮聚合法合成了XG-g-PAA高吸水性树脂。研究了丙烯酸与黄原胶质量比、引发剂(KPS)用量、交联剂(NMBA)用量、丙烯酸中和度和聚合反应温度等因素对树脂吸水率的影响。利用傅立叶变换红外光谱仪(FTIR)、扫描电镜(SEM)和热重分析仪(TGA)对产物进行了表征。结果表明,丙烯酸与黄原胶发生接枝共聚,在最佳工艺条件下制备的XG-g-PAA高吸水性树脂具有良好的吸水和抗盐性能,高温保水性能提高,对蒸馏水的吸水率为845 g.g-1,对质量分数0.9%的NaCl水溶液的吸水率为96.3 g.g-1,接枝率达126.5%,接枝效率达82.6%。     

麦秸秆纤维素与丙烯酸接枝共聚制备耐盐性吸水树脂的研究

应用小麦秸秆与丙烯酸接枝共聚制备了耐盐性吸水树脂,进行了结构表征,研究了单体配比、丙烯酸中和度、引发剂和交联剂用量以及反应温度对吸盐水倍率的影响。研究发现,接枝共聚的适宜条件为:丙烯酸单体与麦秸秆质量比为8∶1,丙烯酸中和度为70%,引发剂过硫酸钾-硫代硫酸钠的用量为单体的3.5%,交联剂N,N-亚甲基双丙烯酰胺用量为单体质量的0.24%,反应温度为70℃。在此条件下制备的树脂吸盐水倍率最高,吸盐水(CNaC l=0.9%)可达68 g/g,可应用于医疗卫生等方面。     

铈盐引发高吸附量氨基化PGMA高分子微球合成及去除废水中Cr(VI)(英文)

A novel polyglycidylmethacrylate(PGMA) microspheres with high adsorption capacity of Cr(VI) was prepared by cerium(IV) initiated graft polymerization of tentacle-type polymer chains with amino group on polymer microspheres with hydroxyl groups.The micron-sized PGMA microspheres were prepared by a dispersion polym-erization method and subsequently modified by ring-opening reaction to introduce functional hydroxyl groups.The polymer microspheres were characterized by scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR).The results indicated that the polymer microspheres had an average diameter of 5 μm with uniform size distribution.The free amino group content was determined to be 5.13 mmol?g?1 for g-PGMA-NH2 mi-crospheres by potentiometric and conductometric titration methods.The Cr(VI) adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce adsorbents with high adsorption capacity(500 mg?g?1).The polymer microspheres with grafted tentacle polymer chains have poten-tial application in large-scale removal of Cr(VI) in aqueous solution.     

魔芋超强吸水剂的合成及吸液性能研究

以过硫酸钾为引发剂,N,N＇-亚甲基双丙烯酰胺为交联剂,采用水溶液自由基聚合法,合成了魔芋粉-丙烯酸（钠）-丙烯酰胺超强吸水剂。采用均匀试验设计法对该合成工艺进行优化,最佳工艺条件为单体总用量（单体/魔芋粉）8.79 g·g-1、引发剂量（引发剂/魔芋粉）4.50%、反应温度66.7℃、交联剂量（交联剂/魔芋粉）1.42%、反应时间2.55 h、丙烯酸中和度81.74%、单体比例51.7%。产物吸水率为751.3 g·g-1,吸盐水率为128.6 g·g-1。