固载化聚乙二醇树脂的合成及其接肽性能研究

聚乙二醇在浓氢氧化钠溶液中接枝到氯甲基化聚苯乙烯树脂上,制成了具有亲水性的固载化聚乙二醇树脂.讨论了各种反应条件对接枝反应产率的影响.用合成的树脂作载体,测定了合成多肽的反应动力学及缩合产率.与氯甲基化聚苯乙烯树脂相比,提高了合成多肽的反应速率及缩合产率.     

聚苯乙烯树脂固载聚乙二醇及吡啶weng盐的合成及其活性评价

以氯甲基化聚苯乙烯为原料，先后接枝聚乙二醇及吡啶，合成了双中心固载相转移催化剂──交联聚苯乙烯固载聚乙二醇４００及吡啶weng盐，并对氯甲基化聚苯乙烯树脂、聚苯乙烯固载聚乙二醇树脂、聚苯乙烯固载吡啶weng盐树脂及双中心树脂进行了红外光谱测试和分析，通过醋酸钾与溴节的反应，对各催化剂进行了活性评价，发现固载双中心相转移催化剂的活性明显高于各单中心固载相转移催化剂。     

聚苯乙烯树脂固载聚乙二醇及吡啶翁盐的合成及其活性评价

以氯甲基化聚苯乙烯为原料，先后接枝聚乙二醇及吡啶，合成了双中心固载相转移催化剂－交联聚苯乙烯固载聚乙二醇400及吡啶翁盐，并对氯甲基化聚苯乙烯树脂、聚苯乙烯固载聚乙二醇树脂、聚苯乙烯固载吡啶翁盐树脂及双中心树脂进行了红外光谱测试和分析。通过醋酸钾与溴苄的反应，对各催化剂进行了活性评价。发现固载双中心相转移催化剂的活性明显高于各单向中心固载相转移催化剂。     

聚乙二醇-聚苯乙烯接枝共聚物的合成及其接肽反应性能

本文应用环氧乙烷在羟乙基树脂上的开环聚合方法,合成了凝胶和大孔型聚乙二醇-聚苯乙烯接枝共聚物(简称PEG树脂)。对不同类型载体的接肽反应动力学性能研究表明,在PEG树脂载体上的反应速度是在氯甲基化树脂上的三倍,与在溶液中进行的接肽反应速率相当。此外,还对载体性能与树脂交联度、骨架结构之间的关系进行了初步探索。     

聚苯乙烯负载聚乙二醇在合成碳酸亚丙酯上的应用

用金属钾、金属钠以及氢氧化钠水溶液等方法制备了聚苯乙烯负载聚乙二醇，结果表明，采用金属钾比金属钠具有更好的接枝效果，并能使反应在较低的温度下较快地进行，而在氢氧化钠溶液中添加少量相转移剂，如Bu4NBr，接枝效果也有所提高。以聚苯乙烯负载聚乙二醇和KI为催化剂，研究了溶剂、温度等因素对CO2、环氧丙烷合成碳酸亚雨酯催化活性的影响。结果表明，选择甲醇为溶剂催化活性较高。研究还表明，聚苯乙烯负载聚乙二醇具有较高的热稳定性，可以在150℃下重复使用至少5次。     

聚苯乙烯负载聚乙二醇在合成碳酸亚丙酯上的应用

用金属钾、金属钠以及氢氧化钠水溶液等方法制备了聚苯乙烯负载聚乙二醇，结果表明，采用金属钾比金属钠具有更好的接枝效果，并能使反应在较低的温度下较快进行，而在氢氧化钠溶液中添加少量相转移剂，如Bu_4NBr，接枝效果也有所提高。以聚苯乙烯负载聚乙二醇和KI为催化剂，研究了溶剂、温度等因素对CO_2、环氧丙烷合成碳酸亚丙酯催化活性的影响。结果表明，选择甲醇为溶剂催化活性较高。研究还表明，聚苯乙烯负载聚乙二醇具有较高的热稳定性，可以在150℃下重复使用至少5次。     

聚苯乙烯负载聚乙二醇在合成碳酸亚丙酯上的应用

用金属钾、金属钠以及氢氧化钠水溶液等方法制备聚苯乙烯负载聚乙二醇，结果表明，采用金属钾比金属钢具有更好的接枝效果，并能使反应在较低的温度下较快进行。在氢氧化钠溶液中添加少量相转移剂，如Bu4NBr，接枝效果也有所提高。以聚苯乙烯负载聚乙二醇和KI一起为催化剂，研究了溶剂、温度等因素对CO2与环氧丙烷合成碳酸亚丙酯催化活性的影响。结果表明，以甲醇为溶剂催化活性较高。研究还表明，聚苯乙烯负载聚乙二醇具有较好的热稳定性，可以在150℃下重复使用至少5次。     

聚苯乙烯负载交联β—环糊精的合成与表征

β－环糊精有氢氧化的钠或氢化钠存在下和相转移催化剂作用下固载到氯甲基化矛苯乙烯树脂上，制成聚苯乙烯固载环糊精树脂，溶液中过量的β－环糊精钠盐与环氧氯丙烷共聚接枝到固载的环糊精树脂上，制备出一类新型的接枝聚合物。以正交实验设计法研究了不同反应体系载休骨交联度或含氯量、反应时间、温度、催化剂种类及抗料比等对固载化反应的影响，讨论了影响接枝反应的条件，对反应结果进行了红外光谱、扫描电镜分析，考察了该树脂     

PS-TEPA和PS-g-PEG树脂固载淀粉酶

聚苯乙烯四乙烯五胺树脂;聚苯乙烯-g-聚乙二醇树脂;α-淀粉酶;固定化;性能     

添加型聚丙烯大分子表面改性剂PP-g-PEG的制备及其应用

以马来酸酐为桥联剂,通过其与单端羟基聚乙二醇的反应,合成了大分子表面改性剂聚丙烯-聚乙二醇接枝共聚物,探索了反应条件对接枝反应的影响,用IR、NMR、TGA、DSC对接枝物的结构及性能进行研究,并通过共混研究了接枝物对聚丙烯的表面改性效果.结果表明,提高马来酸酐接枝聚丙烯或聚乙二醇的分子量,会阻碍接枝反应的进行,接枝率明显下降;接枝聚乙二醇降低了接枝物的结晶能力;聚丙烯-聚乙二醇接枝共聚物的热稳定性随着聚乙二醇的含量增加及侧链聚乙二醇长度的增加略有下降;聚丙烯-聚乙二醇接枝共聚物组分在共混物中具有明显的向外择优迁移特性,可以作为聚丙烯的添加型表面改性剂使用.     

Synthesis of cross-linked polystyrene-supported polyethylene glycol and investigation of its property in peptide synthesis

The polyethylene glycol resin (PEG-Resin) which possesses hydrophilic properties was prepared by grafting the polyethylene glycol onto the chloromethylated copolymer of styrene and divinylbenzene in the presence of concentrated sodium hydroxide solution. The proceeding of the graft reaction was identified by IR spectrum analysis. There factors which affected the grafting reactions were investigated. By using the PEG-Resin polymer support, we compared the reactions for the syntheses of a tetra-peptide and a penta-peptide with the Merrifield solid peptide synthesis. We also measured the reaction kinetics of these reactions. The experimental results showed that by employing the PEG-Resin, the reaction rates and condensation yields of these peptide syntheses were improved.     

二醋酸纤维素 -聚乙二醇接枝共聚物的核磁共振表征

用^1H NMR和^13C NMR核磁共振技术研究了二醋酸纤维素和聚乙二醇的接枝反应,并确定了^1H NMR和^13C NMR谱中各谱峰的归属,为证明二醋酸纤维素和聚乙二醇的接枝反应提供了依据。     

Post-synthesis modification of polyethersulfone membrane by grafting hyperbranched polyethylene glycol for oily wastewater treatment

Research on Chemical Intermediates - The main goal of this study is to modify the polyethersulfone membrane by the grafting hyperbranched polyethylene glycol (HB-PEG) via a two-step grafting...     

Comparison of the migration behavior of nanoparticles based on polyethylene glycol and silica using micellar electrokinetic chromatography

Nanoparticles, spherical particles with diameters less than 100 nm, are promising theranostic devices for noninvasive diagnosis and therapy. In this study, nanoparticles composed of polyethylene glycol and silica were prepared, and their migration behavior was examined using capillary electrophoresis. The effects of the sodium dodecyl sulfate concentration in the electrolyte, the nanoparticle size, and the encapsulated molecule on the migration were examined. The addition of sodium dodecyl sulfate into the electrolyte had a significant effect on the electrophoretic mobility of polyethylene glycol nanoparticles, but a small effect on that of silica nanoparticles. As for the size effect, the mobility became a little faster for smaller nanoparticle sizes for both polyethylene glycol and silica nanoparticles. The encapsulated molecule affected the mobility of the nanoparticles through interactions between the encapsulated molecules and sodium dodecyl sulfate. We propose that the large effect of sodium dodecyl sulfate on the migration of the polyethylene glycol nanoparticles was due to the large spaces within the nanoparticles. These results indicate that nanoparticle migration is mainly determined by the nanoparticle components.     

Synthesis of sodium allyl sulfonate in an aqueous medium by micellar catalysis with methoxy polyethylene glycol methacrylates

Micellar catalysis with various polyoxyethylated compounds was used to synthesize sodium allyl sulfonate by the reaction of allyl chloride with an aqueous solution of sodium sulfite. It was shown that methoxy polyethylene glycol methacrylates and water soluble polymers based on these compounds are surfactants and can be used to intensify the synthesis of sodium allyl sulfonate, which is of interest in the case of its subsequent application to obtain copolymers with methoxy polyethylene glycol methacrylates.     

Purification of papain by metal affinity partitioning in aqueous two‐phase polyethylene glycol/sodium sulfate systems

A simple and inexpensive aqueous two‐phase affinity partitioning system using metal ligands was introduced to improve the selectivity of commercial papain extraction. Polyethylene glycol 4000 was first activated using epichlorohydrin, then it was covalently linked to iminodiacetic acid. Finally, the specific metal ligand Cu²⁺ was attached to the polyethylene glycol‐iminodiacetic acid. The chelated Cu²⁺ content was measured by atomic absorption spectrometry as 0.88 mol/mol (polyethylene glycol). The effects on the purification at different conditions, including polyethylene glycol molecular weight (2000, 4000, and 6000), concentration of phase–forming components (polyethylene glycol 12–20% w/w and sodium sulfate 12–20%, w/w), metal ligand type, and concentration, system pH and the commercial papain loading on papain extraction, were systematically studied. Under optimum conditions of the system, i.e. 18% w/w sodium sulfate, 18% w/w polyethylene glycol 4000, 1% w/w polyethylene glycol‐iminodiacetic acid‐Cu²⁺ and pH 7, a maximum yield of 90.3% and a degree of purification of 3.6‐fold were obtained. Compared to aqueous two phase extraction without ligands, affinity partitioning was found to be an effective technique for the purification of commercial papain with higher extraction efficiency and degree of purification.     

The effect of additives on radiation-induced grafting of AA and SSS onto HDPE

A kind of ion-exchange membrane with strong acid and weak acid groups was prepared by radiation-induced grafting of acrylic acid (AA) and sodium styrene sulfonate (SSS) onto high-density polyethylene membrane (HDPE). The effect of additives such as sodium acetate, sodium chloride on grafting yield was studied. It was found that for either pre-irradiation method or simultaneous radiation method, the weak acid salt of strong alkali sodium acetate had a complex effect on the grafting yield by “pH effect” and “ion pair effect”, and the neutral salt sodium chloride was helpful to the increase of grafting yield by “ion pair effect”.     

The effect of monomer molecular weight of acrylate on radiation grafting of polyethylene

A series of condensed ethylene glycol acrylate monomers with differentmolecular weight was grafted to polyethylene films by means of pre-irradiation.The effect of the molecular weight of monomer and co-solvent system on thegrafting reaction and the properties of the grafted sample were studied. Theexperimental results showed that the initial rate of grafting reaction decreasedand the molar degrees of grafting linearly decreased with the increment ofmolecular weight of the monomer. The grafting degree was increased with theswelling degree of the grafted film. The biocompatibility and blood compatibilityof the grafted PE films were evaluated by the determination of hydrophilicityand anti-thrombus.     

LLDPE/SMA共混膜表面接枝PEG的研究

聚乙烯综合性能优良且价格低廉,但由于较低的表面能和惰性化学结构,其着色性、生物相容性及制品表面涂饰性能差,与各种涂饰剂的粘结强度很低,限制了其用途的拓展,须进行表面改性.聚乙烯制品的表面改性方法已有不少研究报道[1~4],相对而言,采用添加表面改性剂的方法在工艺上仍最