N-异丙基丙烯酰胺对软接触镜材料性能的影响

以0.2%的2-羟基-甲基苯基丙烷-1-酮(1173)为引发剂,0.5%的二乙二醇甲基丙烯酸酯(EGDM A)为交联剂,常温下用紫外灯合成了N-异丙基丙烯酰胺(N IPAm)/甲基丙烯酸2-羟基乙酯(HEM A)/N-乙烯吡咯烷酮(NVP)三元共聚物;与相同条件下合成的HEM A/NVP共聚物进行了试验对比。凝胶在水中的溶胀实验证明,含N IPAm的三元共聚物溶胀率对温度的敏感性强于HEM A-NVP共聚物;傅立叶红外光谱与热重测试显示了两种材料的结构差异。     

Immobilization of glucoamylase on the plain and on the spacer arm‐attached poly(HEMA‐EGDMA) microspheres

Immobilization glucoamylase onto plain and a six‐carbon spacer arm (i.e., hexamethylene diamine, HMDA) attached poly(2‐hydroxyethylmethacrylate‐ethyleneglycol dimethacrylate) [poly(HEMA‐EGDMA] microspheres was studied. The microspheres were prepared by suspension polymerization and the spacer arm was attached covalently by the reaction of carbonyl groups of poly(HEMA‐EGDMA). Glucoamylase was then covalently immobilized either on the plain of microspheres via CNBr activation or on the spacer arm‐attached microspheres via CNBr activation and/or using carbodiimide (CDI) as a coupling agent. Incorporation of the spacer arm resulted an increase in the apparent activity of the immobilized enzyme with respect to enzyme immobilized on the plain of the microspheres. The activity yield of the immobilized glucoamylase on the spacer arm‐attached poly(HEMA‐EGDMA) microspheres was 63% for CDI coupling and 82% for CNBr coupling. This was 44% for the enzyme, which was immobilized on the plain of the unmodified poly(HEMA‐EGDMA) microspheres via CNBr coupling. The K_m values for the immobilized glucoamylase preparations (on the spacer arm‐attached microspheres) via CDI coupling 0.9% dextrin (w/v) and CNBr coupling 0.6% dextrin (w/v) were higher than that of the free enzyme 0.2% dextrin (w/v).The temperature profiles were broader for both immobilized preparations than that of the free enzyme. The operational inactivation rate constants (k_iop) of immobilized enzymes were found to be 1.42 × 10^?5 min^?1 for CNBr coupled and 3.23 × 10^?5 min^?1 for CDI coupled glucoamylase. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2702–2710, 2001     

The effect of polymerisation methods on the adsorption capacity of HEMA based molecularly imprinted polymers

Molecularly imprinted polymers (MIPs) are generally synthesised either by thermal initiation or by photo polymerisation methods. Recently we used a gamma irradiation method for the preparation of MIPs. In this communication we compare three different methods for the synthesis of 2-hydroxy ethyl methacrylate (HEMA) based MIP imprinted for hydrocortisone in terms of its capacity to adsorb the print molecule. Our results show that MIP prepared by the gamma irradiation method has a better adsorption capacity than the thermally initiated polymer. It is interesting to note that its adsorption capacity is comparable or marginally better than the photo polymerised MIP.     

羟基驱使苯丙聚合物/SiO_2杂化乳液的合成与成膜

制备了贮存稳定、高无机硅含量（≥21.0%）的聚（苯乙烯-丙烯酸酯）/SiO2杂化乳液（PSE/Si）,考察了甲基丙烯酸羟乙酯（HEMA）含量对杂化乳液微观形态的影响,探讨了成膜过程中Si-O-Si键的形成机理。结果发现,PSE/Si杂化乳液的粒径及其分布系数随着HEMA含量的增加而减小;透射电镜分析显示,m（HEMA...     

等离子改性条件对PEGDA/HEMA凝胶亲水性及表面能的影响

采用氩等离子对聚乙二醇双丙烯酸酯(PEGDA)/甲基丙烯酸-2-羟基乙酯(HEMA)共聚物凝胶进行表面改性,对膜材料进行了光电子能谱(XPS)分析,并讨论了等离子处理时间及功率对凝胶亲水性及表面能的影响。研究结果表明,经等离子处理后凝胶表面引入了含氧极性基团,氧的含量从未处理的23%增加到26%,使材料亲水性得到改善;由于引入极性基团,材料的表面能随等离子处理时间和功率的增加而增加,从未处理前的45.9 mJ/m2增加到72.5 mJ/m2,极性力分量γPs随等离子体处理功率和时间的变化规律与表面能γs基本一致。     

蚕丝的HEMA接枝增重和染色

选用甲基丙烯酸羟乙酯(HEMA)作为真丝接枝增重单体，探讨了影响增重率的各种因素，得出了接枝增重的最佳工艺；并研究了接枝对真丝染色性能的影响，采用活性染料和酸性染料对真丝纱线进行了先增重后染色、先染色后增重以及增重染色一浴法3种工艺的探索。     

复合水凝胶角膜接触镜材料的设计与合成

通过高聚物分子设计的方法,以吸水倍率低的HEMA水凝胶为基体材料,以吸水倍率高的PVPP(交联NVP)颗粒为分散相,制备出了具有明显相界面层的复合水凝胶角膜接触镜材料.通过大量实验表明其制备工艺为:PVPP颗粒与单体HEMA的质量比为10:90,致孔剂PEG400为35%(wt,相对于总反应物),BPO为0.4%(wt,相对于反应单体),反应混合物混合均匀后立即压片、放入温度为75℃的水浴中,反应12h.为下一步研究具有药物缓释功能的、可重复利用的角膜接触镜奠定了基础.     

A poly(2-hydroxyethyl methacrylate)-based immobilized metal affinity chromatography adsorbent for protein purification

Poly(HEMA) microbeads were prepared by suspension polymerization of 2-hydorxyethylmethacrylate and ethyleneglycoldimethacrylate (EGDMA). The water content, ligand density, and selectivity for poly(His)-tagged d-hydantoinase of the poly(HEMA)-based adsorbents were affected by the concentration of EDGMA used during polymerization. The Ni(II)-loaded poly(HEMA) adsorbent exhibited an adsorption capacity of 1.0 mg/g for poly(His)-tagged d-hydantoinase under optimal conditions with buffer containing 100-300 mM NaCl at pH 6.0. One-step purification protocol with the adsorbent gave a purity of at least 92%. The adsorption capacity of adsorbent declined by 54% after 7 cycles, due to the leaching of Ni(II) from the adsorbent. However, upon regeneration the adsorption capacity can be restored. Given the ease of preparation and the chemical and microbial resistance, the poly(HEMA)-based IMAC adsorbent could be a promising substitute for the polysaccharide-based IMAC adsorbents.     

HEMA-NVP共聚物表面性能研究

室温下,以质量分数为0.2%的2-羟基-甲基苯基丙烷-1-酮(1173)为引发剂,0.5%的二乙二醇甲基丙烯酸酯(EGDMA)为交联剂,在紫外光照下合成了甲基丙烯酸2-羟基乙酯(HEMA)-N-乙烯吡咯烷酮(NVP)二元共聚物水凝胶.探讨了共聚物表面的润湿性、脱水性及对牛血清蛋白(BSA)的吸附性.试验表明,材料薄膜表面接触角随着NVP含量增大及接触时间的延长而减小;BSA通过物理作用吸附于水凝胶薄膜表面,BSA吸附量随时间延长及吸附液初始浓度升高而增大;随着共聚物中NVP含量的增大,BSA吸附量增大,而释放量减小;脱水试验表明水凝胶薄膜的脱水速率随NVP及交联剂含量的增大而减小.     

Synthesis of a new photoreactive gelatin with BTDA and HEMA derivatives

A novel bio-affinitive, photocuring, and membrane-forming gelatin derivative was synthesized in this study. This process was based on the amide formation between carboxylic acid and the amine in methanol–water media using dicyclohexyl-carbodiimide (DCC) as a condenser. Gelatin and glycine were the sources of amine in the model reaction. Since there were two anhydride groups in each 3,3′,4,4′-benzophenone tetra-carboxylic dianhydride (BTDA) molecule, two 2-hydroxyethyl methacrylate (HEMA) molecules were used to induce the ring-opening reaction of BTDA and release two carboxylic acid groups. The resulting photoreactive gelatin was called GE-BTHE, of which the photoreactive component was the ketone groups of BTDA and HEMA that played the role of double bond supplier. This photoreactive gelatin could be converted from the transparent liquid phase into swollen membrane by a 6-min irradiation of high pressure mercury lamp. The most efficient irradiation was at 267 nm and the highest degree of swelling of the cured GE-BTHE membrane could reach 5.9. The elongation from the dried gel remained 5–10%, i.e., relatively elastic. The properties of this gelatin derivative were investigated using amide formation analysis, calculation of the gel content and the swelling ratio, and monitoring of the photocuring process. The GE-BTHE synthesized in this study should be very potential in applications such as protective wound dressings and hemostatic absorbents for minimally invasive surgery. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008