检索结果-南通市图书馆

酶促开环聚合与自缩合乙烯基共聚合相结合制取超支化聚合物

在线全文

学校读者我要写书评

暂无评论

高等学校化学学报 2007年第4期28卷 798-800页

作者：刘啸天李亚鹏王书唯沙柯王薇陈亮王静媛吉林大学化学学院麦克德尔米德实验室长春130012 吉林大学第一医院长春130023

This work was directed to develop a novel method for the synthesis of hyperbranched polymers by combining enzymatic ring-opening polymerization(ROP) with self-condensing vinyl copolymerization(SCVCP). Functionalized PCL was prepared by ROP of ε-CL with HEMA as the initiator and catalyzed by novozyme 435, and subsequently converted to AB* macroinimer by the esterification with 2-bromoisobutyryl bromide. The target polymer was obtained by SCVCP of AB* macroinimer with styrene via ATRP.

关键词：酶促开环聚合 novozyme 435 自缩合乙烯基共聚合超支化聚合物

Optimization and kinetic modeling of lipase mediated enantioselective kinetic resolution of (±)-2-octanol

在线全文

学校读者我要写书评

暂无评论

Natural Science 2013年第9期5卷 1025-1033页

作者： Jyoti B. Sontakke Ganapati D. Yadav Department of Chemical Engineering Institute of Chemical Technology Mumbai India

Chiral 2-octanol is one of the key intermediates for preparation of liquid crystal materials, as well as many optically active pharmaceuticals. Lipase catalyzed kinetic resolution has proved to be an efficient technique for synthesis of enantiomerically enriched compounds. In the present study, optimization and kinetic modeling of kinetic resolution of (±)-2-octanol was done by using vinyl acetate as an acyl donor in n-heptane as a solvent. Response surface methodology (RSM) and four-factor-five-level Centre Composite Rotatable Design (CCRD) were employed to evaluate the effect of various parameters such as speed of agitation, enzyme loading, temperature and acyl donor/alcohol molar ratio on conversion, enantiomeric excess (ee), enantioselectivity and initial rate of reaction. Acylation of 2-octanol with vinyl acetate catalyzed by novozyme 435 follows the ternary complex mechanism (ordered bi-bi mechanism) with inhibition by 2-octanol.

关键词： Immobilized Lipase novozyme 435 2-Octanol Response Surface Methodology Kinetic Modeling Enantioselectivity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

响应面法优化脂肪酶催化脂肪酸甲酯环氧化

中国油脂 2013年第7期38卷 64-68页

作者：宋亚玲李立琴冯树波赵亚男冯丹华河北科技大学化学与制药工程学院石家庄050018 河北省药物化工工程技术研究中心石家庄050018 石家庄合佳保健品有限公司石家庄050000

以novozyme 435脂肪酶为催化剂,在单因素实验的基础上,利用响应面法优化了脂肪酸甲酯(FAMEs)环氧化工艺。选择反应时间、脂肪酶用量和H2O2与FAMEs双键的摩尔比为自变量,环氧值为响应值,建立了脂肪酶催化FAMEs环氧化体系的二次回归模型... 详细信息

以novozyme 435脂肪酶为催化剂,在单因素实验的基础上,利用响应面法优化了脂肪酸甲酯(FAMEs)环氧化工艺。选择反应时间、脂肪酶用量和H2O2与FAMEs双键的摩尔比为自变量,环氧值为响应值,建立了脂肪酶催化FAMEs环氧化体系的二次回归模型。优化后的工艺条件为:在不加脂肪酸氧载体的条件下,FAMEs 20 g,甲苯用量30 mL,脂肪酶用量3%(以FAMEs质量计),H2O2与FAMEs双键摩尔比1.7∶1,反应温度40℃,反应时间5 h。在此条件下,环氧值为4.82%,与模型预测值基本一致。

关键词： novozyme 435脂肪酶脂肪酸甲酯环氧化响应面法

在线全文

学校读者我要写书评

暂无评论

酶法醇解油茶籽油的研究

中国油脂 2012年第5期37卷 35-38页

作者：刘丽萍王卫飞王永华杨博宁正祥华南理工大学轻工与食品学院广州510640 华南理工大学生物科学与工程学院广州510006

在有机溶剂体系中,以油茶籽油和异丙醇为底物,通过脂肪酶催化醇解反应进行油茶籽油改性合成富含油酸的甘油二酯、甘油单酯、异丙酯。考察了溶剂种类、酶种类、底物摩尔比、反应温度和酶加量5个因素对醇解反应的影响。结果表明,最优反应... 详细信息

在有机溶剂体系中,以油茶籽油和异丙醇为底物,通过脂肪酶催化醇解反应进行油茶籽油改性合成富含油酸的甘油二酯、甘油单酯、异丙酯。考察了溶剂种类、酶种类、底物摩尔比、反应温度和酶加量5个因素对醇解反应的影响。结果表明,最优反应条件为:以叔丁醇为溶剂,脂肪酶novozyme 435为催化剂,底物异丙醇与油茶籽油摩尔比6∶1,酶加量为底物质量的1%,反应温度55℃。在此条件下反应36 h后甘油三酯转化率达到95.24%,甘油二酯、甘油单酯、异丙酯的含量可分别达到11.58%8、.25%、75.41%。

关键词：油茶籽油异丙醇甘油二酯甘油单酯异丙酯 novozyme 435