TiSiW12O40/TiO2催化合成丙酸正丙酯

研究了固载杂多酸盐TiSiW12O40/TiO2催化丙酸与正丙醇的酯化反应，探讨了催化剂用量，反应时间及醇酸摩尔比对酯收率的影响。当醇酸摩尔比为1.3:1，催化剂的量为醇酸总质量的1.5%。反应时间为1.0h，酯产率可达71.4%以上，采用该催化剂合成丙酸正丙酯不仅酯化反应温度低，反应时间较短，催化剂用量少，而且可较好地回收利用，可降低成本；因此，TiSiW12O40/TiO2是合成丙酸正丙酯的优良催化剂，具有良好的应用前景。     

3,4,5-三羟基苯甲酸丙酯的合成

3，4，5-三羟基苯甲酸丙酯，俗名称没食子酸丙酯，本文以固体超强酸SO4^2-／TiO2为催化剂合成没食子酸丙酯，研究了催化剂在没食子酸与正丙醇反应中的催化活性，考察了焙烧温度对催化剂性能的影响以及酸醇物质的量比对酯收率的影响。实验结果表明：焙烧温度在500℃的条件下，制得的催化剂活性最高；没食子酸：正丙醇的物质的量比为1：15，1．8g固体超强酸SO4^2-／TiO2，在120℃下，反应时间2．5h。收率达96．3％。     

甲基丙烯酰胺丙基二甲基胺的合成与应用述评

介绍了甲基丙烯酰胺丙基二甲基胺（DMAPMA）的合成工艺路线,重点阐述了该产品在水处理行业、日化行业、造纸加工业、医药行业等中的实际应用.     

Ionic liquids as electrolytes

Salts having a low melting point are liquid at room temperature, or even below, and form a new class of liquids usually called room temperature ionic liquids (RTIL). Information about RTILs can be found in the literature with such key words as: room temperature molten salt, low-temperature molten salt, ambient-temperature molten salt, liquid organic salt or simply ionic liquid. Their physicochemical properties are the same as high temperature ionic liquids, but the practical aspects of their maintenance or handling are different enough to merit a distinction. The class of ionic liquids, based on tetraalkylammonium cation and chloroaluminate anion, has been extensively studied since late 1970s of the XX century, following the works of Osteryoung. Systematic research on the application of chloroaluminate ionic liquids as solvents was performed in 1980s. However, ionic liquids based on aluminium halides are moisture sensitive. During the last decade an increasing number of new ionic liquids have been prepared and used as solvents. The general aim of this paper was to review the physical and chemical properties of RTILs from the point of view of their possible application as electrolytes in electrochemical processes and devices. The following points are discussed: melting and freezing, conductivity, viscosity, temperature dependence of conductivity, transport and transference numbers, electrochemical stability, possible application in aluminium electroplating, lithium batteries and in electrochemical capacitors.     

气相酯交换法合成碳酸甲丙酯负载型催化剂的研究

考察了负载型金属氧化物催化剂对碳酸二甲酯和丙醇气相酯交换合成碳酸甲丙酯的催化性能,并采用BET、XRD、CO2-TPD方法对催化剂进行了表征.结果表明,TiO2/Al2O3对反应具有较高的催化活性和稳定性.随着TiO2负载量的增加,催化剂的比表面积减小,而催化性能则随Ti负载量的增加先增加后减小,在Ti负载量为5%(wt)时活性达到最高,当Ti负载量低于5%(wt)时,TiO2可能以非晶态形式分散在Al2O3表面,而当Ti负载量高于5%(wt)时,TiO2以微晶的形式存在.CO2-TPD研究表明,负载量的改变对催化剂的碱性影响不明显.     

乙酸乙酯与乙酸正丙酯的切换式连续生产

作者在对乙酸乙酯、乙酸异丙酯、乙酸正丙酯和乙酸丁酯的现有生产工艺进行分析后,以乙酸乙酯和乙酸正丙酯为研究对象,在以往对两者研究的基础上,提出了乙酸乙酯与乙酸正丙酯切换式连续生产的工艺流程,并且通过模拟计算和小试验证证明,在同样的生产装置上,可以分别连续生产乙酸乙酯和乙酸正丙酯,采用该工艺生产乙酸乙酯能耗低于传统工艺12%,生产乙酸正丙酯比原有工艺可以提高收率2%。     

Formulation and development of ophthalmic in situ gel for the treatment ocular inflammation and infection using application of quality by design concept

Context: The conventional liquid ophthalmic delivery systems exhibit short pre-corneal residence time and the relative impermeability to the cornea which leads to poor ocular bioavailability.

Objective: The aim of this study was to apply quality by design (QbD) for development of dexamethasone sodium phosphate (DSP) and tobramycin sulfate (TS)-loaded thermoresponsive ophthalmic in situ gel containing Poloxamer 407 and hydroxyl propyl methyl cellulose (HPMC) K4M for prolonging the pre-corneal residence time, ocular bioavability and decreases the frequency of administration of dosage form. The material attributes and the critical quality attributes (CQA) of the in situ gel were identified. Central composite design (CCD) was adopted to optimize the formulation.

Materials and methods: The ophthalmic in situ forming gels were prepared by cold method. Materials attributes were the amount of Poloxamer 407 and HPMC and CQA identified were Gel strength, mucoadhesive index, gelation temperature and % of drug release of both drug.

Results and discussion: Optimized batch (F*) containing 16.75% poloxamer 407 and 0.54% HPMC K4M were exhibited all results in acceptable limits. Compared with the marketed formulation, optimized in situ gel showed delayed T_max, improved C_max and AUC in rabbit aqueous humor, suggesting the sustained drug release and better corneal penetration and absorption.

Conclusion: According to the study, it could be concluded that DSP and TS would be successfully formulated as in situ gelling mucoadhesive system for the treatment of steroid responsive eye infections with the properties of sustained drug release, prolonged ocular retention and improved corneal penetration.     

可聚合甲基丙烯酰氧丙基磷酸酯的合成

以三氯氧磷、三乙胺、丙烯酸羟丙酯(HPA)等为原料,通过多步法合成了一种磷酸酯反应型乳化剂。实验对原料配比、反应时间、反应温度等进行讨论,得到最佳工艺条件,并用红外光谱对产品进行结构表征。结果表明,合成甲基丙烯酰氧丙基磷酸酯中间体,选择n(三氯氧磷)∶n(三乙胺)∶n(HPA)=1.1∶1.3∶1,反应时间为1.5h,反应温度为25℃,第二步水解反应温度0~15℃,水解物料比为n(中间体产物)∶n(三乙胺)∶n(水)=1∶1.4∶1.2时,最终产物收率最高,可达98.80%。     

甲基丙烯酰胺丙基二甲基胺的合成

以甲基丙烯酸甲酯和N,N-二甲基丙二胺为原料,二丁基二月桂酸锡为催化剂,对苯二酚为阻聚剂合成了甲基丙烯酰胺丙基二甲基胺(DMAPMA)。确定了合成的最佳工艺为:n(甲基丙烯酸甲酯)∶n(N,N-二甲基丙二胺)=3∶1,催化剂用量为反应液总质量的2.0%,阻聚剂用量为反应液总质量的0.1%,反应温度为体系回流温度,反应时间为3h,在此条件下,产率达96%以上,二丁基二月桂酸锡可重复使用。     

甲基丙烯酸-3-三甲氧基硅丙酯的水解-缩合反应速率常数

在甲基丙烯酸-3-三甲氧基硅丙酯（MPS）和苯乙烯的乳液共聚合反应中,MPS与水接触时其SiOR基团会发生水解缩合反应,其反应速率对乳液体系的稳定有很大的影响,而且所得产物的杂化结构也由SiOR基团的水解缩合反应速率决定.通过²⁹Si核磁共振谱,测定了不同pH值下MPS的水解-缩合速率常数.发现MPS的水解速率常数在pH=7时最小,无论是在酸性条件还是碱性条件都使其迅速增大.而MPS的缩合速率常数则在pH=4时达到最小,而在相对较高pH值和更低的pH值时,其缩合速率常数也都迅速增大.并得到了不同pH值时水解-缩合速率常数估算式.为进一步研究MPS乳液聚合的过程机理、反应过程动力学模型的求解以及通过模型对反应结果的预测提供了依据和基础数据.