聚乙烯醇改性固体淀粉胶粘剂的研制

介绍新型固体淀粉胶的制备方法。以淀粉为主要原料，经加热催化分步氧化，再加入聚乙烯醇合成树脂改善其性能，然后用硬脂酸钠作为赋型剂。制得的淀粉胶剪切强度比泡花碱高0.01MPa。     

三氯氧磷交联木薯淀粉的消化性能及酶降解程度

采用In Vitro消化模型模拟人体消化道环境 ,对不同交联度 (DC)的三氯氧磷淀粉 (DC =3.70× 10 -5至 2 .2 7×10 -2 )的消化性能进行了研究 ;同时用微生素酶对三氯氧磷交联木薯淀粉进行生物降解并测定各个样品的抗酶解淀粉 (RS)含量。三氯氧磷交联变性处理对木薯淀粉的消化速度和生物降解程度的影响随交联度的不同而不同。高交联特别是使淀粉达到完全非晶化时对淀粉的消化速度和生物降解程度影响更大。     

淀粉-MMA接枝共聚物的半干法合成新工艺

以硝酸铈铵(CAN)为引发剂,采用固相半干法合成了玉米淀粉(CS)接枝甲基丙烯酸甲酯(MMA)共聚物。考察了含水量、反应体系的酸性、反应时间与温度、MMA单体和引发剂CAN用量等因素对接枝共聚反应的影响。结果表明,体系含水质量分数为35%左右,CAN用量为CS质量的1.5%～3%,反应温度在40～50℃,反应时间为0.5h左右,可得到接枝率、接枝效率和单体转化率均较高的接枝共聚物。     

多孔淀粉在内墙涂料中的应用

本用多孔淀粉和淀粉吸附天然除虫菊酯后加入内墙涂料，通过对两解吸附量、释放时间的比较，说明在内墙涂料中加入杀虫剂的可行性，同时也表明多孔淀粉作为一种新型的吸附和缓释剂，有着广泛的用途。     

Formation of hydrophilic starch coatings on polyethylene films

Thin starch coatings were deposited onto polyethylene (PE) film surfaces when PE films were immersed in 1% jet cooked starch solutions and the hot solutions were allowed to cool. Normal cornstarch, waxy cornstarch, high amylose cornstarch, and solvent‐extracted normal cornstarch (to remove native lipid) were used in these experiments. Amounts of adsorbed starch varied from about 0.03–0.05 mg per cm² of PE, and these starch coatings imparted hydrophilic properties to film surfaces, as evidenced by contact angle measurements. Although starch could be removed by gently rubbing water‐wet PE surfaces, air‐dried coatings were more firmly attached, and did not separate from the PE surface when films were bent or flexed. SEM images of starch‐coated film surfaces showed that starch was deposited as particles less than 1 μm in diameter, and also as aggregates of these submicron particles. Despite the fact that some starch samples contained only very small amounts of amylose and native lipid, surface‐deposited starch in all experiments contained 90–100% amylose; and exhibited the same V_h X‐ray diffraction pattern, indicative of helical inclusion complex formation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1781–1788, 2002; DOI 10.1002/app.10589     

Synthesis,degradation, and drug delivery of cycloaliphatic poly(ester anhydride)s

The high melting point of poly(1,4‐cyclohexanedicarboxylic anhydride) [poly(CHDA)] is a disadvantage, in that it is intractable in the melting process of a drug delivery system. This report relates to diols introduced into the polyanhydride main chain to decrease its melting point. Various poly(ester anhydride)s containing ethylene glycol, 1,3‐propanediol, 1,4‐butanediol, or 1,6‐hexandiol [poly(CHDA–XDO)] were synthesized by the esterification reaction and melt polycondensation. FTIR, DSC, WAXD, and intrinsic viscosity of polymers were recorded and hydrolytic degradation, as well as in vitro drug delivery, was conducted. The results show that the samples are stable in an anhydrous environment at room temperature and degrade in water following a surface erosion mechanism. The degradation period of poly(CHDA–XDO) ranged from 130 to 320 h as a result of the different diols and amounts of XDO introduced. The in vitro drug delivery gave 130–350 h of stable delivery along with the typical surface erosion mechanism. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2509–2514, 2002     

玉米淀粉胶粘剂的改性研究

以玉米淀粉为主要原料 ,通过预糊化、氧化、加碱糊化进行化学改性 ,并加入稳定剂可制备固含量高、贮存稳定性好 ,具有一定初粘力和透明性的改性淀粉胶粘剂。本论文主要研究了改性玉米淀粉胶粘剂的主要成分配比及工艺条件对产品性能的影响。结果表明 :淀粉氧化前是否进行预糊化处理、氧化剂的用量、体系pH值、加碱糊化时碱液用量、稳定剂的种类和用量等对改性玉米淀粉胶粘剂性能影响较大。     

高黏度苯丙乳液的制备

为了制备高性能的苯丙乳液，研究了乳化剂、助剂DZ-1及丙烯酸对苯丙乳液黏度及触变指数等性能的影响。研究结果表明：乳化剂用量低反应生成的凝聚物较多，用量大乳液的气泡较多。乳液的黏度和触变指数随DZ—1用置增大而大幅度提高。乳液黏度随丙烯酸用量的增加而提高，但用量超过3％后，耐水性能变差。乳化剂用量为1．0％，DZ-1用量为4．5％，酸用量为3．0％时合成的苯丙乳液黏度和触变指数较高。用该苯丙乳液配制的涂料黏度高、触变性好，耐擦洗及耐水性好，综合性能优良。     

Recent studies of self-condensation and co-condensation of melamine-formaldehyde resins; cure at low temperatures

Self-condensation: recent research on the chemical pathways by which alcoholated melamine-formaldehyde (MF) resins react with themselves and on the product structures is summarized. Model compound studies suggest that bridges are less stable than widely thought unless they are in hexahydro-1,3,5-triazine ring structures. In acyclic structures they are probably less stable than bridges. Co-condensation: studies of how the composition of MF resins influences the rates of reaction with poly(ol) co-reactant show that MF resins that contain very low levels of and/or functionality are quite reactive. Reactivities of a variety of poly(ester) and acrylic coreactants were studied. By combining reactive MF resins with reactive co-reactants one can formulate high solids enamels that cure by co-condensation in 30 min at 50 to 65 °C with 0.5 parts per hundred (phr) of p-toluenesulfonic acid (p-TSA) catalyst. Cure at 25 °C appears feasible with higher catalyst levels.     

A rapid test to measure performance,emission and wear of a diesel engine fueled with palm oil diesel

Results of performance, emission and tribological evaluations of palm oil methyl ester and its blends with conventional diesel in an automobile diesel engine test bed are presented. Polymerization and carbon deposits on the fuel injector were monitored. CO, CO₂, O₂, combustion efficiency and temperature of exhaust gases were also measured. Palm oil methyl ester and its blends have great potential as alternative diesel fuel. Performance and exhaust gas emission for palm oil methyl ester and its blends with conventional diesel are comparable with those of conventional diesel fuel. Palm oil methyl ester does not pose a severe environmental problem and will not deteriorate engine and bearing components.