Characterization of pH-sensitive Poly （ acrylic acid-co-N-vinyl-2-pyrrolidone） Hydrogels Prepared by Gamma Radiation

The pH-sensitive copolymer hydrogels were prepared with the monomers of acrylic acid and N-vinyl-2-pyrrolidone based on gamma radiation technique. The morphology of the hydrogels was monitored by using scanning electron microscope. The influence of absorbed dose, monomer compasition and concentration on the swelling ratio (SR) of the hydrogels were investigated in detail. The effect of pH and temperature of the swelling medium on the swelling behavior of the hydrogels were also examined. The results show that the SR of the copolymer hydrogels decreases with the monomer concentration and absorbed dose increasing. The copolymer hydrogels show a better pH-sensitive behavior. In alkaline solution, the SR of the hydrogels is much higher than in acid solution.     

间规聚苯乙烯的等温熔体结晶

用WAXD、FTIR和DSC方法研究了间规聚苯乙烯(S-PS)的等温熔体结晶行为。发现不同温度tc下结晶所得的s-PS均为α和β两晶型的混合物。高温下(tc＞245℃)结晶有利于β晶型的生成，相对分子质量和间规度的提高有利于形成α晶型。随tc的升高，结晶样品的熔程变窄，晶体的完善程度增加。     

Synthesis and Characterization of EO／PO Random Copolyethers

Ethylene oxide (EO) and propylene oxide (PO) random copolyethers were synthesized by the sequential addition of the mixture of ethylene oxide and propylene oxide to propylene glycol (initiator) in the presence of potassium hydroxide(KOH), and characterized with infrared spectrum (FTIR) and nuclear magnetism resonance (NMR). The effects of catalyst concentration, reaction temperature, charging rate and EO/PO mixture ratio on the polymerization reaction were investigated. It was revealed that the optimal reaction condition is the ratio of 2.5 : 1 000(KOH mass vs. product mass), at 114.6℃ and pressure below 0.4 MPa. The residual KOH was neutralized by phosphoric acid (H3PO4 ). Then the crude copolyether was refined with adsorbents, and the refined copolyether, which contains less than 0.7 μg/ml K^ , was obtained as colorless, viscous liquid.     

~(60)Coγ射线辐射制备菲涅尔透镜

采用甲基丙烯酸甲酯为主单体,丙烯酸甲酯为共聚单体,利用60Coγ射线辐射聚合技术制备菲涅尔透镜.研究了辐射剂量、辐射剂量率、交联剂和单体组成对菲涅尔透镜光学性能的影响.结果表明,采用辐射聚合方法制备菲涅尔透镜时,选择适宜的辐射剂量(35kGy)和辐射剂量率(84.40Gy/min),所制备的菲涅尔透镜具有优异的光学性能.     

锦纶66高速纺丝油剂结构与性能测试

用滴定、TG和FTIR等方法对国产、进口锦纶66高速纺丝油剂的皂化值、酸值、浊点、粘度—浓度特性、粘度—温度特性及耐热性等性能进行了对比研究。结果表明：国产油剂的酸值是0．54，皂化值是18．08；粘度随油剂浓度和温度的变化平缓；起始分解温度为378．6℃。国产GW—2000油剂能满足纺丝要求，其性能与进口AZ—60油剂相当或较优。     

尼龙1010的拉伸屈服行为

研究尼龙１０１０在不同温度和拉伸速率下的拉伸屈服行为。在同一温度下，屈服应力，细颈扩展阶段的伸长倍数，应变硬化点的应变值，应硬化程度和二次成颈的应变随拉伸速率的增加近于线性增加；     

EO/PO无规共聚醚的浊点研究

研究了无规共聚醚水溶液的浓度、无规共聚醚结构度无机电解质、酸、醇、表面活性剂对浊点的影响。结果表明所选择的电解质均能降低聚醚的浊点；酸能轻微提高聚醚的浊点；水溶性醇和非水溶性醇的影响效果不同，前者能提高聚醚的浊点，后者则使之降低；表面活性荆能提高聚醚的浊点；随着聚醚中聚氧乙烯基含量的增加，其浊点升高;相对分子质量增加，使浊点降低。这些规律对无规聚醚的研究和应用有一定的指导意义。     

拉伸对尼龙1010熔融与结晶的影响

利用ＤＳＣ法研究了拉伸对尼龙１０１０熔融与结晶的影响,结果表明,伸长倍数较低时,ＤＳＣ曲线上只有一个溶融峰;λ较高时出现双熔融峰,     

EO/PO无规共聚醚的结构与性能研究

采用连续滴加料的方法,以KOH为催化剂合成了一组相对分子质量相同而组成不同的环氧乙烷/环氧丙烷无规共聚醚,采用核磁共振、红外光谱确定其组成,并用耐热性、浊点和表面张力等性能指标分析了共聚醚的结构与性能之间的关系.结果表明:把1H-NMR和13C-NMR结合起来对共聚醚的结构进行分析,既能确定各组分的含量又能够确定共聚醚链结构的特点;随着共聚醚中环氧乙烷含量的增加其热稳定性增强,浊点升高,表面张力增大.