Surface segregation and miscibility in blends of poly(vinylidene fluoride-co-hexafluoro-acetone) with poly(butyl acrylate)

The surface segregation in poly(butyl acrylate) (PBA)/poly(vinylidene fluoride-co-hexafluoro-acetone) [P(VDF-HFA)] blends was confirmed by X-ray photoelectron spectroscopy (XPS), and is thought to be caused because the surface tension of P(VDF-HFA) is smaller than that of PBA. The PBA/P(VDF-HFA) blends were miscible at room temperature and exhibited a lower critical solution temperature (LCST) phase behavior. Thus, it was considered that the surface segregation of the P(VDF-HFA) component in PBA/P(VDF-HFA) blends was caused by the difference in surface tension between the components. Depth profiles [In(<Ø₁ (d) -Ø^b ₁) vs. depth (d), where Ø₁ (d) and Ø^b ₁ are the volume fractions at depth d from the surface and into the bulk, respectively] for PBA/P(VDF-HFA) blends were constructed by the mean-field treatment. The ln(Ø₁(d) - Ø^b ₁) vs. d plots for the PBA/P(VDF-HFA) blends could be approximated by a straight line.     

化学法测定醋酸正丁酯含量方法的改进

本文用常温静止法替代沸水浴回流法测定醋酸正丁酯含鲢,将两种化学法测定结果与气相色谱法进行了平行对照。分析了化学方法的精密度、准确度。改进后的方法应用于生产控制过程,简化了操作,又节约水、电,降低了测定成本。     

丁辛醇装置工艺技术评价

对丁辛醇装置主要专利技术的特点作了评价和对比,分析生产基本原理以及主要工艺参数。     

乙二醇二乙氨基乙基丁基醚存在下的丁二烯负离子聚合

研究了以乙二醇二乙氨基乙基丁基醚(GABE)为调节剂,正丁基锂为引发剂的丁二烯负离子聚合的聚合动力学及聚合物的微观结构。结果表明,随着GABE用量的增加,丁二烯的聚合速率增加,聚丁二烯中1,2-结构质量分数增加,聚合温度升高,聚合速率增加,但聚丁二烯中1,2-结构质量分数有所降低。     

CTAB混合反胶团萃取工业脂肪酶

研究了CTAB与Tween、含氧有机物形成的混合反胶团对工业脂肪酶进行萃取分离的效果. 实验表明,CTAB-Tween85和CTAB-含氧有机物混合反胶团的萃取率高于单一CTAB反胶团;反萃时CTAB-含氧有机物混合反胶团的反萃率与单一CTAB反胶团的反萃率相似,CTAB-Tween60和Tween40混合反胶团的反萃效果优于单一CTAB反胶团. 通过测定反萃水相的酶活,发现CTAB-TRPO混合反胶团的效果最好,酶活回收率最高,可以达到70%.     

阻尼丁基橡胶

文中研究了丁基硫化橡胶的阻尼性能。结果表明，树脂用量、填充剂类型对丁基橡胶的阻尼性能有显著影响，采用树脂共混改性是获得宽温域高阻尼丁基橡胶的比较经济和有效的方法，添加填料可以明显改善丁基橡胶的高温阻尼性能，减少阻尼性能对温度的依赖程度。     

XPG-800型悬挂式胶片冷却机的研制

介绍最新开发的XPG-800型悬挂式胶片冷却机的设计特点、工作原理、主要技术参数、结构特征，阐述了本机组主要技术改进。     

硅丙乳液的合成及其吸水性的研究

以丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸、乙烯基三乙氧基硅烷(VTES)为原料,分别采用半连续法、种子预乳化法和后添加VTES法制得了硅丙乳液。研究了聚合工艺对硅丙乳液的吸水率、冻融稳定性、钙离子稳定性等的影响。结果表明,采用半连续法和种子预乳化法制得的硅丙乳液,冻融稳定性比较好,经过冻融循环后可以复原;采用半连续法制得的乳胶膜的吸水率随着乙烯基三乙氧基硅烷的用量的增加而降低;采用后添加VTES法制得的硅丙乳液,其吸水率则随VTES用量的增加而升高,冻融循环后发生破乳。     

花椒残渣与丙烯酸丁酯合成制备阳离子絮凝剂

用提取后的花椒残渣与丙烯酸丁酯聚合制备出阳离子絮凝剂。讨论了原料粒度、引发剂用量以及单体浓度等因素对反应的影响。通过正交试验确定了最佳合成条件为:单体浓度为1.2mol/L,阳离子浓度为0.25mol/L,引发剂的浓度为0.0035mol/L。     

Comparison between the binding of chlorpheniramine maleate to poly(sodium 4-styrenesulfonate) and the binding to other polyelectrolytes

The interactions of the antihistaminic drug chlorpheniramine maleate (CPM) with the negatively charged polyelectrolytes poly(sodium 4-styrenesulfonate) (PSS) and poly(acrylic acid) (PAA) are studied by the washing method of the diafiltration technique at conditions simulating those of the small intestine such as pH 7.5 and 0.13 M NaCl. The results are compared with those already reported involving other pharmacologically important polyelectrolytes such as alginic acid (ALG), carboxymethylcellulose (CMC), and κ- and ι-carrageenan (κ- and ι-CAR). As in the case of ALG, CMC, and CAR, interactions of CPM with PAA appear to be electrostatic and are cleaved in the presence of 0.13 M NaCl. On the contrary, apart from electrostatic interactions, additional interactions are found with PSS and residual interactions are kept in the presence of 0.13 M NaCl, a fact that may be attributed to π-π interactions and hydrophobic forces. The effect of the addition of 4 M urea, branched poly(ethyleneimine) (BPEI), and poly(vinylpyrrolidone) (PVP) is also studied. The addition of urea 4 M or 0.001 M BPEI produces a decrease on the amounts of counterions bound to PSS at infinite elution, while the addition of PVP does not produce any change on the diafiltration profiles.