MDC分解法制备MDI的研究进展

综述了MDC（二苯基甲烷二氨基甲酸甲酯）分解法制备MDI（二苯基甲烷二异氰酸酯）的机理、分类、反应条件及国内外有关研究进展;以烷类或酯类作溶剂,锌或锌的氧化物作催化剂的工艺会逐渐成熟;开发性能优良、价格便宜、工业应用前景良好的催化剂体系,实现装置的连续化生产和采用恰当的反应工艺以利于实际工业生产是未来的研究方向。     

表面活性冠醚

综述了表面活性冠醚的结构、合成方法及其在水溶液中的性质。对其在相转移催化、离子选择电极及模拟膜中的应用也进行了简略的讨论。     

氮杂冠醚合成中的双功能基试剂

综述了氮杂冠醚合成中的双功能基试剂的进展。着重讨论了典型的双功能基试剂,如取代多甘醇、二胺、氨基二醇、二卤代物、二醛和二酮以及3-烷氧丙烯醛等的制备方法。     

Levels of polybrominated diphenyl ethers in house dust in Central Poland

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products, from which they are emitted to the environment, including house dust. House dust is a source of human exposure to these compounds by ingestion. The aim of this article was to determine the levels of selected PBDEs in the house dust and indicate their potential sources of origin. PBDE congeners: BDE‐47, BDE‐99, BDE‐153 and BDE‐209, were analyzed in 129 samples. The geometric mean levels (and 95% CIs) of the aforementioned congeners amounted to 3.8 (3.1–4.7) ng/g, 4.5 (3.5–5.6) ng/g, 2.2 (2.1–2.4) ng/g and 345 (269–442) ng/g respectively. BDE‐209 was the dominant congener in the majority of tested samples. We found a statistically significant correlation between the concentrations of BDE‐47 and the computer operating time per day (r_s – 0.18) and the living area (r_s – 0.20). Statistically significant higher levels of BDE‐99 were found in homes where the floor was not replaced during the last 2 years.     

4,4′-二氨基二苯醚的快速分析法

在生产工艺稳定的条件下聚酰亚胺薄膜的性能与原材料的质量密切相关。4，4′－二氨基二苯醚是生产均苯型聚酰亚胺的主要原材料之一，论文介绍了一种对其纯度进行快速、简便测定的方法。该方法的准确性、重复性都较好。     

杯芳冠醚合成方法的改进

采用合理分步式减压蒸馏,尽可能消除五甘醇减压蒸馏过程中的KCI后,用“一锅煮”的方法合成了两种1,3-交替构象的杯[4]芳烃-冠-6衍生物,并通过了熔点、质谱、^1H NMR、^13C NMR确证。结果表明,改进后的方法有可能推广到多种杯芳冠醚的合成中。     

Evaluation of Some Starch Derivatives Containing Amide Groups as Flocculants

Three types of starch derivatives namely poly(acrylamide)‐starch graft copolymer, carbamoylethylated starch, and starch carbamate were prepared and evaluated as flocculants. Native and hydrolyzed maize starches were used as parent materials for these derivatives. The flocculation was followed by monitoring transmission % and weight removal %. The different factors affecting flocculation were studied. These factors include: (a) flocculant dose, (b) pH of the flocculation medium and (c) starch derivatives type, molar mass and nitrogen content. The flocculation efficiency of the three starch derivatives follows the order: poIy(acryIamide)‐starch graft copoIymer > carbamoylethylated starch > starch carbamate. The flocculation efficiency increases on increasing the nitrogen content and/or decreasing the molar mass of the flocculant. The flocculation efficiency of various flocculants at pH 6 is higher than at pH 8. The poIy(acryIamide)‐ starch graft copoIymer based on H₃‐starch has a higher flocculation efficiency than polyacryIamide.     

4,4’-二氨基二苯砜固化环氧树脂/蒙脱土纳米复合材料反应动力学的研究

选择4,4’-二氨基二苯砜（DDS）作为固化剂,采用非等温DSC法研究了双酚A缩水甘油醚型环氧树脂（E-51）/有机蒙脱土（MMT）纳米复合材料的固化反应动力学,根据Kissinger方程计算出该反应的表观活化能（ΔE）为59.91 kJ/mol,基于Crane方程计算得到该反应的反应级数为0.89,表明该反应为一复杂反应,根据固化反应动力学测试结果确定了E-51/DDS/MMT体系固化成型工艺.     

羟基多溴二苯醚生物活性的QSAR研究

采用VSMP方法从大量的分子结构描述符中筛选最优子集,用多元线性回归方法分别构建了羟基多溴二苯醚（hydroxylated polybrominated diphenyl ethers,OH-PBDEs）对细胞色素CYP19介导类固醇生成的抑制活性,甲状腺受体-β（thyroid receptors,TR-β）的激素活性以及与甲状腺素结合球蛋白（thyrox-ine-binding globulin,TBG）和甲状腺转运蛋白（transthyretin,TTR）之间结合能力的定量构效关系（quantita-tive structure-activity relationship,QSAR）模型。模型的留一法交叉验证（leave-one-out cross validation,LOO-CV）相关系数Q2和拟合相关系数R2均高于0.95和0.97,表明模型具有良好的稳健性、拟合能力和预测能力。QSAR模型表明OH-PBDEs的分子三维结构和芳香性是其活性的重要影响因素。另外,分子中溴原子数量和取代位置对OH-PBDE生物活性具有重要影响。