高频脉冲电铸Ni-Co纳米复合块体微观结构分析

采用高频脉冲电铸工艺制备出了镍钴纳米复合块体材料，利用场发射扫描电镜、能谱和X射线衍射的方法，重点研究了复合块体沉积层的表面形貌、相结构和结晶取向。结果表明．高频率和润湿剂的添加对沉积层的细化有重要影响，高频脉冲电铸能够获得微观组织致密、均匀的复合块体材料。     

助催化剂对TiCl_4/MgCl_2催化丙烯高温聚合的影响

研究了助催化剂种类(三甲基铝、三异丁基铝、三正己基铝、三乙基铝和甲基铝氧烷)及其含量对无内、外给电子体的TiCl4/MgCl2催化剂催化丙烯高温(100℃)聚合性能的影响,并用结晶分级分析、示差扫描量热和凝胶渗透色谱等方法分析了所得聚丙烯的结晶熔融行为和微观结构。实验结果表明,聚合温度从70℃升至100℃时,TiCl4/MgCl2催化剂的定向能力基本不变;100℃聚合时,以烷基化能力较弱的三异丁基铝为助催化剂时TiCl4/MgCl2催化剂的活性最高,而采用烷基化能力最强的三甲基铝为助催化剂时TiCl4/MgCl2催化剂的活性最低;100℃聚合时,助催化剂的种类对TiCl4/MgCl2催化剂的定向能力影响很小。     

负载化非茂单活性中心催化剂乙烯聚合的研究

在硅胶上负载了双(N-环己基-3-叔丁基水杨醛亚胺基)二氯化锆配合物,得到负载化非茂单活性中心催化剂。该催化剂用于乙烯聚合,考察了配合物用量、共聚单体1-己烯用量、聚合温度、聚合压力、聚合时间、三乙基铝用量对乙烯聚合性能的影响及对聚合物的相对分子质量、相对分子质量分布、熔体流动指数和密度的影响。实验结果表明,负载化非茂单活性中心催化剂保持了原均相催化剂的乙烯聚合性能;该催化剂在淤浆聚合工艺中聚合平稳,所得聚合物的颗粒形态良好。     

Diffusion-controlled size-selective chloride ion sensing in the presence of bromide ion using a thin, nanoporous, plasma-polymerized coating on an Ag/AgCl electrode

We have developed a diffusion-controlled size-selective method for sensing chloride ion in the presence of bromide ion, based on a thin, nanoporous, plasma-polymerized coating of hexamethyldisiloxane on an Ag/AgCl electrode. Sub-nanometer-sized pores responsible for a highly cross-linked polymer network in the plasma-polymerized coating allowed diffusion-controlled permeation of chloride ion while blocking the larger bromide ion. An electrode coating of thickness greater than 70 nm enabled chloride detection in the concentration range 1-10 mM in the presence of 0.63 mM bromide ion. Advantages of this approach are: (1) simple design compared with ionophore-based strategies and (2) compatibility with microfabrication and mass production processes.     

Crystalline Behavior and Magnetic Properties of Nd60Fe30-x Al10Cox（x = 0,5,10） Bulk Amorphous Alloys

Crystalline behavior and magnetic properties of Nd60Fe30-xAl10Cox( x = 0, 5, 10) bulk amorphous alloys were investigated by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and the vibrating sample magnetometer (VSM). Neither glass transition nor supercooled liquid region before crystallization was observed for the as-cast Nd60Fe30-xAl10Cox ( x = 0,5,10) bulk amorphous alloys. The glass forming ability can be improved significantly by the addition of Co. The as-cast Nd60Fe30-xAl10Cox (x = 0,5,10) alloys show hard magnetic behavior. With the addition of Co content, intrinsic coercivity (iHc) increases while the saturation magnetization(σs) and remanence (σr) decrease. The Curie temperature for the as-cast Nd60Fe30-xAl10Cox alloys increases from 451 K for x =0 to 468 K for x = 10. Some pre-cipitation of crystalline phases does not affect the hard magnetic properties of Nd60Fe30-xAl10Cox(x = 0,5,10) alloys, while the hard magnetic behavior disappears quickly after the alloys being completely crystallized.     

Effect of surfactants on phenol removal by the method of polymerization and precipitation catalysed by Coprinus cinereus peroxidase

The removal of phenol by peroxidase‐catalysed polymerization was examined using Coprinus cinereus peroxidase in the presence of surfactants. The non‐ionic surfactants with poly(oxyethene) residues, Triton X‐100, Triton X‐405 and Tween 20, enhanced the phenol removal efficiency at a level similar to high relative molecular mass poly(ethylene glycol) (relative molecular mass 3000). Although the improvement in the removal efficiency was less than that of Triton X‐100, Span 20, sodium lauryl sulfate (SDS) and lauryl trimethylammonium bromide (DTAB) also enhanced the removal efficiency. The requirement of the enzyme for almost 100% removal of 100 mg dm^?3 phenol decreased to one‐fourth by the addition of 30 mg dm^?3 Triton X‐100. Triton X‐100, Triton X‐405, Tween 20 and DTAB could reactivate the enzyme precipitated with the phenol polymer, leading to the restarting of the phenol removal reaction. Copyright © 2003 Society of Chemical Industry     

甲基丙烯酸三氟乙酰氧乙酯的聚合

对甲基丙烯酸三氟乙酰氧乙酯(TFAOEMA)的阴离子聚合及原予转移自由基聚合进行了研究。常用的阴离于引发剂如丁基锂、1，1-二苯基已基锂等很难引发TFAOEMA的阴离子聚合，而碱性较弱的引发剂如三乙基铝却容易引发，且产率较高。以氯化亚铜、五甲基二乙基三胺、溴代丙酸乙酯为引发体系的TFAOEMA的本体原子转移自由基聚合符合活性聚合特征。但在四氢呋喃为溶剂的原子转移自由基聚合中却存在活性中心失活现象。以末端含卤素的聚甲基丙烯酸甲酯为大分子引发剂，引发TFAOEMA的原子转移自由基聚合，得到了含氟双嵌段聚合物。     

低熔融指数聚丙烯的开发生产

总结了开发生产低熔融指数聚丙烯的试验过程与结果，通过优选催化剂、优化操作过程、控制加氢量，生产出质量稳定可靠的熔融指数在0．2～0．5g/l0min之间的低熔融指数聚丙烯．     

Copolymerization of bromophenylmaleimide with ethyl or butyl methacrylate

N‐p‐Bromophenylmaleimide (BrPMI) does not polymerize in solution by conventional free radical mechanism. However, it readily polymerized in bulk when mixed with a free radical initiator and heated in a microwave oven for 7–8 min. Copolymerization of ethyl methacrylate or butyl methacrylate with BrPMI was conducted in dioxane. The copolymers were characterized by IR and ¹H NMR spectroscopy and gel permeation chromatography. The monomer reactivity ratios were calculated by a non‐linear least‐square analysis. Thermal analysis indicated a great improvement in thermal stability of the copolymers compared with the methacrylate homopolymers. BrPMI was also polymerized in bulk in the DSC pan, which allowed the calculation of the activation energy of its polymerization. Copyright © 2003 Society of Chemical Industry     

核壳乳液聚合中甲基丙烯酸用量对印花制品的影响

采用核壳乳液聚合法合成涂料印花粘合剂，考察了甲基丙烯酸(MAC)用量的改变对印花产品的牢度和色光的影响：在核中，当MAC的用量分别为0．0g，0．2g，0．4g，0．6g时，干摩牢度分别为25，2．5 ，3,0，3．5，色光由暗变亮；在壳中当MAC的用量分别为0．0g，0.2g，0．4g，0．6g时，干摩牢度分别为2.5，2．5 ，3．0，3．5，色光变亮，对得色量和鲜艳度影响不大。