有机硅聚合物负载环硫乙烷铂配合物的合成与催化性能

<正> 有机硅聚合物负载硫醚与铂的配合物可作为烯烃硅氢加成的有效催化剂,但其中部分配合物的回收再用性能不太理想,合成亦比较繁琐。考虑到环硫乙烷中硫原子的未共用电子对远比一般硫醚中硫原子的未共用电子对更加暴露,有可能与过渡金属形成更稳定的配合物,从而减少催化过程中金属的流失,我们合成了气相法二氧化硅固载的聚-4-氧杂-6,7-环硫庚基硅氧烷铂配合物,研究了该配合物对烯烃硅氢加成反应的催化性能。本文报道所得到的一些结果。     

巯基-乙烯基加成反应合成含硅聚合物的研究进展

巯基-乙烯基加成反应具有清洁、高效、条件温和的特点,广泛应用于有机合成、聚合物科学和材料化学等诸多领域。国内外关于这一反应的研究已有大量文献报道,但该反应在含硅聚合物的合成与应用研究中还少有触及。本文综述了巯基一乙烯基加成反应在聚硅氮烷、聚硅碳烷、聚硅氧烷三种含硅聚合物合成中的应用,介绍了国内外的研究现状及发展趋势,并...     

N-杂环卡宾金属配合物在酮硅氢加成反应中的新进展

N-杂环卡宾是一类新型催化剂和配体, 在有机化学中得到了极大的重视. N-杂环卡宾金属配合物的研究在近几年来得到迅速的发展,总结了酮硅氢加成反应中N-杂环卡宾金属配合物催化剂的应用新进展.     

光催化硅氢加成反应研究进展

有机硅产品已成为我们生活中不可或缺的一部分.催化硅氢加成反应是制备有机硅化学品和材料的重要方法,廉价而性能优异的催化剂研制和开发受到广泛关注.目前催化硅氢加成的研究还主要集中在探索新型贵金属和非贵金属配合物的催化性能,但受贵金属高成本和非贵金属配合物较低催化活性等限制,光催化作为一种环保、安全的催化方式,光催化硅氢加成反应受到重视.介绍了近年来光催化硅氢加成反应的研究进展.     

二氧化硅-聚硅氧烷负载硫杂-15-冠-5铂、铑配合物的合成及其催化硅氧化性能

6－(ω'-十一碳烯氧甲基)-1-硫杂-4,7,1O,13-四氧杂环十五烷与三乙氧基硅烷进行硅氢加成,产物依次以气相法二氧化硅固载、氯亚铂酸钾或三氯化铑络合,合成了相应的二氧化硅-聚硅氧烷负载硫杂-15-冠-5-铂、铑配合物,并研究了它们在烯烃与三乙氧基硅烷的硅氢加成反应中的催化性能.结果表明,二者均为硅氢加成反应的高效催化剂.     

十一碳烯氧甲基苯并冠醚的合成与团载化及固载化产物的催化硅氢化性能

十一碳烯氧甲基一缩二乙二醇、二缩三乙二醇分别与１，２－β（β－羟乙氧基）苯双对甲苯磺酸酯在氢化钠存在下关环缩合，得到９－十一碳烯氧甲基－２，３－苯并１５－冠－５与９－十一碳烯氧甲基－２，３－苯并１８－冠－６．二者与三乙氧基硅烷反应产物以二氧化硅固载化，得到具有十一烯氧甲基连接基团的二氧化硅固载苯并冠醚．它们可与铂形成配合物．铂配合物对烯烃与三乙氧基硅烷的硅氢加成反应具有极好的催化效能     

氮配位过渡金属配合物在硅氢加成反应中的应用研究

氮配位过渡金属配合物在近十几年来得到迅速的发展。 通过设计不同的含氮配体与不同过渡金属进行配位形成的氮配位过渡金属配合物,在硅氢加成反应中有很大应用研究价值。本文综述了氮配位铑、铁、铼、钴、锌等过渡金属配合物在酮或者烯烃的硅氢加成反应中的新进展。二 NFDA1 唑啉及二氢吡咯等含氮配体的优化设计必将大大促进含氮铁、铼、钴配合物在酮或者亚胺的硅氢加成反应中的应用。     

聚合物分散剂对氟虫脲水悬浮剂分散稳定性的影响

通过测定药物颗粒界面Zeta电位和平均粒径, 研究了聚合物分散剂苯乙烯磺酸聚合物钠盐(GY-D08)用量、pH和盐离子对氟虫脲水悬浮剂分散稳定性的影响, 研究结果表明, 分散剂GY-D08的加入量与水悬浮剂分散效果密切相关, 制备质量分数为5%氟虫脲水悬浮剂的GY-D08最佳用量为2%, GY-D08用量过多或过少都会使分散效果下降; pH影响分散剂GY-D08在水中的电离能力, 当pH=9时, GY-D08分子完全电离, 能为颗粒提供较大的静电位阻, 水悬浮剂分散稳定性最好; Mg²⁺或Ca²⁺压缩颗粒界面的双电层, 降低Zeta电位, 使颗粒因带电量减少而聚结, 导致水悬浮剂分散稳定性变差, 且Mg²⁺或Ca²⁺浓度愈大, 其分散稳定性愈差; 当离子浓度相同时, Ca²⁺压缩双电层的能力比Mg²⁺强, 添加Ca²⁺后的水悬浮剂的分散稳定性更差.     

AB2型β-环糊精功能单体及其水溶性超支化聚合物的合成与表征

为了得到结构确定的β-环糊精大单体并用于超支化聚合,通过对β-环糊精上6位伯羟基和2位仲羟基的多步功能化改性得到了同时含有Si—H和—CH CH2基团的AB2型β-环糊精大单体,并利用硅氢加成反应一步法合成了一种新型的水溶性超支化聚合物,其具有β-环糊精空腔和超支化空穴两种疏水单元,从而可构建出一种新颖的超分子体系.采用1H-NMR、13C-NMR、飞行时间质谱和元素分析对AB2单体及其聚合物的结构进行了表征.结果表明,单体和聚合物的结构与所设计的分子结构相符合.凝胶渗透色谱/多角度激光光散射(SEC/MALLS)联用仪测得该聚合物的数均分子量、分子量分布及特性黏数分别为36690、1.887和15.8mL/g.     

甲基丙烯酸酯-含氢聚硅氧烷接枝物的合成与表征

Poly(methylhydrosiloxane) was modified with methylmethacrylate by the hydrosilylation reaction, using Pt as the catalyst. The reaction was operated at the high temperature( about 140℃ ).     

Hydrosilylation of allyl carbamates by poly(methylhydrosiloxane) and related side-reactions

Hydrosilylation of allyl carbamates by poly(methylhydrosiloxane) (PMHS) catalyzed by platinum- or rhodium-based complexes was investigated. About 10% of the carbamate molecules decompose during the hydrosilylation reaction through the cleavage of the carbamate bond. A redistribution process also takes place among the polysiloxane chains resulting in the formation of branched polymers but no crosslinking occurs. A mechanism for this side-reaction is proposed. © 1993 John Wiley & Sons, Inc.     

季铵化聚酰胺胺树状聚合物封装的RuRh双金属DENs催化聚(甲基氢硅氧烷)区域选择性改性研究

采用共络合法制备了部分季铵化的第五代聚酰胺胺树状聚合物封装的RuRh双金属纳米粒子(DENs)催化剂, 分别利用紫外-可见光谱、光散射分析和透射电镜表征了该树状聚合物封装的RuRh双金属纳米粒子的形成、粒径及其分布. 红外光谱和核磁共振谱分析表明, RuRh双金属DENs催化剂对聚(甲基氢硅氧烷)的硅氢化改性显示了较高的催化活性和良好的区域选择性.     

Synthesis of poly(phosphonosiloxane) and its cyclic monomer via hydrosilylation and phosphonylation of vinylbenzyl chloride

Phosphonylation of polysiloxane and cyclosiloxane oligomers is described. Hydrosilylation of vinylbenzyl chloride (VBC) with a poly(methylhydrosiloxane), or its cyclic monomer, followed by phosphonylation with triethyl phosphite leads to the production of stable phosphonosiloxanes that are characterized by  Si C and  C P bonds. The polymer, which is a liquid with a glass transition temperature of −38.3 °C, is soluble in alcohols and an alcohol and water mixture. The phosphonylated siloxanes dissolve and chelate uranyl nitrate and transition metal salts. The hydrosilylation of VBC yields α and β isomers:  Si CH₂ CH₂ and  Si CH(CH₃); the ratio between these two depends upon the type of solvent and the reaction conversion. A kinetic study of the hydrosilylation reaction of VBC suggests a second order in respect to the reactants. The reaction rate is dependent upon the catalyst concentration and temperature. Hydrosilylation of vinylbenzyl phosphonate could not be accomplished with the platinum (complex) catalyst; this is attributed to the presence of phosphoryl groups that are strong electron donors. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4043–4053, 1999     

聚丁二酸乙二醇酯的合成

以十氢萘为溶剂,丁二酸和乙二醇直接聚合,合成了高相对分子质量的聚丁二酸乙二醇酯(PES),其结构经1H NMR和IR表征。考察了单体比例对聚合反应的影响,结果表明,当n(乙二醇)∶n(丁二酸)=1.01∶1.00时,合成的PES数均相对分子质量最高(48 640),产率93%。同时测定了PES的力学性能和热性能。     

新型结构聚芳亚胺的合成与热性能分析

通过傅-克酰化反应得到1,4-双（4′-溴苯酰基）苯,以1,4-双（4′-溴苯酰基）苯和α,α′-双（4′-氨基苯基）-1,4-二异丙基苯为单体,通过钯催化的胺基化反应缩聚合成了含异丙基的聚亚胺酮（pr-PIK）.再以pr-PIK和苯基锂为底物,通过亲核加成反应得到新型结构聚合物——含异丙基的聚醇胺（pr-PAI）.聚合物结构通过FT-IR、1H NMR和元素分析表征,表征结果与目标产物吻合良好.pr-PIK和pr-PAI的热性能由DSC和TG测定,结果表明pr-PIK和pr-PAI具有良好的热稳定性,玻璃化温度大于150℃,热分解温度大于480℃.     

3种新型聚苯基醚喹噁啉的合成

用4,4′-二氟代二苯甲酰与双酚A的溶液缩聚制得聚醚苯偶酰(PEB),经邻苯二胺改性后,通过两步法得到聚苯基醚喹噁啉（PEQ-1）。 在PEB的改性反应中加入质量分数分别为1.0%和1.3%的3,3′,4,4′-四胺基二苯醚,可有效增加聚苯基醚喹噁啉的相对分子质量,得到PEQ-2和PEQ-3（总收率≥90%）,其质均相对分子质量分别为7.492×104和1.486×105。 并用IR、 NMR等对这些聚合物进行了表征。 该法操作简便,具有潜在的应用价值。     

Polymer-Based Superhydrophobic Coating Fabricated from Polyelectrolyte Multilayers of Poly(allylamine hydrochloride) and Poly(acrylic acid)

Superhydrophobic films mainly based on poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA) polyelectrolyte multilayer have been deposited onto cleaned glass substrate by a layer-by-layer dip coating method. 3 bilayers of the PAH and PAA was directly coated onto the substrate as an underlying layer for subsequent coating. Desired surface roughness on the polyelectrolyte bilayers was created by etching the bilayers in hydrochloric acid solution so as to create the open pore having suitable size at the surface. Then, nanoparticles such as SiO₂ and TiO₂ of various sizes were deposited onto the etched polyelectrolyte bilayers. Finally, the surfaces were further modified with semifluorinated silane followed by cross-linking at 180 °C for 2 h to obtain desirable surface morphological features. The effect of etching time and addition of nanoparticles on surface morphology was investigated using an atomic force microscope (AFM). Wetting ability of the prepared film was determined by measuring water droplet contact angle using a goniometer. Adhesion between the superhydrophobic films and the substrate was evaluated by using a standard tape test method (D3359). The adhesion was improved by reducing the organic content in the films.     

聚酯酰胺的合成

聚（酯酰胺）（PEA）的主链中同时具有酯键和酰胺键,兼具了聚酯（polyester）的生物降解性和相容性以及聚酰胺（polyamide）优异的机械性能,在药物控释、组织工程以及热塑性弹性体等领域应用广泛。缩合聚合是合成聚酯酰胺最初的方法,近年来开环聚合（ROP）成为制备聚酯酰胺的主要策略,本文从环状单体均聚、环状单体共聚、环状单体和线形单体共聚等方面总结了聚酯酰胺合成的研究进展。同时,介绍了基于多组分聚合反应（MCP）的新合成方法,并对聚酯酰胺材料的发展进行了探讨和展望。     

Synthesis and Characterization of Poly(p-phenylene benzobisoxazole)/Poly(pyridobisimidazole) Block Copolymers

Poly(p-phenylene benzobisoxazole)/poly(pyridobisimidazole) block copolymers (PBO-b-PIPD) were prepared by introducing poly(pyridobisimidazole) (PIPD) moieties into the main chains of poly(p-phenylene benzobisoxazole) (PBO) in order to enhance its photostability. PBO and copolymer fibers were directly prepared from the polymerization solutions by dry-jet wet-spinning. Chemical structures and molecular chains arrangement of the block copolymers were characterized by Fourier transform infrared (FTIR) spectroscopy, solid-state ¹³C-NMR and wide angle X-ray diffraction (WAXD). Thermal stability of the copolymers was investigated by thermogravimetric analysis (TGA) in nitrogen. Thin films of PBO and copolymers were cast from methanesulfonic acid (MSA) solutions. Both the films and fibers were exposed to UV light to determine their photostability. Changes in the chemical structures and surface morphologies of the films were characterized by FTIR spectra and scanning electronic microscopy (SEM), respectively. After UV light exposure, the retention of strength for copolymer fibers is improved compared to PBO fibers. The results revealed that copolymers suffered less photodegradation in comparison with homopolymer. The mechanism for the improved photostability of the copolymers was discussed.