聚酰胺-胺的合成及在水处理中的应用

聚酰胺-胺(PAMAM)树枝状大分子作为一类三维的、分子尺寸和构型高度可控的高分子聚合物,因其具有无毒高效、易于修饰等优点,已在工业水处理领域引起了广泛的关注。本文介绍了PAMAM的主要合成路线及工艺优缺点,综述了近年来PAMAM及其改性衍生物在工业水处理中应用研究进展,分析其作用机理及影响因素,最后对未来的研究方向作以展望。     

聚酰胺-胺树枝状大分子的研究进展

聚酰胺-胺（PAMAM）是一种新型树枝状大分子,其改性和应用是目前研究的热点。PAMAM已在多个领域显示出良好的应用前景。本文综述了PAMAM在生物医药、表i面活性剂、催化剂、光电材料、分子自组装、纳米材料、水处理等方面所取得的成果。     

PAMAM树状大分子负载和释放阿霉素的耗散粒子动力学模拟

采用耗散粒子动力学模拟方法研究了药物输送载体聚酰胺-胺（PAMAM）树状大分子对抗癌药物阿霉素（DOX）的负载和释放行为。构建了PAMAM树状大分子的粗粒化模型,该模型能准确地重现树状大分子的构象性质。考察了PAMAM树状大分子代数（G）对DOX负载以及pH环境对DOX释放的影响。模拟结果表明,PAMAM树状大分子主要通过疏水作用将DOX包封于内部空腔,G6和G7 PAMAM树状大分子的负载能力较强,因为其孔隙率较高,内部有更多的疏水空腔。在低pH环境下,PAMAM树状大分子结构发生变化,DOX分子能快速地从其中释放,主要原因是PAMAM的伯胺、叔胺和DOX伯胺发生质子化,质子化基团间的静电排斥作用使得PAMAM树状大分子发生溶胀,导致其内部空腔暴露,促进了DOX的释放。本工作可以为基于树状大分子的药物输送体系的设计和优化提供参考。     

PAMAM树状大分子负载和释放阿霉素的耗散粒子动力学模拟

采用耗散粒子动力学模拟方法研究了药物输送载体聚酰胺-胺(PAMAM)树状大分子对抗癌药物阿霉素(DOX)的负载和释放行为。构建了PAMAM树状大分子的粗粒化模型,该模型能准确地重现树状大分子的构象性质。考察了PAMAM树状大分子代数(G)对DOX负载以及pH环境对DOX释放的影响。模拟结果表明,PAMAM树状大分子主要通过疏水作用将DOX包封于内部空腔,G6和G7 PAMAM树状大分子的负载能力较强,因为其孔隙率较高,内部有更多的疏水空腔。在低pH环境下,PAMAM树状大分子结构发生变化,DOX分子能快速地从其中释放,主要原因是PAMAM的伯胺、叔胺和DOX伯胺发生质子化,质子化基团间的静电排斥作用使得PAMAM树状大分子发生溶胀,导致其内部空腔暴露,促进了DOX的释放。本工作可以为基于树状大分子的药物输送体系的设计和优化提供参考。     

PAMAM树状大分子在水处理中的应用研究进展

PAMAM树状大分子具有特殊结构与性能,应用于水处理中,具有无毒和高效的特点。本文综述了PAMAM树状大分子在含重金属离子废水、染料废水、高硅水等水处理中的应用研究。PAMAM树状大分子在水处理中的处理效果受溶液的pH值、作用时间、树状大分子的代数等因素的影响,且在含重金属离子废水处理中可再生。最后探讨了PAMAM树状大分子在水处理应用中存在的问题,预测未来将通过改性PAMAM树状大分子或合成新树状大分子扩大其在水处理中的应用范围。     

ASP油田污水处理用聚酰胺-胺的研究进展

对PAMAM在三元复合驱油田污水处理过程中作为絮凝剂和破乳剂的研究进行了归纳分析,主要介绍了PAMAM合成工艺、应用条件及处理效果。PAMAM树形大分子及其端基改性产物具有很好的絮凝和破乳性能,在油田水处理领域具有广泛的应用前景。     

PAMAM树枝状大分子在分离膜中的应用

PAMAM树枝状大分子具有典型的树枝状聚合物结构,其分子结构高度几何对称,分子结构可控,表面带有大量的氨基,内部含有空腔,同时表面官能团易修饰,近年来受到国内外研究者的广泛关注,在外刺激应答、纳米材料、光电器件、催化、生物等领域已经得到广泛的应用,其在分离膜领域的应用也备受关注。综述了PAMAM近年来在分离膜领域各个方向的研究进展,并对其对该领域的未来发展进行了展望。     

PAMAM接枝改性碳纤维表面及分子动力学模拟

采用化学法将聚酰胺-胺树枝状大分子(PAMAM)接枝在T700碳纤维(CFs)表面,对比了不同代数PAMAM分子接枝前后CFs表面的微观形貌,并对CFs/环氧微复合材料的界面剪切强度(IFSS)进行测试及材料拉脱断口处形貌观察。与未处理纤维相比,经过G1.0代PAMAM接枝处理后的复合材料IFSS值提高了30.37%。采用Materials Studio程序包,建立碳纤维、环氧树脂及两者间界面的结构模型并进行优化,通过分子动力学模拟并计算了界面相互作用能,结果表明,引入PAMAM分子会提高CFs与环氧树脂间的界面结合能,与实验结果一致。     

聚酰胺-胺(PAMAM)应用研究进展

PAMAM树状大分子具有特殊结构与性能,表现出一些独特的性质,因此使其成为各领域的研究热点。文章简要介绍其在化工、药物载体方面的应用研究现状。最后通过自身的研究现状对其未来的发展应用进行展望。     

树枝状高分子研究应用进展

树枝状大分子是近年来出现的一类新型合成高分子,具有高度支化、结构规整、单分散等特性。这些特点使其在许多领域有潜在的重要应用价值,成为相关领域的研究热点。本文介绍了树枝状大分子在催化剂、生物医药、表面活性剂、液晶领域的研究及应用探索进行了综述,最后对树枝状分子的未来的发展进行了展望。     

两性高分子水处理剂的研究现状与发展

本文叙述了两性高分子水处理剂在水溶液中有别于一般的阴、阳离子型水处理剂的独特性质,介绍了国内外常见的两性高分子水处理药剂,及其在水处理应用中的独特优势。预测在今后的水处理研究应用中,两性高分子水处理剂将取得突破性进展,而天然改性类两性高分子水处理剂在我国将占有较重要的地位。     

Influence of prolonging vulcanization on the structure and properties of hard rubber

This research on vulcanization illuminates the structure–property relationship of hard rubber with prolonging vulcanization. At the early stage of curing, polysulfur reacts with styrene–butadiene rubber (SBR) macromolecules to form chemical crosslink, as evidenced by the significant increase of modulus during vulcanization. The chemical crosslink is followed by a large amount of interchain attraction, which is due to the modification of SBR macromolecules by combined sulfur. The combined sulfur is formed by the reaction of sulfur atom with SBR backbone, which improves the polarity of SBR macromolecules since sulfur is polar. The influences of chemical crosslink and interchain attraction on the mechanical properties, thermal properties, dynamic mechanical properties, and fracture morphology were analyzed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Concept of quasimonomers and its application to some problems of polymer statistics

The concept of quasimonomers is introduced, i.e. the concept of disconnected quasiparticles, which can be effectively substituted for a chain of connected monomers in the analysis of volume interactions in polymeric coils. Such a substitution becomes possible because each monomer of an infinite homogeneous chain is ‘standardly surrounded’ by the other monomers (primarily by near neighbours along the chain) and solvent molecules. This ‘standard surrounding’ renormalizes the monomer characteristics in such a way that each monomer can be considered as a disconnected quasiparticle, the properties of which do not coincide with the properties of the initial monomer. The application of the concept of quasimonomers to the analysis of volume interactions in inhomogeneous macromolecules (finite linear macromolecules, macromolecules with defects and branched macromolecules) leads to results which differ from the results of classical Flory-type theories. This is connected with the fact that the interaction characteristics for these macromolecules turn out to be dependent on the positions of corresponding monomers in the chain. The following topics are considered with the help of the method of quasimonomers: the θ behaviour of finite chains, of chains with defects and of branched chains; the partial specific volume of polymeric macromolecules; and the relation between the polymer chain models. In Appendix 2 the good solvent behaviour of branched macromolecules is also discussed.     

生物质阻燃涂层在涤纶纺织品上的研究进展

涤纶纺织品易燃并伴有熔滴现象,易产生二次危害,这极大地限制了其广泛应用.因此,开发阻燃涤纶纺织品意义重大.生物质阻燃剂以其绿色环保、可持续发展等优势成为近年来阻燃剂领域的新秀,具有很好的发展前景.对国内外生物质阻燃剂在涤纶纺织品中的阻燃研究现状进行了综述,主要介绍了植酸、壳聚糖、海藻酸盐、蛋白质和其他生物质大分子在涤纶...     

Neutral and Cationic Macromolecules based on Iron Sandwich Complexes

This article is one of a number of reviews in the special issue of the Journal of Inorganic and Organometallic Polymers and Materials, celebrating the 50th anniversary of the discovery of metallocene-based polymers. Since the first examples of polyferrocenes in 1955, research into the design of organometallic polymers has grown exponentially. Organoiron polymers have incorporated ferrocene and arene cyclopentadienyl complexes, and have been developed for materials, liquid crystals, and electrocatalysts. The focus of this review is on the synthesis, properties, and characterization of macromolecules based on ferrocene or arene cyclopentadienyliron cations. Ferrocene-based polymers in which the ferrocene moieties are in or pendent to the backbone are described, as well as, the use of arene cyclopentadienyliron complexes in the design of polymeric materials. The design of star-shaped macromolecules and dendrimer materials that contain ferrocene and/or arene cyclopentadienyliron units will be discussed as well.     

蛋白质沉淀结晶研究进展

论述了国内外生物大分子 (蛋白质、酶等 )沉淀结晶的研究现状和进展 ,着重从结晶热力学、粒子聚集、结晶的成核与晶体生长 ,以及场的作用等方面阐述了蛋白质沉淀结晶过程的特定现象与可能的结晶机理 ,对蛋白质的沉淀结晶过程作了全面的描述 ,并提出未来研究方向 ,为蛋白质结构分析、新药设计、生化研究以及工业化生产提供一定的基础     

气-质联用对苯胺与丙酮缩合反应产物分析

质谱仪作为一种有效的化合物结构分析手段,在有机合成、天然产物分析及生物活性大分子结构鉴定中起着举足轻重的作用。本文利用GC—MS对苯胺与丙酮缩合反应的产物进行了结构分析。     

Radiation-induced network formation in polymers

The topological approach to radiation crosslinking of polymers is based on research of the transition from one topological form of macromolecules to another form, especially from a branched to a network form. The different types of transition and different threshold doses are considered. On the basis of the statistical physics of macromolecules, a conclusion about the network formation through cycles of definite size was made. The dependence of properties of radiation-crosslinked polymers on characteristics of topological forms was studied. The characteristics of topological forms for some polymers [poly(vinylchloride), block copolymers, and polyethylene] were determined. © 1996 John Wiley & Sons, Inc.     

The mystery of clustering in macromolecular media

Clustering occurs in most polar media such as water-soluble macromolecules. The true origin of clustering has been elusive despite a great deal of research effort. This paper uses the simplest water-soluble polymer, poly(ethylene oxide), dissolved in deuterated water to investigate the cause of clustering. The small-angle neutron scattering technique is used to separate out solvation effects from clustering effects and back out the various interaction parameters. It is found that clustering is related to attractive inter-chain interactions between hydrophobic groups which create physical crosslinks thereby causing clustering.     

Nucleation and growth of carbon black particles during thermal decomposition of benzene

The authors determined the mechanism of carbon black formation during the thermal decomposition of benzene diluted with a stream of nitrogen. The kinetics study of nucleation and growth of particles led them to the following conclusions: The initial hydrocarbon is transformed by a gas phase reaction into macromolecules. The partial pressure of the macromolecules increases with reaction time until a supersaturation is high enough to induce condensation of macromolecules into droplets. The formation of liquid nuclei eliminates the supersaturation, and the formation of additional liquid nuclei becomes impossible. The macromolecules which continue to be formed maintain the nuclei growth. The liquid droplets are pyrolysed into a solid material. A statistical study of the distribution curves of the particle diameters indicates that the growth rate of each particle is proportional to its diameter.