含氟聚酰亚胺及其在微电子工业中的研究进展I含氟单体及聚酰亚胺的合成

综述了近年来国内外在含氟聚酰亚胺(PI)研究及应用领域中的最新进展情况。主要从含氟二胺单体、二酐单体及含氟聚酰亚胺在合成方面的研究进展情况进行了详细的综述。重点阐述了中国科学院化学研究所305组近几年在这方面的研究进展情况，并指出为了推动含氟聚酰亚胺这类具有优良综合性能的功能材料在工业上的广泛应用，就必须首先解决含氟单体种类较少这个制约含氟聚酰亚胺发展的瓶颈问题。     

新型聚苯并咪唑的研究进展

聚苯并咪唑是一类重复基元含苯并咪唑结构的芳香杂环聚合物,具有耐高温、耐腐蚀、高机械强度、高阻燃性等特点,被广泛应用于耐高温质子交换膜、防火阻燃及航空航天领域。近年来,各种不同结构的新型聚苯并咪唑不断被合成报道,新颖的结构基元赋予聚苯并咪唑改善的溶解性、提升的抗氧化性、高的酸负载水平及多孔特性,进一步拓展了聚苯并咪唑在吸附分离及燃料电池方面的应用。综述了新型聚苯并咪唑的研究进展,重点介绍了新型聚苯并咪唑的结构种类及其功能应用,旨在促进聚苯并咪唑研究的发展。     

聚苯撑的合成、性能及其应用

对直链型、树枝形聚苯撑的合成、性能及其应用作了介绍，并着重描述了聚苯撑的应用。     

芳杂环聚苯并噁唑材料的合成研究进展

聚苯并噁唑是一种高性能芳杂环聚合物,具有高强度、高模量、高耐辐射、热稳定性及化学稳定性优异等优点,在航空、航天、微电子等高新技术领域具有广阔的应用前景。近年来,有关聚苯并噁唑的研究报道越来越多,这类材料可能的应用领域随之不断被拓宽,但是多偏重于该类材料光物理和光化学的性质与应用,以及在高强度纤维和光致抗蚀剂等方面的应用,而在单体合成方面的研究相对较少。本文主要综述聚苯并噁唑的合成方法及性能研究等方面的工作,并对聚苯并噁唑材料的应用前景进行展望。     

全(多)氟酰基过氧化物的化学及应用

综述了含氟新试剂全(多)氟酰基过氧化物的合成、热分解及其与富电子芳香族受物间的单电子转移反应的机理。并简要地介绍了它作为对芳环、芳杂环有效的全氟烷基化试剂及烯烃聚合的引发剂在合成含氟功能化合物领域中的重要应用。     

含氟聚酰亚胺及其在微电子工业中的研究进展Ⅱ含氟聚酰亚胺在微电子工业中的应用

综述了近年来国内外在含氟聚酰亚胺(PI)研究及应用领域中的最新进展情况。主要从现代微电子工业对相关材料的性能要求、标准型聚酰亚胺材料所面临的挑战以及新型含氟聚酰亚胺在微电子工业中的应用等几个方面进行了详细的综述。重点阐述了中国科学院化学研究所305组近几年在这方面的研究进展情况。并指出为了推动我国微电子工业的发展，研制开发低成本、高技术含量的含氟聚酰亚胺材料具有十分重要的现实意义．     

ATRP法合成含氟丙烯酸酯类聚合物的研究进展

含氟丙烯酸酯聚合物由于氟原子的改性作用而具有优异的表面特性,不仅稳定,具有很好的耐氧化和耐腐蚀性,而且具有较好的耐水、耐油及耐污性,可望在新材料的开发、理论研究和实际应用等方面获得广泛的应用.而原子转移自由基聚合(ATRP)又可为分子设计和合成提供很有效的途径,利用这种聚合可以获得预期结构和性能的含氟嵌段聚合物材料,充分发挥含氟元素的改性作用.本文综述了ATRP在丙烯酸氟烷基酯聚合物合成方面的应用,并介绍了国内外在此领域的研究状况.     

四丁基氟化铵的合成及其应用研究进展

四丁基氟化铵(TBAF)为重要的含氟有机化合物，广泛应用于有机合成中。综述了近年来TBAF的合成方法及其在氟化反应、硅醚脱保护、分子内环化及分子间环化等反应中的应用。并对底物适用范围、反应机理、反应条件等进行了探讨。     

含氟聚氨酯

(有关国外文献概述) 一九五八年英国专利首次报导了含氟聚氨酯的合成。六十年代国外对含氟聚氨酯进行了较广泛深入的研究。在美国,以国家宇宙航空局(NASA)为中心,在Narmco,3M.以及dupont等公司中进行了这方面的研究。在苏联,乌克兰高分子研究所等单位也进行了研究。Narmco.公司,为探索耐液氧和在纯氧中不燃的新材料,从一九六三年开始,合成了数种新的含氟聚酯二醇,聚醚二醇以及含氟二异氰酸酯,并在此基础上合成了一系列含氟聚氨酯。据初步统计,现已研究的含氟聚氨酯达五、六十种之多。含氟聚氨酯已成为聚氨酯的一个分支,也已成为含氟高聚物中的一个独立研究方向。     

耐高温含氟磺化聚苯并咪唑的合成及表征

采用5-磺酸钠间苯二甲酸、双(苯甲酸)六氟丙烷与3,3',4,4'-四氨基联苯在多聚磷酸中通过共缩聚反应, 合成了一系列磺化度(定义为100个重复单元中所含的磺酸基个数, SD)可控的含氟磺化聚苯并咪唑(sPBI), 并利用红外光谱、核磁共振、凝胶色谱和热失重分析等手段对其结构、分子量与热稳定性进行了表征, 还考察了其溶解性和成膜性. 结果表明, sPBI的数均分子量(M_n)为61300～86000, 多分散指数介于1.96～2.34之间, 并且sPBI具有良好的成膜性和优异的热稳定性能, 其5%和10%热失重对应温度均随着SD的增加而有所提高, 在SD为70%时分别为549和576 ℃. 此类聚合物在质子交换膜材料方面具有一定的应用前景.     

The wettability of fluoropolymer surfaces: influence of surface dipoles

The wettabilities of fluorinated polymers were evaluated using a series of contacting probe liquids ranging in nature from nonpolar aprotic to polar aprotic to polar protic. Fully fluorinated polymers were wet less than partially fluorinated polymers, highlighting the weak dispersive interactions of fluorocarbons. For partially fluorinated polymers, the interactions between the distributed dipoles along the polymer backbone and the dipoles of the contacting liquids were evaluated using both polar and nonpolar probe liquids. The results demonstrate that the surface dipoles of the fluoropolymers generated by substituting fluorine atoms with hydrogen or chlorine atoms can strongly interact with polar contacting liquids. The wettabilities of the partially fluorinated polymers were enhanced by increasing the density of dipoles across the surfaces and by introducing differentially distributed dipoles.     

Chiral side-chain liquid crystalline polysiloxanes bearing fluorinated mesogens and cholesteryl groups

A series of chiral side-chain liquid crystalline (LC) polysiloxanes bearing fluorinated mesogens were synthesized with a cholesteric LC monomer and a fluorinated nematic LC monomer. They were characterized by use of various experimental techniques, and effect of fluorinated mesogens on characteristic of LC polysiloxanes was studied as well. In photoluminescence spectra, a narrow and a broad peak occur at around 270-317 nm, originated, respectively, from fluorinated phenyl groups and the conjugated xenene structure. The specific rotation analysis of all polymers showed negative values, but absolute values were lower than those of the chiral monomers. All polymers showed smectic LC phase with very wide temperature ranges on heating and cooling cycles. Especially, only polymers bearing more fluorinated component exhibited smectic-cholesteric phase transition when they were heated. As the polymers contained more fluorinated mesogens, segregation of the fluorinated segment to the surface should occur at mesomorphic temperature. The highly ordered lamellar mesogen-siloxane matrix systems should be disturbed severely by separation of fluorinated mesogens, suggesting mesogenic orders transition from lamellar smectic to cholesteric phase.     

SYNTHESIS AND CHARACTERIZATION OF HETEROAROMATIC POLYMERS CONTAINING PYRIDINE MOIETIES

1. INTRODUCTION The new kinds of heteroaromatic polymers have been important topics in polymer science fields since they were developed at 1960s in order to meet demands for heat-resistant plastics for space and military applications. Because heteroaromatic polymers exhibit excellent thermal and chemical stability, outstanding electrical and mechanical properties, good solvent resistance, and dimensional stability, these polymers have found usage as adhesives, coatings, matrix resins, film…     

COMPARED PROPERTIES OF FLUORINATED HETEROCYCLIC COPOLYIMIDES

Various new fluorinated heterocyclic copolyimides have been synthesized by a polycondensation reaction of a diacid chloride containing imide, hexafluoroisopropylidene and methylene groups with aromatic or heteroaromatic diamines containing preformed phenylquinoxaline or 1,3,4-oxadiazole rings. Other fluorinated heterocyclic copolyimides have been prepared by a polycondensation reaction of the same diacid chloride with aromatic dihydrazides, bis(o-hydroxy-amine)s or a bis(o-carboxy-amine), resulting in intermediate polyhydrazides, poly(o-hydroxy-amide)s or poly(o-carboxy-amide), respectively, which were futher cyclodehydrated to the corresponding polyoxadia zole-imide, polybenzoxazole-imide or polybenzoxazinone-imide structure. These polymers showed good solubility in polar amidic solvents, such as N-methylpyrrolidinone (NMP) and dimethylformamide (DMF), and even in less polar liquids, like tetrahydrofurane or pyridine, except for those compounds containing benzoxazole rings which were less soluble, only on heating in NMP or DMF. The weight average molecular weight measured for tetrahydrofurane-fully-soluble polymers are in the range of 12800–26700 and the polydispersity is in the range of 2–5. All these polymers exhibited good thermal stability, with decomposition temperature being above 350°C, although somewhat lower than that of related polymers prepared by using fully aromatic diacid chlorides instead of the present ones containing methylene units. The glass transition temperature is in the range of 200–300°C. The dielectric constant measured for polymer films is in the range of 3.3–3.7. Tensile strength is in the range of 35–70 MPa, elongation to break between 30–40% and tensile modulus in the range of 170–330 MPa. A study of the relation between conformational parameters and properties of some of these polymers has been carried out by using the Monte Carlo method with an allowance for hindered rotation, and the values were compared with the experimental data and discussed in relation with the rigidity of the chains. The present polymers are potential candidates for use as high performance materials.     

Fluorination of polymers by sulfur hexafluoride gas under electric discharge

Fluorination of low-density polyethylene, polyacetylene, and poly(vinyl alcohol) was carried out using SF₆ gas under electric discharge. The polymers were partially fluorinated and the extent of fluorination was more in the case of poly (vinyl alcohol) than the other two polymers. The fluorinated polymers were characterized by elemental analysis (Fluorine), IR, and x-ray diffraction. Optical transparency of the films was also measured. The fluorinated polymers show better solvent resistance and decreased transparency than the virgin polymer. © 1994 John Wiley & Sons, Inc.     

含氟高分子基因载体

阳离子高分子被广泛应用为非病毒类基因载体,但这类高分子材料的转染效率与细胞毒性之间通常存在"恶性"关联,即获得高转染效率时往往会伴随严重的细胞毒性.如何制备兼具高效、低毒特点的高分子载体是成功实施基因治疗的关键.含氟高分子是一类具有独特理化性质的高分子,能够在低电荷密度条件下与核酸形成稳定的复合物,从而实现高效、低毒的基因转染.含氟功能基团可帮助阳离子高分子改善复合物稳定性、细胞内吞、内涵体逃逸、胞内核酸释放等多个环节,从而赋予了含氟高分子在基因递送过程中的氟效应.该专论系统地总结了含氟高分子基因载体的研究,介绍了含氟高分子的基因递送性能、作用机理以及在基因治疗、基因编辑中的应用,并对含氟高分子载体的未来发展进行了展望.     

Synthesis of New Fluoropolymers: Tailoring Macromolecular Properties with Fluorinated Substituents

The challenges and opportunities in the preparation of new fluoro- polymers are illustrated by the synthesis of fluorinated poly(ether sulfones), polyimides, and polyethers. Synthetic methods used for the preparation of new fluorinated monomers and polymers include anion-radical substitutions of perfluoroalkyl diiodides, nucleophilic additions to fluorinated olefins, perfluoroalkylsulfonyl-mediated nucleophilic sub-stitutions, and direct fluorinations with elemental fluorine. Properly placed fluorinated substituents can have significant effects on the dielectric properties, thermal stability, moisture absorption, permeability, phase transitions, and reactivity of the resulting polymers. In addition, fluorinated groups can enhance nonlinear optical effects and provide a method for chromophore alignment. The special behavior of partially fluorinated substituent groups offers unique tools for tailoring macro-molecular properties.     

New routes to organofluorine compounds based on ketenes and the radical transfer of xanthates

New routes to organofluorine derivatives based mostly on the powerful xanthate radical transfer technology are described. A special emphasis is placed on the synthesis of trifluoromethyl-substituted structures, including trifluromethyl ketones and fluorinated aromatic and heteroaromatic substances of interest to the pharmaceutical and agrochemical industries.     

Synthesis and Bioactivity of Novel Fluorinated Heteroaromatic Ureas

In order to find new urea cytokinins, a series of novel fluorinated heteroaromatic ureas have been designed and synthesized. The crystal structure of 3g was further determined by single crystal X-ray diffraction to obtain the structural feature of this class of urea compounds. The preliminary bioassay showed that some title compounds have good cytokinin activity.     

Stable superhydrophobic fluorine containing polyfluorenes

Fluorene-based polymers containing perfluorooctyl moieties were designed and synthesized.The high electronegativity and F…H-C interactions are present in the fluorinated polymers,which slightly induce blue-shift of UV-Vis absorption in film.The fluoropolymer films prepared from fluorinated solvents show lager contact angles than those prepared in non-fluorinated solvents.