创新补贴、税收优惠与高新技术产业研发产出

论文探讨了政府的研发补贴、专利、知识产权补贴、成果转化补贴以及税收优惠等各种政策对高新技术企业创新产出的作用机制,并通过分样本研究深入分析各项补贴作用的差异性。结果表明,各项补贴的激励效果不仅在企业不同阶段的研发产出间不同,在不同产权性质、不同规模、不同行业的高新技术企业间亦存在差异。因此要提高政府研发补助的效果:一是要坚持对研发补助的精细化管理,依据补助目的灵活运用各项补助政策;二是政府仍需优化资源配置,针对不同产权性质、不同规模、不同产业的企业实施差异化的补助策略,最大限度发挥各项补助资源对企业研发产出的激励作用。

咔唑及其衍生物在蓝光OLED中的应用

咔唑及其衍生物因其特有的电学性能、电化学性能和光物理性能而被广泛研究。由于这类材料不仅可以作为良好的空穴传输材料,而且在咔唑化合物的不同位置引入电子传输修饰基团,可以使得电子和空穴更加易于注入,并且可以很好地调节两者的平衡,因此,咔唑及其衍生物被认为是一类重要的蓝光荧光材料。咔唑及其衍生物不仅可以以小分子形式应用到蓝光荧光材料、蓝光磷光材料和热致延迟荧光材料,同样可以以高分子形式应用到蓝光荧光材料中。近年来,关于咔唑及其衍生物发光材料的合成及应用成为蓝光OLED研究的热点。本文综述了近年来国内外小分子咔唑及其衍生物作为蓝光有机电致发光主体材料的研究状况,对其分子结构设计光、电子轨道结构、物理性质、热学性质、电化学性质及器件性能等方面作了详细归纳比较,同时归纳了含咔唑结构的聚合物蓝光有机电致发光材料的研究进展,最后展望了咔唑基蓝光有机电致发光主体材料的发展前景和趋势。从光电转换效率及价格方面来说,热致延迟荧光材料和聚合物(含咔唑类基团)发光材料是最具有前景的蓝光OLED材料。

Preparation Technology of Solvent-free Polyurethane:A Mini-Review

Solvent-free polyurethanes are synthesized under certain conditions via a rapid reaction between liquid prepolymers.During this process the molecular weight of the polymer is rapidly increased to produce polymeric materials containing a carbamate-based structure at a very fast rate.The organic solvents are completely avoided in the solvent-free polyurethane synthesis process,thus avoiding all the problems associated with the use of organic solvents.Solvent-free polyurethane synthetic leather is extruded directly without adding solvents in the production and processing process,which has the advantages of low VOC emission and environmentally friendly.This review brings together theoretical and experimental research on the application and synthesis and preparation of solvent-free polyurethanes to generate an understanding of the theory and synthesis and preparation techniques associated with solvent-free polyurethanes.The review includes(i)the application and development direction of solvent-free polyurethane,(ii)an overview of the technology of solvent-free polyurethane synthetic leather preparation,(iii)a study of the modification and synthesis of solvent-free polyurethane prepolymers,(iv)a summary of the technology of rapid foam forming of solvent-free polyurethane and its influencing factors,(v)a review of the technology of solvent-free polyurethane synthetic leather preparation.In addition to the review,a corresponding overview of the theoretical and experimental advances in solvent-free delayed foaming technology in recent years and a summary of the technology and experience in the preparation of solvent-free polyurethanes are also presented.

Synthesis and Characterization of Polyimides Based on Twisted Non-coplanar Backbone Containing Indolocarbazole

A diamine monomer(4,4’-(((5,11-dihydroindolo[3,2-b]carbazole-6,12-diyl)bis(4,l-phenyl-ene))bis(oxy))dianiline)containing a rigid conjugated indolocarbazole was designed and synthesized through a three-step reaction.A series of high-performance functional polyimides were prepared through simple condensation polymerization of the monomer with different industrial dianhydrides 6FDA,BTDA and ODPA,respectively,which exhibit superior thermal stability,good solubility in polar organic solvents and good mechanical properties.The glass transition temperature(T_(g))is above 334℃,and the 5%weight loss temperature(T_(d5%))of polyimides under nitrogen atmosphere falls in the range of 502〜526℃.The tensile strength and tensile modulus are 49.45~60.08 MPa and 1.4-1.6 GPa,respectively.In addition,the maximum fluorescence emission wavelength of polyimides in the NMP solution(0.02 mg/mL)are around 448 nm with blue light emission and 451 nm as film without significant red shift,which indicates the prepared polyimides process a certain application potential in high-performance flexible polymer optoelectronic devices.