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SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

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chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： Ying-nan Xuan Yan Gao yong huang Xi-gao Jian laboratory of cellulose and lignocellulosics chemistry guangzhou institute of chemistry chinese academy of sciences, guangzhou 510650 china institute of chemistry chinese academy of sciences, beijing 100080 china Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012, china chinese Acad Sci Guangzhou Inst Chem Lab Cellulose & Lignocellulos Chem Guangzhou 510650 Peoples R China

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group

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聚丙烯微孔膜的研究进展

现代化工 2004年第10期24卷 19-22页

作者：臧亚南丁恩勇中国科学院广州化学研究所纤维素化学重点实验室

介绍了由熔融纺丝-冷却拉伸法和热致相分离法制备聚丙烯微孔膜的原理和过程。对当前膜研究领域的热点即膜的亲水化改性研究进行了重点评述,包括暂时性改性和永久性改性。阐述了各种改性方法的特点,着重讨论了亲水化改性对膜性能如膜的... 详细信息

介绍了由熔融纺丝-冷却拉伸法和热致相分离法制备聚丙烯微孔膜的原理和过程。对当前膜研究领域的热点即膜的亲水化改性研究进行了重点评述,包括暂时性改性和永久性改性。阐述了各种改性方法的特点,着重讨论了亲水化改性对膜性能如膜的微孔孔径、孔隙率、透水量等的影响,强调膜表面亲水性的提高可改善膜的耐生物污染性。指出聚丙烯微孔膜的应用领域和发展前景。

关键词：聚丙烯微孔膜亲水性

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乙基氰乙基纤维素溶致液晶的缺陷结构观察

纤维素科学与技术 1993年第4期1卷 11-16页

作者：黄勇中国科学院广州化学研究所纤维素化学开放研究实验室广州510650

乙基氰乙基纤维素在许多溶剂中都可以形成胆甾型液晶溶液。在液晶溶液中出现多种向错结构。本文利用偏光显微镜和电子显徽镜对液晶溶液中出现的向错结构进行了全面的观察。观察到了λ,τ和x向错线以及各种由具有相反符号的λ和τ向错线... 详细信息

乙基氰乙基纤维素在许多溶剂中都可以形成胆甾型液晶溶液。在液晶溶液中出现多种向错结构。本文利用偏光显微镜和电子显徽镜对液晶溶液中出现的向错结构进行了全面的观察。观察到了λ,τ和x向错线以及各种由具有相反符号的λ和τ向错线组成的向错对,其结构特征与小分子胆甾型液晶相结构特征相似。

关键词：纤维素液晶向错结构缺陷

光聚合对乙基氰乙基纤维素/丙烯酸胆甾相结构的影响

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纤维素科学与技术 2001年第4期9卷 1-10页

作者：张冠琦黄勇中国科学院广州化学研究所纤维素化学开放研究实验室中国科学院化学研究所北京100080

乙基氰乙基纤维素 [(E -CE)C]能够很好地溶解在丙烯酸 (AA)中并形成胆甾型液晶溶液。在 (E -CE)C/AA溶液中加入适当的光引发剂 ,采用紫外光引发聚合抑制聚合过程中相分离的发生 ,可以制得保持胆甾相结构的复合物。聚合反应会对胆甾相的... 详细信息

乙基氰乙基纤维素 [(E -CE)C]能够很好地溶解在丙烯酸 (AA)中并形成胆甾型液晶溶液。在 (E -CE)C/AA溶液中加入适当的光引发剂 ,采用紫外光引发聚合抑制聚合过程中相分离的发生 ,可以制得保持胆甾相结构的复合物。聚合反应会对胆甾相的结构产生一定的影响。文章研究了溶液浓度、聚合温度和 (E -CE)C分子量等因素对聚合以后胆甾相选择反射光波长及结构的影响。

关键词：乙基氰乙基纤维素丙烯酸胆甾型液晶复合物光聚合

分子结构对乙基氰乙基纤维素/丙烯酸胆甾型液晶性的影响

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纤维素科学与技术 2001年第3期9卷 1-10页

作者：张冠琦周雪松李静黄勇中国科学院广州化学研究所纤维素化学开放研究实验室中国科学院化学研究所北京100080

乙基氰乙基纤维素 [(E -CE)C]可溶于丙烯酸 (AA)形成胆甾型溶致液晶体系 ,液晶溶液的临界浓度 (C1 )与 (E -CE)C的分子量 (MW)有关 ,MW 越高 ,C1 越低。同时 ,C1 还受 (E -CE)C氰乙基取代度 (DS)的影响 ,DS越大 ,C1 越低。相同DS时 ,胆... 详细信息

乙基氰乙基纤维素 [(E -CE)C]可溶于丙烯酸 (AA)形成胆甾型溶致液晶体系 ,液晶溶液的临界浓度 (C1 )与 (E -CE)C的分子量 (MW)有关 ,MW 越高 ,C1 越低。同时 ,C1 还受 (E -CE)C氰乙基取代度 (DS)的影响 ,DS越大 ,C1 越低。相同DS时 ,胆甾相的螺距 (P)随MW 增加而增大 ;在MW 相近时 ,随DS的升高 ,P先减小 ,后增大 ,在DS 0 .2～ 0 .3之间有最小值。P随 (E -CE)C/AA溶液浓度的增大而降低。 (E -CE)C/AA溶液中的AA快速聚合后 ,体系胆甾相选择性反射光的能力和选择性均有所降低 ,并且最大选择性反射光的波长 (λmax)蓝移。聚合前溶液的浓度越小。

关键词：乙基氰乙基纤维素胆甾型液晶分子量取代度聚合复合物分子结构丙烯酸

Decoration of disclinations by solidification-induced band texture and focal-conic texture for a low-molar-mass liquid crystal

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chinese Science Bulletin 2002年第20期47卷 1711-1713页

作者： GU Qincui WU Changcheng CHEN Shouxi huang yong State Key laboratory of Polymer Physics and chemistry Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080China laboratory of cellulose and lignocellulosics chemistry Guangzhou Institute of ChemistryChinese Academy of SciencesGuangzhou 510650China

Two decoration techniques, solidification-induced band texture decoration and focal-conic texture decoration, have been established to exhibit the director field of disclinations in a low-molar-mass methacrylate liquid crystal. The disclinations with strength s=1/2 and s=±1 are observed by the two decoration methods. For the solidification-induced band texture decoration, the molecular orientation is perpendicular to the direction of the band. While for focal-conic texture decoration, it has been proved by the results of IR dichroism that the direction of the director is parallel to the direction of the focal-conic. Therefore, the sketch map of the molecular director filed can be mapped according to the morphological pattern of the solidification-induced band texture or focal-conic texture.

关键词： decoration disclination solidification-induced band texture focal-conic texture liquid crystal.

Preparation and properties of poly(lactic acid)/cellulolytic enzyme lignin/PGMA ternary blends

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chinese Chemical Letters 2012年第3期23卷 351-354页

作者： Wen Zhu Ouyang yong huang Hong Jun Luo Dong Shan Wang laboratory of cellulose and lignocellulosics chemistry Guangzhou Institute of ChemistryChinese Academy of SciencesGuangzhou 510650China National Engineering Research Center for Engineering Plastics Technical Institute of Physics&ChemistryChinese Academy of SciencesBeijing 100190China

Poly（lactic acid）-based ternary blends consisting of poly（lactic acid）（PLA）,cellulolytic enzyme lignin（CEL）,and polyolefine grafting maleic anhydride（PGMA） were prepared by extrusion blending and the mechanical properties and the morphology of the ternary blends were *** was found that the mechanical properties varied with various loading of the components in the *** to neat PLA,the tensile strength and the Young＇s modulus of the ternary blends were decreased,but the elongation at break and the impact strength were effectively *** electron microscope observations revealed that the CEL plays a bridging role between PLA and PGMA,enhancing the miscibility between them and resulting in the improvement of ductility and toughness of the ternary *** the cost and performance,we obtained the optimal blend PLA/CEL/ PGMA（80/20/20,w/w/w）,of which the impact strength and the elongation at break were doubled as that of neat PLA,and the tensile strength remained moderate.

关键词： Polycaprolactone Cellulolytic enzyme lignin Tougher Blends

Lignin-Containing cellulose Nanomaterials:A Promising New Nanomaterial for Numerous Applications

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Journal of Bioresources and Bioproducts 2019年第1期4卷 3-10页

作者： Chinomso M.EWULONU Xuran LIU Min WU huang yong Technical institute of Physics and chemistry Chinese Academy of SciencesBeijing 100190China Department of Polymer and Textile Engineering Nnamdi Azikiwe UniversityP.M.B.5025AwkaNigeria University of chinese academy of sciences Beijing 100039China

The demand for sustainable functional materials with an eco-friendly preparation process is on the *** has been attributed as the most sustainable bioresource on earth which can meet the stringentrequirements of functionalization. However, cellulose nanomaterials obtained from lignocellulosics which has reachedadvanced stages as a sustainable functional material is challenged by its preparation procedures. These procedures can notbest be described as sustainable and eco-friendly owning to lots of energy and chemicals spent in the pre-treatment andpurification processes. These processes are intended to aid fractionation into the major components in order to removelignin and hemicellulose for the production of cellulose nanomaterials. This work is thus centred on reviewing theprogress achieved in introducing a new cellulose nanomaterial containing lignin. The preparation processes, propertiesand applications of this new lignin-containing cellulose nanomaterial will be discussed in order to chart a sustainablepreparation route for cellulose nanomaterials.

关键词： lignocellulose nanofibers pre-treatment bioresources lignin biomass nanocellulose

Rheological and DSC Studies on the Interaction between κ-Carrageenan and cellulose Nanocrystals (CNC)

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chinese Chemical Letters 2006年第5期17卷 695-698页

作者： Rui GUO En yong DING Key laboratory of cellulose and lignocellulosics chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou 510650 Graduate School of the chinese academy of sciences Beijing 100039

Rheometer and differential scanning calorimetry （DSC） have been used to probe the mechanism of gelation in gels formed by mixture of k-carrageenan and cellulose nanocrystals （CNC）. The results indicated that an as... 详细信息

关键词： Rheology DSC r-carrageenan cellulose nanocrystals (CNC).