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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 {2. 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 中科院广州化学所 Laboratory of Cellulose and Lignocellulosics Chemistry CAS Guangzhou 510650 Department of Polymer Science College of Chemical Engineering Dalian University of Technology Dalian 116012

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 (2.)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2.O3 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

Size Effects of Nano-crystalline cellulose

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chinese Chemical Letters 2003年第9期14卷 977-978页

作者： Guo Kang LI, Xiao Fang LI, yong JIANG, Mei Zhen ZENG, En yong DINGKey {2. of cellulose and lignocellulosics chemistry guangzhou institute of chemistry, chinese academy of sciences, guangzhou 510650 Key Lab. cellulose/L. Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou 510650 China

Natural cellulose with the crystal form of cellulose Ⅰ, when treated with condensed lye (e.g. 18%NaOH), can change into new crystal form of cellulose Ⅱ. But the nano-crystalline cellulose (NCC) can do it when only treated with dilute lye (e.g. 1%NaOH) at room temperature and even can dissolve into slightly concentrated lye (e.g. 4%NaOH).

关键词： cellulose Ⅰ cellulose Ⅱ nano-crystalline cellulose.

A METHOD OF PREPARING SPHERICAL NANO-CRYSTAL cellulose WITH MIXED CRYSTALLINE FORMS OF cellulose Ⅰ AND Ⅱ

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chinese Journal of Polymer Science 2001年第3期19卷 291-296页

作者： Xiao-fang Li En-yong Ding Guo-kang Li laboratory of {2. and lignocellulosics chemistry, guangzhou institute of chemistry, chinese academy of sciences, guangzhou 510650 china College of Material Science and Engineering South china University of Technology, guangzhou 510641, china 中科院广州化学所广东广州

A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our products are preparedfrom natural cotton fibers. The products are of spherical shape with mixed crystal forms of cellulose I and II. The preparationconditions determine the properties of the products. Prior treatment is a critical procedure. The properties of the products arealso strongly affected by such conditions as the kinds of acids used, the ratio of the acid mixture, the acid concentration, theultrasonic agitation time and hydrolysis temperature. The number average molecular weight of NCC is determined by gelpermeation chromatography (GPC). The particle size and shape were determined by transmission electron microscopy(TEM). X-ray diffraction was used to detect the crystallinity and average crystallite size of the panicle.

关键词： Spherical nano-crystal cellulose Mixed crystal forms of cellulose Ⅰ and Ⅱ, Ultrasonic agitation

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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

STUDIES ON PREPARATION OF CELLUIOLYTIC ENZYME LIGNIN OF RICE STRAW

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STUDIES ON PREPARATION OF CELLUIOLYTIC ENZYME LIGNIN OF RICE...

第二届国际非木材纤维制浆造纸会议

作者： Xiang-hui Wen Hui-sheng Yu Shi-yu Fu Xiu-yu huang. Jian-ying Chen and Jun Lu laboratory of {2. and lignocellulosics chemistry (LCLC) guangzhou institute of chemistry chinese academy of sciences P.O. Box 112. guangzhou {12.

＜正＞To search a more satisfied procedure preparing cellulolytic enzyme lignin （CEL） of rice straw, the conditions of ball milling and enzymic hydrolysis were optimized. The results indicated that enzymic hydrolysis of unmilled rice straw meal was very mild, even though prolonging the duration of enzymolysis. exchanged with fresh enzyme solution or increasing amount of cellulase for enzymolysis were adopted. Two hour milling as a pretreatment of straw meal is necessary and reasonable for the preparation of rice straw CEL according the changes of crystal Unity and the size of crystal grain and the efficiency of enzymic hydrolysis and considered to aviod the changes of molecular weight and functional groups of isolating lignin. The increase of the amount of cellulase can obtain the same efficiency of enzymic hydrolysis as prolonging time of milling does. Less than 3 FPU cellulase activety per gram of straw meal in the amount of cellulase will influence on enzymic hydrolysis of straw meal. CEL-96 of 38.6% rice straw Klason lignin and the extract of 12.7% rice straw Klason lignin can be extracted by 96% aqueous dioxane and 50% dioxane respectively,and 2..8% purified CEL-96 can be obtained. *** 10% of Klason lignin is isolated as milled grass lignin （MGL） according Bjorkman procedure. Rice straw CEL contains more chemically associated carbohydrate with lignin and the fraction of lignin extracted with 50% aqueous dioxane can not be purified by dissolving in 90% acetic acid and precipitating in water.

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来源： cnki会议评论

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纳米晶体纤维素Ⅱ的制备与表征研究

纤维素科学与技术 2002年第2期10卷 12-19页

作者：黎国康丁恩勇李小芳姜勇中国科学院广州化学研究所纤维素化学重点实验室广州510650

用硫酸水解棉短绒得到的纳米晶体纤维素Ⅰ(NCC-Ⅰ),经1%的NaOH处理后就可得到纳米晶体纤维素Ⅱ(NCC-Ⅱ)。用X-射线衍射仪、TEM、AFM、FITR和GPC表征,证明NCC-Ⅰ有低的分子量、窄的分子量分布及较高的化学活性;在FTIR谱中,NCC-Ⅰ的羟基... 详细信息

用硫酸水解棉短绒得到的纳米晶体纤维素Ⅰ(NCC-Ⅰ),经1%的NaOH处理后就可得到纳米晶体纤维素Ⅱ(NCC-Ⅱ)。用X-射线衍射仪、TEM、AFM、FITR和GPC表征,证明NCC-Ⅰ有低的分子量、窄的分子量分布及较高的化学活性;在FTIR谱中,NCC-Ⅰ的羟基波数较之棉短绒的羟基波数有明显的蓝移现象。研究证明纳米晶体纤维素具有十分明显的纳米效应。

关键词：制备表征研究纳米晶体纤维素I 纳米晶体纤维素Ⅱ 结晶结构

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含氯漂白废水的电氧化处理

纤维素科学与技术 2002年第3期10卷 40-46页

作者：刘乐文欧义芳黄秋莲中国科学院广州化学研究所纤维素化学重点实验室广州510650

以二氧化铅为阳极,不锈钢网为阴极,用电化学氧化法处理多段漂白废水中的有害物质。其中二氧化铅电极是通过在碳棒上电镀而成的。研究发现,废水的电导率和pH值对于不同的废水在电化学氧化过程中的变化是不同的;而废水的COD和色度在整个... 详细信息

以二氧化铅为阳极,不锈钢网为阴极,用电化学氧化法处理多段漂白废水中的有害物质。其中二氧化铅电极是通过在碳棒上电镀而成的。研究发现,废水的电导率和pH值对于不同的废水在电化学氧化过程中的变化是不同的;而废水的COD和色度在整个过程中一直减少;氯化木质素的分子量和分子量分布发生了变化。

关键词：造纸含氯漂白废水电氧化处理二氧化铅电极