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Understanding cellulose dissolution： effect of the cation and anion structure of ionic liquids on the solubility of cellulose

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Science China Chemistry 2016年第11期59卷 1421-1429页

作者： Jinming Zhang Lili Xu Jian Yu Jin Wu Xiaoyu Zhang jiasong he Jun Zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Shandong henglian New Materials Co. Ltd. Weifang 261061 China

The effect of ionic liquids(ILs) on the solubility of cellulose was investigated by changing their anions and cations. The structural variation included 11 kinds of cations in combination with 4 kinds of anions. The interaction between the IL and cellobiose, the repeating unit of cellulose, was clarified through nuclear magnetic resonance(NMR) spectroscopy. The reason for different dissolving capabilities of various ILs was revealed. The hydrogen bonding interaction between the IL and hydroxyl was the major force for cellulose dissolution. Both the anion and cation in the IL formed hydrogen bonds with cellulose. Anions associated with hydrogen atoms of hydroxyls, and cations favored the formation of hydrogen bonds with oxygen atoms of hydroxyls by utilizing activated protons in imidazolium ring. Weakening of either the hydrogen bonding interaction between the anion and cellulose, or that between the cation and cellulose, or both, decreases the capability of ILs to dissolve cellulose.

关键词： cellulose ionic liquids dissolution mechanism cellobiose

Transparent and flame retardant cellulose/aluminum hydroxide nanocomposite aerogels

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Science China Chemistry 2016年第10期59卷 1335-1341页

作者： Bin Yuan Jinming Zhang Jian Yu Rui Song Qinyong Mi jiasong he Jun Zhang Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences College of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Sino-Danish Center for Education and Research Sino-Danish College at University of Chinese Academy of Sciences

Cellulose-based nanocomposite aerogels were prepared by incorporation of aluminum hydroxide(AH) nanoparticles into cellulose gels via in-situ sol-gel synthesis and following supercritical CO_2 drying. The structure and properties of cellulose/AH nanocomposite aerogels were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy,ultraviolet-visible spectrometry, N_2 adsorption, thermogravimetric analysis, and micro-scale combustion calorimetry. The results indicated that the AH nanoparticles were homogeneously distributed within matrix, and the presence of AH nanoparticles did not affect the homogeneous nanoporous structure and morphology of regenerated cellulose aerogels prepared from1-allyl-3-methylimidazolium chloride solution. The resultant nanocomposite aerogels exhibited good transparency and excellent mechanical properties. Moreover, the incorporation of AH was found to significantly decrease the flammability of cellulose aerogels. Therefore, this work provides a facile method to prepare transparent and flame retardant cellulose-based nanocomposite aerogels, which may have great potential in the application of building materials.

关键词： cellulose nanocomposite aerogel flame retardant transparent aluminum hydroxide ionic liquid

Mating Ethogram of a Video-aided Study of Mating and Parturition in Captive Chinese Crocodile Lizards (Shinisaurus crocodilurus)

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Asian herpetological Research 2019年第4期10卷 253-260页

作者： Chengming HUANG Zhengjun WU Shuyi LUO jiasong he Chunsheng YANG Meng MENG Lu YAO Zhigao ZENG Key Laboratory of Animal Ecology and Conservation Institute of ZoologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541004China Guangxi Key Laboratory of Rare and Endangered Animal Ecology Guangxi Normal UniversityGuilin 541004China Daguishan National Nature Reserve HezhouGuangxi 542800China Chinese Wildlife Conservation Association Beijing 100110China Department of Mammalogy American Museum of Natural HistoryNew York 10024USA Department of Anthropology Hunter CollegeNew York 10065USA

Mating behavior and parturition are important components in the life history of any species. The endangered Chinese crocodile lizard(Shinisaurus crocodilurus) is suffering dramatic population decreases in the wild. Successful captive breeding can provide individuals to be reintroduced into their natural habitat and help to restore the wild populations. Studying the mating behavior and parturition of these lizards in captivity will enable us understand how is this ancient species reproduction and optimize artificial reproduction protocol. We studied the mating behavior and parturition of Chinese crocodile lizards in captivity using video recordings at the Daguishan National Nature Reserve, China, from 2015 to 2017. We analyzed pre-copulation and copulation, which occurred in mid-March to late May from all studied years. Pre-copulation and copulation lasted on average 7.51(n=11) and 27.45(n=11) minutes, respectively. We found that large-bodied male lizards have longer copulation periods, a pattern seen in other lizard species. In the mating event, males always initiated sex, while the females were passive. The duration of parturition lasted 153.8 ± 26.8(n=46) minutes, and larger females had heavier clutches. In addition, even though Chinese crocodile lizards represent an ancient lizard clade with primitive characteristics, they still abide by the reproduction patterns seen in most other lizard species.

关键词： lizard mating and reproduction behavior quantitive study

COMPATIBILIZATION OF NYLON 6/LCP IN-SITU COMPOSITES

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COMPATIBILIZATION OF NYLON 6/LCP IN-SITU COMPOSITES

INTERFACIAL CHARACTERIZATION FOR COMPATIBILIZED POLYSULFONE/VECTRA B950 BLENDS

International Symposium on Engineering Plastics EP’2001 Beijing

作者： Xuejing Zheng jiasong he State Key Laboratory of Engineering Plastics Center for Molecular Science Institute of ChemistryChinese Academy of Sciences

＜正＞Introduction In-situ composites containing a thermotropic liquid crystalline polymer（LCP）is one group of particular attractive materials,owing to their specific rheological and mechanical performance[1-3].LCP tends to form fibrous structure in the shear or elongationai field,due to its rigid rod-like macromolecular *** the inherent strength and stiffness of the thermotropic LCP,these fibrous inclusions would then act as reinforcement,

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INTERFACIAL CHARACTERIZATION FOR COMPATIBILIZED POLYSULFONE/...

IN-SITU HYBRID COMPOSITES CONTAINING REINFORCEMENTS AT TWO ORDERS OF MAGNITUDE

International Symposium on Engineering Plastics EP’2001 Beijing

作者： Jun Zhang jiasong he State Key Laboratory of Engineering Plastics Center for Molecular ScienceInstitute of ChemistryThe Chinese Academy of Sciences

＜正＞Thermotropic liquid crystalline polymers（TLCPs）can form fibrillar morphologies in melt processing operations that often incorporate elongational flow ***,their application as reinforcements in polymer composites has been developed since the mid to late eighties by several research groups[1-4].Such composites are often referred to as in situ *** technology and properties of in situ composites have been

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IN-SITU HYBRID COMPOSITES CONTAINING REINFORCEMENTS AT TWO O...

引入离子基团改善聚苯乙烯和热致液晶聚合物的相容性 Ⅰ热性能和形态

International Symposium on Engineering Plastics EP’2001 Beijing

作者： jiasong he Yuli Wang Hongzhi Zhang State Key Laboratory of Engineering Plastics Center for Molecular ScienceInstitute of ChemistryThe Chinese Academy of Sciences

＜正＞In order to overcome the poor processabiliry of short fibre-reinforced thermoplastics and to enhance the mechanical performance of thermotropic liquid crystalline polymer（TLCP）fibrils-reinforced thermoplastics（in-situ composites）,a new concept of in-situ hybrid composite has been put forward[1].This group of polymer-matrix composites,basically consisting of a thermoplastic matrix,inorganic fibres of micrometres in

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高分子学报 1998年第3期8卷 196-202页

作者：刘杰何嘉松中国科学院化学研究所工程塑料国家重点实验室

ＤＳＣ和ＳＥＭ研究结果表明聚苯乙烯（ＰＳ）与一种热致液晶聚合物（ＬＣＰ）（ＰＨＢ／ＰＥＴ（６０／４０）共聚酯）完全不相容．共混体系具有与组分无关的Ｔｇ，并且表现出明显的两相结构．将ＰＳ进行化学改性（引入磺酸基团）制备... 详细信息

ＤＳＣ和ＳＥＭ研究结果表明聚苯乙烯（ＰＳ）与一种热致液晶聚合物（ＬＣＰ）（ＰＨＢ／ＰＥＴ（６０／４０）共聚酯）完全不相容．共混体系具有与组分无关的Ｔｇ，并且表现出明显的两相结构．将ＰＳ进行化学改性（引入磺酸基团）制备成磺化聚苯乙烯（ＳＰＳ），随中和盐离子的变化有：酸式、Ｌｉ、Ｎａ、Ｚｎ和Ｍｎ盐五种形式．用ＤＳＣ和ＳＥＭ对ＬＣＰ与ＳＰＳ共混物的热性能和形态进行了分析和表征．共混体系有一个与组成相关，且明显低于纯ＳＰＳ的Ｔｇ．这表明了ＰＳ与ＬＣＰ的相容性因为磺酸基团的引入而得到了改善．同时用Ｆｏｘ方程计算了ＬＣＰ的Ｔｇ．当ＳＰＳ含量较低时（不大于５０％）在各个共混体系中，所估算的ＬＣＰ的Ｔｇ相互吻合．表明共混体系满足Ｆｏｘ方程的前提条件，即ＬＣＰ与ＳＰＳ形成相容体系．当ＳＰＳ含量较低时（２５％），ＬＣＰ／ＳＰＳ的共混物为较均一体系，断面光滑；而ＳＰＳ含量较高时，在脆断面可以观察到纳米级的颗粒．电子能谱分析证明了这些颗粒是ＳＰＳ负离子的聚集体．

关键词：增容剂相容性离聚物热致液晶 LCP SPS

LCP微球对LCP/尼龙6共混体系力学性能的影响

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复合材料学报 2009年第2期26卷 47-53页

作者：郑学晶何嘉松郑州大学材料科学与工程学院郑州450052 中国科学院化学研究所工程塑料重点实验室北京100190

制备了分散相呈球状微粒形貌的液晶聚合物/尼龙6(LCP/PA6)共混体系,选用离聚物磺化聚苯乙烯锌盐(Zn-SPS)和反应性嵌段共聚物苯乙烯-马来酸酐共聚物(SMA)作为体系的增容剂,探讨了在相间相互作用得以改善时,利用LCP微球改善LCP/尼龙6共混... 详细信息

制备了分散相呈球状微粒形貌的液晶聚合物/尼龙6(LCP/PA6)共混体系,选用离聚物磺化聚苯乙烯锌盐(Zn-SPS)和反应性嵌段共聚物苯乙烯-马来酸酐共聚物(SMA)作为体系的增容剂,探讨了在相间相互作用得以改善时,利用LCP微球改善LCP/尼龙6共混体系韧性的可能性。试样受拉后的形貌观察表明,在增容体系中,LCP微球很好地镶嵌在尼龙6基体中,粒子脱落的空洞发生了较大的形变。力学性能测试结果表明,LCP的加入使材料的拉伸强度低于纯尼龙6,加入增容剂后共混材料拉伸强度有所提高,其中LCP/PA6(质量比10/90)共混体系增容后的拉伸强度与纯尼龙6相当。所研究的增容体系的拉伸断裂吸收能均比未增容体系有所增加。其中,当LCP的质量分数为4%时,Zn-SPS增容体系的拉伸断裂吸收能比未增容体系和纯尼龙6分别增加了12%和62%;当LCP的质量分数为10%时,SMA增容体系的拉伸断裂吸收能比未增容体系和纯尼龙6分别增加了46%和55%。表明在适当条件下,利用LCP微球可以在保持共混体系的拉伸强度的同时提高材料的韧性。

关键词：尼龙6 液晶聚合物共混物增容力学性能

尼龙6/液晶聚合物共混体系中化学反应对体系热行为及形貌的影响

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高分子学报 2008年第12期18卷 1160-1165页

作者：郑学晶何嘉松郑州大学材料科学与工程学院郑州450052 中国科学院化学研究所高分子科学与材料联合实验室工程塑料重点实验室北京100190

采用漫反射红外光谱法(DRIFT)和示差扫描量热法(DSC)研究了2种不同特性黏数的尼龙6与3种液晶聚合物(Vectra A950、Vectra B950和Rodrun LC5000)之间的酯-酰胺交换反应.DRIFT测试证实了尼龙6与LC5000之间存在化学反应.DSC分析表明,酯-酰... 详细信息

采用漫反射红外光谱法(DRIFT)和示差扫描量热法(DSC)研究了2种不同特性黏数的尼龙6与3种液晶聚合物(Vectra A950、Vectra B950和Rodrun LC5000)之间的酯-酰胺交换反应.DRIFT测试证实了尼龙6与LC5000之间存在化学反应.DSC分析表明,酯-酰胺交换反应使体系中尼龙6的熔点下降、结晶度降低.增加反应时间和增大共混体系中液晶聚合物的含量有利于酯-酰胺交换反应的发生.与Vectra A950和Vectra B950相比,分子链柔性较强的Rodrun LC5000与尼龙6之间的化学反应更容易进行.扫描电子显微镜(SEM)观察表明,随着共混时间的延长,分散相形貌由球状粒子发展为短棒状纤维,乃至最终形成直径更细的微纤结构.

关键词：尼龙6 液晶聚合物酯-酰胺交换反应