董炎明
主要研究领域为高分子液晶、生物高分子甲壳素和塑料改性等。
个性化签名
- 姓名:董炎明
- 目前身份:
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学术头衔:
博士生导师
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学科领域:
高分子化学
- 研究兴趣:主要研究领域为高分子液晶、生物高分子甲壳素和塑料改性等。
1970年毕业于北京大学化学系。1978至1981年就读于北京化工学院高分子系并获硕士学位。1981至1994年在湘潭大学任讲师,副教授。1987年10月至1988年10月公派到英国剑桥大学材料系做访问学者,1988年10月至1989年4月任英国伯明翰大学化学系荣誉研究员。2001年日本福井大学材料学院客座教授。1994年至今为厦门大学材料系副教授,教授(博导)。目前是厦门大学高分子化学与物理学科的学术带头人,主持高分子化学与物理博士点与硕士点的日常工作。主要研究领域为高分子液晶、生物高分子甲壳素和塑料改性等。先后主持国家自然科学基金2项、863项目(副组长)、福建省自然科学基金2项、福建省科技重点项目以及横向课题等多项课题。已在国内外学术刊物上发表论文140余篇,其中SCI和EI收录的有60余篇。曾获国家科委颁布的国家科技成果1项,获省部级科技进步奖2项。第七次(2000年)和第八次(2002年)全国高分子液晶态学术会议任学术委员会委员。任全国甲壳素专家委员会成员。编著有《高分子材料实用剖析技术》(中国石化出版社)(1997.9)、《高分子分析手册》(中国石化出版社)(2004.5)。从事“高分子物理”和“高分子研究方法”等教学近二十年。主讲的“材料化学导论”课程2003年获福建省“精品课程”。现任教育部高分子材料与工程教学分指导委员会委员。担任厦门市同安区人民政府科技顾问团顾问。Macromolecules、J.Appl.Polym.Sci.、Macromolecules Bioscience、中国科学、高等学校化学学报、化学学报、高分子学报和应用化学等十几种国内外学术期刊的通讯评审人。
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成果数
10
【期刊论文】Studies on Glass Transition Temperature of Chitosan with Four Techniques
董炎明, Yanming Dong, Yonghong Ruan, Huiwu Wang, Yaging Zhao, Danxia Bi
Journal of Applied Polymer Science, Vol. 93, 1553-1558 (2004),-0001,():
-1年11月30日
Published online in Wiley InterScience (www.interscience.wiley.com). ABSTRACT: Studies on the glass transition temperature (Tg) of chitosan are difficult to pursue because of the difficulty in sample preparation and the hydroscopicity of samples. There are a few works concerning this principal relaxation of chitosan. Among them, several quite different values (150℃, 161℃, and 203℃) have been reported. In this paper, the Tg of chitosan (140~150℃) was determined by means of four techniques, namely, dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), thermally simulated current spectroscopy (TSC), and dilatometry (DIL). DSC measurement has been assumed not to be sensitive enough to detect the relaxation temperature of polysaccharides. We propose a new method to improve the sensitivity of the DSC measurement. After a physical aging treatment of samples, the transition in DSC traces became much more distinct because of the enthalpy relaxation. This technique was also used to distinguish the Tg from other relaxations. The Tg of chitosan with different degree of deacetylation (D.D.) was examined by DSC. No influence of D.D. on Tg was found.
chitosan, glass transition, ageing, DSC
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【期刊论文】Liquid crystalline behaviour of chitooligosaccharides
董炎明, Yanming Dong a, *, Huiwu Wang a, Weiya Zheng a, Yaqing Zhao a, Danxia Bi a, Lianjun Zhao b, Xingfu Li b
Carbohydrate Polymers xx(0000)xxx-xxx,-0001,():
-1年11月30日
Two chitooligosaccharide samples (COS1 and COS2) were prepared by enzymatic degradation of chitosan. The molecular weight of the main component was determined by mass spectrometry to be 2340 and 4303, respectively. They showed cholesteric liquid crystal structures in concentrated solutions. The critical concentrations to form a lyotropic liquid crystalline phase in formic acid were measured by means of polarized optical microscopy, refractometry and Fourier transform infrared spectroscopy. The results from the three methods agreed with each other. The experimental value of COS2 was quantitatively consistent with that calculated according to Khokhlov and Semenov theory. But the experimental value of COS1 diverged from the theoretical one, which is explained by the inaccuracy at higher concentrations of the second virial approximation underlying this theory.
Chitosan, Chitooligosaccharides, Liquid crystals, Critical concentration, Molecular weight
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【期刊论文】甲壳素类液晶高分子的研究Ⅷ1N-邻苯二甲酰化壳聚糖PDMSO液晶溶液的热致相转变*
董炎明, 吴玉松, 阮永红, 赵雅青, 王惠武, 周花
高分子学报,2003,(5)714~717,-0001,():
-1年11月30日
合成了氮上完全取代的邻苯二甲酰化壳聚糖(PhthCS)。用DSC研究了PhthCSPDMSO液晶溶液的热致相转变。偏光显微镜和DSC测定都表明临界浓度为43wt%。在浓度高于43wt%的溶液的DSC曲线中观察到了除了液晶-各向同性液体转变(清亮点)外还有一个明显的凝胶-溶胶转变,凝胶-溶胶转变温度和转变焓均比文献报道的不规则取代的N-邻苯二甲酰化-O-乙酰化壳聚糖大得多,可见取代的规整性对凝胶-溶较转变有很大的影响。根据DSC研究结果绘制了PhthCSPDMSO体系的相图。
SC,, 壳聚糖,, N-邻苯二甲酰化壳聚糖,, 溶致液晶,, 热致相转变,, 清亮点,, 凝胶-溶胶转变
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董炎明, Yanming Dong, *, Yusong Wu, Yaqing Zhao, Huiwu Wang, Yonghong Ruan, Hui Zhang, Xueming Fang
Carbohydrate Research 338(2003)1699-1705,-0001,():
-1年11月30日
The influence of concentration on the helicoidal change of N-phthaloylchitosan (PhCh) solutions in Me2SO, DMAc and DMF was investigated by means of circular dichroism (CD). The critical concentrations to form liquid crystal phase in these three solvents were 43, 45 and 48wt%, respectively as measured with polarized optical microscope. There were two kinds of CD peaks, sharp peaks with absorption maximum at about 330nm induced by the helical conformation of molecular chain, and very broad peaks covering almost whole visible region induced by the cholesteric helix of mesophase. The later only appeared in concentrated solutions with the concentration higher than the critical concentration. The handedness of both levels of helicoidal structures changed from left-to right-handed with the increase of concentration for PhCh/Me2SO solutions. The chirality transfer occurred between these two chiral levels. For PhCh/DMAc and PhCh/DMF systems, only the handedness of helical conformation reversed, but the cholesteric helix did not change. As a method to measure critical concentration, CD is more sensitive than polarized optical microscopy (POM).
N-Phthaloylchitosan, Cholesteric liquid crystals, Circular dichroism, Handedness, Conformation
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【期刊论文】Spherulite Morphology Studies of N-Alkyl Chitosan Films Cast from Formic Acid Solutions
董炎明, YANMING DONG, , KENSUKE SAKURAL, YUSONG WU, YUKIE KONDO
Jouraal of Polymer Science: Part B: Polymer Physics, Vol. 41, 2033-2038 (2003),-0001,():
-1年11月30日
ia evaporation procss. The crystalline morphology of these films was investigated by means of ploarized optical microscopy and scanning electron microscopy. Normal spherulites with a low growth rate formed in the casting films. The different morphologies of spherulite appeared in the filims cast from the solutins with diiferent concentration. After further crystallizing for a few days, the spherulites were decorated by thousands of needlelike extended-chain crystals, which had a typical size of ~50μm(length)×2~5μm(lenght)×1~2μm(width)×1~2μm(height) in the fringe part of the spherulite. The real concentration for crystallization was dedtermined solution.
chitosan, film, crystal, morphology, spheulites
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董炎明, Yusong Wu, *, Yanming Dong, Hua Zhou, Yonghong Ruan, Huiwu Wang, Yaqing Zhao
Journal of Applied Polymer Science, Vol. 90, 583-586 (2003),-0001,():
-1年11月30日
A selectively side-modified chitosan derivative, N-phthaloyl chitosan (PhthCs), was prepared. Five techniques, including circular dichroism (CD) spectropolarimetry, ultraviolet-visible (UV-vis) spectroscopy, small-angle light scattering (SALS), polarized optical microscopy (POM), and differential scanning calorimetry (DSC), were simultaneously applied to investigate the order-disorder phase transition for the lyotropic PhthCs/dimethyl sulfoxide system. POM observations suggested that the critical concentration was 48w%, which agreed well with the DSC measurements. A four-leaf SALS picture was recorded in biphasic solutions. The four-leaf type became a circular symmetric scattering picture with a further increase in the concentration. A sharp peak at 330 nm was recorded in dilute isotropic solutions with CD measurements. The sharp peak turned into a broad tailed peak from 330 to 800nm after the phase transition occurred. The sharp peak was induced by a chromophore (phthoyl group). The broad peak was attributed to the formation of short-range-ordered organization in the concentrated solutions. In UV-vis studies, when the system varied from isotropic to anisotropic, the absorption band turned into platform. These five techniques were proven to be feasible methods for measuring the phase transition of cholesteric liquid crystals.
UV-vis spectroscopy, differential scanning calorimetry (, DSC), , solution properties
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【期刊论文】Multiple crystalline morphologies of N-Alkyl chitosan solution cast films
董炎明, Yanming Dong, Kensuke Sakurai, Yusong Wu, and Yukie Kondo
Polymer Bulletin 49, 189-195 (2002),-0001,():
-1年11月30日
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【期刊论文】Studies on Lyotropic Liquid-Crystalline N-Alkyl Chitosans in Formic Acid
董炎明, Yusong Wu, Yanming Dong, *, Ling Chen, Jianying Huang, Jun Li
Macromol. Biosci. 2002, 2, 131-134,-0001,():
-1年11月30日
biopolymers, chitosan, critical concentration, degree of substitution, liquid-crystalline polymers (, LCP), , lyotropic
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董炎明, Yanming Dong, Congyi Xu, Jianwei Wang, Yusong Wu, Yonghong Ruan, Mian Wang
Polymer Bulletin 45, 495-500 (2001),-0001,():
-1年11月30日
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董炎明, Yanming Dong*, Yusong Wu, Jianwei Wang, Mian Wang
European Polymer Journal 37(2001)1713-1720,-0001,():
-1年11月30日
Hydroxypropyl chitosan (HPCS) with different degree of molar etherification (DME, from 0.6 to 6.0) were synthesized and characterized by FTIR, 1H-NMR and elemental analysis. The effect of DME on critical concentration forming lyotropic liquid crystal (C*) was investigated in three solvents (formic acid, dichloroacetic acid and water). C* increased as DME raised but presented a platform at low DME (less than about 2.6), which was explained based on both the amount and the size of flexible substituents. HPCS with DME ≥3.2 were water soluble. C* of HPCS aqueous solutions were evidently lower than those of formic acid or dichloroacetic acid solutions. Typical cholesteric texture appeared in HPCS solutions of all three solvents at proper concentrations.
Chitosan, Hydroxypropyl chitosan, Lyotropic liquid crystal, Degree of molar etherification, Critical concentration, Cholesteric texture
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