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1.
聚氨酯/环氧树脂互穿网络聚合物的性能研究   总被引:12,自引:0,他引:12  
互穿聚合物网络(Interpenetrating polymer net-work,简称IPN)广泛应用的为聚氨酯基的互穿网络聚合物。其合成多集中在弹性体方面。本文用同步法合成的聚氨酯/环氧树脂互穿网络硬质泡沫塑料材料(简称PU/ERIPNF),机械性能较好,并研究了其动态力学性能及形态变化。  相似文献   

2.
反应注射成型聚氨酯互穿聚合物网络的进展   总被引:2,自引:0,他引:2  
范连华  胡春圃 《高分子通报》1997,(3):129-134,143
本文将介绍有关反应注射成型聚氨酯同步互穿聚合物网络(RIM SIN)方面的研究工作。综合文献报道和我们研究扬实验工作,重点描述了不饱和聚酯树脂或乙烯基酯树脂为刚性相的聚氨酯互穿聚合物网络,讨论了它们的生成反应动力学及其形态结构发展进程,并与样品力学性能相关联。  相似文献   

3.
不饱和聚酯/聚氨酯互穿网络聚合物的合成   总被引:8,自引:1,他引:8  
以醋酸酐封端的不饱和聚酯(FUPR)与交联聚氨酯预聚物制备了具有互穿聚合物网络(IPN)的不饱和聚酯/聚氨酯,通过红外,DSC和扫描电镜等分析了FUPR/PUIPN网络形成的动力学,微相分离行为及力学性能,结果表明,当FUPR/PU达到某一比值时,产生网络互穿效应,可改善聚氨酯的刚性,提高不饱和聚酯的抗冲性。  相似文献   

4.
邻甲酚醛环氧树脂/聚氨酯互穿聚合物网络的形态与性能   总被引:1,自引:0,他引:1  
邻甲酚醛环氧树脂/聚氨酯互穿聚合物网络的形态与性能;互穿聚合物网络; 邻甲酚醛环氧树脂; 聚氨酯; 力学性能; 玻璃化转变温度  相似文献   

5.
聚氨酯互穿聚合物网络阻尼性能研究进展   总被引:18,自引:0,他引:18  
介绍了聚氨酯互穿聚合物网络(PU IPN)作为阻尼材料的研究进展,分别讨论了聚氨酯(PU)/环氧树脂(EP)IPN和PU/乙烯基聚合物IPN的阻尼性,以及影响阻尼性能的因素,并比较了不同类型的PU IPN的优缺点及新的可能的探讨方向。  相似文献   

6.
蓖麻油聚氨酯/聚甲基丙烯酸甲酯交联共聚物的溶胀刘和文,蔡宇东,施文芳,周永龙(中国科学技术大学应用化学系合肥230026)(广西分析测试研究中心南宁)关键词蓖麻油聚氨酯,聚甲基丙烯酸甲酯,交联共聚物,溶胀,相逆转互穿网络聚合物(IPN)的平衡溶胀度及...  相似文献   

7.
聚氨酯/乙烯基酯树脂互穿聚合物网络阻尼性能的研究   总被引:9,自引:0,他引:9  
采用二步法制备了聚氨酯/乙烯基酯树脂互穿聚合物网络,动态力学分析法研究了IPN的阻尼性能。结果表明,聚氨酯/乙烯基酯树脂互穿聚合物网络出现宽温度阻尼范围。当聚氨酯/乙烯基酯树脂=40/60时,材料的宽温度范围的阻尼性能最好。在体系中引入柔性链可改善低温阻尼性能,而引入刚性链则降低阻尼值、提高阻尼温度、阻尼温度范围变窄。在体系中引入大侧基能显著提高聚氨酯/乙烯基酯树脂互穿聚合物网络的阻尼性能,提高交  相似文献   

8.
用微型反应注射成型机制备了以聚氨酯(PU)为弹性相的两类同步互穿聚合物网络(SIN),其刚性相分别采用保留仲羟基的乙烯基酯树脂(VERH)以及封闭仲羟基的乙烯基酯树脂(VERA)。用傅里叶变换红外光谱在线跟踪了这类互穿网络的生成过程,发现刚性网络抑制了PUC网络中硬段有序结构的形成,两个网络间有一定程度的互穿,而两个网络间的化学键作用进一步削弱氢键强度。自旋-自旋驰豫时间的测定进一步表明网络间存在  相似文献   

9.
微波辐照合成互穿聚合物网络及形态性能研究   总被引:3,自引:0,他引:3  
微波辐照合成互穿聚合物网络及形态性能研究李卫华,王静媛,李跃先,刘福安,李玉玮,汤心颐(吉林大学化学系,长春,130023)关键词微波辐照,互穿聚合物网络(IPNs),形态性能互穿聚合物网络(IPNs),是一种新型的高分子复合材料,因具有独特的消声、...  相似文献   

10.
互穿网络聚合物;蓖麻油;聚氨酯;甲苯二异氰酸酯;热降解  相似文献   

11.
The present review gives the main advances made in the laboratory of alkaloid chemistry of the Institute of Plant Substances of the Usbekistan Republic Academy of Sciences [IKhRV AN RUz] (Tashkent) over 50 years in the field of the chemistry of diterpene, isoquinoline, quinoline, steroid, indole, spiropiperidine, sulfur-containing, tropane, pyrrolidine, quinazoline, quinolizidine, amaryllis, and pyrrolizidine bases and possible routes for the biosynthesis of some of these groups of alkaloids.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–33, January–February, 1993.  相似文献   

12.
Provenance and authenticity of wines can be recognized on the basis of typical mineral and trace element patterns by means of chemometric methods. Therefore analytical methods were developed for the determination of As, Be, Co, Cs, Ga, Li, Nb, Ni, Rb, Te, Ti, W, Y, and Zr as well as Mo, Cd, Sb, Tl, U, and the rare earth elements in wines by inductively coupled plasma mass spectrometry (ICP-MS). For low risk of contamination or loss of analyte as well as depletion of sample amount and an easy sample pretreatment, direct measurement of diluted wines was studied. The accuracy of the analytical results was proven by recovery experiments by method comparison with standard addition methods and measurement of digested wines. In addition to applying statistical methods for characterizing the precision of the methods, the uncertainty of the measurements was estimated.Results for the elements mentioned above and additional 16 elements (Al, B, Ba, Ca, Cr, Cu, Fe, Mn, Mg, P, Pb, Si, Sn, Sr, V, and Zn) were evaluated by data analytical methods. Due to a specific choice of the analytes for multivariate statistical investigation a prediction rate by cross validation of 88.6% could be achieved.  相似文献   

13.
采用硝酸、高氯酸进行消解,用ICP-AES对秦艽中的宏量和微量元素含量进行了测定,比较了不同施肥处理与不同生长年限处理对植株内宏量和微量元素的影响.结果表明,不同施肥及生长年限处理秦艽所含宏量和微量元素含量不同,不同施肥处理与CK相比,施NPK混合肥最好,能够增加Fe、Mn、zn、Na、Mg的含量,分别为18.5%、1...  相似文献   

14.
Literature information on the HPLC of alkaloids, including adsorption, reversed-phase, ion-exchange, ion-pair, and other variants is generalized. Results are given of the chromatographic analysis of various classes of alkaloids with an indication of the conditions of separation, and the columns used, and also of the methods of detection. The advantages and disadvantages of the HPLC variants are discussed. The review includes the literature over the last 14 years. Scientific Center for Chromatography, Institute of Chemistry and Physics of Polymers, Uzbek Academy of Sciences, Tashkent. Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 595–613, September–October, 1991.  相似文献   

15.
The potential of near-infrared spectroscopy (NIRS) for the quality control of traditional Chinese medicine has been evaluated. Seven quantitative parameters, andrographolide, deoxyandrographolide, dehydroandrographolide, neoandrographolide, moisture, ash content, and alcohol-soluble extract of Andrographis paniculata, were evaluated by NIRS. The reference values of andrographolides were determined by high-performance liquid chromatography, and the others were obtained using the standard methods of the 2015 Chinese Pharmacopoeia. The predicted values were determined by a quantitative model using NIRS based on partial least square regression. Different spectral preprocessing methods, spectral ranges, and optimum number of factors were selected to optimize the models. All models were estimated by the combination of various parameters, including the correlation coefficient of calibration for andrographolide, deoxyandrographolide, dehydroandrographolide, neoandrographolide, moisture, ash content, alcohol-soluble extract (values of 0.980, 0.984, 0.989, 0.983, 0.987, 0.988, 0.979, respectively), root mean square error of calibration (values of 0.156, 0.038, 0.050, 0.029, 0.604, 0.431, 0.135, respectively), root mean square error of prediction (values of 0.169, 0.041, 0.050, 0.033, 0.280, 0.493, 0.140, respectively), root mean square error of cross-validation (values of 0.626, 0.114, 0.158, 0.046, 1.145, 0.774, 0.508, respectively), and ratio of standard deviation to standard error of prediction (values of 4.583, 4.690, 4.796, 4.899, 4.899, 4.690, 5.099, respectively). The results show that the calibration models by NIRS are reliable and can be applied for the quantification for seven parameters from A. paniculata for quality control in traditional Chinese medicine production and processing.  相似文献   

16.
Summary A GC-MS procedure is described for the simultaneous quantitatation of the minor and major constituents of honeys, as their trimethylsilyl derivatives, from one solution, by one injection. Selected minor components (aliphatic and aromatic carboxylic acids, members of various homologous series, together with o-phosphoric acid, proline and hydroxymethylfurfurol), have been determined on the basis of their characteristic fragment ions, in the presence of extremely high excess of honeysaccharides. Selective fragmentation of these minor compounds in the ion trap detector provided possibilities for distinguishing them. The method permitted the simultaneous quantitation of o-phosphoric, malic, shikimic, citric/isocitric, quinic, margaric, oleic and stearic acids, hydroxymethylfurfurol and proline with the extremely high sugar contents of honeys (fructose, glucose, galacturonic acid, inositol, sucrose, trehalose, turanose, maltose, gentiobiose, isomaltose, raffinose, erlose, melezitose, maltotriose, panose, isomaltotriose) and allowed the fast evaluation of sugar and acid constituents of fifteen honeys from various floral and geological origin. Results revealed that (i) the minor components varied in the concentration range of 0.0001 to 0.43%, and, (ii) together with the saccharides of honeys made up the total of identified and determined constituents from 87.8% to 98.5%. Quantitative evaluation of the minor constituents was performed on the basis of their selective fragment ion values with an average reproducibility of 6.7% (RSD). Presented at: Balaton Symposium on High-Performance Separation Methods, Siófok, Hungary, September 3–5, 1997  相似文献   

17.
范苏娜  陈杰  顾张弘  姚响  张耀鹏 《高分子学报》2021,(1):29-46,I0003,I0001
随着环境污染、资源枯竭和医疗健康等问题的加剧,研发同时满足特定使用性能、安全性及可再生性的新型材料成为当前的发展趋势.而丝素蛋白材料正是以天然蚕丝为基本原材料,经一定的加工和功能化而形成的具有特殊结构、独特性能和广泛应用的生物质材料,近年来在生物医药、生物电子、智能传感等领域展现出巨大的应用潜力.本专论总结了丝素蛋白纤维及功能化材料的最新成果,结合本课题组相关工作,重点阐述了再生丝素蛋白纤维的仿生制备、生物医用支架的构筑与功能化、智能电子材料的设计以及天然多功能蚕丝及其构筑基元制备的研究进展,以期为高性能丝素蛋白材料的设计与构筑提供指导和借鉴.  相似文献   

18.
Institute of Inorganic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Institute of Catalysis, Siberian Branch, Academy of Sciences of the USSR. Institute of Chemistry and Chemical Technology, Siberian Branch, Academy of Sciences of the USSR. Branch of the Institute of Chemical Physics, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 29, No. 6, pp. 90–103, November–December, 1988.  相似文献   

19.
Wheat is one of the most grown crops in Saudi Arabia. It is grown in various regions of the country. Accurate knowledge of the elemental concentrations in wheat and its products (bran and flour) is of great importance from a nutritional point of view. Wheat samples were obtained from the Al-Qusim region, 300 km northwest of Riyadh, and analyzed. Up to 50 elements (Al, Sb, As, Ba, Br, Cd, Ca, Cs, Cl, Cr, Co, Cu, Ga, Au, Hf, In, I, Ir, Fe, Mg, Mn, Hg, Mo, Ni, K, Rb, Sc, Se, Ag, Na, Sr, Ta, Te, Th, Sn, Ti, W, U, V, Zn, Zr, Ce, Dy, Eu, La, Lu, Nd, Sm, Tb and Yb) were determined in the wheat products. It was observed that the elemental content of bran was much higher than that of white flour.  相似文献   

20.
The compositions of cottonseed soapstocks from first-grade and low-grade cotton seeds have been studied by the methods of CC on polyamide and on silica gel, TLC, GLC, ESR, and UV, IR, and mass spectrometry. It has been found that saturated, and also oxygenated, fatty acids, nonpolar acylglycerols, glycolipids, sterols, arylalkanes, gossypol pigments, and ions of metals of variable valence are concentrated in the acid fat of the soapstock from low-grade seeds. The soapstock contains a very small amount of tocopherols and phospholipids, mainly phosphatidylinositols. The combined gossypol pigments of the soapstocks include stabilized gossypol radical ions.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 502–508, July–August, 1988.  相似文献   

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