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1.
不同拉伸比PET/PBT共混纤维的热行为及力学性能   总被引:1,自引:0,他引:1  
尹秀丽 《应用化学》1995,12(3):111-112
不同拉伸比PET/PBT共混纤维的热行为及力学性能尹秀丽(天津纺织工学院材料科学系天津300160)关键词聚对苯二甲酸乙二醇酯,聚对苯二甲酸丁二醇酯,共混纤维,热行为,力学性能不同配比聚对苯二甲酸乙二醇酯(PET)/聚对苯二甲酸丁二醇酯(PBT)共混...  相似文献   

2.
酞侧基聚芳醚砜/对苯二甲酸乙二酯-对羟基苯甲酸嵌段共聚物共混物的研究李刚,殷敬华,李滨耀(中国科学院长春应用化学研究所,长春,130022)关键词酞侧基聚芳醚砜,热致性液晶高聚物,原位复合材料,对苯二甲酸乙二酯-对羟基苯甲酸嵌段共聚物将热塑性树脂与热...  相似文献   

3.
取向聚对苯二甲酸乙二酯纤维的非等温结晶动力学张志英,赵家森(天津纺织工学院材料科学系天津300160)关键词取向高聚物,聚对苯二甲酸乙二酯,非等温结晶,结晶动力学研究高聚物结晶动力学常用的等温方法有光透射法、密度法、显微镜法、X-射线衍射法、差示扫描...  相似文献   

4.
双唑啉化合物偶联聚酯的研究Ⅰ.双唑啉化合物的合成及其性能*陈玉君杨始方方土游飞越潘鉴元(中山大学高分子研究所广州510275)关键词双唑啉,扩链剂,聚酯聚酯,包括聚对苯二甲酸乙二酯(PET)和聚对苯二甲酸丁二酯(PBT)等的高性能化,要求提高其...  相似文献   

5.
研究了聚对苯二甲酸丁二酯(PBT)/聚对苯二甲酸乙二酯(PET)共混物的固态缩聚反应,从反应动力学过程的测定结果,表明与纯PET或PBT不同,其反应速度较快,并呈超加和的相对分子质量(以特性粘数[η]表征)增长。从反应发生在液相的基本观点出发,说明温度、共混等使液相增多,将加速反应的进行,加上共混物之间的相互缩聚和酯交换,生成嵌段共聚物的结果,导致超加和效应。  相似文献   

6.
采用不同的共混方式-溶液法,熔融法I(简单机械共混)和熔融法Ⅱ(存在酯-酰胺交换反应)将聚对苯二甲酸乙二酯与聚酰胺66共混,研究了共混体的形态结构和流变性能,探讨了对甲苯磺酸催化下的酯-酰胺交换反应和PET/PA66共混体系的相容性。  相似文献   

7.
采用不同的共混方式-溶液法、熔融法Ⅰ(简单机械共混)和熔融法Ⅱ(存在酯-酰胺交换反应)将聚对苯二甲酸乙二酯(PET)与聚酰胺66(PA66)共混,研究了共混体的形态结构和流变性能,探讨了对甲苯磺酸(TsOH)催化下的酯-酰胺交换反应和PET/PA66共混体系的相容性.  相似文献   

8.
三元乙丙橡胶环氧化增韧聚对苯二甲酸丁二酯的研究   总被引:1,自引:0,他引:1  
三元乙丙橡胶环氧化增韧聚对苯二甲酸丁二酯的研究王学会,张会轩,王新华,王志刚,蒋俊光,姜炳政(吉林工学院化工系,长春,130012)(中国科学院长春应用化学研究所)关键词三元乙丙橡胶,环氧化,PBT,增韧作用,共混物聚对苯二甲酸丁二酯(PBT)具有优...  相似文献   

9.
本文研究工作表明,聚乙二醇作为聚对苯二甲酸乙二酯(PET)/聚对苯二甲酸丁二酯(PBT)共混体系的结晶促进剂,不仅使聚合物分子链运动容易而有利于结晶时定向排列,晶体生成速度加快,而且使成核的成效率提高,晶核生成速度加快,晶核数目增多而晶体尺寸减小,此外,PEG还部分参与了聚酯的酯交换反应,在低用量时有利于聚合物特性粘数提高,而且量增大则引起聚酯降解。由于PEG的这些作用,共混体系在PEG为6.0%  相似文献   

10.
大区域取向对非晶态聚对苯二甲酸乙二酯结晶的影响林辛,吴永升,高金贵,范庆荣(中国科学院化学研究所北京100080)关键词聚对苯二甲酸乙二酯,溶剂诱导结晶,大区域取向Slonimsky等’‘’“最早注意到区分小区域取向和大区域取向的概念,钱人元等”’对...  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

17.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

18.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

19.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

20.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

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