首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 265 毫秒
1.
聚酯酰胺的合成及表征   总被引:1,自引:0,他引:1  
用两种方法合成了聚酯酰胺(PEA)共聚物.一种是两步法,即先合成对苯二甲酸乙醇酰胺(BAET)单体,然后与对苯二甲酸乙二酯(BHET)共缩聚;另一种是一步法.即在酯交换反应中直接添加乙醇胺(EA).两种方法制得的聚酯酰胺(PEA)共聚物测试证明了为产物,并分析了合成中的化学反应.  相似文献   

2.
研究了对象基苯甲酸(ABA)/聚对苯二甲酸乙二酯(PET)液晶共聚酯酰胺的晶体结构,以及热性能、流变学和力学性质。广角X射线衍射研究结果表明ABA链节的引入使PET的晶态结构发生畸变,但大部分结晶衍射峰仍然存在。随着ABA含量的增加,各晶面间距基本不变,微晶尺寸显著增大,结晶度急剧降低。差示扫描量热分析和热失重结果表明共聚酯胺具有优良的热稳定性,并且随着ABA含量的增加,共聚物的热稳定性提高,共聚  相似文献   

3.
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   

4.
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   

5.
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   

6.
本文研究工作表明,聚乙二醇(PEG)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.而且使成核剂的成核效率提高,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,而用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%时的模量及γ-衰减强度最大.动态力学性能最好.  相似文献   

7.
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   

8.
液晶嵌段共聚物PET/60PHB-b-PC的合成及结构与性能   总被引:1,自引:0,他引:1  
采用PET齐聚物的原位乙酰化法通过加入少量乙二醇(EG)合成了端羟基液晶聚合物PET/60PHB,并将其作为大单体,与双酚A及碳酸二苯酯通过熔融酯交换法,进一步制得了液晶嵌段共聚物PET/60PHB b PC.研究了合成规律,并借助粘度测定、DSC、偏光显微镜、X 光衍射和红外光谱分析等手段对合成的液晶嵌段共聚物进行了表征.研究表明,当PET齐聚物的ηinh=005~007dL/g,Ac2O/PHB(mol/mol)=13,EG/PET(mol/mol)=006时能获得颜色、液晶性、溶解性均很好的端羟基液晶聚合物PET/60PHB,以此液晶聚合物为原料,采用合适的配方与工艺,能获得粘度较高、液晶性较好,并且熔体流动性很好的液晶嵌段共聚物PET/60PHB b PC.通过偏光显微镜与X 光衍射观察,证明此嵌段共聚物呈现向列型液晶织构,但其液晶态织构与纯PET/60PHB、PET/60PHB和PC的混合物明显不同.此外,还初步建立了用红外的分析手段鉴定液晶聚合物PET/60PHB端基的方法.  相似文献   

9.
对羟基苯甲酸与对苯二甲酸乙二酯的共聚物研究张广利,阎丰琪,李勇,王震,潘景岐,张鸿志(北京大学化学系北京100871)关键词液晶共聚酯,PET/PHB共聚脂,序列分布Jacbon和KuhfuJ’l于70年代报道了对羟基苯甲酸(PHB)一对苯二甲酸乙二...  相似文献   

10.
聚丙烯酸酯无皂水溶胶阻尼涂料动态力学性能的研究   总被引:6,自引:0,他引:6  
用分步溶液聚合法合成了两种丙烯酸酯共聚物的共混物[P(BA-HEMA-AA)/P(MMA-HEMA-AA)A],制成无皂水溶胶,加入交联剂配成涂料。两种共聚物既可相互贯穿缠结,又可通过交联剂交联,使涂膜同时具有物理交联和化学交联。用动态力学分析法(DMA)、扭辫分析法(TBA)考察了涂膜的动态力学性能,表明涂膜具有IPN结构,并有良好的阻尼性能。  相似文献   

11.
A new class of poly(ester-imide-ether) multiblock copolymers was synthesized by transes-terification and meltcopolymerization of dimethyl terephthalate (DMT) and N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide withethylene glycol (EG) and polytetramethylene glycol (PTMG). The structure of the above copolymers was characterized by~1H-NMR and IR spectroscopy. Some properties of the coplymers were also examined. It was found that their mechanicalproperties and heat stability, compared with poly(ether-ester) copolymers, were obviously improved.  相似文献   

12.

Zinc salicylaldimine complex immobilized on silica gel was used as a promising catalyst for the transesterification reaction of dimethyl terephthalate (DMT) and ethylene glycol (EG).The catalyst was characterized by Fourier transform infra‐red spectroscopy (FT‐IR), thermogravimetric analysis (TGA) and atomic absorption spectroscopy (AAS). The product bis‐(2‐hydroxyethyl)terephthalate (BHET)was confirmed by mass and 1H‐NMR studies. In comparison to zinc acetate i.e., homogeneous catalyst, a polymer supported catalyst showed better stability, catalytic activity and ease of separation from the reaction product. The catalyst can be reutilized during successive catalytic cycles.  相似文献   

13.
Catalytic activity of a metal complex for both the transesterification of DMT (dimethyl terephthalate) and the polycondensation of BHET (bis(2-hy-droxyethyl terephthalate)) is described in terms of an acidity function formulated from the physical properties of the metal ion. Catalytic activity for both reactions is governed by the acidity of the metal ion, not by the type of anionic ligand. Maximum catalytic activity is observed with optimum bond strength between the metal ion and the double-bonded oxygen in the ester carbonyl group of DMT or BHET. Thus, a basic (less acidic) metal ion exhibits high catalytic activity for a more basic oxygen in the ester carbonyl of DMT, while a more acidic metal ions exhibits high catalytic activity for a less basic oxygen in the ester carbonyl of BHET. in the polycondensation reaction, a semiconductor metal ion shows higher activity than an insulator metal ion when compared at the same acidity value, but the former also catalyzes side reactions which can cause discoloration of the final polyethylene terephthalate) polymer. Discoloration is enhanced when a semiconductor metal ion has a redox couple during polycondensation.  相似文献   

14.
配合超临界甲醇解聚聚对苯二甲酸乙二醇酯的工艺开发,采用高效液相色谱法对聚对苯二甲酸二乙酯的超临界甲醇解聚固体产物进行了分离、定性和定量分析。采用反相色谱体系,色谱柱为Zorbax-C8柱,流动相为甲醇-水(70/30,V/V),紫外检测器。该法具有高色谱分辨率、简便、准确、重复性好等特点。  相似文献   

15.
Summary: The tetrabutylorthotitanate (TBOT) was hydrolyzed by H2O produced during the esterification of pure terephthalic acid (PTA) and ethylene glycol (EG), and the bis(2-hydroxyethyl) terephthalate (BHET)/titanium compound nanocomposite was in-situ formed. The effect of TBOT on the esterification and its product property has been investigated. The results show that the butyl alcohol from the hydrolysis of TBOT is almost distilled out with H2O and there has no effect on the chemical structure of BHET caused by the introducing of TBOT. A kind of novel titanium compound is manufactured during the esterification under the existence of TBOT, which shows slice-like morphology from SEM micrographs and special XRD pattern with new diffraction peaks between 2-Θ = 6.9° and 10.2°. It is found that the BHET/titanium compound nanocomposite can act as the catalyst of polymerization of poly(ethylene terephthalate) (PET). The PET resins synthesized by in-situ formed catalyst have almost the same physicochemical properties with the commerced resins and have good spinnability.  相似文献   

16.
The kinetic analysis of the transesterification of ethylene glycol (EG) and dimethyl terephthalate (DMT) was studied in a semibatch reactor under nonisothermal conditions. The effect of the temperature profile, EG/DMT ratio, and catalyst concentration on the reaction rate was studied. Models were fitted by using an algorithm of parameter estimation in differential equations based on the Gauss–Newton method improved with the Marquardt extension. It was found that, unlike previous authors, the reaction rate was not a classical third order reaction of first order with respect to EG, DMT, and catalyst concentration, but the EG reaction order was 0.6 and a hyperbolic function was found to fit the relationship between reaction rate and catalyst concentration. Also, it was found that, at high conversions, the effect of the reverse reaction should not be neglected.  相似文献   

17.
Zhang C  Xu L  Zhang H  Yang J  Du J  Liu Z 《Journal of chromatography. A》2004,1055(1-2):115-121
A method based on high-resolution size-exclusion chromatography (SEC) was established to analyze the solid products from the depolymerization of poly(trimethylene terephthalate) (PTT) in supercritical methanol. In the qualitative analysis, four factors (chromatographic retention time, qualitative multi-wavelength ultraviolet spectra, linear internal-insert SEC and qualitative IR spectra) were considered. The main solid products from the process were dimethyl terephthalate (DMT), methyl-(2-hydroxypropyl) terephthalate (MHPT), bis(2-hydroxypropyl) terephthalate (BHPT), methyl-(2-hydroxyethyl) terephthalate (MHET), bis(2-hydroxyethyl) terephthalate (BHET), and hydroxyethyl-(2-hydroxypropyl) terephthalate (HEHPT). It is found that the method is of a high resolution among the solid products and has a fine repeatability. In addition, the solid products from the de-polymerization of poly(ethylene terephthalate) (PET) in similar process were also analyzed by this method. Furthermore, the effects of supercritical conditions on the distribution of the products were also discussed.  相似文献   

18.
硒芳香杂环化合物的微波固相合成   总被引:2,自引:2,他引:2  
许多含硒杂环化合物具有抗肿瘤、抗病毒等生物活性及超导性。微波技术由于能量利用率高,操作简便,无污染等优点,已在有机合成中得到了广泛的应用。本文采用微波辐射固相合成法合成了如下目标化合物:  相似文献   

19.
Poly(ethylene terephthalate) [PET] fibre wastes from an industrial manufacturer was depolymerised using excess ethylene glycol [EG] in the presence of metal acetate as a transesterification catalyst. The glycolysis reactions were carried out at the boiling point of ethylene glycol under nitrogen atmosphere up to 10 h. Influences of the reaction time, volume of EG, catalysts and their concentrations on the yield of the glycolysis products were investigated. The glycolysis products were analysed for hydroxyl and acid values and identified by different techniques, such as HPLC, 1H NMR and 13C NMR, mass spectra, and DSC. It was found that the glycolysis products consist mainly of bis(hydroxyethyl)terephthalate [BHET] monomer (>75%) which was effectively separated from dimer in quite pure crystalline form.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号