首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 95 毫秒
1.
研究以通用高分子聚己内酰胺(PA-6)及聚对苯二甲酸乙二醇酯(PET)为基质材料,用连续气相聚合的方法,使聚吡咯与之复合,可得到聚吡咯/PA-6(PPy/PA-6)及聚吡咯/聚对苯二甲酸乙二醇酯(PPy/PET)导电复合纤维,电导率最高可达10-1S/cm,力学性能有所下降。  相似文献   

2.
利用热分析研究了聚对苯二甲酸乙二醇酯(PET)与对苯二甲酸乙二醇酯(ET)-己内酯(CL)共聚物(TCL)共混体系的相容性,同时考察了体系中TCL组成分布不均一性及高温热处理对体系相容性的影响。  相似文献   

3.
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   

4.
采用DCS、POM、SEM及力学性能测试,研究了不同对羟基苯甲醛和对苯二甲酸乙二醇酯含量的液晶共聚酯PET40/PHB60(LCP1)和PET30/PHB70(LCP2)的共混物与尼龙1010为基体的三元混体系。结果表明,液晶共混物的力学性能比单组分有明显提高,通过改变混合液晶中两组分的含量可调节其加工温度与粘度,从而满足了与尼龙1010共混的加工窗口要求。混合液晶的加入对尼龙1010的结晶与熔融  相似文献   

5.
综述了用于聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)化学扩链反应的羧基加成型和羟基加成型扩链剂,以及缩合型扩链反应、羧基加成型扩链反应和羟基加成型扩链反应、羧羟基同时加成型扩链反应。讨论了扩链反应、反应特性和扩链产物的性能,并简要介绍了国内研究概况。参考文献20篇。  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.
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.
聚丙烯/聚对苯二甲酸乙二酯共混自增强材料的研究   总被引:5,自引:0,他引:5  
聚丙烯/聚对苯二甲酸乙二酯共混自增强材料的研究陈鸣才,黄玉惠,赵树录,廖兵,林果,丛广民(中国科学院广州化学研究所广州510650)关键词聚丙烯,聚对苯二甲酸乙二酯,高分子共混物,自增强材料聚对苯二甲酸乙二酯(PET)具有良好的成纤性和透明性,但收缩...  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.
用差示扫描量热法对聚对苯二甲酸乙二酯(PET)/热致液晶高分子(LCP)共混体系的等温和非等温结晶行为进行了研究.结果表明,由于液晶组分的加入,共混体系中PET的结晶速率和结晶度均得到提高.说明LCP具有PET结晶成核剂的作用.在较低的LCP组分含量下(~2wt%),这一效果最为明显,说明LCP是以很小的微区或某些LCP分子链介晶微束的形式对PET的结晶起成核剂的作用.  相似文献   

11.
用广角X-角线衍射法和差法扫描量热法研究了磷酸三苯酯对PBT/PET共混体系结晶行为影响,结果表明:TPPW作为该共混体系的稳定剂,只能延长在熔融状态下酯交换反应发生的时间,TPP含量一定时,熔融时间增加,PBT,PET之间的酯交换反应同样会发生,不同熔融时间,就要求TPP的用量也不相同。TPP在PBT/PET共混体系中没有结晶成核剂的作用,它也不改变PBT,PET的结晶结构。  相似文献   

12.
The blends of poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT) undergo transesterification reactions between PET and PBT during melt processing. In this research, PET/PBT transesterification has been investigated in the presence of nano-fillers, including pure SiO2 and silane-coupling-agent-modified SiO2. The results show that the incorporation of SiO2 nanoparticles inhibits PET/PBT transesterification, and the influence of pure SiO2 is higher than modified SiO2. The inhibition of SiO2 on transesterification is explained by the fact that the hydroxyl end groups of PET and PBT react with the surface hydroxyl groups of SiO2 before transesterification due to the high activity of surface hydroxyl groups of SiO2, and the reduction of hydroxyl end groups of PET and PBT leads to the inhibition of transesterification between PET and PBT. This has been demonstrated by the experimental data of TGA, FTIR, and XPS. And the reactivity of hydroxyl end groups of PBT is higher than that of PET.  相似文献   

13.
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   

14.
The occurrence of ester-interchange reactions during PET/PBT blend processing has been confirmed by 13C-NMR measurements. The limitations of the method for precise quantification of the extent of reaction between high molecular weight polyester blends have also been pointed out. Titanium alkoxide has been confirmed as an efficient catalyst, and, within experimental precision, the stabilizing effect of triphenyl phosphite addition has been demonstrated. © 1996 John Wiley & Sons, Inc.  相似文献   

15.
With the help of differential scanning calorimetry, cone-plate and capillary rheometry andscanning electron microscopy, a research has been conducted on rheological behavior,crystallization and morphology of poly (butylene terephthalate) (PBT) blends containing athermotropic LCP. The blend has zero entrance pressure loss, although the LCP has rather largeone. The viscosity curve of the blend lies between those of the LCP and PBT. The crystallizationof PBT is not affected by the presence of the LCP together with no indication oftransesterification between the two ingredients. LCP spheres and ellipsoids with the size of 0. 5--1. 5 μm disperse in PBT matrix uniformly, which is related to the viscosity ratio of the twocomponents.  相似文献   

16.
The concept of the drawing of a molecular network has been employed to derive a total network draw ratio from the combination of the two deformations occurring in the production of poly(butylene terephthalate), PBT, fibers by the consecutive processes of melt spinning and cold drawing. The mechanical properties of PBT can then be more readily explained in terms of increases in this total network draw ratio. However, the preorientation and crystallization that occurs in the melt-spinning process can occur at different strain rates and temperatures, depending on the wind up speed employed, on the extensional viscosity of the polymer, and on the variation of the extensional viscosity with temperature. Therefore, for polymers such as poly(butylene terephthalate), which can exist in two crystalline forms, the morphology of the final drawn fiber might be expected to depend on the first melt-spinning stage of the process as well as on the total network draw ratio. In this work, density, birefringence, mechanical measurements, and WAXD measurements, which have been made on the melt-spun fibers and on the drawn fibers, are described. Small differences in some of the drawn yarn mechanical properties at the same overall network draw ratio are related to the crystallinity and in particular to differences in the proportion of the α and β phases present in the drawn yarn. These in turn are related to differences in the temperature and stress during melt spinning and drawing. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35 : 2465–2481, 1997  相似文献   

17.
采用Instron3211型毛细管流变仪研究了PEA/PET共混物的流变性能,据此探讨共混物熔体的可纺性,讨论了共混物配比与复合纤维力学性能的关系,并且偏光显微镜,扫描电镜研究纤维的结构。结果表明,共混物的表观粘度低于PET的粘度,当PEA为10%,共混物的表观粘度达到最小值;且PEA含量低于10%时,共混物的可纺性即,表现出良好的原位增强效果。  相似文献   

18.
Poly(ethylene terephthalate)‐g‐methacrylamide (PET‐g‐MAAm) copolymer was prepared by graft copolymerization in organic solvent/water mixtures by using azobisizobutyronitrile (AIBN) as an initiator. The highest graft yield was obtained in 20/80 (v/v) acetonitrile/water mixture as 30.0%. The effect of polymerization parameters such as the ratio of solvent/water mixture, concentrations of initiator and monomer, temperature and time on the graft yield was studied. The moisture regain of the PET fiber increased with grafting from 0.42% to 3.01%. Thermogravimetric data showed that the thermal stability of PET fibers decreased with grafting and 85% of total weight of 29.7% grafted fiber was lost at 500°C. On the other hand, fiber density decreased with increasing graft yield. At SEM micrographs, the layers oriented in the direction of fiber length were observed on the surface of PET fiber as a result of grafting.  相似文献   

19.
Poly(butylene terephthalate) (PBT)/polycarbonate (PC) samples, prepared via reactive blending in the presence of Ti‐ and Sm‐based catalysts, resulted in block copolymers whose block length decreased as the mixing time increased. A single homogeneous amorphous phase occurred when the blocks had monomeric sequences shorter than 10 units. Otherwise, a crystalline phase of PBT developed. Also, in poly(ethylene terephthalate) (PET)/PC blends previously studied, the miscibility was strictly correlated with the crystallizability of the system. Therefore, the miscibility of the PBT/PC and PET/PC blends was compared with respect to the tendency of the PBT and PET blocks to crystallize under isothermal conditions. The crystallization rate of the PBT/PC copolymers was faster than that of the PET/PC copolymers with similar block lengths. Accordingly, the minimum crystallizable sequence length of the PBT blocks was shorter than that of the PET blocks (18 vs 31 monomeric unit sequences). This behavior was interpreted as an effect of the more flexible PBT units, which had a greater tendency to fold and crystallize than the PET units. Therefore, PBT, the blocks of which tended to crystallize even if they were very short and phase‐separated, was characterized by a poorer compatibility with PC than that of PET. As a result, the block size had a fundamental role in determining the crystallizability and, therefore, phase behavior of the semicrystalline block copolymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2821–2832, 2004  相似文献   

20.
The crystallization behavior of iPP in composites with PET, Nylon-6 and its own fibers under various conditions was studied using an optical microscope equipped with a hot stage. The results show that the nucleation capacity of PET and Nylon-6 fibers towards the iPP matrix is mainly controlled by the shear flow of the iPP matrix during sample preparation. When the composites were prepared at a temperature where the iPP was kept in its supercooled state, the nucleation of iPP on the PET and Nylon-6 fiber surfaces was enhanced due to the shearing of the iPP melts caused by introduction of the fibers. The nucleation was markedly reduced by keeping the composites at the fiber introduction temperature for a short time to relax the shear flow of the iPP matrix. The nucleation of iPP on its own fiber, however, is mainly related to the nature of the iPP fiber itself. No detectable morphological change of iPP on its own fiber can be identified under all thermal conditions used in this study.  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