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1.
研究了从端乙酰氧基聚醚代替端羟基聚醚合成聚对苯二甲酸乙二酯-聚四亚甲基醚多嵌段共聚物的新途径。探讨了其嵌段共聚合反应过程。所合成的嵌段共聚物是性能优良的热塑弹性体。  相似文献   

2.
嵌段液晶高聚物对聚醚砜 聚对苯二甲酸乙二醇酯/聚对羟基苯甲酸共混物的增容作用张海良张雪飞王霞瑜(湘潭大学化学化工学院湘潭411105)关键词增容作用,嵌段共聚物,原位复合材料基于热致性液晶高分子(TLCP)的原位复合材料以其高性能及易加工等特点而得...  相似文献   

3.
聚酯醚共聚物中PEG嵌段的储能行为   总被引:1,自引:0,他引:1  
采用重均分子量为1000-4000的聚乙二醇、对苯二甲酸二甲酯和乙二醇为原料合成了聚醚含量在40-60%(重量)的聚对苯二甲酸乙二酯-聚乙二醇共聚物,采用差热分析和宽角×射线衍射的方法,研究了共 聚物中聚乙二醇嵌段的储能行为,探讨了采用取醚嵌段可结晶的聚酯醚为原料熔融纺丝研制具有蓄热调温功能纤维的可能性。  相似文献   

4.
本文通过红外光谱、DSC和电镜等手段阐明了聚对苯二甲酸乙二酯-聚四亚甲基醚多嵌段共聚物的聚集态结构,特别是采用核磁共振法测定了嵌段比例和序列分布。  相似文献   

5.
通过原位直接缩聚反应,制备了刚性棒状聚对羟基苯甲酸酯和聚对苯二甲酸丁二醇酯-聚四亚甲基醚多嵌段共聚物和微相复合物,复合物可溶于氯仿等溶剂,可以浇铸成膜,本文研究了PHB含量和聚合过程中,基体聚合物溶液浓度对微相复合物形态以及力学性能影响,同共混法相比,原位缩聚法可得到分散更均匀,力学性能更优良的微相复合物。  相似文献   

6.
酞侧基聚芳醚酮的热学性能谢红卫,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酮,pvT行为,导热系数,定压比热容酞侧基聚芳醚酮(PEK-C)具有较高的玻璃化转变温度,其流变加工性能和力学性能已被广泛研究[1~3],被证明是...  相似文献   

7.
多嵌段聚醚-酯共混物的微相结构与血液相容性研究   总被引:3,自引:0,他引:3  
本工作合成了两种性质不同的聚醚-酯多嵌段共聚物,一种是以聚对苯二甲酸乙二酯为硬链段,聚乙二醇(PEGT)为软链段的亲水性多嵌段共聚物,另一种是以聚对苯二甲酸乙二酯为硬链段,聚四亚甲基醚二醇(PTMGT)为软链段的疏水性多嵌段共聚物。将两种共聚物以一定的比例共混,制备多嵌段聚醚-酯共混物。 改变共混物的组成,研究其微相结构与血液相容性的关系。采用动态力学谱(VES)、示差扫描量热(DSC)、透射电镜(TEM)和扫描电镜(SEM)等测定共混物的微观结构,采用微球柱法评价共混物的血液相容性。实验结果表明:材料的微观非均相结构及亲水平衡是决定血液相容性的重要因素。  相似文献   

8.
通过原位直接缩聚反应,制备了刚性棒状聚对羟基苯甲酸酯(PHB)和聚对苯二甲酸丁二醇酯-聚四亚甲基醚多嵌段共聚物(PBT-PTMG)的微相复合物.复合物可溶于氯仿等溶剂,可以浇铸成膜.本文研究了PHB含量和聚合过程中,基体聚合物溶液浓度对微相复合物形态以及力学性能影响.同共混法相比,原位缩聚法可得到分散更均匀,力学性能更优良的微相复合物.  相似文献   

9.
合成了不同软锻段长度和不同链段含量的系列对苯二甲酸乙二酯-环氧乙烷(PET-PEO)多嵌段共聚物,用NMR质子谱测定了硬链段一,对部分溶于氯仿的PET-PEO多嵌段共聚物进行了分离,并分别测定基氯仿可溶物和不溶物的硬边段一、熔融热谱和热结晶谱,揭示了PET-PEO多嵌段共聚物的组成不均一性及其对软段长度和硬链段一的信赖性,进而用DSC热谱证明了软链段和硬链段的结晶能力与PET-PEO多嵌段共聚物组  相似文献   

10.
高硬段含量和高软段分子量的聚酯-聚醚多嵌段共聚物有明显的组成不均一性,可分离出大量高熔点的氯仿不溶组份.通过和5mol%间苯二甲酸二甲酯(DMI)共聚,可改进其表观组成均一性,得到不含氯仿不溶物和力学性能优良的硬段含量为40wt%、软段分子量为4000的聚对苯二甲酸乙二酯-聚乙醇醚多嵌段共聚物(PET-PEG).另一合成途径是以间苯二甲酸(IPA)酸解 PET,再和端羟基聚乙二醇醚共缩聚,也可制得相应的改性 PET-PEG.降低聚醚分子量可以有效地改进其组成均一性.  相似文献   

11.
The blends of phenolphthalein Polyethersulfone (PES - C ) and a thermotropic liquid crystalline polymer (LCP ) were prepared using melting mixing method.Rheological and mechanical properties of the blends were investigated. It was shown that addition of LCP in PES-C resulted in marked reduction of melt viscosity and improved processibility. The Chadly impact strength of the blend containing 2. 5% LCP increased about 2. 5 times comparing with pure PES-C. The tensile strength, Young's modulus, fie-cural strength and flexural modulus of the PES-C/LCP blends were also improved on some extent. The morphology of these blends were also observed by SEM,and the relationship between the me-chanical properties and the morphology of blends were discussed.  相似文献   

12.
热致液晶PEI与PES—C共混物的研究   总被引:2,自引:0,他引:2  
通过熔融共混,制备不同配比(2.5/97.5-75/25)的PEI/PES-C共混物,使用WAXD、DSC、锥板流变仪、力学性能测试、SEM等方法对共混物进行了研究。共混后强度、模量均有提高,在高剪切速率下,共混物的粘度有所降低。扫描电镜照片显示,共混物具有“皮芯”结构。  相似文献   

13.
采用溶液共混制备耻不同比例的热致液晶共聚酯/含酚酞侧基聚芳醚砜共混物。利用锥板流变仪对共混体系的熔体流变性能进行了初步研究,测定了熔体粘度-温度、粘度-剪切速度的关系,结果表明该液晶聚合物能明显降低聚芳醚砜的熔体粘度。  相似文献   

14.
Abstract

Polyester elastomer (PEL) blends having a hard segment of polyester (PBT), soft segment of polyether (PTMG), and a liquid crystalline copolyester (LCP), poly(benzoate-naphthoate) were prepared with a twin-screw extruder. Test specimens for thermal properties were prepared by injection molding. Rheological properties and morphology were investigated by Instron capillary rheometer (ICR) and scanning electron microscopy (SEM). Thermal properties of the LCP/PEL blends were investigated by DSC, dilatometer, heat deflection temperature tester, and a Rheovibron viscometer. DSC study revealed a partial miscibility between LCP and PEL. It was found that the LCP acted as a nucleating agent for the crystallization of PEL in the LCP/PEL blends. The dimensional and thermal stability of the blends were increased by increasing the LCP cont-ent. The storage modulus (E' was improved by increasing the LCP content. The blend viscosity showed a minimum value at 5 wt% of LCP which increased by increasing the LCP content above 5 wt% of LCP The morphology of the LCP/PEL blends showed poor interfacial adhesion between the two phases, and the fibrillar structure of LCP phase in the matrix was affected by the LCP content, shear rate, and extrusion temperature. The morphology of the blends was found to be affected by their compositions and processing conditions.  相似文献   

15.
酞侧基聚芳醚砜(PES-C)与聚苯硫醚(PPS)具有部分相容性,虽然PPS的强度和韧性均低于PES-,但PPS含量为2%~10%的PES-C/PPS共混物在保持PES-C原有强度,断裂伸长率的同时,模量略增,冲击强度有很大幅度提高,熔融指数亦蛔。  相似文献   

16.
马宇  王军佐 《应用化学》1996,13(5):25-28
用WAXD、SEM及力学性能测试等研究热致液晶/PEEK/嵌段共聚物三元共混体系形态、结构和性能。结果表明嵌段共聚物的加入,使体系具有一定的相容性和较好的界面粘接,共混物的强度、模量有一定的提高,对共混物的结晶行为具有明显的影响,当热致液晶含量高时,基材与液晶两相间出现明显的分离现象,即“皮-芯”结构.  相似文献   

17.
Nylon‐6/glass‐fiber (GF)/liquid‐crystalline‐polymer (LCP) ternary blends with different viscosity ratios were prepared with three kinds of nylon‐6 with different viscosities as matrices. The rheological behaviors of these blends were characterized with capillary rheometry. The morphology was observed with scanning electron microscopy and polarizing optical microscopy. This study showed that although LCP did not fibrillate in binary nylon‐6/LCP blends, LCP fibrillated to a large aspect ratio in some ternary blends after GF was added. The addition of 5 wt % LCP significantly reduced the melt viscosity of nylon‐6/GF blends to such an extent that some nylon‐6/GF/LCP blends had quite low viscosities, not only lower than those of neat resins and nylon‐6/GF blends but also lower than those of corresponding nylon‐6/LCP blends. The mutual influence of the morphology and rheological properties was examined. The great reduction of the melt viscosity was considered the result of LCP fibrillation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1619–1627, 2004  相似文献   

18.
Poly(lactic acid) (PLA) and polypropylene (PP) blends of various proportions were prepared by melt-compounding. The miscibility, phase morphology, thermal behavior, and mechanical and rheological properties of the blends were investigated. The blends were immiscible systems with two typical morphologies, spherical droplet and co-continuous, and could be obtained at various compositions. Complex viscosity, storage modulus and loss modulus depend on the PP content. Thermal degradation of all blends led to two weight losses, for PLA and PP. The incorporation of PP improved the thermal stability of the blend. The effect of compatibilizer (ethylene-butyl acrylate-glycidyl methacrylate terpolymer, EBA-GMA) on the morphology and mechanical properties of 70/30 w/w PLA/PP blends was investigated. The tensile strength of these blends reached a maximum for 2.5 wt% EBA-GMA, and impact strength increased with increasing EBA-GMA content, suggesting that EBA-GMA is an effective compatibilizer for PLA/PP blends.  相似文献   

19.
A thermoplastic, poly(ethersulfone) (PES) was used to modify a bisphenol‐F based epoxy resin cured with an aromatic diamine. The initial mixtures before curing, prepared by melt mixing, were homogeneous. Scanning electron microscopy (SEM) micrographs of solvent‐etched fracture surfaces of the cured blends indicated that phase separation occurred after curing. The cryogenic mechanical behaviors of the epoxy resins were studied in terms of tensile properties and Charpy impact strength at cryogenic temperature (77 K) and compared to their corresponding behaviors at room temperature (RT). The addition of PES generally improved the tensile strength, elongation at break, and impact strength at both RT and 77 K except the RT tensile strength at 25 phr PES content. It was interesting to observe that and the maximum values of the tensile strength, elongation at break, and impact strength occurred at 20 phr PES content where a co‐continuous phase formed. Young's modulus decreased slightly with the increase of the PES content. Moreover, the tensile strength and Young's modulus at 77 K were higher than those at RT at the same composition, whereas the elongation at break and impact strength showed the opposite results. Finally, the differential scanning calorimetry analysis showed that the glass transition temperature (Tg) was enhanced by the addition of PES. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 612–624, 2008  相似文献   

20.
用扫描电子显微镜图像分析研究了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态结构,计算了表征相结构和尺寸的结构参数,如分散相的平均直径、平均弦长和分散相的质心相关距等.并分别讨论了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态以及其结构参数与共混物组成的关系.测定了聚合物及其共混物体系的力学性能,讨论了共混物组成与力学性能的关系.聚丙烯/聚酰胺1010共混物的拉伸模量与组成的关系较为复杂,但其部分相容体系的拉伸模量与组成呈线性关系.聚丙烯/聚酰胺1010及其共混物体系的屈服强度与共混物组成均呈线性关系.表征相结构的两相平均弦长比(l-1/-l2)与组成以及共混物体系力学性能与组成的关系,二者相似.同时讨论了体系力学性能随相尺寸等的变化规律.  相似文献   

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