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1.
本文通过研究含氯侧基液晶聚芳醚酮/含甲基苯侧基聚芳醚酮共混体系(结晶/非晶)环带球晶的形态演变和发展过程; 利用选择性溶剂刻蚀方法确定共混体系环带球晶的相组成和相结构, 探讨了环带球晶的形成机理.  相似文献   

2.
Rhythmic growth of ring‐banded spherulites in blends of liquid crystalline methoxy‐poly(aryl ether ketone) (M‐PAEK) and poly(aryl ether ether ketone) (PEEK) has been investigated by means of differential scanning calorimetry (DSC), polarized light microscopy (PLM), and scanning electron microscopy (SEM) techniques. The measurements reveal that the formation of the rhythmically grown ring‐banded spherulites in the M‐PAEK/PEEK blends is strongly dependent on the blend composition. In the M‐PAEK‐rich blends, upon cooling, an unusual ring‐banded spherulite is formed, which is ascribed to structural discontinuity caused by a rhythmic radial growth. For the 50:50 M‐PAEK/PEEK blend, ring‐banded spherulites and individual PEEK spherulites coexist in the system. In the blends with PEEK as the predominant component, M‐PAEK is rejected into the boundary of PEEK spherulites. The cooling rate and crystallization temperature have great effect on the phase behavior, especially the ring‐banded spherulite formation in the blends. In addition, the effects of M‐PAEK phase transition rate and phase separation rate on banded spherulite formation is discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 3011–3024, 2007  相似文献   

3.
Binary melt‐blended mixtures of two aryl ether ketone polymers (i.e., a new poly(aryl ether ketone) (code name PK99) and poly(ether ether ketone) (PEEK), have been studied. Polymer miscibility in glassy amorphous (or melt) domains has been demonstrated for the binary blend comprising of two aryl‐ether‐ketone‐type semicrystalline polymers. Composition‐dependent, single Tg was observed within full composition range in the PK99/PEEK blends, and the narrow Tg breadth also suggests that the scale of mixing was fine and uniform. To better resolve any possible overlapping Tg's, physical aging was imposed on a comparison set of blend samples for the purpose of improving detectability of overlapped multiple transitions if existing. The result still showed one single Tg. The relative sharp Tg and lack of cloud point transition suggest that the scale of molecular intermixing is good. Phase homogeneity was further confirmed using optical and scanning electron microscopy. The X‐ray diffractograms suggest that isomorphism does not exist in the PK99/PEEK blends and that the crystal forms of the respective polymers remain distinct and unchanged by the miscibility in the amorphous region. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1485–1494, 1999  相似文献   

4.
The isothermal melt and cold crystallization kinetics of poly(aryl ether ketone ether ketone ketone) are investigated by differential scanning calorimetry over two temperature regions. The Avrami equation describes the primary stage of isothermal crystallization kinetics with the exponent n ≈ 2 for both melt and cold crystallization. With the Hoffman–Weeks method, the equilibrium melting point is estimated to be 406 °C. From the spherulitic growth equation proposed by Hoffman and Lauritzen, the nucleation parameter (Kg) of the isothermal melt and cold crystallization is estimated. In addition, the Kg value of the isothermal melt crystallization is compared to those of the other poly(aryl ether ketone)s. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1992–1997, 2000  相似文献   

5.
Summary: The ring‐banded spherulites in liquid crystalline poly(aryl ether ketone) (LC‐PAEK) and poly(aryl ether ether ketone) (PEEK) blends with a higher content (>50%) of LC‐PAEK are investigated by polarizing light microscopy (PLM) and atomic force microscopy (AFM) techniques. The results indicate that the light core and rings of the ring‐banded spherulites under PLM are mainly composed of an LC‐PAEK phase, while the dark rings consist of coexisting phases of PEEK and a small amount of LC‐PAEK. The formation of the ring‐banded spherulites is attributable to structural discontinuity caused by a rhythmic radial growth.

PLM image of ring‐banded spherulites in a 70:30 LC‐PAEK/PEEK blend caused by rhythmic growth.  相似文献   


6.
几种甲基取代的聚醚酮酮的合成与表征   总被引:1,自引:0,他引:1  
盛寿日  宋才生 《应用化学》1999,16(2):109-107
聚芳醚酮是一类热、电、机械性能优异的热塑性工程塑料,其合成方法有亲电取代法和亲核取代法.近年来,通过改变主链上醚酮键的比例和次序以及在主链上引入sp3杂化原子团,如砜基、烷基,对其进行结构上的改性研究已有很多报道[14].另一种结构上的改性研究是在...  相似文献   

7.
Two series of novel amorphous poly(aryl ether phthalazine)s have been prepared via an intramolecular ring closure reaction of poly(aryl ether ketone)s (PAEKs) with hydrazine monohydrate. Fluorinated PAEKs, which display solubility in solvents incorporating a ketone functionality such as acetone or ethyl acetate, were converted to poly(aryl ether phthalazine)s to observe if these polymers would display similar solubility characteristics. The poly(aryl ether phthalazine)s have glass transition temperatures in the range of 278–320°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. The fluorinated poly(aryl ether phthalazine)s were not soluble in ketonic solvents. A series of poly(aryl ether phthalazine)s incorporating pendant 2-naphthalenyl moieties has been prepared in an attempt to produce amorphous, thermally stable polymers with high glass transition temperatures. The polymers have glass transition temperatures in the range of 287–334°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. Poly(aryl ether phthalazine)s undergo an exothermic reaction above the glass transition temperature. The major product of this reaction is a rearrangement of the phthalazine moieties to quiazoline moieties, however some crosslinking of the polymers occurs. Cured samples of the poly(aryl ether phthalazine)s show a small increase in the polymer Tg and are insoluble in all solvents tested. © 1996 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 34:1897–1905, 1996  相似文献   

8.
Two novel fluorinated monomers were prepared and polymerized with biphenols to produce amorphous, thermally stable poly(aryl ether ketone)s. The properties of the fluorinated polymers are compared to those of unfluorinated, amorphous poly(aryl ether ketone)s. The presence of fluorine in the polymers was found to cause a decrease in glass transition temperature and Young's moduli, however, no increase in thermal stability was observed. The fluorinated polymers are soluble in common organic solvents such as chloroform and methylene chloride at room temperature, and also show solubility in solvents containing a ketonic moiety, such as acetone. Evidence of polymer branching through fluorines considered to be unreactive under the polymerization conditions was found. Efforts were made to evaluate the reactivity of fluorine atoms under the polymerization conditions using both molecular modeling and 19F-NMR to ascertain if such branching could be avoided. © 1995 John Wiley & Sons, Inc.  相似文献   

9.
通过氧化偶联聚合方法成功地合成出电活性聚芳醚酮. 该反应条件温和, 操作简单, 室温下即可进行. 用红外光谱、核磁共振谱、高效凝胶渗透色谱、循环伏安、热失重、X射线衍射等技术对所合成的聚合物进行了表征, 并探讨了聚合物的性能.  相似文献   

10.
通过联苯二酚(介晶基元)、取代对苯二酚(破坏结晶基元)与4,4'-二氟二苯酮的亲核取代反应合成了一系列具有液晶性的新型聚芳醚酮,采用DSC、PLM和WAXD等方法对聚合物的研究表明:联苯含量为70%时聚合物表现为向列相,联苯含量为50%时聚合物出现近晶相,在外力场作用下,向列相液晶容易形成明暗交替的条带织构.  相似文献   

11.
The relationships among glass transition, crystallization, melting, and crystal morphology of poly(aryl ether ketone) (PAEK)/poly(other imide) (PEI) blends was studied by thermal, optical and small-angle x-ray scattering (SAXS) methods. Two types of PAEK were chosen for this work: poly(aryl ether ether ketone), PEEK, and poly(aryl ether ketone ketone), PEKK, which have distinctly different crystallization rates. Both PAEKs show complete miscibility with PEI in the amorphous phase. As PAEK crystallizes, the noncrystallizable PEI component is rejected from the crystalline region, resulting in a broad amorphous population, which was indicated by the broadening and the increase of Tg over that of the purely amorphous mixture. The presence of the PEI component significantly decreases the bulk crystallization and crystal growth rate of PAEK, but the equilibrium melting temperature and crystal surface free energies are not affected. The morphology of the PEI segregation was investigated by SAXS measurements. The results indicated that the inter(lamellar-bundle) PEI trapping morphology was dominant in the PEEK/PEI blends under rapid crystallization conditions, whereas the interspherulitic morphology was dominant in the slow crystallizing PEKK/PEI blends. These morphologies were qualitatively explained by the expression δ=D/G, where G was the crystal growth rate and D was the mutual diffusion coefficient. © 1993 John Wiley & Sons, Inc.  相似文献   

12.
含联苯结构聚醚醚酮酮共聚物和共混物的制备及性能研究   总被引:8,自引:0,他引:8  
聚醚醚酮(PEEK)是八十年代初投入市场的全芳香结构热塑性耐高温特种工程塑料,它的7’。一143“C,Tm一334C“‘,最大结晶度为48%,典型制品结晶度为20%~30%[”.PEEK可用通常的设备成型,其制件、纤维、涂料及复合材料在电子电器、机械设备、交通运输、宇航、原子能工程、军事等领域有广泛的用途[’j.聚醚醚酮酮(PEEKK)是继PEEK之后,由德国Hoechst公司开发出来的又一种全芳香结构热塑性耐高温特种工程塑料[‘j.为了研究该类聚合物的结构和性能的关系,我们在实验室中合成了PEEKK和含联苯结构聚醚醚酮酮(PE-*…  相似文献   

13.
Dynamic rheological measurements were carried out on blends of poly(ether ether ketone) (PEEK)/poly(aryl ether sulfone) (PES) in the melt state in the oscillatory shear mode. The data were analyzed for the fundamental rheological behavior to yield insight into the microstructure of PEEK/PES blends. A variation of complex viscosity with composition exhibited positive–negative deviations from the log‐additivity rule and was typical for a continuous‐discrete type of morphology with weak interaction among droplets. The point of transition showed that phase inversion takes place at composition with a 0.6 weight fraction of PEEK, which agreed with the actual morphology of these blends observed by scanning electron microscopy. Activation energy for flow, for blend compositions followed additive behavior, which indicated that PEEK/PES blends may have had some compatibility in the melt. Variation of the elastic modulus (G′) with composition showed a trend similar to that observed for complex viscosity. A three‐zone model used for understanding the dynamic moduli behavior of polymers demonstrated that PEEK follows plateau‐zone behavior, whereas PES exhibits only terminal‐zone behavior in the frequency range studied. The blends of these two polymers showed an intermediate behavior, and the crossover frequency shifted to the low‐frequency region as the PEEK content in PES increased. This revealed the shift of terminal‐zone behavior to low frequency with an increased PEEK percentage in the blend. Variation of relaxation time with composition suggested that slow relaxation of PEEK retards the relaxation process of PES as the PEEK concentration in the blend is increased because of the partial miscibility of the blend, which affects the constraint release process of pure components in the blend. A temperature‐independent correlation observed in the log–log plots of G′ versus loss modulus (G″) for different blend systems fulfilled the necessary condition for their rheological simplicity. Further, the composition‐dependent correlations of PEEK/PES blends observed in a log–log plot of G′ versus G″ showed that the blends are either partially miscible or immiscible and form a discrete‐continuous phase morphology. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1548–1563, 2004  相似文献   

14.
通过傅克酰基化反应合成4,4'-二(4-氟苯甲酰基)二苯醚、4,4'-二(五氟苯甲酰基)二苯醚、4,4'-二(4-氟苯甲酰基)二苯硫醚以及4,4'-二(五氟苯甲酰基)二苯醚4种长链双卤单体,并进一步制备了含二氮杂萘酮聚芳醚酮聚合物.通过多氟取代双卤单体在含二氮杂萘酮聚芳醚酮聚合物主链中引入氟原子.多氟取代双卤单体具有多...  相似文献   

15.
聚醚醚酮/聚醚醚酮酮共混体系的熔融和等温结晶行为   总被引:3,自引:0,他引:3  
采用熔融共混方法制备了聚醚醚酮和聚醚醚酮酮的共混物,用DSC对共混物的熔融行为和等温结晶行为进行了研究.结果表明,共混物熔点随聚醚醚酮含量增加而降低,但与聚醚醚酮酮有相同的平衡熔点,二者共混没有改变其结晶的成核与生长机制.  相似文献   

16.
The transport of fluids in the semicrystalline polymer, poly(aryl ether ether ketone) (PEEK), was investigated. Both solubility and rate of penetration of toluene into PEEK are markedly increased by the application of an external stress. The induction period (i.e., the time for the sorption to begin) is a function of applied stress as well as temperature and crystallinity. At 22°C in 29% crystalline PEEK the induction period was reduced from more than 2000 h to approximately 10 h whereas the solubility of toluene was increased from 9 to 44 wt % upon the application of an external tensile stress of 30 MPa. A critical stress (i.e., a stress value below which the stress-enhanced effects are not observed) was determined. The critical stress is a strong function of crystallinity and temperature. © 1996 John Wiley & Sons, Inc.  相似文献   

17.
高Tg含萘聚芳醚酮的合成与性能   总被引:3,自引:0,他引:3  
利用Friedel-Craft和去醚化反应成功地制备了具有对称取代结构的含萘双酚单体1,5-二(3-甲基)苯羰基-2,6-二羟基萘, 并且通过高温亲核取代反应制得了两种高分子量的芳香族聚合物, 对这两种新型聚合物的热性能、溶解性能、机械性能及介电常数等进行了表征.  相似文献   

18.
含间苯基聚醚醚酮酮的合成与性能研究   总被引:5,自引:0,他引:5  
含间苯基聚醚醚酮酮的合成与性能研究林权,王一凡,张万金,吴忠文,尹玖梅(吉林大学化学系,长春,130023)(中国科学院长春应用化学研究所)关键词聚醚醚酮酮,间苯基,熔点,玻璃化转变温度聚芳醚酮类高聚物具有优异的热、电、机械性能.全对苯基位聚醚醚酮酮...  相似文献   

19.
刘勇军  钟鸣  宋琤  盛寿日  侯豪情  宋才生 《应用化学》2018,35(11):1289-1294
以苯酚、对二溴苯及苯基磷酰二氯为原料合成出二(4-苯氧基苯基)苯基氧磷(BPOPPO)。 三氯化铝(AlCl3)为催化剂,通过缩聚反应,BPOPPO与对苯二甲酰氯(TPC)反应制备出一种含有三苯基氧磷结构的聚醚醚酮酮(P-PEEKK)树脂。 采用傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、热重分析仪(TGA)和广角X射线衍射(WAXD)等技术手段对P-PEEKK树脂的结构和性能进行表征。 结果表明,P-PEEKK树脂属于非晶聚合物,玻璃化转变温度(Tg)较高,为190.5 ℃;热分解温度(T5%)为515 ℃,耐热性能较好;极限氧指数(LOI)为42,阻燃性能好,为难燃材料;易溶解于氯仿、1,2-二氯乙烷、N,N-二甲基乙酰胺等有机溶剂中,溶解性能较好,便于涂膜加工;拉伸强度为62 MPa,力学性能较好。  相似文献   

20.
聚芳醚酮与液晶聚酯多嵌段共聚物的合成表征   总被引:1,自引:0,他引:1  
近年来,以热塑性聚合物为基体,热致液晶聚合物(TLCP)作为增强剂的高分子原位复合材料由于其具有优异的机械性能和优良的成型加工性能,已引起各国工作者的普遍关注和极大兴趣.然而由于自聚集和相分离作用的影响,大部分液晶聚合物与通常的热塑性聚合物基体基本不相容或弱相容,这对于提高原位复合材料的力学性能不利.  相似文献   

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