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采用逐步聚合方法制备了新型特种工程塑料含二氮杂萘酮结构的聚芳醚砜酮[PPESK(1/1)]和聚芳醚砜(PPES).利用热失重(TGA)分析仪,氮气氛围中,多重加热扫描速率下的不定温法对PPESK(1/1)及PPES进行热分解动力学研究.根据Satava法得出,聚合物PPESK(1/1)分解反应机理为随机成核和随后生长,反应级数n=1;而聚合物PPES的热分解反应机理为相界面反应模式,反应级数n=2.同时采用经典动力学方程Friedman、Kissinger-Akahira-Sunose(KAS)及Ozawa方程计算了热分解动力学参数(Ea,lnZ).重点考察升温速率、不同酮/砜比对PPESK(1/1)热稳定性影响,并且根据得到的动力学参数推测其在高温使用条件下的使用寿命及对热分解反应过程中“动力学补偿效应”(KCE)进行分析. 相似文献
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通过三步反应合成新的含氟双酚单体3,4-二氟苯基对苯二酚,由该含氟双酚单体、4-氟苯基对苯二酚、邻苯基对苯二酚分别与4,4′-二氟二苯酮、4,4′-二氯二苯砜经亲核缩聚反应,制备了一系列新型聚芳醚酮和聚芳醚砜。采用 FT-IR、DSC、TGA及XRD手段等对聚合物的结构和性能进行了表征和研究,结果表明:合成的聚芳醚酮和聚芳醚砜具有优异的耐热性能,玻璃化转变温度分别在150~159 ℃和177~196 ℃之间,氮气中5 %热失重温度分别在527 ℃和507 ℃以上。合成的聚芳醚酮和聚芳醚砜具有良好的溶解性,室温下能溶解在N-甲基吡咯烷酮、二甲基乙酰胺、氯仿等有机溶剂中。 相似文献
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聚芳醚酮(PAEK)类树脂属于耐高温、高强度的热塑性工程塑料,作为化工设备重防腐领域中搪玻璃制品的代替品,它已被日本和欧美等国家广为采用。本文从产品开发、应用领域和涂覆工艺等方面论述了PAEK类树脂的发展历程。介绍了国内在PAEK类树脂合成方面所取得的突破:在第一代产品聚醚醚酮(PEEK)的合成中,以新的溶剂环丁砜取代二苯砜,降低了聚合温度,缩短了聚合周期,减少了溶剂消耗,生产效率提高了一倍;在第二代、第三代产品的研发中,立足于国产原料,合成了具有更高耐热等级的PEEKK和PEDEK产品,它们的耐热性比国外产品更好,但成本大幅度下降。 相似文献
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聚芳醚酮(PAEK)类树脂属于耐高温、高强度的热塑性工程塑料,作为化工设备重防腐领域中搪玻璃制品的代替品,它已被日本和欧美等国家广为采用.本文从产品开发、应用领域和涂覆工艺等方面论述了PAEK类树脂的发展历程.介绍了国内在PAEK类树脂合成方面所取得的突破:在第一代产品聚醚醚酮(PEEK)的合成中,以新的溶剂环丁砜取代二苯砜,降低了聚合温度,缩短了聚合周期,减少了溶剂消耗,生产效率提高了一倍;在第二代、第三代产品的研发中,立足于国产原料,合成了具有更高耐热等级的PEEKK和PEDEK产品,它们的耐热性比国外产品更好,但成本大幅度下降. 相似文献
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酞侧基聚芳醚酮拉伸屈服行为的研究 总被引:1,自引:0,他引:1
本文研究了酞侧基聚芳醚酮不同温度与不同形变速率下的拉伸屈服行为,发现屈服应力随温度升高而下降,随形变速率对数值的增大而增加,屈服应力对温度及形变速率的依赖性可用Eyring理论来拟合,屈服能量随温度升高线性下降,从中可以求出屈服时所需热能与机械性能的比。杨氏模,屈服应变亦随温度升高而下降。 相似文献
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通过一种反应条件较为温和的反应新工艺,合成联苯二甲酰氯,即4,4’-二氯甲酰基联苯(BC IBP)。然后,在无水A lC l3及N-甲基吡咯烷酮(NMP)/1,2-二氯乙烷(DCE)复合溶剂的存在下,将2,6-二苯氧基苯甲腈(DPOBN)与BC IBP进行低温缩聚反应,合成了一类新型含氰侧基联苯型聚芳醚醚酮酮。用IR,DSC,TG,WAXD及元素分析等方法对其结构和性能进行了表征。结果表明,所合成的聚合物具有预期结构且为非晶态聚合物;其玻璃化转变温度(Tg)为211℃,在氮气气氛中及在空气气氛中的热分解5%的温度(Td)分别为523℃及498℃,说明其具有突出的耐高温性能;聚合物除了能在浓H2SO4,CF3COOH/CHC l3等强质子性溶剂当中溶解外,对其他的溶剂均不溶解,说明聚合物具有优异的耐化学腐蚀性能。 相似文献
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聚芳醚酮/含甲基侧基聚芳醚砜醚酮酮的合成与表征 总被引:2,自引:0,他引:2
以2,2’-二甲基-4,4'-二苯氧基二苯砜(o-CH3-DPODPS)、二苯醚(DPE)和对苯二甲酰氯(TPC)为单体,在无水A1C13、1,2-二氯乙烷和N,N-二甲基甲酰胺存在下,通过低温溶液缩聚反应。合成了一系列新型含甲基侧基的聚芳醚酮/聚芳醚砜无规共聚物。用FT-IR,WAXD,DSC和TG等方法对聚合物进行了表征。结果表明,随着2,2'-二甲基-4,4'-二苯氧基二苯砜含量的增加,共聚物的玻璃化转变温度逐渐提高,熔融温度则逐渐下降。 相似文献
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Rheological properties of the blends of poly(aryl ether ether ketone) (PEEK) with liquid crystalline poly(aryl ether ketone) containing substituted 3‐trifluoromethylbenzene side group (F‐PAEK), prepared by solution precipitation, have been investigated by rheometer. Dynamic rheological behaviors of the blends under the oscillatory shear mode are strongly dependent on blend composition. For PEEK‐rich blends, the systems show flow curves similar to those of the pure PEEK, i.e., dynamic storage modulus G′ is larger than dynamic loss modulus G″, showing the feature of elastic fluid. For F‐PAEK‐rich systems, the rheological behavior of the blends has a resemblance to pure F‐PAEK, i.e., G″ is greater than G′, showing the characteristic of viscous fluid. When the PEEK content is in the range of 50–70%, the blends exhibit an unusual rheological behavior, which is the result of phase inversion between the two components. Moreover, as a whole, the complex viscosity values of the blends are between those of two pure polymers and decrease with increasing F‐PAEK content. However, at 50% weight fraction of PEEK, the viscosity‐composition curves exhibit a local maximum, which may be mainly attributed to the phase separation of two components at such a composition. The changes of G′ and G″ with composition show a trend similar to that of complex viscosity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4040–4044, 2006 相似文献
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In this communication, we report for the first time the synthesis of a new electroactive poly(aryl ether ketone) derived from the phenyl-capped aniline tetramer. The general properties are studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The polymer has high serving temperature and good thermal stability. And its chemical oxidation process was studied by UV-Vis spectra. It was found the polymer was oxidized to its EB form and then to the pernigraniline oxidation state, which is same as the PANI. 相似文献
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2,6‐Diphenoxybenzonitrile (DPOBN) was synthesized by reaction of phenol with 2,6‐difluorobenzonitrile in N‐methyl‐2‐pyrrolidone in the presence of KOH and K2CO3. Poly(aryl ether ketone ketone)/poly(aryl ether ether ketone ketone) copolymers with pendant cyano groups were prepared by the Friedel–Crafts electrophilic substitution reaction of terephthaloyl chloride with varying mole proportions of diphenyl ether and DPOBN using 1,2‐dichloroethane as solvent and N‐methyl‐2‐pyrrolidone as Lewis base in the presence of anhydrous AlCl3. The resulting polymers were characterized by various analytical techniques, such as FT‐IR, differential scanning calorimeter, thermal gravimetric analysis, and wide‐angle X‐ray diffraction. The crystallinity and melting temperature of the polymers were found to decrease with increase in concentration of the DPOBN units in the polymer. Thermogravimetric studies showed that all the polymers were stable up to 514°C in N2 atmosphere. The glass transition temperature was found to increase with increase in concentration of the DPOBN units in the polymer when the molar ratios of DPOBN to DPE ranged from 10/90 to 30/70. The copolymers containing 30–40 mol % of the DPOBN units exhibit excellent thermostability at (350 ± 10)°C and have good resistance to acidity, alkali, and organic solvents. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3601–3606, 2007 相似文献
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A novel bisphenol monomer, (3-methoxy)phenylhydroquinone, was synthesized via a three-step synthetic procedure. The cyclization of the bisphenol monomer and 4,4-difluorobenzophenone was carried out under pseudo high dilution condition. Two types of fully aromatic poly(aryl ether ketone)s were prepared by copolymerization of macrocycle of aryl ether ketone (MACEK) containing hydroxyphenyl, 4,4′-(hexafluoroisopropylidene)diphenol (HFBPA), and 4,4-difluorobenzophenone. The copolymers have high molecular mass, good solubility and high glass transition temperatures. The copolymers are crosslinkable in the presence of basic initiator and the glass transition temperatures of the copolymers increased greatly after the curing. These cured copolymers exhibit excellent thermal stability, and the 5% weight loss temperatures are around 500 °C in nitrogen. 相似文献
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K. H. Hsieh Y. C. Chern K. S. Hoe Y. Z. Wang B. W. Chan L. W. Chen 《Journal of Polymer Research》1996,3(2):83-88
A series of modified poly(ether ether ketone) (PEEK) polymers were synthesized by introduction of addition ether groups from dihydroxydiphenyl ether (DHDE) into the PEEK structure. The inherent viscosity of the DHDE-modified PEEK increased with reaction time at 320 °C. DSC thermograms showed the melting points of the obtained PEEK decreased with the increase of the DHDE content in the backbone. The degradation temperature (Td) was slightly decreased by the introduction of DHDE. The crystallinity as measured via the X-ray diffraction (XRD) increases with the introduction of DHDE into the modified PEEK. The crystalline structure was identified as an orthorhombic structure with lattice constants a = 7.72 Å, b = 5.86 Å, and c = 10.24 Å. Due to the glass transition temperature (Tg) and the melting temperature (Tm) decreasing with the increase of the DHDE content in the reaction system. the processability of the resultant PEEK could be improved through this DHDE modification. 相似文献