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以4,6-二氨基-1,3-苯二酚盐酸盐为原料,分别和对苯二甲酸、1,4-萘二甲酸、2,6-萘二甲酸、2,5-噻吩二甲酸、4,4-′(1,2-二苯基乙烯)二甲酸在多聚磷酸介质中反应,合成单环的聚(1,4-亚苯基)苯并二噁唑(PBO)、稠环的聚(1,4-亚萘基)苯并二噁唑(1,4-PNBO)和聚(2,6-亚萘基)苯并二噁唑(2,6-PNBO)、杂环的聚(2,5-亚噻吩基)苯并二噁唑(PTBO)及含有两个苯环的聚-4,4′-亚(1,2-二苯乙烯基)苯并二噁唑(4,4′-PDPEBO).采用傅立叶红外光谱、热重分析、元素分析、特性黏数分析对系列聚合物进行了表征.研究结果表明PBO、1,4-PNBO、4,4-′PDPEBO、2,6-PNBO和PTBO 5种聚合物的耐热性能依次降低,特性黏数依次为25.40、16.76、20.63、15.38和14.63 dL/g. 相似文献
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聚苯并双噁唑酰亚胺的热分解动力学研究 总被引:1,自引:0,他引:1
采用二步法合成了以2,6-二(对-氨基苯)苯[1,2-d;5,4-d’]二噁唑和1,4-二(3,4-二苯氧基)苯四甲酸二酐(HQDPA)为单体的聚苯并双噁唑酰亚胺.该聚酰亚胺的预聚体聚酰胺酸的黏度为1.70 dL/g,经过热环化后能够生成浅黄色的聚酰亚胺薄膜.通过热重分析法研究了聚苯并双噁唑酰亚胺在N2气氛中的热降解机理.采用Flynn-Wall-Ozawa和Friedman法计算了聚苯并双噁唑酰亚胺热降解表观活化能,分别为356.36kJ/mol和370.54 kJ/mol,平均值为363.45 kJ/mol;反应级数为4.22,指前因子为6.44×1016s-1.采用Coast-Redfern法和Phadnis-Deshpande法研究了聚苯并双噁唑酰亚胺的热降解固相反应机理,认为该聚酰亚胺的热降解机理属于反曲线(A3)机理,是成核和增长模式(Avrami equation 2方程)控制的热降解反应,积分形式为g(X)=[-ln(1-X)]3. 相似文献
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利用70keV能量的氮离子对聚苯并二噁唑(PBO)薄膜进行常温下离子注入表面改性,注入剂量(每平方厘米注入的氮离子数)从1×10~(15)N~+/cm~2到5×10~(16)N~+/cm~2。采用红外(FTIR)、拉曼(Raman)、光电子能谱(XPS)及原子力显微镜(AFM)对其表面结构、组成及形貌进行了表征。研究了氮离子注入剂量对PBO薄膜表面结构与性能的影响。结果表明:注入氮离子后,薄膜表面发生化学键的断裂和交联,近表面区域发生碳化。随氮离子注入剂量的增加,表面粗糙度增加,表面接触角从93°降低到60°,表面润湿性提高了35%,电导率提高到5.7×10~(-9)S/cm,比纯PBO薄膜增加了3个数量级。 相似文献
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噁唑、苯并噁唑及1,3,4-噁二唑硫醚的合成及抗肿瘤活性研究 总被引:1,自引:0,他引:1
设计并以噁唑、苯并噁唑及1,3,4-噁二唑硫醇与卤代烃反应合成了14个硫醚类杂环化合物, 其中13个化合物未见文献报道. 目标化合物的结构均通过1H NMR谱、MS和元素分析进行了表征. 采用MTT [3-(4,5-dimethylthiagol-2-yl)- 2,5-diphenyltetrogolium bromide]法对14个目标化合物进行了体外抗肿瘤活性测定, 结果表明: 在10-5 mol/L 浓度下, 10个化合物对肿瘤细胞具有抑制活性. 相似文献
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金俊弘杨胜林李光江建明 《高分子通报》2013,(10):60-70
聚苯撑苯并二噁唑(PBO)纤维具有超高强度和模量、优异的耐热性和阻燃性,是一种在国防军工、航空航天等领域有重要应用价值的有机高性能纤维。本文综述了国内外PBO纤维的发展历程、纤维的性能,重点介绍了制备高分子量PBO聚合物和纺制高性能PBO纤维的关键技术和先进工艺,提供了改善PBO纤维界面粘结性能、压缩性能和光老化稳定性能的不同技术途径。结果表明:PBO聚合只有多种因素包括单体、工艺、设备等同时优化才能获得高分子量的PBO聚合物,利用双螺杆挤出机同时完成聚合和液晶纺丝成型是工业化连续生产高性能PBO纤维的先进技术路线;通过在PBO大分子链上引入离子基团或双羟基能显著提高PBO纤维与环氧树脂的界面粘结强度,双羟基的存在能使PBO大分子链间建立氢建相互作用从而也提高了PBO纤维的压缩性能,双羟基单体特有的紫外吸收性能更是有效地改善了PBO纤维的光稳定性;在PBO聚合时添加光吸收剂,或在PBO纤维表面涂覆聚酰亚胺都是改善PBO纤维光稳定性的有效方法。 相似文献
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聚苯并噁嗪树脂作为一种新型酚醛树脂,不仅具有优异的耐热性和阻燃性,而且克服了传统酚醛树脂在成形固化过程中释放小分子的缺点,在制备高性能材料方面已引起研究者的广泛关注。本文综述了近年来国内外为制备高性能化聚苯并噁嗪树脂所作的一些研究工作,包括从主链或侧链中引入苯环等刚性官能团、在主链或侧链中引入可聚合官能团、与另一种高分子形成共混或共聚物以及与其他材料复合形成复合材料等,并对该树脂材料的工业开发前景、国内外研究现状以及发展趋势进行了分析。 相似文献
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以含氟的二胺5,5′ (六氟异丙基) 二 (2 氨基苯酚)及均苯四甲酸酐(PMDA)为单体,首先合成了经酰胺化的主链上带有活性羟基的含氟聚酰亚胺,再通过Mitsunobu反应将活性生色分子分散红1(DR1)共价链接到聚酰亚胺的侧链骨架上,合成了含氟聚酰亚胺.采用溶胶 凝胶(Sol Gel)技术,并利用偶联剂γ 氨丙基三乙氧基硅烷(APTES)制备带有发色团的和含有硅氧烷端分子的聚酰胺酸,其中的Si(OR)3基经水解、缩合后,与正硅酸乙酯(TEOS)在催化剂作用下反应,经杂化、凝胶后,得到光学透明且热稳定性高的有机/无机杂化材料.将制得的含氟聚酰亚胺/SiO2杂化材料,采用红外光谱(FT IR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、示差扫描量热法(DSC),对材料的结构、表面形貌、热性能进行了表征. 相似文献
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硫醚双酐聚酰胺酸的合成及其热稳定性 总被引:1,自引:0,他引:1
合成了硫醚二酐和4-硝基-4'-[N,N-二(2-氨乙基)氨基]偶氮苯(二胺单体)及对应的硫醚聚酰胺酸,并对其结构进行表征.由于该发色团分子的一端有可以进一步聚合的氨基,它与硫醚酐所形成的聚酰胺酸在普通有机溶剂中具有良好的可溶性,NLO发色团和聚酰亚胺骨架的分解温度td分别为362℃和491℃,显现出了特殊的热稳定性.目前,这些聚合物在高敏感非线性光学材料方面显示着广泛的应用前景. 相似文献
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Dewen Dong Huiyan Zhuang Guang Li Yushan Ni Mengxian Ding 《Journal of polymer science. Part A, Polymer chemistry》1999,37(2):211-218
Two closely series of poly(ester imide)s had been synthesized by solution polycondensation of p‐phenylenebis(trimellitate) dianhydride with aliphatic diamines. The differential scanning calorimetry (DSC) traces of the most poly(ester imide)s exhibited two endotherms representing the solid state to anisotropic phase transition (Tm1) and the anisotropic to isotropic melt transition (Tm2), respectively. Observation under polarizing microscope and wide‐angle X‐ray diffraction (WAXD) measurements suggested that the anisotropic phase formed above the melting points (Tm1) had a smectic character. The thermogravimetric analyses (TGA) revealed that the thermal stabilities of the poly(ester imide)s were up to 350°C. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 211–218, 1999 相似文献
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SYNTHESIS AND CHARACTERIZATION OF ORGANSOLUBLE POLYIMIDE AND COPOLYIMIDES FROM ALICYCLIC DIANHYDRIDE
Jin-tian Yang Bin Ji Wei Huang Yong-feng Zhou De-yue Yan 《高分子科学》2007,(4):409-417
A kind of highly organsoluble polyimide and copolyimides were successfully synthesized from bicyclo(2.2.2)-oct- 7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA), the commercial diamine 4,4'-methylenedianiline (MDA) and the designed diamine 4,4'-methylenebis-(2-tert-butylaniline) (MBTBA). The polyimide from BCDA and MBTBA is highly soluble in conventional low boiling point solvents (such as chloroform, tetrahydrofuran) at room temperature. But the solubility of the copolyimides in conventional solvents decreased with the molar ratio of MBTBA and MDA decreased. When the molar ratio of MBTBA and MDA was larger than 7/3, the copolyimides can be soluble in low boiling point solvents at room temperature to form a transparent, flexible, tough film by solution casting. When the molar ratio of MBTBA and MDA was between 7/3 and 1/9, they can only be soluble in hot dipolar aprotic solvents (such as DMF, NMP etc.) and form films too. The copolyimide was only soluble in m-cresol when the molar ratio of MBTBA and MDA was lower than 1/9. The number-average molecular weights of the soluble copolyimides were larger than 5.8 × 1064 g/mol by GPC and their polydispersity indices were higher than 1.4. Only one glass transition temperature of these copolyimides was detected around 400℃ by DMA. The copolyimides did not show appreciable decomposition up to 430℃ in N2. 相似文献
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Chin‐Ping Yang Chien‐Wen Yu 《Journal of polymer science. Part A, Polymer chemistry》2001,39(6):788-799
A bis(ether anhydride) monomer, 1,1‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]cyclohexane dianhydride ( IV‐A ), was synthesized from the nitro displacement of 4‐nitrophthalodinitrile by the phenoxide ion of 1,1‐bis(4‐hydroxyphenyl)cyclohexane ( I‐A ), followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and dehydration of the resulting bis(ether acid). A novel series of organosoluble poly(ether imide)s ( VI a–i )(PEIs) bearing cyclohexylidene cardo groups was prepared from the bis(ether anhydride) IV‐A with various aromatic diamines V a–i via a conventional two‐stage process. The PEIs had inherent viscosities in the range of 0.48–1.02 dL/g and afforded flexible and tough films by solution‐casting because of their good solubilities in organic solvents. Most PEIs showed yield points in the range of 89–102 MPa at stress‐strain curves and had tensile strengths of 78–103 MPa, elongations at breaks of 8–62%, and initial moduli of 1.8–2.2 GPa. The glass‐transition temperatures (Tg's) of these PEIs were recorded between 200–234 °C. Decomposition temperatures of 10% weight loss all occurred above 490 °C in both air and nitrogen atmospheres, and their residues were more than 43% at 800 °C in nitrogen atmosphere. The cyclohexane cardo‐based PEIs exhibited relatively higher Tg's, better solubilities in organic solvents, and better tensile properties as compared with the corresponding Ultem® PEI system. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 788–799, 2001 相似文献
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Sheng-Huei Hsiao Kuan-Yu Chu 《Journal of polymer science. Part A, Polymer chemistry》1997,35(11):2281-2287
A naphthalene unit-containing bis(ether anhydride), 2,7-bis(3,4-dicarboxyphenoxy)naphthalene dianhydride, was prepared in three steps starting from the nucleophilic nitrodisplacement reaction of 2,7-dihydroxynaphthalene and 4-nitrophthalonitrile in N,N-dimethylformamide (DMF) solution in the presence of potassium carbonate followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). High-molar-mass aromatic poly(ether imide)s were synthesized using a conventional two-stage polymerization process from the bis(ether anhydride) and ten aromatic diamines. The intermediate poly(ether amic acid)s had inherent viscosities of 0.95–2.67 dL/g. The films of poly(ether imide)s derived from two rigid diamines, that is, p-phenylenediamine and benzidine, crystallized and embrittled during the thermal imidization process. The other poly(ether imide)s belonged to amorphous materials and could be fabricated into transparent, flexible, and tough films. These poly(ether imide) films had yield strengths of 91–115 MPa, tensile strengths of 89–136 MPa, elongation to break of 11–45%, and initial moduli of 1.7–2.2 GPa. The Tgs of poly(ether imide)s were recorded in the range of 222–256°C depending on the nature of the diamine moiety. All polymers were thermally stable up to 500°C, with 10% weight loss being recorded above 540°C in air and nitrogen atmospheres. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2281–2287, 1997 相似文献
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D. Sek A. Wanic E. SchabBalcerzak 《Journal of polymer science. Part A, Polymer chemistry》1997,35(3):539-545
A series of polymers from dinaphthalene dianhydrides and aromatic diamines has been synthesized using one-step high-temperature polycondensation. The influence of the monomers structure on the polymers properties has been investigated. © 1997 John Wiley & Sons, Inc. 相似文献