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1.
新型含氟耐高温聚吡咙——合成与性能研究   总被引:3,自引:0,他引:3  
通过改进的Chichibabin反应合成了主链含有吡啶单元的新型含氟四胺单体 ,2 ,6 双 (3′ ,4′ 二氨基苯基 ) 4 (3″ ,5″ 双三氟甲苯基 )吡啶 (6FPA) .利用 6FPA与芳香族二酐单体 3,3′ ,4 ,4′ 二苯醚四羧酸二酐 (ODPA)通过两步热环化工艺制备了新型聚吡咙 (Polypyrrolone ,PPy)化合物 .对其所进行的各种性能测试结果表明 ,这种主链含有刚性吡啶结构、侧链带有含氟取代基的芳杂环高分子材料不仅保持了其固有的耐热性能 ,而且具有优良的成膜性能与耐水解性能 .例如其起始热分解温度为 5 5 8℃ ,失重 10 %温度为 5 91℃ ,72 0℃时的残余重量百分数为 6 8% ,玻璃化转变温度为 318℃ .PPy薄膜在 10 %NaOH水溶液中水解 7天仍具有良好的耐热性能与柔韧性 .  相似文献   

2.
采用以甲苯为聚合介质的ATRP聚合体系,以双甲基丙烯酸二醇酯为单体,合成了具有二十和二十八元环的线形环化聚合物,聚合物具有窄分子量分布.聚合动力学显示随着链长的增加,环化反应速率变慢.根据聚合物的1H-NMR谱图、由1H-NMR端基分析得到聚合度DPNMR、以及GPC图谱结果,证实获得了线形环化聚合物.TGA测试结果表明2种聚合物的起始分解温度均大于372℃,具有比PMMA更好的热稳定性.  相似文献   

3.
刘成杰  洪珊 《化学研究与应用》2007,19(10):1080-1083,1088
本文合成了含长烷基侧链的二胺单体3,5-二氨基苯甲酸(4-烷氧基)苯酯,然后使它与2,2-双[4.(3,4-二羧酸基苯氧基)苯基]丙烷二酐在N甲基-2-吡咯烷酮溶液中聚合,再通过化学酰亚胺化得到一系列含有长烷基侧链的聚酰亚胺。聚酰亚胺的结构经红外光谱和核磁共振氢谱确认,并对它的溶解性能、特征粘数、光学性能和热性能等进行了表征。结果表明,所合成的聚酰亚胺具有好的溶解性能、较高的分子量、优异的透光率和较好的热稳定性。  相似文献   

4.
吡啶桥联的聚酰亚胺的合成与性能研究   总被引:2,自引:0,他引:2  
以3,4-二甲基苯乙酮与3,5-双(三氟甲基)苯甲醛为原料,通过Chichibabin反应制备了吡啶桥联的四甲基化合物,该化合物再经氧化、脱水反应制备了主链含有吡啶环、侧链带有双三氟甲基取代苯侧基的新型含氟芳香族二酐单体,2,6双(3′,4′-二羧基苯基)-4-(3″-,5″-双三氟甲基苯基)吡啶二酐(6FDAPA).FT IR、NMR、质谱以及元素分析等测试结果表明,6FDAPA的结构与预期的相符.利用6FDAPA与另外一种不含氟的二酐单体2,6双(3′,4′二羧基苯基)4苯基吡啶二酐(DAPA)分别与含氟二胺单体,1,4双(2三氟甲基4氨基苯氧基)苯(6FAPB)通过两步热亚胺化法制备了两种聚酰亚胺(PI)薄膜.测试结果表明,6FDAPA6FAPB(PI2)与DAPA6FAPB(PI1)相比具有相近的耐热性能,玻璃化转变温度为280℃,起始热分解温度为580℃、700℃时的重量保持率64.5%.同时PI2具有更为优良的透光性,紫外可见光谱(UV Vis)测试表明,PI2与PI1薄膜在450nm处的透光率分别为85.7%与69.4%.  相似文献   

5.
合成了含液晶基元侧基的二氨基化合物-3,5-二氨基苯甲酸-4′-联苯酯,并以3,3′-4,4′-二苯醚四羧酸二酐(ODPA)、二氨基二本醚(ODA)为共聚单体,制备了具仍液晶侧链原位复合自增强功能的新型聚酰亚胺(PI)薄膜材料,这种含液晶基元侧链的PI能溶 在极性非质子有机溶剂中,显示出良好的可加工性能,由于液晶基元侧链的原位复合自增强作用,该类膜材料显示出良好的力学性能和热稳定性在热台偏光显微镜下观察,该类聚合物在较高的温度区域内显示液晶行为,并呈现向相织构。  相似文献   

6.
合成了含液晶基元侧基的二氨基化合物——— 3,5 二氨基苯甲酸 4′ 联苯酯 ,并以 3,3′ 4,4′ 二苯醚四羧酸二酐 (ODPA)、二氨基二苯醚 (ODA)为共聚单体 ,制备了具有液晶侧链原位复合自增强功能的新型聚酰亚胺 (PI)薄膜材料 .这种含液晶基元侧链的PI能溶解在极性非质子有机溶剂中 ,显示出良好的可加工性能 .由于液晶基元侧链的原位复合自增强作用 ,该类膜材料显示出良好的力学性能和热稳定性能在热台偏光显微镜下观察 ,该类聚合物在较高的温度区域内显示液晶行为 ,并呈现向列相织构  相似文献   

7.
在碱催化条件下,利用N,N-二乙基氯乙胺盐酸盐与瓜尔胶和羟丙基瓜尔胶一步法合成得到N,N-二乙基胺乙基瓜尔胶和N,N-二乙基胺乙基羟丙基瓜尔胶。结果显示合成过程中温度、反应时间、羟丙基取代度及溶剂等因素对产品分子量和N,N-二乙基胺乙基取代度有影响。通过红外光谱和核磁法对N,N-二乙基胺乙基瓜尔胶和羟丙基N,N-二乙基胺乙基瓜尔胶的分子结构进行了分析,并通过碳谱对N,N-二乙基胺乙基在瓜尔胶分子链中糖环上的取代分布进行了分析。  相似文献   

8.
用2,5-双-(间甲酰基苯基)-1,3,4-噁二唑和相应的二胺,经[2 2]缩合环化反应,合成了三个含二苯联噁二唑的新型大环多胺4、5和7以及5的钡络合物。  相似文献   

9.
使用3,3′,4,4′-二苯醚四酸二酐(ODPA)、3,3′,4,4′-联苯四酸二酐(BPDA)、1,3-双(4-氨基苯氧基)苯(1,3,4-APB)、3,4′-二氨基二苯醚(3,4′-ODA)和反应性封端剂4-苯乙炔苯酐(4-PEPA)合成了设计分子量为5000的系列苯乙炔基封端的聚酰亚胺低聚物,并使用XRD、DSC、TGA、FT-IR、DMA和流变仪等对低聚物的化学结构、热性能和熔体性能,固化后树脂的热性能和力学性能进行了测试.研究结果表明基于ODPA的低聚物具有低的熔体粘度和良好的熔体粘度稳定性,固化后的树脂具有很高的热失重温度,较高的玻璃化转变温度以及良好的力学性能尤其是高的断裂伸长率(>10%);基于BPDA的低聚物具有一定的结晶性,其结晶熔融温度与苯乙炔基固化交联温度相近,影响了材料的成型工艺性能.  相似文献   

10.
利用脂肪族二元酸酯与乙醇胺反应容易获得的对称二酰胺二醇,经缩聚合成聚酯酰胺预聚体,并针对端羧基和端羟基同时扩链来提高分子量,获得可生物降解的聚酯酰胺.首先将N,N′-二(2-羟乙基)草酰胺(HEOA)或N,N′-二(2-羟乙基)己二酰胺(HEHA)与己二酸和丁二醇缩聚,制备同时带有端羧基及端羟基的脂肪族聚酯酰胺预聚体,通过1,4-双(2-噁唑啉)苯及己二酰双己内酰胺混合扩链剂扩链,获得高分子量脂肪族聚酯酰胺,并通过红外、1H-NMR、DSC及TGA对其结构和热性能进行了表征.结果表明,预聚体在制备过程发生了一定的酯-酰胺交换反应;扩链后聚合物的熔点、熔融焓和热稳定性有所下降;但热稳定性仍接近或略高于聚己二酸丁二酯.  相似文献   

11.
The copolyimides derived from 3,4′‐oxidianiline (ODA), 4,4′‐oxydiphthalic anhydride (ODPA) and 3,3′,4,4′‐biphenyl dianhydride (BPDA) were synthesized in N,N‐dimethyl acetamide (DMAc) by a two‐step method. To control molecular weight, phthalic anhydride (PA) was used as an end‐capping reagent. The effect of far‐infrared radiation (FIR) on imidization of copolyimides was investigated by Fourier transform infrared spectroscopy (FT‐IR) and Thermogravimetric analysis (TGA), and was compared to conventional electrothermal imidization. The effect of imidization time and film thickness on weight loss of imidization process was also studied. The results show that the FIR can accelerate the imidization process of copolyimides compared with the conventional electrothermal treatment especially during the primary curing period. Weight loss of thin film is faster than that of thick film. In addition, molecular weight will influence the imidization process. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2154–2160, 2005  相似文献   

12.
As a nondestructive method of evaluation, we have used integrated optics to investigate thin films (<8 μm) of polyamic acid and polyimide as a function of molecular weight, initial imidization temperature, method of imidization, and annealing treatment. Polyamic acid films were found to exhibit a large optical anisotropy, indicating preferential alignment of the long axis of the molecule in the plane of the film. Imidization increased the birefringence of the film by a factor of 2.5 and reduced the film thickness. The only parameter that was found to effect the anisotropy of the films was the method of imidization. Chemical imidization was found to increase the birefringence by a factor of 3, indicative of a higher degree of molecular orientation parallel to the film surface. This effect was not observed in thicker (>25-μm) films using x-ray diffraction where the orientation function was found to be independent of the method of imidization.  相似文献   

13.
The kinetics and mechanisms of the solution imidization of polyamic acid resulting from a diamine, bis(4‐aminophenoxy‐3,5‐dimethylphenyl)naphthylmethane, and a dianhydride, 3,3′4,4′‐diphenylsulfonetetracarboxylic dianhydride, were studied at three various temperatures (145, 165, and 180 °C). The results were confirmed by means of 1H NMR and gel permeation chromatography (GPC). Kinetic parameters were obtained by an isothermal study, and the results were quite close to second‐order kinetics for the homogeneous solution imidization. In addition, Carother's equation, Mark–Houwink theory, and GPC were used to explain the molecular weight of the imidization processes. The apparent activation energy (Ea) was 104 KJ/mol, and the pre‐exponential factor (k0) was 3.48 × 1014. The proposed kinetic mechanism is in good agreement with the kinetic models. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4139–4151, 2001  相似文献   

14.
以4,4′-二氨基二苯硫醚(SDA)和均苯四酸酐(PMDA)为原料,通过溶液缩聚法-热酰亚胺/化学酰亚胺化的方法制备了一种含硫醚结构均苯型聚酰亚胺.利用高级旋转流变仪建立了在线跟踪反应进程的方法,采用热失重分析仪研究反应条件对热酰亚胺化及化学酰亚胺化法的影响,这些方法的建立为进一步制备高性能的聚酰亚胺提供有效的实验手段.采用小角激光光散射法、红外光谱、元素分析、接触角仪、DSC等方法对聚合物的结构与性能进行表征.结果显示,硫醚结构的引入,可有效改善聚合物薄膜的表面性能,其与铜箔之间的粘附功明显大于传统聚酰亚胺,在无胶挠性线路板应用方面显示出较好的应用前景.所获聚合物的Mw为(6.7±1.6)×104,分解温度均高于560℃;DSC的结果显示所制备的两种酰亚胺化聚合物均具有较高的玻璃化转变温度,相比之下,化学酰亚胺化更有利于获得高酰亚胺化程度的聚合物,产物的玻璃化转变温度也更高.  相似文献   

15.
设计并合成了一种含氟苯乙炔苯胺封端剂4-苯乙炔基-3-三氟甲基苯胺(3FPA),使用3FPA与4,4′-(六氟异丙基)双邻苯二甲酸二酐(6FDA)和对苯二胺(p-PDA)制备了计算分子量为5000的聚酰亚胺树脂3FPA-PI-50,并对树脂溶液、树脂模塑粉和树脂模压件的制备与性能进行了研究,实验结果表明3FPA-PI-50树脂溶液具有良好的储存稳定性,成型后树脂具有优异的热性能和热氧化稳定性,后固化后树脂玻璃化转变温度为404℃,5%热失重温度大于530℃.此外树脂具有低的介电常数和吸水率.  相似文献   

16.
In this paper, the monomers 4,4′‐oxydiphthalic anhydride (ODPA), 3,3′,4,4′‐biphenyl dianhydride (BPDA), 3,4′‐oxidianiline (3,4′‐ODA), and 4,4′‐oxidianiline (4,4′‐ODA) were selected to synthesize polyimides (PI) or copolyimides (co‐PI) in N,N‐dimethyl acetamide (DMAc) by two‐step method. To control the PI molecular weight (MW), phthalic anhydride (PA) was used as the end‐capping reagent. The effect of far‐infrared radiation (FIR) on PI imidization was investigated by Fourier transform infrared spectroscopy (FTIR). Some factors affecting imidization process in FIR were discussed, including PI imidization time and temperature, molecular structure, designed number average molecular weight, crystalline, imidization procedure, film thickness, polyamide acid (PAA) solid content, and so forth. The PI imidization process in FIR will be affected by all these factors. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3621–3627, 2005  相似文献   

17.
一种主链含光敏基团聚酰亚胺的合成与表征   总被引:1,自引:0,他引:1  
郭妙才  王晓工 《高分子学报》2008,(11):1113-1117
通过4,4′-二羟乙基查尔酮与1,2,4-苯三酸酐酰氯反应,得到了一种新型的主链含查尔酮的二酐单体,通过二酐和2,2-双(3(-氨基-4(-羟基苯基)六氟丙烷缩聚并高温亚胺化,得到了一种新型的主链含查尔酮,侧链含羟基的光敏聚酰亚胺,并通过1H-NMR、FTIR、GPC及热分析表征了得到的聚酰亚胺的结构和热性能.这种聚酰亚胺在极性溶剂中具有较好的溶解性,并具有较高的热稳定性,在紫外光照射下,能进行[2+2]的环加成反应.  相似文献   

18.
Two thermoplastic polyimides based on a common diamine (3,4′-ODA) were synthesized using different dianhydrides, namely ODPA and BPDA by a two step method. Molecular weight was controlled by using PA as an end capping agent. Effects of imidization degree on the mechanical properties and viscoelastic behavior of thermoplastic polyimide films were investigated. Film samples with varying degrees of imidization were characterized using FTIR, DMTA and tensile properties testing. It was found that two polyimides have different rates of imidization because of difference in monomer reactivity and molecular structure. It was observed that with an increase in imidization degree there was a decrease in thermoplastic response and a change in viscoelastic behavior from liquid-like to solid-like. With increase in imidization degree the tensile modulus and tensile strength of the films were increased, whereas elongation at break and tensile breaking energy were found to decrease after a certain imidization temperature.  相似文献   

19.
Crosslinking of linear poly[2,2′-(1,4-phenylene)-6,6′-bis(3-phenylquinoxaline)] (PPQ) by isothermal heat exposure in the temperature range between 425 and 490°C was investigated by means of torsional braid analysis. The change in glass transition temperature due to isothermal exposure was used as a kinetic parameter. In order to determine the effect of molecular weight and type of polymer chain ends, three PPQ samples were prepared that differed only in molecular weight and polymer chain endgroups. The apparent activation energy of isothermal crosslinking was independent of molecular weight and chain endings. Its value of 60 kcal/mole is the same as that for the thermal degradation of PPQ (determined by isothermal weight loss measurements). The rates of change of Tg at a particular temperature, however, are a function of both molecular weight (at least for these polymers that do not have a sufficiently high molecular weight) and the type of polymer chain ends. It was observed that isothermally crosslinked PPQ gave a higher break point in the TGA curve and also an increased char yield at 800°C than the linear precursor.  相似文献   

20.
通过在4,4′-二氨基二苯醚(4,4-′ODA)单体中引入三氟甲基合成了一种新型二胺单体2-三氟甲基-4,4′-二氨基二苯醚(3FODA),该单体具有良好的溶解性和高的反应活性,使用3FODA替代4,4′-二氨基二苯甲烷(MDA)制备了PMR热固性聚酰亚胺树脂.树脂溶液高浓度低粘度,具有室温下良好的储存稳定性;树脂具有很好的加工性能,成型后的模压件显示了优异的热性能和耐热氧化稳定性,玻璃化转变温度在336~379℃之间;此外树脂具有较好的电性能和较低的吸水率.  相似文献   

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