首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 100 毫秒
1.
用4-苯基-2,6-双(4-氨基苯基)吡啶作为二胺,3,3′,4,4′-二苯醚四羧酸二酐和双酚A型二酐作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,分别经热亚胺化和化学亚胺化过程合成了3种聚酰亚胺。用傅里叶变换红外光谱对聚合物的结构进行表征,表明在1 780,1 720,725cm-1附近出现了聚酰亚胺的特征吸收峰。采用溶解性测试、X射线衍射、热重分析、拉伸测试和吸水率测试表征了产物性能。所合成的共聚聚酰亚胺溶解性较好,溶于常见有机溶剂。所合成的聚酰亚胺膜热稳定性良好,在氮气氛中,起始降解温度超过500℃,10%失重温度为547.1~601.5℃,800℃质量保持率为64.8%~67.2%。聚酰亚胺膜的拉伸强度、拉伸模量、断裂伸长率分别为105.8~112.6 MPa,2.24~2.32 GPa,9.5%~10.2%。膜的吸水率为0.96%~0.98%。  相似文献   

2.
用2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)和4-苯基-2,6-双(4-氨基苯基)吡啶(PBAP)作为二胺,3,3′,4,4′-二苯醚四羧酸二酐(ODPA)作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,分别经热亚胺化和化学亚胺化合成了3种聚酰亚胺。用傅里叶变换红外光谱和核磁共振氢谱表征聚合物的结构,结果表明在1 780,1 720,725 cm~(-1)附近出现了聚酰亚胺的特征吸收峰。采用热重分析,溶解性、拉伸性能和吸水率测试表征了产物性能。所合成的聚酰亚胺溶解性和热稳定性良好,在N_2气氛中,起始降解温度超过500℃;800℃质量保持率为46.2%~64.5%(化学亚胺化)和52.6%~64.8%(热亚胺化)。聚酰亚胺膜的拉伸强度、拉伸断裂应变、拉伸模量分别为107.2~109.6 MPa,7.8%~10.5%,2.13~2.28 GPa。膜的吸水率为0.68%~0.75%。  相似文献   

3.
用2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)及3,5-二氨基苯甲酸(DABA)作为二胺,2,2-双[4-(3,4-二羧基苯氧基)苯基]丙烷二酐(BPADA)作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,分别经热亚胺化和化学亚胺化过程合成了可溶性共聚聚酰亚胺。用FT-IR对聚合物的结构进行了表征,性能测试采用了溶解性测试、DSC、TGA、拉伸测试和吸水率测试。FT-IR图谱表明,在1 780cm~(-1)、1720 cm~(-1)和740 cm~(-1)左右出现了聚酰亚胺的特征吸收峰。共聚聚酰亚胺在常见有机溶剂中可溶,并且有很好的热稳定性,玻璃化转变温度T_g为226.5℃,在氮气氛中降解起始温度508.5℃,800℃质量保持率为46.5%。共聚聚酰亚胺膜的拉伸强度、拉伸模量、断裂伸长率分别为109.7MPa、2.25GPa和15.2%。  相似文献   

4.
以邻甲酚酞与2-氯-5-硝基三氟甲苯为起始原料,通过两步有机反应——芳香亲核取代和氧化还原反应得到芳香二胺单体——4,4"-(2,2’三氟甲基)-二氨基苯氧基-3,3"-二甲基酚酞。利用共聚改性的思路,由两种二胺单体〔4,4"-(2,2"三氟甲基)-二氨基苯氧基-3,3"-二甲基酚酞和2,6-二氨基甲苯〕与一种二酐单体3,3",4,4"-二苯醚四甲酸二酐(ODPA)通过不同投料比以一步法高温缩聚制备得到同时含酚酞、三氟甲基和烷基结构系列共聚型聚酰亚胺。该系列共聚型聚酰亚胺具有优异的溶解性,在室温下不仅可溶于常见的高沸点溶剂:N-甲基吡咯烷酮(NMP),N,N-二甲基乙酰胺(DMAc)、N,N-二甲基甲酰胺(DMF)和二甲基亚砜(DMSO),在低沸点溶剂氯仿(CHCl3)、二氯甲烷(CH2Cl2)和四氢呋喃(THF)中也表现出优异的溶解性,可便利地通过其溶液浇筑制备得到系列高性能聚酰亚胺膜材料。该类膜材料玻璃化转变温度在275~314 ℃,其在N2和O2氛围中热失重10%时的温度分别为477~507 ℃和477~49 0 ℃。该类膜材料具有低的介电常数和良好的力学性能:其在1 MHz下介电常数在2.69~2.92之间,拉伸强度、弹性模量和断裂伸长率分别在80~92 MPa、1.2~1.8 GPa和9.2 %~13.5%之间。  相似文献   

5.
用2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)和4-苯基-2,6-双(4.氨基苯基)吡啶(PBAP)作为二胺,3,3’,4,4'-二苯酮四酸二酐(BTDA)作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,合成了3种聚酰亚胺。先用BAPP和PBAP同BTDA反应生成一系列聚酰胺酸(PAA),然后将得到的PAA用化学亚胺化制备相应的聚酰亚胺。用FT-IR、^1H—NMR、粘度测试、溶解性测试和TGA对聚合物的结构和性能进行了表征。结果表明,FT—IR测试在1780cm^-1、1720cm^-1和725cm^-1左右出现了聚酰亚胺的特征吸收峰,所得聚酰胺酸的特性粘数为0.32~0.46dL/g,大部分聚酰亚胺在常见有机溶剂NMP中可溶,它们有很好的热稳定性,氮气氛中,在500℃以前没有明显的降解。  相似文献   

6.
化学亚胺化法合成三元共聚聚酰亚胺   总被引:1,自引:0,他引:1  
以N,N-二甲基甲酰胺为溶剂,用3,3′,4,4′-二苯酮四酸二酐(BTDA)、2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)和4,4′-二氨基二苯砜(DDS)合成3种聚酰亚胺(PI)。先用BAPP和/或DDS与BTDA反应生成一系列聚酰胺酸(PAA),然后将得到的PAA化学亚胺化制备相应的PI。用傅里叶变换红外光谱(FTIR)仪、核磁共振仪和黏度计等表征了聚合物的结构和性能。FTIR谱图中1780,1720,725 cm~(-1)附近出现了PI的特征吸收峰。制备的PI有很好的热稳定性,N_2气氛中低于500℃没有明显的降解。  相似文献   

7.
以N,N-二甲基乙酰胺为溶剂,用芳香族二胺4,4′-二氨基二苯醚(ODA)与不同比例的2个芳香族二酐4,4′-联苯四甲酸二酐(BPDA)、双酚A型二醚二酐(BPADA)制备三元共聚无氟芳香族透明聚酰亚胺(PI)薄膜。用傅里叶变换红外光谱仪(FTIR)表征PI结构,用差示扫描量热仪(DSC)、热重分析仪(TG)、阻抗分析仪、紫外-可见分光光度仪(UV-VIS)研究PI薄膜的热性能、介电性能和透光率。结果表明:三元共聚PI薄膜玻璃化转变温度高于210.0℃;热失重5%的温度高于480.0℃;在可见光范围内透明性良好,PI薄膜在465 nm处透光率均超过80.0%,最高可达85.5%;相对介电常数为1.728 1~2.987 2,介电损耗为0.002 9~0.014 3。  相似文献   

8.
以2,6-二氨基甲苯、3,3'',4,4''-联苯四甲酸二酐、3,3'',4,4''-二苯醚四甲酸二酐为原料,间甲酚作为溶剂,经一步法高温共缩聚,制备一系列可溶性共聚型聚酰亚胺(MPI)。利用红外光谱(FTIR)、核磁共振波谱(1H NMR)、差式扫描量热仪(DSC)、热重分析仪(TGA)和紫外-可见光分度计(UV)等测试仪器对MPI进行结构与性能表征。结果表明:红外与核磁的数据说明成功合成了含甲基结构的聚酰亚胺;该系列的含甲基聚酰亚胺在室温下可溶于N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAc)、二氯甲烷(CH2Cl2)三氯甲烷(CHCl3)、二甲基亚砜(DMSO)等有机溶剂,具有良好的溶解性和成膜性,并随着联苯酐的含量增加溶解性降低;同时该系列MPI制得的薄膜具有良好的光学透过性能,在紫外光波长450 nm时的透过率均在74%以上,截止波长在350 nm左右;该系列MPI的起始分解温度均大于457 ℃,800 ℃氮气氛围中的焦炭产率均大于63%,玻璃化转变温度在260 ℃~285 ℃之间,表现出优异的热学性能。此外,MPI-1~MPI-4薄膜还具有良好的机械性能,其弹性模量在1.7~2.1 GPa,拉伸强度在89.7~120.6 MPa,断裂伸长率在19.7%~28.4%。  相似文献   

9.
蔡华娟  耿凯  汪称意  李坚  任强 《精细化工》2023,40(6):1287-1293
以百里香酚酞、对氟硝基苯为起始原料,通过芳香亲核取代和氧化还原反应得到新型芳香二胺单体5,5’-二异丙基-4,4’-二氨基苯氧基-2,2’-二甲基酚酞。该二胺单体分别与3,3’,4,4’-二苯醚四甲酸二酐、3,3’,4,4’-二苯酮四羧酸二酐和3,3’,4,4’-联苯四甲酸二酐以一步法高温缩聚制得了一系列同时含酚酞Cardo结构及异丙基和甲基侧基的高可溶性聚酰亚胺(PI-1、PI-2和PI-3)。该系列聚酰亚胺具有优异的溶解性,室温下不仅可溶于高沸点溶剂N-甲基吡咯烷酮、N,N-二甲基乙酰胺、N,N-二甲基甲酰胺、二甲基亚砜,而且能溶于低沸点溶剂氯仿,二氯甲烷和四氢呋喃,可通过其溶液浇铸制得一系列高性能聚酰亚胺薄膜。所制聚酰亚胺薄膜具有较高的光学透明性,截断波长在324~365 nm之间,450 nm的透过率在56%~78%之间。该系列薄膜玻璃化转变温度在266~289℃之间,在N2和O2下10%热失重温度均≥432℃。其拉伸强度在77~95 MPa之间,断裂伸长率在9.1%~13.0%之间,1 MHz下介电常数为2.79~3.01 F/m,...  相似文献   

10.
可溶性聚酰亚胺的链结构设计   总被引:1,自引:0,他引:1  
本文综述制备可溶性聚酰亚胺的最新方法,并讨论高分子链结构对聚合物溶解性能的影响。  相似文献   

11.
以3,3’-二氨基二苯砜(DDS)和4,4’-二氨基二苯醚(ODA)作为共缩聚二胺单体,与3,3’,4,4’-二苯酮四羧酸二酐(BTDA)进行缩合聚合,合成了一系列具有一定溶解性的共聚酰亚胺。采用升温红外光谱监控了聚酰胺酸热环化为聚酰亚胺的过程,对所得产物的热稳定性和力学性能进行研究,发现二胺单体的组成对共聚酰亚胺的性能产生较为明显的影响。  相似文献   

12.
Copolyimides were synthesized from dianhydride of 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with various diamine contents of 4,4′‐oxydianiline (ODA) and 2,3,5,6‐tetramethyl‐1,4‐phenylenediamine (TeMPD) by chemical imidization in a two‐step procedure. Polyimides (PIs) were characterized using thermogravimetric analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, as well as specific volume and free volume. The gas transport properties for pure gas and blends of CO2 and CH4 for the homopolymers and 6FDA‐ODA/TeMPD copolymers were investigated at 35°C and 150 psi pressure. In pure gas permeation, permeability of CO2 and CH4 increased with increasing TeMPD content in the diamine moiety, whereas the ideal selectivity decreased with increasing TeMPD content. In the mixed gas permeation, permeabilities and separation factor were measured as a function of CO2 feed molar fraction for five PI membranes. The behavior of pure gas and mixed gas permeabilities and separation factor of CO2/CH4 mixtures as the chemical nature of the diamine and the CO2 molar fraction in the feed gas were varied and are discussed in detail. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013  相似文献   

13.
以3-羟基苯乙酮和苯甲醛为原料,通过改进的Chichibabin反应制备了4-苯基-2,6-双(3-羟基苯基)吡啶(m-PHPP),再将其与2-氯-5-硝基三氟甲苯反应,合成了硝基化合物4-苯基-2,6-双[3-(4-硝基-2-三氟甲基苯氧基)苯基]吡啶(m,p-6FPNPP),最后用Pd/C和水合肼将m,p-6FPN...  相似文献   

14.
New polyamic acids with ‐A‐B‐A‐C‐ type periodic sequence of monomeric units (A derived from a diamine, B from benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride, and C from benzene‐1,2,4,5‐tetracarboxylic dianhydride) are prepared and transformed into polyimide membranes that are examined by various methods in order to investigate the influence of diamine units (aliphatic, alicyclic, or aromatic) on the morphology, thermal stability, and mechanical properties of membranes. Small‐ and wide‐angle X‐ray scattering and Atomic force microscopy show amorphous character of all membranes except for those containing hexane‐1,6‐diamine units. Thermogravimetric analysis reveals a decrease in the initial decomposition temperature from 551/501 °C to 437/395 °C (for N2/O2 atmosphere) when going from membranes with aromatic to those with aliphatic diamine units. Dynamic mechanical analysis shows quite high initial storage modulus (2100–3300 MPa) for all membranes at frequencies of 1, 10, and 20 Hz. The properties of prepared copolymeric polyimide are promising for a wide range of their potential technological applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45227.  相似文献   

15.
采用二胺1,2—二氢—2—(4—氨基苯基)-4—[4—(4—氨基苯氧基)—苯基卜二氮杂萘—1—酮(二胺A)、对苯二胺为共缩聚二胺单体,与对苯二甲酸在Yamazaki膦酰化法聚合体系中,选择直接缩聚法,成功得到高分子量的聚芳酰胺,其特性粘数为0.96~1.44dL/g。以傅里叶变换红外光谱、核磁共振氢谱等分析手段研究了聚合物的结构,利用差示扫描量热法、热失重分析研究了聚合物的耐热性能。结果表明,该系列聚合物具有高的玻璃化转变温度(约为300℃),氮气氛中5%热失重温度在450℃以上;当二胺A与对苯二胺的物质的量比例为10:0—5:5时,所得聚合物溶解于强极性溶剂。同时,系统研究了影响聚合物特性粘数的诸多因素,从而确定了最佳工艺条件。  相似文献   

16.
A series of bismaleimide monomers with amide groups were prepared and characterized. Structurally different bismaleimides (with amide units) were synthesized by a reaction between 4‐maleimidobenzoyl chloride and various diamines. The monomers were characterized by infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and elemental analysis. The thermal characterization of the bismaleimides was accomplished with differential scanning calorimetry and dynamic thermogravimetric analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 567–572, 2006  相似文献   

17.
Three random and two block 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA)-based copolyimides with different 6FpDA:Durene molar ratio varying from 25 to 80% were prepared and characterized. The pure-gas permeation data of their membranes were investigated at 100 psi and 22 °C. The CO2/CH4 ideal selectivity coefficient increased to around 47 with the increase of the 6FpDA content to 80% in the copolymer backbone while the CO2 permeability coefficient found to be the highest (378 barrer) with highest Durene content copolymer. Based on its attractive pure-gas permeation properties(CO2/CH4 = 47), 6FDA-6FpDA/6FDA-Durene (4:1) block copolyimide was selected for further analyses, where the effect of pressure and temperature on its gas transport properties was evaluated. Furthermore, the mixed-gas permeation properties were investigated using multicomponent sweet and sour gas mixtures prepared from N2 (30% or 10%), CH4 (59%), C2H6 (1%), CO2 (10%), and H2S (0% or 20%)accordingly. The sweet mixed-gas CO2/CH4 selectivity and CO2 permeability coefficients of 6FDA-6FpDA/6FDA-Durene (4:1) are around 39 and 45 barrer, respectively, at elevated pressure (800 psi). The polymer, however, showed nonideal behavior when subjected to high H2S-content gas mixture (20 vol. % H2S), where the CO2/CH4 selectivity value dropped to around 21 and the H2S/CH4 selectivity coefficient is 13. The CO2 and H2S permeability coefficients are 42 and 26 barrer, respectively, at an upstream pressure up to 500 psi. When plotted on the combined acid gas permeability-selectivity curve, the polymer separation efficiency was nearby the high-performing polymers reported in the literature, and way superior to the industrial standard glassy polymer, cellulose acetate, used currently in gas separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48336.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号