共查询到20条相似文献,搜索用时 56 毫秒
1.
2.
3.
以4,4′-(六氟异丙烯)二酞酸酐(6FDA)为含氟二酐,4,4′-二氨基-2,2′-双三氟甲基联苯(TFMB)为含氟二胺,通过引入分子结构相对对称的刚性单体1,2,4,5-均苯四甲酸二酐(PMDA)进行共聚合成了5种含氟比例不同的透明聚酰亚胺薄膜,并对其性能进行了表征。分析表明:引入刚性单体共聚后薄膜的热稳定性和耐热性有所提高;薄膜的介电常数随着PMDA含量的上升而增加;共聚薄膜在可见光领域的透光率低于均聚薄膜;拉伸实验显示在添加少量PMDA后,薄膜的拉伸强度和弹性模量有所增大,但当PMDA含量过高时其力学性能反而下降;随着PMDA含量的增加,薄膜的热膨胀系数明显降低。 相似文献
4.
本文介绍了以TFDB二胺为基础同6FDA、DMDA二酐聚合的均聚和共聚的含氟PI的特性,并研究了它们的组成与其性能之间的关系。均聚和共聚含氟PI的低的光损耗和能控制的折射率在用于制作光电元器件中是最重要的特性,特别在波长为近红外区为13μm或155μm的电信通讯中。 相似文献
5.
本文通过PMDA与二种不同二胺共处次制得了七种三元共聚聚酰亚胺膜,并对其透气性进行了初步探讨。 相似文献
6.
通过分子设计制备一种新型二胺单体3,3'-二异丙基-4,4'-二氨基二苯基-4″-氟苯基甲烷(PAFM)及新型可溶性含氟聚酰亚胺薄膜材料(FPIs)。研究表明,聚合物溶解性能显著,能较好溶于常规有机溶剂,如N,N-二甲基甲酰胺(DMF)、N,N-二甲基乙酰胺(DMAc)、二甲亚砜(DMSO)、N-甲基吡诺烷酮(NMP)、四氢呋喃(THF)和丙酮;耐热性能突出,玻璃化转变温度高于273℃,氮气中10%热失重温度在470℃以上;光学性能优良,截止波长低于322 nm,波长大于466 nm范围内透过率都在80%以上;疏水性能优异,接触角超过90.8°。 相似文献
7.
三元共聚型光敏聚酰亚胺的合成及性能研究 总被引:1,自引:0,他引:1
采用均苯四酸二酐(PMDA)分别与4,4'-二氨基二苯醚(ODA)、3,3,-二甲基联苯胺(DMPA)、二氨基二苯砜(DDS)进行三元共聚,合成了一系列光敏聚酰亚胺(PSPI).采用IR、TGA、XRD等测试手段对共聚物的结构与性能进行了表征和研究.实验结果表明:3种共聚型PSPI均可溶于强极性溶剂,其特性黏数在1.08~1.38dL/g.热稳定性依次降低,其顺序为PSPI(Ⅰ)>PSPI(Ⅲ)>PSPI(Ⅱ).XRD测试结果发现,PSPI(Ⅱ)的结晶倾向最弱. 相似文献
8.
以4,4'-二氨基-2,2'-双三氟甲基联苯(TFMB)、4,4'-(六氟异丙烯)二酞酸酐(6FDA)和3,3',4,4'-联苯四甲酸二酐(BPDA)为反应单体,改变非含氟BPDA单体在二酐中的配比和加料方式制备出一系列共聚型含氟聚酰亚胺(PI)薄膜并表征和分析其性能,研究了共聚物链结构对其性能的影响。结果表明,BPDA单体的加料方式及其在二酐单体中的比例均影响薄膜的性能。共聚型含氟PI薄膜在室温下均溶于非质子极性溶剂,且在可见光范围内有较高的透光率。随着非含氟二酐单体BPDA含量的提高薄膜的光学性能略有降低而其热性能和力学拉伸性能提高。非含氟二酐单体占二酐单体的比例为68.97%的共聚型PI薄膜,在500 nm处的透过率达到96.01%;非含氟二酐单体占二酐单体比例为35.71%的共聚型PI薄膜失重10%的热分解温度为595.23℃,拉伸强度为100.98 MPa。同时,BPDA加料方式的改变对共聚型PI薄膜的光学性能、热学性能和力学拉伸性能均有不同程度的影响。 相似文献
9.
用4-苯基-2,6-双[3-(4-氨基-2-三氟甲基苯氧基)苯基]吡啶(m,p-6FPAPP)作为二胺,3,3′,4,4′-二苯酮四甲酸二酐(BTDA)及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,合成了可溶性含氟聚酰亚胺。用FT-IR、DSC、TGA、UV-vis、溶解性和吸水率测试对聚合物的结构和性能进行了表征。结果表明,FT-IR测试在1780 cm-1、1720 cm-1和1380 cm-1左右出现了聚酰亚胺的特征吸收峰。所得聚酰亚胺在常见溶剂(如间甲酚,DMF,N,N-二甲基乙酰胺(DMAc),二甲基亚砜(DMSO),N-甲基吡咯烷酮(NMP),四氢呋喃(THF))中可溶解;在氮气氛中,玻璃化转变温度(Tg)为202.1℃~219.7℃,10%失重温度为537.0℃~572.8℃,800℃质量保持率为60.7%~63.1%。PI膜的紫外截止波长为375 nm~380 nm,吸水率为0.55%~0.63%。 相似文献
10.
用4,4′-二氨基二苯醚(ODA)作为二胺,3,3′,4,4′-二苯醚四羧酸二酐(ODPA)及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,合成了可溶性共聚聚酰亚胺。用红外光谱(FT-IR)、差示扫描量热(DSC)、热重分析(TG... 相似文献
11.
Heat-resistant flexible-film optical waveguides were fabricated from fluorinated polyimides. These waveguides operated in single mode and had low optical loss (0.3 dB/cm) at a wavelength of 1.3 mum for TE and TM polarizations. They also had good flexibility: The optical loss did not significantly change above a minimum radius of curvature of less than 20 mm. The birefringence of 9 x 10(-5) between the TE and TM polarizations is 2 orders of magnitude smaller than that for a waveguide upon a substrate. Moreover, these waveguides had high thermal stability and moisture resistance: The optical loss and single-mode behavior changed little after heating the waveguides at 420 degrees C for 1 h or after their exposure to 85% relative humidity at 85 degrees C for more than 350 h. 相似文献
12.
Buried channel optical waveguides were fabricated from fluorinated polyimides. They operated in single mode and showed an optical loss of less than 0.3 and 0.7 dB/cm for TE and TM polarizations, respectively, at a wavelength of 1.3 mum. Moreover, these waveguides had high heat and moisture resistance; the optical loss did not significantly change after heating at 380 degrees C for 1 h or after exposure to 85% relative humidity at 85 degrees C for over 200 h. 相似文献
13.
14.
Man He Yuming Zhou Yafeng Gao Yongjuan Wang Xiaohai Bu Tao Zhang Yiping Cui Tong Zhang 《Journal of Materials Science》2013,48(9):3370-3377
A branched structure bichromophore was developed to increase the nonlinearity of optical polymers. The branched bichromophore was incorporated into the polymer backbone to prepare a novel nonlinear optical (NLO) side-chain fluorinated polyimide with high optical nonlinearity and good thermal stability. The novel nonlinear optical side-chain fluorinated polyimide exhibits a large electro-optic (E-O) coefficient (γ33) (34 pm/V at 1550 nm) which is larger than that of the conventional side-chain optical polyimide. This is mainly attributable to an increased chromophore concentration and high polarizing efficiency derived from the branched structure. The branched structure of the bichromophore is incorporated into a polymer backbone to result in a high chromophore concentration. Moreover, the three-dimensional (3D) architecture and large molecular size of the branched bichromophore can spatially shield from strong interchromophore electrostatic interactions to enhance the poling efficiency. The side-chain fluorinated polyimide exhibits excellent solubility in common organic solvents, good film-forming property, high glass-transition temperature (T g) (190 °C) and thermal stability up to 235 °C. 相似文献
15.
16.
17.
18.
Mariana-Dana Damaceanu Radu-Dan Rusu Maria Bruma 《Journal of Materials Science》2012,47(16):6179-6188
This study focuses on the thermal, photo-optical and electrochemical characterization of some copoly(oxadiazole-naphthylimide)s containing tetramethyldisiloxane units. The thermal stability and glass transition temperatures of these copolymers were measured and compared with those of related polymers. The polymers were processed in very thin films having smooth surfaces, without pinholes or cracks. Upon irradiation with UV light the polymers showed photoluminescence maxima in the blue spectral range. Cyclic voltammetry was performed to obtain information about the electrochemical stability and reversibility of the redox processes of these polyimides. The HOMO and LUMO energy levels, and electrochemical and optical band gap values were calculated by using cyclic voltammetry and UV–Vis spectroscopy data, showing very good electron-injection and transport characteristics. These properties make the present polymers suitable for application in electroluminescent devices. 相似文献
19.
20.
Qing Li Jing Li Guangfu Liao Zushun Xu 《Journal of materials science. Materials in medicine》2018,29(8):126
1,3,5-Tris(4-aminophenoxy) benzene (TAPOB) and 2,2-bis [4-(3,4-dicarboxyphenoxy) phenyl] propane dianhydride (BPADA) were used to synthesize an amino-terminated hyperbranched polyimide (AM-HBPI). Then, the 2-methacryloyloxyethyl phosphorylcholine-modified hyperbranched polyimide (HBPI-MPC) was obtained through the graft modification of MPC onto AM-HBPI by Michael addition. The infrared spectroscopy and X-ray photoelectron spectroscopy spectra showed MPC molecules were successfully grafted onto the HBPI molecules. The HBPI-MPC films exhibited slightly decreased thermal stabilities with 5% weight loss temperature in the range of of 418–483?°C in nitrogen, compared with the pure HBPI film. With the increase of MPC grafting amount, the static water contact angles decreased from average 84.0° of the pure HBPI film to average 45.0° of the HBPI-MPC film with 20% MPC. Meanwhile, the increased surface roughness of the HBPI-MPC films increased the contact areas with the platelets, enhancing their anticoagulant efficiency. The number of platelet adhesion declined and the shape of platelet changed from flat to round. The recalcification times grew from average 300?s of pure HBPI to average 551?s of the HBPI-MPC film with 20% MPC, indicating improved anticoagulant properties and biocompatibility. Bacterial adhesion test also demonstrated the number of bacterial adhesion was significantly reduced and antibacterial properties were improved. Thus, the HBPI-MPC films have great application prospects as biomedical anticoagulant materials. 相似文献