聚酰亚胺纤维增强环氧树脂结构透波复合材料的性能研究及机制分析

选择聚酰亚胺纤维和环氧树脂,采用热熔法制备出了聚酰亚胺/环氧结构透波复合材料。通过傅里叶变换红外光谱、吸湿率、力学性能、介电性能、湿热老化性能以及扫描电子显微镜等表征手段,研究了聚酰亚胺/环氧结构透波复合材料的结构透波性能和耐湿热环境性能。研究结果表明：聚酰亚胺纤维中刚性共轭结构赋予了聚酰亚胺纤维复合材料良好的透波性能和耐湿热性能,但是与石英纤维增强环氧树脂复合材料相比,聚酰亚胺纤维增强环氧树脂结构透波复合材料仍存在着压缩强度、弯曲强度与层间剪切强度低、吸湿率高的问题;力学性能破坏模式分析结果显示,聚酰亚胺纤维同时存在有机纤维的吸湿、压缩强度低、纤维/树脂界面结合差的问题。     

高性能聚酰亚胺复合材料的研究进展

综述了国内外高性能聚酰亚胺复合材料的研究进展,主要包括以双马来酰亚胺树脂、反应型聚酰亚胺(PMR型聚酰亚胺)树脂及乙炔基封端聚酰亚胺树脂作为基体材料的复合材料,也包括以聚酰亚胺纤维作为增强体的复合材料,针对结构与性能的关系以及材料的性能优化进行了介绍,并对聚酰亚胺复合材料的发展方向进行了展望.     

聚酰亚胺-聚苯胺复合材料的制备

主要研究聚酰亚胺-聚苯胺复合材料的制备，并用二探针法标定聚酰亚胺-聚苯胺的导电性，及采用热分析法检验聚酰亚胺-聚苯胺复合材料的热稳定性。     

高介电聚酰亚胺复合材料的制备及应用

随着电子工业的不断发展,传统的聚酰亚胺材料作为电子电工领域应用较多的绝缘介质材料,人们对其综合性能要求也越来越高.目前,聚酰亚胺的复合材料在生活领域中广泛应用,有关高介电常数的聚酰亚胺复合材料薄膜的研究也越来越多.不同类型的线性电介质、导电填料、介电陶瓷加入聚酰亚胺基体,可以得到介电常数不同的聚酰亚胺复合材料.本文列举...     

几个高性能树脂基复合材料的研究

介绍了短纤维增强树脂基复合材料、聚酰亚胺纳米杂化薄膜材料和环氧基纳米复合材料方面的研究工作，简要概括了短玻璃纤维、短碳纤维以及与颗粒混合增强树脂基复合材料的研究结果，报道了聚酰亚胺纳米杂化薄膜材料和环氧基纳米复合材料的一些低温性能研究结果。     

热塑性聚酰亚胺复合材料在航空航天中的应用

热塑性聚酰亚胺具有突出的耐高温性能和优异的机械性能,是目前树脂基复合材料中耐温性最高的材料之一.简述了几种常用的热塑性聚酰亚胺树脂,详细介绍了热塑性聚酰亚胺及其复合材料在太阳帆、太阳电池阵和飞机中的应用,简要介绍了国内研究热点及动态.     

碳纤维／聚酰亚胺耐高温复合材料成型工艺及其性能的研究

本文研究了碳纤维／聚酰亚胺复合材料的成型工艺及其力学性能和高温力学性能以及热学性能，指出了评价耐高温复合材料的长期耐热性和短期耐热性的方法，为用户制作了碳纤维／聚酰亚胺耐高温复合材料产品，并通过了高温试验。     

纳米粒子改性聚酰亚胺现状及进展

由于聚酰亚胺(PI)材料存在亲水性较弱、加工成型性较难、电导率较低等缺陷，需要通过纳米粒子改性聚酰亚胺改善其性能。基于不同纳米粒子改性聚酰亚胺，综述并评论了国内外聚酰亚胺纳米复合材料的研究现状，阐述了有机纳米粒子(CNC、FEP)、无机纳米粒子(陶瓷材料、金属纳米粒子、蜂窝芯材)、有机-无机纳米粒子(POSS、MWCNTs-COOH、OGO)复合改性聚酰亚胺性能的原理和效果，分析了聚酰亚胺复合杂化过程中面临的问题和改进方法，结合目前聚酰亚胺复合材料发展集中在合成工艺改进、填料优化改性等方面的研究趋势，提出了聚酰亚胺未来的研究方向。     

含硅聚酰亚胺的合成与性能

含硅聚酰亚胺由于具有可溶性、粘合性、吸湿性以及电绝缘性等方面的优势,近年来逐渐成为聚酰亚胺改性研究的热点。本文主要综述了近年来主链型含硅聚酰亚胺、侧链型含硅聚酰亚胺以及聚酰亚胺含硅无机复合材料的合成方法及其改性性能,并对含硅聚酰亚胺的研究发展进行了展望。     

聚酰亚胺/无机纳米粒子复合材料在介电领域应用

传统的聚酰亚胺材料的介电常数范围通常在3. 0～3. 6之间,是电子电工领域应用较多的绝缘介质材料。随着相关行业技术的不断发展,对聚酰亚胺材料的要求也越来越高。目前,具有高介电常数的聚酰亚胺复合材料薄膜正越来越多地被人们研究。通过向聚酰亚胺体系内加入不同类型的无机纳米粒子,可以不同程度低提高聚酰亚胺体系的介电常数。本文列举了不同类型无机纳米粒子掺杂的聚酰亚胺复合材料的制备及表征工作,并对其应用进行了展望。     

含氟聚酰亚胺的研究及其在涂料中的应用

介绍了含氟聚酰亚胺的分类和研究动向,重点介绍了含三氟甲基及六氟丙基的聚酰亚胺的特点和性能。阐述了含氟聚酰亚胺在绝缘涂料中的应用,并对含氟聚酰亚胺在光电材料、复合材料和气体分离膜等领域中的应用进行了概述。     

Influence of chemical structure of polyimide prepolymer on rheo‐mechanical properties of polyimide foam composites

A study is reported of the effect of varying chemical composition of foam polyimide prepolymers (H‐complex) on the structure and properties of foam polyimide resins and their composites with aromatic polyimide fiber felt. The melt rheological behavior of the H‐complex was found to be strongly dependent on its chemical composition and structure reorganization in the melt which is akin to mesophasic structural transition states in liquid crystal polymers. Changing the diamine part of the H‐complex from 4,4‐methylene dianiline to 1,3‐diaminobenzene led to decreased steady shear viscosity at temperatures and shear rates ranging between 95° and 105°C and 0.01 and 1 s⁻¹, respectively. Additionally, changing the dialkyl moiety from dimethyl to diethyl in 3,3′,4,4′‐benzophenonetetracarboxylic dialkyl ester (precursor to the H‐complex) increased gelation time of the H‐complex, enhancing processibility of the foam polyimide composites. The results indicate that novel, lightweight foam polyimide composites with enhanced thermomechanical properties for beneficial uses can be prepared through chemical modification of the H‐complex prior to its thermal imidization in the presence of the aromatic polyimide fiber felt.     

In situ preparation of polyimide/titanium carbide composites with enhanced dielectric constant

A series of polyimide/titanium carbide (PI/TiC) composites with different TiC contents were prepared using the ultrasonic dispersion and in situ polymerization method. Atomic force microscopy (AFM), X‐ray diffraction (XRD), scanning electron microscope (SEM), mechanical, and electrometer were used to characterize the structure and properties of the obtained composites. The morphological study of composites by AFM and SEM showed that TiC particles had a homogeneous dispersion in polyimide matrix with nanoscale at low filler dosage (≤10% volume content). X‐ray diffractions (XRDs) indicated that the doping of TiC slightly reduced the packing density of polyimide and destructed the aggregation structure of polyimide molecules. Experimental results showed that the obtained PI/TiC composites exhibited appropriate mechanical properties and moderate electric breakdown strength. Dielectric investigation evidenced that the dielectric constant and the dielectric loss of these composites increased with the increase of the volume fraction of TiC particles. The composite with 20 vol% TiC particles showed a highest dielectric constant of 37 while retaining an appropriate dielectric loss of 0.026, as compared with the dielectric constant (3–4) of neat polyimide resin. In addition, the dielectric properties of the composites displayed good stability within a wide range of frequency. The results of this work demonstrate the potential use of a PI/TiC composite film in an embedded capacitor. POLYM. COMPOS., 125–130, 2016. © 2014 Society of Plastics Engineers     

三维碳纤维机织物增强PMR型聚酰亚胺复合材料的成型与性能研究

使用PMR型聚酰亚胺预聚物溶液和三维碳纤维机织物预制件制作了三维机织物增强PMR型聚酰亚胺复合材料。通过对制备的PMR型聚酰亚胺预聚物的红外特征光谱(FT-IR)的分析和熔融流变性能的测试,设计优化了一种"两步浸渍热压法"制作三维机织物增强PMR型聚酰亚胺基复合材料,对复合材料的内部结构、热性能以及力学性能进行了表征与测试。     

Carbon/carbon composites based on a polyimide matrix with coal tar pitch

Blending of coal tar pitch with a polyimide precursor based on acetyl derivatives of aromatic diamines during its synthesis leads to a homogeneous, highly thermostable matrix for carbon fibre reinforced composites. If the weight content of the pitch in the polyimide matrix does not exceed 40%, the mechanical properties (flexural strength, shear modulus and fracture toughness) of these composites are comparable to those of similar composites based on a pure polyimide matrix. Carbonisation and graphitisation of the composites with a properly blended matrix precursor leads to carbon fibre reinforced carbon composites with lower open porosity and higher density, elastic modulus and flexural strength than those of composites based on a pure polyimide matrix.     

Modeling of the mechanical properties of nanoparticle/polymer composites

A continuum-based elastic micromechanics model is developed for silica nanoparticle/polyimide composites with various nanoparticle/polyimide interfacial treatments. The model incorporates the molecular structures of the nanoparticle, polyimide, and interfacial regions, which are determined using a molecular modeling method that involves coarse-grained and reverse-mapping techniques. The micromechanics model includes an effective interface between the polyimide and nanoparticle with properties and dimensions that are determined using the results of molecular dynamics simulations. It is shown that the model can be used to predict the elastic properties of silica nanoparticle/polyimide composites for a large range of nanoparticle radii, 10-10,000 Å. For silica nanoparticle radii above 1000 Å, the predicted properties are equal to those predicted using the standard Mori-Tanaka micromechanical approach, which does not incorporate the molecular structure. It is also shown that the specific silica nanoparticle/polyimide interface conditions have a significant effect on the composite mechanical properties for nanoparticle radii below 1000 Å.     

Graphite Filler-Based Nanocomposites with Thermoplastic Polymers: A Review

This up-to-date review comprehends the research performed on three important types of thermoplastic polymers, i.e., polyamide, polyimide, and poly(amide-imide). Graphite has been discussed as indispensable nanofiller to form significant categories of polyamide/graphite, polyimide/graphite, and poly(amide-imide)/graphite nanocomposite. Main focus of this review was to outline the properties and potential of these polymers and their composites. Studies have demonstrated considerable enhancement in the strength, thermal, electrical, rheology, and wear properties of these polymers upon graphite addition. Significance of polyamide, polyimide, poly(amide-imide), and graphite-based composites have been discussed keeping in view the challenges and future demands for contemporary technical applications.     

Influence of structure of amines on the properties of amines‐modified reduced graphene oxide/polyimide composites

Graphene oxide (GO), as an important precursor of graphene, was functionalized using alkyl‐amines with different structure and then reduced to prepare reduced amines grafted graphene oxide (RAGOs) by N₂H₄ · H₂O. The successful chemical amidation reaction between amine groups of alkyl‐amines and carboxyl groups of GO was confirmed by Fourier transform infrared (FTIR), X‐ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA). Then RAGOs/polyimide nanocomposites were prepared via in situ polymerization and thermal curing process with different loadings of RAGOs. The modification of amine chains lead to homogenous dispersion of RAGOs in the composites and it formed strong interfacial adhesion between RAGOs and the polymer matrix. The mechanical and electrical properties of polyimide (PI) were significantly improved by incorporation of a small amount of RAGOs, the influence of structure of amines grafted on RAGOs on the enhancement effects of composites was discussed. The research results indicated that the proper structure of amine could effectively enhance the properties of composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43820.     

国内耐高温聚酰亚胺树脂及其复合材料专利分析

本文对国内有关聚酰亚胺复合材料技术的公开专利进行了检索分析。主要从年度专利申请量、申请人所属国专利申请量、职务状况专利申请量、专利申请类别分布、法律状态、主要申请人专利申请数量和技术分类专利申请量概况等7个方面进行了数据整理,了解了耐高温聚酰亚胺树脂及其复合材料技术方面的知识产权现状,明确了该技术的研究热点并展望了其发展趋势。