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聚酰亚胺/无机纳米杂化材料的研究 总被引:6,自引:1,他引:5
聚酰亚胺(PI)中引入无机纳米粒子,可弥补PI的性能缺陷(如较高的热膨胀系数和较低的吸水性),非常适合对PI改性.本文阐述了PI纳米杂化材料的制备方法,介绍了纳米杂化材料的特点及应用. 相似文献
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《高分子材料科学与工程》2012,(1):4-4
本发明提供了一种聚酰亚胺/无机纳米杂化材料制备方法,首先合成适用于聚酰亚胺的无机纳米粒子改性剂——亚胺环基硅烷;采用溶胶-凝胶法制备无机氧化物纳米粒子,在溶胶一凝胶反应过程中加入改性剂亚胺环基硅烷,得到有机-无机复合体纳米颗粒;将有机-无机复合体纳米颗粒均匀分散于聚酰胺酸溶液中,经过加热处理得到聚酰亚胺/无机纳米杂化材料。本发明的聚酰亚胺/无机纳米杂化材料制备方法解决了纳米粒子分散的难题,在聚酰亚胺/无机纳米杂化材料中纳米粒子分布均匀,不团聚,有利于其各项性能的充分发挥。 相似文献
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《高分子材料科学与工程》2012,(1):4+8+15+18+25+29+62+66+70+78+131+142+167+183
专利名称:聚酰亚胺/无机纳米杂化材料制备方法专利申请号:CN200710072263.3公开号:CN101058673申请日:2007.05.28公开日:2007.10.24申请人:哈尔滨工程大学本发明提供了一种聚酰亚胺/无机纳米杂化材料制备方法,首先合成适用于聚酰亚胺的无机纳米粒子 相似文献
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采用溶胶-凝胶法制备了SiO2及A12O3溶胶,并将其掺入到聚酰胺酸基体中,得到无机纳米SiO2-Al2O3/聚酰亚胺杂化膜,并对其结构性能进行了研究.实验表明,薄膜材料中无机纳米SiO2和Al2O3粒子分散均匀,与有机相存在键合;材料热分解温度有所提高. 相似文献
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采用溶胶-凝胶法制备纳米二氧化硅及氧化铝溶胶,将溶胶混合后掺入正在反应的聚酰胺酸中,制得聚酰亚胺/二氧化硅-氧化铝杂化薄膜。利用扫描电子显微镜对杂化薄膜的微观形貌进行了表征,并测试了无机组分含量不同的杂化薄膜的力学性能、热稳定性及介电性能。试验结果表明,杂化薄膜材料中无机相呈现纤维结构和颗粒结构,有效地提高了薄膜的力学性能。杂化薄膜与纯膜相比,热分解温度有较大提高,且随着无机组分含量增大,热分解温度呈现先上升后下降的趋势。介电性能分析表明,杂化薄膜的介电常数和介电损耗与频率的关系符合德拜松弛极化机理。 相似文献
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杂化聚酰亚胺薄膜无机相形貌和介电性能研究 总被引:1,自引:0,他引:1
采用溶胶-凝胶法制备纳米二氧化硅及氧化铝溶胶,将其掺入聚酰胺酸溶液中,制得聚酰亚胺/二氧化硅-氧化铝杂化薄膜,利用原子力显微镜对杂化薄膜的无机相微观形貌进行表征,用精密阻抗分析仪测试杂化膜介电性能.研究表明:掺入无机组分含量均为4%时,随着掺入二氧化硅所占比例的增大,无机纳米粒子的平均粒径增加,当其与氧化铝质量比为8:1时无机相呈网络状,与聚酰亚胺基体界面模糊;掺入无机组分对杂化薄膜的介电性能产生影响,介电常数ε和介电损耗tgδ随频率增加而减小,在相同频率下随掺入二氧化硅所占比例增大,介电常数ε和介电损耗tgδ增大. 相似文献
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以4-苯乙炔苯酐和γ-氨丙基三乙氧基硅烷为原料,设计并合成新型耐热硅烷偶联剂-3-[(4-苯基乙炔基)邻苯二甲酰亚胺基]丙基三乙氧基硅烷(PEIPTES),并通过13C NMR和FT-IR对产物进行了表征.PEIPTES能溶解在DMF、DMSo等有机溶剂中,并具有较好的耐热性能,氮气中热失重10%的温度为532℃.由于PEIPTES的特殊分子结构,既能与无机相形成化学键,又与聚酰亚胺具有较好的相容性,因此通过PEIPTES对SiO2前驱体的原位改性,将PEIPTES应用到聚酰亚胺杂化膜中,制备无机相以纳米尺度均匀分散的聚酰亚胺杂化膜. 相似文献
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Nanocomposites with tunable coefficient of thermal expansion (CTE) were prepared by incorporating cubic zirconium tungstate (ZrW2O8) nanoparticles at various volume percentages in a polyimide (PI). Rod-shaped nanoparticles of cubic ZrW2O8, which has isotropic negative thermal expansion, were synthesized using a hydrothermal method. The interfacial interaction between the PI and ZrW2O8 was enhanced by covalently bonding different organic moieties, including a short aliphatic silane and PI oligomer, to the surface of ZrW2O8. Structure–property relationships for the PI–ZrW2O8 nanocomposites were investigated for thermal degradation, glass transition, tensile and thermal expansion properties. Addition of ZrW2O8 nanoparticles did not alter the thermal degradation and glass transition temperature of the base PI. The addition of ZrW2O8 nanoparticles increased the Young's modulus of the polymer, indicating stiffening of the polyimide matrix. The increase was higher for nanocomposites with engineered interfaces due to the efficient load transfer achieved through the presence of linker groups. The addition of ZrW2O8 reduced the in-plane CTE of the base PI at all loadings studied. The CTE of the base PI was reduced by around 22% with the addition of ZrW2O8 at 15 volume% loading. 相似文献
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以耐高温型聚酰亚胺为基体,微米碳化硼(B_4C)为热中子吸收剂,采用粉体表面改性及超声湿混-热亚胺化成膜工艺成功制备了一系列B_4CP/PI聚酰亚胺复合薄膜,重点探讨了不同B_4C含量条件下复合薄膜的耐热性能和力学性能以及不同B_4C含量、不同复合薄膜厚度条件下复合材料的热中子屏蔽性能。研究表明:采用上述工艺,B_4C功能粒子在聚酰亚胺基体中可均匀分散;B_4CP/PI复合薄膜的耐热性随B_4C含量的增加显著提高,力学性能则呈相反趋势;所制备的B_4CP/PI复合薄膜表现出优异的热中子屏蔽性能,中子透射率I/I0随复合薄膜厚度增加及B_4C含量增加呈指数变化规律。据此,可通过材料结构设计,满足不同领域对该类耐高温中子防护材料的应用需求。 相似文献
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A series of colorless and transparent polyimide (PI) nanocomposite films was synthesized from 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and bis(3-aminophenyl) sulfone (APS) with various organoclay contents via solution intercalation polymerization to poly(amic acid)s, followed by thermal imidization. Varying the organoclay loading in the range of 0 to 1.00 wt% produced variations in the thermal properties, morphologies, and optical transparencies of the hybrids. The hybrid films exhibited high optical transparencies and almost no color, with cut-off wavelengths between 330 and 346 nm and very low yellow index (YI) values of 1.78-3.80. The hybrid PI films showed good thermal properties with glass transition temperatures of 236-245 degrees C. Most films did not show significant thermal decomposition below 450 degrees C. It was found that the addition of only a small amount of organoclay was sufficient to improve the thermal properties of the PI films, with maximum enhancements being observed at 0.50 wt% organoclay. Moreover, these PI hybrids also showed low coefficients of thermal expansion (CTE). 相似文献
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Fiber-reinforced composites are widely used in the design and fabrication of a variety of high performance aerospace components. The mismatch in coefficient of thermal expansion (CTE) between the high CTE polymer matrix and low CTE fiber reinforcements in such composite systems can lead to dimensional instability and deterioration of material lifetimes due to development of residual thermal stresses. The magnitude of thermally induced residual stresses in fiber-reinforced composite systems can be minimized by replacement of conventional polymer matrices with a low CTE, polymer nanocomposite matrix. Zirconium tungstate (ZrW(2)O(8)) is a unique ceramic material that exhibits isotropic negative thermal expansion and has excellent potential as a filler for development of low CTE polymer nanocomposites. In this paper, we report the fabrication and thermal characterization of novel, multiscale, macro-nano hybrid composite laminates comprising bisphenol E cyanate ester (BECy)/ZrW(2)O(8) nanocomposite matrices reinforced with unidirectional carbon fibers. The results reveal that incorporation of nanoparticles facilitates a reduction in CTE of the composite systems, which in turn results in a reduction in panel warpage and curvature after the cure because of mitigation of thermally induced residual stresses. 相似文献
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Colorless and organo-soluble polyimide (PI) films have been synthesized from an alicyclic dianhydride BCDA and aromatic diamine 3,4′-ODA in the cosolvent of DMAc and GBL via one-step process. The graphene oxide (GO) was mixed with the above PI in DMAc solution to fabricate the PI/GO nanocomposite films. With the addition of only 0.001 wt% of GO in PI matrix, the resultant nanocomposite (PI/GO-0.001) exhibits not only the enhanced resistance to moisture but also retains superior visible light transmission, enhanced mechanical strength, and excellent dimensional stability, simultaneously. The water-vapor-transmission-rate (WVTR) significantly reduced to 30 g mil m−2 day−1 for this nanocomposite compared to 181 g mil m−2 day−1 for pure PI. Notably, the PI/GO-0.001 nanocomposite also exhibits low coefficient of thermal expansion (CTE) of 41 ppm °C−1, which is benefited from the homogeneous distribution of ultrathin GO nanosheets in PI matrix. 相似文献
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Sebastián Suárez Flavio Soldera Carlos González Oliver Diego Acevedo Frank Mücklich 《Advanced Engineering Materials》2012,14(7):499-502
The thermal expansion behavior of Ni matrix composites reinforced with multiwalled carbon nanotubes (MWNT) fabricated by pressureless sintering and hot uniaxial pressing was studied in the range between 50 and 1050 °C and compared to that of pure Ni. The results show an active interaction between the MWNT and the Ni matrix by reducing the coefficient of thermal expansion (CTE) of pure Ni up to 76% between 50 and 400 °C. This reduction is due to the strong interfacial interaction between the matrix and the reinforcement and the low intrinsic CTE of the nanotubes. This outstanding behavior may be very useful in applications were low CTE is required as for example structural materials. 相似文献
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Xin Mao Wenfeng Guo Chengzhang Li Jie Yang Lirong Du Xianzhong Tang 《Journal of Materials Science: Materials in Electronics》2017,28(5):4088-4094
All-organic polyimide (PI)/poly(vinylidene fluoride) (PVDF) composite materials with high dielectric constant and low dielectric loss were fabricated via solution blending. The dielectric, mechanical, and thermal properties of the PI/PVDF composite films were studied. Results indicated that the dielectric properties of the composites were highly reinforced through the introduction of PVDF, and the composites exhibited excellent thermal stability. When the mass fraction of PVDF was adjusted to 30 wt%, the specimen demonstrated excellent thermal properties, superior mechanical properties, high dielectric constant (5.7, 1 kHz), and low dielectric loss (0.009, 1 kHz). Moreover, the dependence of the dielectric constant and dielectric loss on frequency was investigated. The composite presented stable dielectric constant and dielectric loss that were less than 0.04 within the testing frequency range of 100 Hz–10 MHz. This study demonstrated that the PI/PVDF composites were potential dielectric materials in the field of electronics. 相似文献
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Xiuyu Wang Tongning Chen Mingxiu Li Bonan Ding Yanpeng Liu Hao Zhang Jianwen Liao 《Journal of Materials Science: Materials in Electronics》2017,28(7):5215-5221
The polyimide/CaMoO4 nanocomposites were successfully prepared by ex-situ polymerization. (3-Aminopropyl) triethoxysilane (KH550) was used as coupling agent to disperse the CaMoO4 nanoparticles in polyimide matrix homogeneously. To characterize the structure and properties of the obtained nanocomposites, Scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, dielectric properties and thermal stability were studied. It was observed that the CaMoO4 nanoparticles were dispersed homogeneously in the polyimide matrix without obvious aggregation. The results show that nano-sized CaMoO4 will improve dielectric constant and decrease dielectric loss of the nanocomposites in the relatively high-frequency region (>10 kHz). And the nanocomposite with excellent dielectric properties of ε?=?3.04, δ?=?8.0?×?10?3 was obtained after doping 2.5 wt% nano-sized CaMoO4 into polyimides. Dielectric loss of the nanocomposites is reduced in low frequency domain (<10 kHz) and enhanced in high frequency domain (>10 kHz). In addition, the thermal stability of the nanocomposites was enhanced from 544 to 651?°C compared to pure polyimide. 相似文献
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表面改性纳米TiO2粒子杂化PI薄膜的制备与性能研究 总被引:1,自引:0,他引:1
采用硅烷偶联剂(γ-巯丙基三乙氧基硅烷)对纳米TiO2粒子进行表面处理,通过原位聚合和流延成膜法制备了不同TiO2含量的PI/TiO2杂化膜,研究了杂化膜的热性能、力学性能,并通过扫描电镜(SEM)和广角X衍射(WAXD)研究了杂化膜的微观形貌结构,同时也对杂化膜的接触角和介电常数(ε)进行了研究分析.结果表明,杂化膜较纯膜的热分解温度(T5%)降低,但平均热分解温度仍然高于520℃,且膜的尺寸稳定性得到了提高,即热膨胀系数( CTE)降低;表面形貌分析表明,1%~5%的表面改性纳米TiO2能较好地分散在PI膜里,杂化膜的介电常数(3.50左右)均高于纯膜的的介电常数(2.91),杂化膜的接触角随着TiO2含量的增加呈现先减少后增加的趋势. 相似文献