具有网络互穿结构的木质陶瓷复合材料

提出以新型环境材料多孔木质陶瓷（WCMs)为骨架，用真空压力浸渍工艺制备了WCMs／金属网络互穿结构复合材料，并研究了材料的性能，结果表明，复合材料浸渍效果良好，组织均匀且网络互穿结构明显，与基体木质陶瓷比较，复合材料的导热性能和力学性能都得到明显改善，组成相的互锁和韧性相的桥接作用可能是材料性能改善的主要机制。     

不饱和聚酯/聚氨酯互穿网络聚合物基玻璃纤维增强材料的研究

研究了以不饱和聚酯/聚氨酯互穿网络聚合物为基的玻璃纤维复合材料的动态热机械性能及应用性能.结果表明,在不饱和聚酯树脂中加入5%～10%的聚氨酯,使基质形成互穿网络,有利于提高由此得到的复合材料的性能.     

三维连续网络结构陶瓷／金属复合材料的研究进展

总结了国内外三维连续网络结构陶瓷／金属复合材料及其多孔陶瓷预制件在制备工艺方面的研究现状,分析了各种工艺的特点,介绍了这种新型复合材料在力学性能、热学性能、摩擦磨损性能、减震性能等方面的研究成果,并展望了三维连续网络结构陶瓷／金属复合材料的应用前景及其发展趋势。     

新型三元互穿聚合物网络阻尼材料的研制

采用平衡溶胀工艺,合成了具有宽温域、高阻尼值的新型三元互穿聚合物网络。透射电镜证明了乳液交联反应的发生和互穿网络的结构。分别通过对乳液及乳胶膜性能的测试和比较,发现三元互穿聚合物网络相容性和阻尼性均优于二元互穿聚合物网络。     

压电陶瓷/CIIR复合材料的阻尼性能的研究

以氯化丁基橡胶(CIIR)及其互穿网络为基体,加入压电陶瓷PMN和导电炭黑CB制备PMN/CB/CIIR复合材料,系统研究其的阻尼性能的影响因素以及机理,以获得高介电常数和高阻尼性能的压电陶瓷/聚合物基复合材料,拓展其在介电材料和阻尼材料领域的应用。     

不饱和聚酯／聚氨酯互穿网络聚合物基玻璃纤维增强 …

研究了以不饱和聚酯／聚氨酯互穿网络聚合物为基的玻璃纤维复合材料的动态热机械性能及应用性能。结果表明,在不饱和聚酯树脂中加入５％－１０％的聚氨酯,使基质形成互秀利于提高由此得到的复合材料的性能。     

纤维素/聚氨酯半互穿网络的制备及性能

利于聚氨酯对纤维素进行改性研究,介绍了纤维素/聚氨酯半互穿网络的制备方法,并利用红外光谱（FT-IR）、扫描电子显微镜（SEM）、X射线衍射（XRD）、力学性能及电学性能的测试对纤维素/聚氨酯半互穿网络的特征进行研究。结果表明,在半互穿网络中纤维素和聚氨酯具有明显的相分离现象;线性纤维素分子穿插于已交联的聚氨酯网中,形...     

复合材料的摩擦学性能研究获新进展

中国科学院兰州化学物理研究所先进润滑与防护材料研发中心在聚氨酯/环氧树脂互穿聚合物网络(PU/EPIPN)复合材料的摩擦学性能研究方面取得新进展。PDMS具有较高的热、氧化稳定性和良好的抗湿性能。在前期工作中,研究人员发现HTPDMS改性后的PU/EPIPNs复合材料呈现出良好的阻尼、热和机械性能,可被用作结构阻尼材料。该材料的     

基于人造海绵的碳/环氧树脂网络互穿复合材料的制备及磨损性能研究

采用人造海绵为模板,通过浸渍酚醛树脂和环氧树脂,制备了具有海绵构造的碳/环氧树脂网络互穿复合材料。并研究了该复合材料的微观形貌及摩擦磨损性能。结果发现人造海绵的网络状构造很好地复制到了复合材料中。与环氧树脂相比,复合材料的磨损率和摩擦系数都降低了。复合材料中的网状碳限制了环氧树脂基体的应变和回弹能力,使其摩擦系数变动范围变小。显示出此类复合材料具有更加稳定的摩擦磨损性能。     

聚苯胺用量对镍粉/环氧树脂多功能复合材料分散行为和机械性能的影响研究

对掺杂聚苯胺(PAN)的导电性能、结构及其加入量对镍粉/环氧树脂复合体系的分散和机械性能进行研究。十二烷基苯磺酸比盐酸掺杂的PAN导电性更优良归因于其对PAN链更大的离域作用。由于互穿网络的形成,PAN的加入提高了镍粉在环氧树脂中的分散均匀性;同时提高了复合材料的机械性能     

A micromechanical model for interpenetrating multiphase composites

The dependence relation between the macroscopic effective property and the microstructure of interpenetrating multiphase composites is investigated in this paper. The effective elastic moduli of such composites cannot be calculated from conventional micromechanics methods based on Eshelby’s tensor because an interpenetrating phase cannot be extracted as dispersed inclusions. Employing the concept of connectivity, a micromechanical cell model is presented for estimating the effective elastic moduli of composites reinforced with either dispersed inclusions or interpenetrating networks. The model includes the main features of stress transfer of interpenetrating microstructures. The Mori–Tanaka method and the iso-stress and iso-strain assumptions are adopted in an appropriate manner of combination, rendering the calculation of effective moduli quite easy and accurate.     

Effective Elastic and Plastic Properties of Interpenetrating Multiphase Composites

In interpenetrating phase composites, there are at least two phases that are each interconnected in three dimensions, constructing a topologically continuous network throughout the microstructure. The dependence relation between the macroscopically effective properties and the microstructures of interpenetrating phase composites is investigated in this paper. The effective elastic moduli of such kind of composites cannot be calculated from conventional micromechanics methods based on Eshelby's tensor because an interpenetrating phase cannot be extracted as dispersed inclusions. Using the concept of connectivity, a micromechanical cell model is first presented to characterize the complex microstructure and stress transfer features and to estimate the effective elastic moduli of composites reinforced with either dispersed inclusions or interpenetrating networks. The Mori–Tanaka method and the iso-stress and iso-strain assumptions are adopted in an appropriate manner of combination by decomposing the unit cell into parallel and series sub-cells, rendering the calculation of effective moduli quite easy and accurate. This model is also used to determine the elastoplastic constitutive relation of interpenetrating phase composites. Several typical examples are given to illustrate the application of this method. The obtained analytical solutions for both effective elastic moduli and elastoplastic constitutive relations agree well with the finite element results and experimental data.     

原位反应渗透法TiCp/Mg复合材料的制备和性能

利用Ti和C元素粉末间的原位放热反应合成TiCp,结合Mg熔体的自发渗透技术制备了TiCp/Mg以及TiCp/AZ91D两种镁基复合材料,观测了复合材料的相组成和原位反应生成物TiCp的形貌,研究了这两种镁基复合材料的常温压缩性能.结果表明,原位反应自发渗透技术制备的Mg基复合材料组织致密,增强相呈细小的颗粒状和互穿网片状,分布均匀.这是材料的压缩强度得到提高的原因.在常温以及应变速率为0.01 s-1的条件下,TiCp/Mg和TiCp/AZ91D镁基复合材料的压缩强度分别达到598和650 MPa.     

Processing,microstructure, and physical properties of interpenetrating Al2O3/Ni composites

Abstract

Alumina/nickel composites have been fabricated by hot pressing powder blends of various volume fractions of nickel and alumina. The electrical resistivities and Young's moduli of these composites have been measured and their dependence on the volume fraction of reinforcement has been investigated. Microstructural parameters such as contiguity were measured to quantify the distribution of the phases in these composites, and existing property models based on these data were used to predict the properties of the composites. The percolation threshold of nickel was found to occur at between 7.5 and 15 vol.-%Ni. The Young's modulus decreases as the volume fraction of nickel increases and is dependent on the contiguity of alumina. Composites containing 25, 35, 50, and 65 vol.-%Ni display microstructures with interpenetrating networks of alumina and nickel. The property models were found to fit both the resistivity and modulus data well, although the percolation threshold was predicted at a lower volume fraction than measured experimentally.     

Preparation and characterization of interpenetrating phased TCP/HA/PLGA composites

The purpose of this study was to fabricate composites consisting of three interpenetrating networks: tricalcium phosphate (TCP), hydroxyapatite (HA), and poly(dl-lactide-co-glycolide) (PLGA). The porous TCP network was first produced by coating a polyurethane (PU) foam with hydrolysable alpha-TCP slurry. The HA network was derived from a calcium phosphate cement (CPC) filled in the porous TCP network. The remaining open pore network in the HA/TCP composite was further infiltrated with a PLGA network. The three sets of spatially continuous networks would have different biodegradation rates and thus bone tissue would grow towards the fastest biodegrading network while the remaining networks still maintaining their geometrical shape and carrying the physiological load for the tissue ingrowth.     

Interpenetrating polymer networks of polyurethane and epoxy

Interpenetrating polymer networks of polyurethane, based on poly(oxypropylene)triol grafted with polyacrylonitrile and epoxy, were prepared by a simultaneous polymerization technique. The mechanical properties and morphology of the networks were investigated. As the epoxy content increased, the tensile strength of the interpenetrating polymer networks or the graft networks (in which some grafting reaction has taken place between polyurethane and the pendant hydroxyl group of epoxy) decreased. The shifts of the loss modulus peaks of the interpenetrating polymer networks and the graft-IPNs were different and their tan peaks shifted to a high temperature as the epoxy content increased.     

Intrinsically stretchable transparent electrodes based on silver-nanowire-crosslinked-polyacrylate composites

Stretchable transparent composites have been synthesized consisting of a silver nanowire (AgNW) network embedded in the surface layer of a crosslinked poly(acrylate) matrix. The interpenetrating networks of AgNWs and the crosslinked polymer matrix lead to high surface conductivity, high transparency, and rubbery elasticity. The presence of carboxylic acid groups on the polymer chains enhances the bonding between AgNWs and the polymer matrix, and further increases the stretchability of the composites. The sheet resistance of the composite electrode increases by only 2.3 times at 50% strain. Repeated stretching to 50% strain and relaxation only causes a small increase of the sheet resistance after 600 cycles. The morphology of the composites during reversible stretching and relaxation has been investigated to expound the conductivity changes.     

细菌纤维素/聚乳酸互穿网络复合材料的结晶与熔融

为了研究细菌纤维素(BC)网络结构对聚乳酸(PLA)结晶与熔融过程的影响,以PLA为基体,BC为增强体,通过PLA-三氯甲烷溶液与BC-无水乙醇分散液的共混扩散制备了具有互穿网络结构的BC/PLA生物复合材料。采用SEM、偏光显微镜(POM)、DSC和莫志深(MO)模型研究了复合材料的微观形态、球晶形貌、非等温结晶动力学和熔融行为。结果表明:采用溶液共混扩散法可得到以BC为骨架、PLA缠绕其表面的互穿网络结构的复合材料。随降温速率增加,BC/PLA复合材料的结晶温度、熔融温度和相对结晶度均下降。BC可作为异相成核剂,适量添加可同时提高BC/PLA复合材料的结晶速率和相对结晶度,细化球晶尺寸。MO模型可较好地描述BC/PLA复合材料的非等温结晶动力学行为。     

Mechanical properties and thermal ageing of a perfluoroether-modified epoxy resin in castings and glass fibre composites

Castings from a bisphenol epoxy resin cured with methyl nadic anhydride, and containing varying amounts of a miscibilized carboxy-terminated perfluoroether oligomer (CTMF), were produced in such a manner as to display two different morphologies: one consisting of fine heterophase interpenetrating networks (IPNs) and the other comprising precipitated dispersed particles. High-temperature accelerated ageing showed that compositions containing 15% CTMF exhibit higher flexural strength and ductility than unmodified resins, irrespective of the type of morphology. Castings of CTMF-modified resin with an IPN morphology, however, displayed superior property retention characteristics with respect to thermal ageing and consequently were chosen as the matrix for the production of unidirectional fibre composites. The composites, on the other hand, were found not to exhibit the same improvements in heat ageing resistance as the castings. The cause has not been established but the increase in peak tan δ temperature over that exhibited by the castings suggests that the matrix is more highly crosslinked.