电子束固化树脂基复合材料进展

综述了电子束固化树脂基复合材料的树脂基体、电子束固化工艺的优越性、吵固化复合材料在国内外的发展状况以不固化复合材料中存在的一些待解决的问题。     

天然植物纤维的改性与树脂基复合材料

对如象黄麻，亚麻，木材纤维，棉等十余种天然纤维的物理和化学改性方法以及将其应用于树脂基复合材料的性能作了系统的评述。     

树脂基硅灰石复合材料的研究进展

我国是硅灰石资源大国，硅灰石在各种树脂中有广泛的应用。影响树脂基硅灰石复合材料性能的因素有很多，本文从聚合物基体和硅灰石填料两个方面对国内外部分树脂基硅灰石复合材料的研究成果进行了综述，探讨了硅灰石增强增韧聚烯烃的方法和机理，并追踪了国内外的最新研究动态。     

磁性树脂基复合材料的研究进展

综合磁性树脂基复合材料的研究现状,着重介绍了磁性树脂基复合材料的三大类：粘结磁体、磁性高分子微球和磁性离子交换树脂的最新发展和研究状况。     

硅炔杂化树脂改性有机硅树脂及其复合材料的性能

用一种硅炔杂化树脂聚（甲基硅烷-二乙炔基苯）（PSP）改性有机硅树脂（HS）,通过FT—IR和TGA研究了树脂体系的固化反应及耐热性,并对制备的复合材料进行力学性能、耐热性能和介电性能研究。结果表明：当HS与PSP的质量比为5：5时综合性能最优,树脂体系在氮气氛围下质量损失5％时的温度（T幽）为691℃,1000℃时质量保留率为88％;HS—PSP树脂短切玻纤复合材料冲击强度为21kJ／m^2,弯曲强度为65MPa,200℃时的弯曲强度高温保留率为78％,介电常数为4．6,介电损耗因数为7．9×10,体积电阻为6．7×10^13Ω。改性后的复合材料具有优异的力学、耐热和介电性能。     

热塑性树脂的增强：从原位复合材料到原位混杂复合材料

综述了两类增强的热塑性树脂的基本方面。一类是由原位形成的热致液晶聚合物微纤增强的原位复合材料。从实验上研究了获得有效增强效果的两个关键因素；致热液晶聚合物的基体树脂中的成纤，以及在液晶聚合物与基体树脂不相容共混物中的增容作用。另一类是由作者发明的原位混杂复合材料，这一类材料是用直径在两个数量级上的纤维和原位形成的微纤混杂增强的。     

玄武岩纤维增强树脂基复合材料界面改性策略

近年来,工业界和学术界都将注意力聚焦在可持续天然纤维复合材料的开发上。玄武岩纤维具有高强度、高模量、耐高温、耐酸碱、隔热隔音、热振稳定性好、介电性能优异、绿色无污染及成本低等优点,玄武岩纤维增强树脂基复合材料凭借其优异的机械性能和可设计性被广泛地应用于飞行器、汽车、船舶、建筑、石油化工管道及风力发电机叶片等领域。然而,玄武岩纤维与聚合物基底间差的相容性导致玄武岩纤维增强树脂基复合材料存在诸多缺陷和不足。其中,界面强度不够高、界面相易被破坏的问题成为制约玄武岩纤维增强树脂基复合材料发展的瓶颈之一,因此许多玄武岩纤维增强树脂基复合材料研究工作集中在提高其界面结合能力上。本文介绍了玄武岩纤维增强树脂基复合材料的主要研究方向,以及几种常见的复合材料界面作用机理,并综述了近年来国内外关于玄武岩纤维增强树脂基复合材料界面增强改性方面的研究工作。     

耐高温可溶性聚酰亚胺树脂及其复合材料

制备了2种耐高温可溶型聚酰亚胺树脂(PI-1, PI-2)及其复合材料, 系统研究了树脂的工艺性, 纯树脂固化物的热性能及其复合材料的界面形貌、 介电性能和力学性能. 研究结果表明, 树脂低聚物在极性非质子溶剂中具有良好的溶解性, 且熔体黏度较低, 表明其具有优异的加工性能. 两种树脂固化物在空气中的5%热失重温度均高于550 ℃, PI-1树脂的玻璃化转变温度(T_g)为430 ℃, PI-2树脂的T_g为380 ℃. 石英纤维/PI-1和石英纤维/PI-2复合材料具有较低的介电常数和介电损耗. 碳纤维/PI-1复合材料在420 ℃下的弯曲强度保持率可达62%, 层间剪切强度保持率可达48%, 具有较优异的高温力学性能. 采用普通模压工艺制备了厚度高达45 mm的复合材料制件, 进一步证明这2种树脂具有优异的工艺性.     

纤维增强树脂基复合材料多相结构特征对材料性能的影响

综述了纤维复合材料结构和性能的关系,着重介绍界面对复合材料宏观力学性能的影响。     

Phenylethynyl-terminated Imide Oligomers Modified by Reactive Diluent for Resin Transfer Molding Application

To meet the processing requirements of resin transfer moulding(RTM)technology,reactive diluent containing m-phenylene moiety was synthesized to physically mixed with phenylethynyl terminated cooligoimides with well-designed molecular weights of 1500-2500 g/mol derived from 4,4’-(hexafluoroisopropylidene)diphthalic anhydride(6 FDA),3,4’-oxydianiline(3,4’-ODA)and m-phenylenediamine(m-PDA).This blend shows low minimum melting viscosity(<1 Pa·s)and enlarged processing temperature window(260–361℃).FPI-R-1 stays below 1 Pa·s for2 h at 270℃.The relationship between the molecular weight of the blend and its melting stability was first explored.Blending oligoimides with lower molecular weights exhibit better melting stability.Upon curing at 380℃for 2 h,the thermosetting polyimide resin demonstrates superior heat resistance(T_g=420-426℃).     

RTM用苯乙炔封端聚(甲基次乙炔基硅烷)树脂的流变特性

以可用于RTM成型的含硅炔杂化树脂体系为研究对象,深入研究了树脂体系的流变特性,并根据双阿仑尼鸟斯方程,建立了流变修正模型,该模型可揭示树脂在不同温度下的黏度行为.研究表明:恒温与动态条件下的树脂流变行为符合阿仑尼鸟斯流变模型,模型的计算结果和实验测试结果吻合得较好.     

不饱和聚酯片状模塑料的模压成型与性能

采用模压成型的方法制备了不饱和聚酯片状模塑料(UP-SMC)制品,通过万能试验机、热重分析、动态热机械分析、氧指数和纳米压痕技术研究了制品的力学性能、热稳定性能和阻燃性能。 结果表明,UP-SMC制品的弯曲强度和冲击强度分别达到203.4和94.2 MPa,由树脂过渡到纤维的各相微观力学性能是不同的。 该制品的玻璃化转变温度为169.4 ℃,在N₂气气氛下失重5 %(T_d5)和最大失重速率(T_dmax)对应的温度分别为333.5和389.7 ℃,600 ℃的质量保留率大于75%,极限氧指数为25.7%,表明该UP-SMC制品具有优异的力学性能和热稳定性能。     

Fabrication of Patterned Conducting Polymers on Insulating Polymeric Substrates by Electric‐Field‐Assisted Assembly and Pattern Transfer

Summary: The use of electrostatically addressable templates for the directed assembly of conducting polymers and pattern transfer to another polymer substrate is demonstrated. Doped conducting polyaniline was selectively assembled on the patterned template assisted by a DC electric field. Adding an insulated silicon dioxide layer onto the surface of the silicon wafer is critical to the formation of patterned PANi rather than a PANi film. After deposition, it was demonstrated that by compression molding or solution casting methods, patterned PANi can be completely transferred to a secondary polymer substrate, such as an NBR sheet or a polyurethane film. The conductivity of PANi lines on the PU film was found to be as high as 0.87 S · cm⁻¹. The simple one‐step assembly process for patterning conductive polymers and transfer provides a promising nanomanufacturing approach for cost‐effective and high performance flexible nanoelectronics and biosensors.

Optical image of PANi‐assembled templates with patterned gold lines connected to negative electrodes at 10 V for 1 min.     

Practical and Theoretic Analysis of Resin Flow in Vacuum Assisted Resin Transfer Molding Processes

In this study, the non-isothermal resin infiltration during the VARTM process has been analyzed and characterized. In particular, the resin flow through the fibers has been described by the Darcy law and introducing the degree of saturation, the percent of void effectively occupied by the resin within a control volume, as variable in order to account for the moving boundary nature of the problem. Some preliminary tests to measure the advancement of a reference substance, pure water, between the reinforcement fibers with embedded optic fibers sensors, show the capability of a new sensorial technology, based on use of non intrusive fiber optic COTS components, assembled into an original way. These sensors will be used for real time monitoring of the resin flow during the experimental infusion tests and for in-situ demonstration of the capability and the reliability of the model, in the aim to assure a “process repeatability”. Due the effectiveness lack of repeatability of VARTM, the Authors propose an approach to extract a parameter during the process, meaning a “Deviation” of modelized output (MOD Modelized Output Deviation). This parameter, obtained by use of optic fibers technology, may improve the standard quality of the production, analyzing and correcting with feed-back capability the efficiency of the moulded manufactured devices.     

Reprogrammable Chemical 3D Shaping for Origami,Kirigami, and Reconfigurable Molding

Origami- and kirigami-based design principles have recently received strong interest from the scientific and engineering communities because they offer fresh approaches to engineering of structural hierarchy and adaptive functions in materials, which could lead to many promising applications. Herein, we present a reprogrammable 3D chemical shaping strategy for creating a wide variety of stable complex origami and kirigami structures autonomously. This strategy relies on a reverse patterning method that encodes prescribed 3D geometric information as a spatial pattern of the unlocked phase (dispersed phase) in the locked phase (matrix phase) in a pre-stretched Nafion sheet. Building upon the unique chemical reprogramming capability of the Nafion shape memory polymer, we have developed a reconfigurable molding technology that can significantly reduce time, costs, and waste by shaping various 3D materials with high fidelity.     

NEURAL NETWORK ANALYSIS APPLICATION TO PERMEABILITY DETERMINATION OF FIBERGLASS AND CARBON PREFORMS

Preform permeability is an important process parameter in liquid injection molding of composite parts.This parameter is currently determined with time consuming and expensive experimental procedures.This paper presents the application of a back-propagation neural network to predicting fiber bed permeability of three types of reinforcement mats. Resin flow experiments were performed to simulate the injection cycle of a resin transfer molding process.The results of these experiments were used to prepare a ...     

聚合物反应注射成型

本文简要地介绍了反应注射成型(RIM)的发展,RIM的化学体系,RIM过程和制品的成型,RIM过程的主要特点及RIM聚氨酯的主要组分。     

Effect of Layering Pattern on the Mechanical Properties of Bark Cloth (Ficus natalensis) Epoxy Composites

The quest for sustainable materials as a consequence of a global drive to mitigate climate change has led to a focus on natural fiber–reinforced composite materials. In this study, skillful ply angle arrangement of bark cloth–reinforced laminar epoxy composites was carried out for the first time using vacuum-assisted resin transfer molding, and the composites fabricated were characterized for the effect of the layering pattern on their static and dynamic mechanical properties. Tensile strength and flexural strength were shown to be dependent on the ply angle arrangement. Dynamic mechanical analysis of the composites showed a glass transition temperature of 70°C, and the storage modulus and mechanical damping properties showed that the developed composites can withstand considerable loads and have excellent fiber-to-matrix adhesion.