树脂传递模塑成型用高性能双马来酰亚胺改性树脂基体的研究

本文以烯丙基对甲酚醚（ＡＭＰＥ），作为双马来酰亚胺（ＢＭＩ）／二烯丙基双酚Ａ（ＤＡＢＰＡ）树脂体系的活性稀释剂，获得了适合树脂树脂传递成型（ＲＴＭ）工艺的三元共聚树脂体系。通过对该树脂体系及其固化物的粘度－温度－时间曲线，凝胶化特性、ＤＳＣ（微分扫描式量热）ＩＲ（红外光谱）、ＳＥＭ（电子显微镜扫描）和力学性能测试，表明该体系在ＲＴＭ成型 中，注射温度可取７０℃，该温度下，粘度仅０．３Ｐａ．ｓ，贮存     

RTM工艺专用混合型树脂体系研究--热性能与力学性能研究

本文对乙烯基酸树脂和环氧树脂共混改性的ＲＴＭ工艺专用脂体系及其复合材料性能进行研究,共混树脂体系ＲＴＭ工艺复合材料的动态机构性能,拉伸及冲击性能研究结果表明,混合型树脂体系的复合材料耐热及力学性能接近或达到环氧树脂体系的性能,成本却比环氧树脂纸１／３以上,采用不同树脂体系的共混改性方法是研究和开发具有良好工艺性、耐热性和力学性能的低成本ＲＴＭ工艺树脂体系的有效途径。     

RTM专用混合型树脂体系研究——反应特性与工艺特性研究

本文采用乙烯基酯树脂和环氧树脂体系共混改性的方法。研究和开发具有良好工艺性、耐热性和力学性能的低成本ＲＴＭ用树脂体系。研究表明，乙烯基酯树脂和环氧树脂体系具有良好的共混特性。ＤＳＣ及粘度分析研究表明，混合型树脂体系中的乙烯基酯组份分散了环氧树脂的反应放热，有效降低了７１１环氧树脂的反应速度和改善了树脂的工艺特性。使混合型树脂具有较好的ＲＴＭ工艺低粘度平台工艺性能。所研究的混合型树脂体系可用于ＲＴＭ     

如何正确使用和维护RTM树脂注射机

树脂传递模塑工艺技术（ＲｅｓｉｎＴｒａｎｆｅｒＭｏｕｌｄｉｎｇ,简称ＲＴＭ工艺）是８０年代末国际复合材料工业迅速发展起来的高技术成型工艺。我国已有不少厂家从国外引进了ＲＴＭ注射系统,随着ＲＴＭ工艺技术的广泛推广及蓬勃发展,现在国内已有相当数量的ＲＴＭ...     

有机胺对RTM注射用树脂性能的影响

本文通过凝胶实验，化学分析，红外光谱、ＤＳＣ、力学性能测试等方法，研究了有机胺（Ｎ，Ｎ－二甲基苯胺，Ｎ，Ｎ－二乙基苯胺）对以ＭＥＫＰ／Ｃｏｎａｐ为固化体系的ＲＴＭ注射用不饱和聚酯树脂的凝胶和固化机理。在有机胺的作用下能有效地加速树脂的凝胶和固化。     

非均相孔隙纤维介质的RTM工艺探讨

分析了现有树脂的流动模型、工艺过程中气泡的形成和排出以及现有模型用于非均相孔隙纤维介质体系的差距，并讨论了材料性能、压力控制以及真空辅助手段对ＲＴＭ工艺、制件性能的影响。     

用于RTM的高性能树脂基体

本文简要介绍了ＲＴＭ的成型原理，并对ＲＴＭ用高性能树脂基体做了全面评述。     

RTM树脂的加热方法

ＲＴＭ树脂的加热方法ＲＴＭ工艺属于闹模模塑工艺，该工艺对树脂的加热方法有两大类：一是直接加热法。如美国ＲＰ／ＣＭａｃｈｉｎｅｒｙＣｏｒｐ．将射频电能直接通到型腔内的树脂中使树脂固化，该方法较先进，热效率最高，但难度大，目前只处于研究试验阶段；二是间接...     

RTM成型用CDR—9418的工艺性研究

本文介绍了ＲＴＭ成型用低粘度双马来酰亚胺基体树脂ＣＤＲ－９４１８的合成，及该树脂的成型加工工艺。     

RTM工艺的预成型技术研究

本文对ＲＴＭ成型工艺中定型粘合剂的选择作了详细研究，结果表明：丙烯酸型粘合剂用量为纤维用量的３％时，与不同的基体树脂有较好的相容性，从而使ＲＴＭ预成型工艺取得满意效果。     

High temperature vacuum assisted resin transfer molding of phenylethynyl terminated imide composites

Vacuum Assisted Resin Transfer Molding (VARTM) has proven to be a cost effective process for manufacturing composite structures compared with prepreg/autoclave and traditional resin transfer molding (RTM) processes. However, VARTM has not been accomplished with high temperature resins (such as polyimides) until recently, primarily because no resins had low melt viscosity and long melt stability that are required by VARTM. With the recent invention of phenylethynyl terminated imides (PETIs), high temperature VARTM has been achieved. Two processing methods, in‐plane and through‐thickness resin flow, were proposed and tested. Both methods are capable of fabricating polyimide matrix composites; and the carbon fiber laminates yield good fiber‐resin interfacial bonding and comparable mechanical properties to those laminates fabricated using RTM. POLYM. COMPOS., 2011. © 2010 Society of Plastics Engineers     

Properties of poly(butylene terephthatlate) polymerized from cyclic oligomers and its composites

The high viscosity of thermoplastic matrices hampers fiber impregnation. This problem can be overcome by using low viscous polymeric precursors such as cyclic butylene terephthalate (CBT^® resins), which polymerize to form a thermoplastic matrix. This allows thermoset production techniques, like resin transfer molding (RTM), to be used for the production of textile reinforced thermoplastics. Due to the processing route and more specifically the time-temperature profile, inherent to the RTM process, the crystallites of the matrix consist out of well-defined, thick and well-oriented crystal lamellae. Together with a high overall degree of crystallinity and a low density of tie molecules, these large and perfect crystals cause polymer brittleness. Matrix brittleness lowers the transverse strength of unidirectional composites to below the matrix strength, but leaves the mechanical properties in the fiber direction unaffected. Although not a valid option for the RTM production route, crystallization from a truly random melt and at a sufficiently high cooling rate would substantially improve the ductility.     

酚醛树脂及其复合材料成型工艺的研究进展

随着社会的发展,人们越来越重视安全和环保。新型酚醛树脂品种和酚醛树脂新的成型工艺得到了发展。文中介绍了酚醛树脂的改性方法。重点介绍了基于酚醛树脂的RTM、拉挤等复合材料成型工艺研究进展。     

一种高温环氧树脂的工艺及力学性能

对比研究了国产MERICAN 3768和国外CYCOM 890 RTM两种高温环氧树脂的工艺性和力学性能。同时选取典型航空结构,采用双轴向碳纤维织物和真空灌注工艺制备了对比零件。结果表明,国产MERICAN 3768树脂的浸润性、流变固化特性和力学性能均与国外CYCOM 890 RTM树脂相当,均具有优异的工艺性和力学性能,与纤维匹配性好,满足航空应用对树脂的要求。     

RTM用基体树脂研究进展

介绍RTM用环氧树脂、不饱和聚酯、聚酰亚胺、酚醛树脂及其他树脂的研究进展.     

复合材料RTM模具的制备

根据树脂传递模塑(RTM)模具对基体树脂的基本要求,选用双酚A环氧乙烯基酯树脂为基体,聚乙酸乙烯酯为低收缩添加剂,玻璃纤维经编织物为增强材料,并加入相应的助剂,制备了复合材料RTM模具。该模具具有成本较低、开发周期短、精度较高等优点,但表面强度和热效率较低。     

Bismaleimide Systems for High-Performance Radomes

Three modified bismaleimide resin systems (designated as systems I, II, and III) for high-performance radomes are introduced. Their glass transition temperatures are 274°, 268°, and 265°C, respectively; and their dielectric loss tangents at 10 GHz are 0.0117, 0.0108, and 0.0118, respectively. System I and system II are suitable for hot-pressing process; and system III, which has attractive processing characteristics, is suitable for resin transfer molding (RTM). The injection temperature of system III is room temperature, at which its viscosity is only 0.38 Pa·sec. In addition, its working life is more than 40 h. Properties of neat resins and composites are investigated; all data show that they have good thermal and mechanical properties as well as excellent dielectric properties. These indicate that the three modified bismaleimide resins can be used as matrix resins for advanced radomes.     

Processing of highly elastomeric toughened cyanate esters through a modified resin transfer molding technique

Model cyanate ester resins containing different quantities of epoxy functional butadiene-acrylonitrile rubber (ETBN) to improve the fracture performance were developed as matrices for composites. With the elastomeric modification, the resin systems exhibited rheological characteristics inappropriate for laminate fabrication by conventional resin transfer molding (RTM). To fabricate the carbon fiber based laminates in one liquid molding operation successfully, a process named bleed resin transfer molding (BRTM) was established. The BRTM process combines features of RTM and resin film infusion processes (RFI) and was therefore appropriate for processing high viscosity matrix resins. A novel catalyst was selected for the cyanate ester resin that provided enough latency for the impregnation steps in the BRTM process. Through the use of thermal analytical tools, a high degree of phase separation and conversion was obtained. The conversion and the glass transition temperature were found not to decrease with increasing elastomer content, which is in contradiction to most toughening modifications. Mode I and Mode II interlaminar fracture toughness were found to increase significantly with increasing elastomer content. In Mode I, an increase of up to 140% was observed. Collectively, this work showed that through the use of the BRTM technique, matrices with toughness improvements usually only achieved by prepreg systems can be processed in an RTM-like manner.     

Processing and properties of resol and epoxy blends for resin transfer molding

Blends of epoxy and resol matrices for resin transfer molding (RTM) have been prepared and characterized with the double aim of improving the processability of resols and the fire resistance of epoxies. The reaction rate of the overall system is enhanced by the exothermic reaction between the epoxy and an aliphatic amine, which also promotes the resol reaction. In addition, the mechanical behavior of the resol is improved as the shear stress increases with the addition of epoxy resins. However, blending also produces a reduction of the intrinsic fire resistance of phenolic resins. The study demonstrated the feasibility of producing blends for matrices of composites processed by resin transfer molding. The recommended range for the epoxy content was determined through a balance of processability, fire resistance, and mechanical properties of the composites obtained. Moreover, the effects of fiber surface modifications were studied as a way to promote higher shear stresses in the epoxy-resol matrix composite without jeopardizing the fire resistance properties.     

Flow and cure phenomena in liquid composite molding

Liquid molding processes including resin transfer molding (RTM) and structural reaction injection molding (SRIM) continue to attract attention due to their potential for high volume manufacture. This paper examines and compares the pressuare and temperature histories observed in mold cavities during impregnation, heating, and polymerization for both RTM and SRIM using polyester, vinyl ester, and polyurethane resins in combination with continuous strand mats. Experimental results are related to thermal, chemical and rheological effects. Factors which influence materials behavior and process control and the implications for mold design are discussed.