长玻璃纤维增强聚丙烯

采用自行研制的熔体浸渍包覆长玻璃纤维装置,制备了长玻纤增强聚丙烯(LFT-PP)复合材料。研究了玻纤含量(10%(质量分数,下同)、20%、30%、和40%)、预浸料粒料长度(3mm和18mm)及相容剂聚丙烯接枝马来酸酐(PP-g-MAH)含量(2%、4%、6%、和8%)对长玻纤增强聚丙烯(LFT-PP)复合材料力学性能的影响。结果表明,长玻璃纤维增强聚丙烯(LFT-PP)的力学性能明显优于短玻璃纤维增强聚丙烯,当玻纤含量在30%时,拉伸强度达到50MP左右,冲击强度达到6kJ/m2左右,相容剂PP-g-MAH的加入增强了界面粘接强度,大幅度地提高了长玻纤增强聚丙烯(LFT-PP)复合材料的力学性能,当相容剂PP-g-MAH含量达到3%左右,其综合力学性能达到最佳值,拉伸强度达到100MP左右,冲击强度达到10kJ/m2左右。     

混杂比对单向碳-玻层间混编复合材料0°压缩和弯曲性能的影响

本文研究了相同铺层方式下不同混杂比对单向碳-玻(碳纤维-玻璃纤维)层间混编复合材料的0°压缩和弯曲性能的影响。以碳-玻层间混编形式向纯玻纤织物中混入碳纤维,对复合材料的0°压缩强度、0°压缩模量、弯曲强度和弯曲模量均有一定的提高作用,三种碳纤混杂比不同的复合材料0°压缩强度较纯玻纤结构分别提高了22.72%、26.95%、11.43%,混杂比不同所导致的试样破坏程度也各不相同。混杂复合材料0°压缩模量随碳纤含量增加逐渐增大。三种碳纤混杂比复合材料弯曲强度基本一致,而弯曲弹性模量随碳纤含量增加逐渐增大。     

电子接插件用聚苯硫醚高性能复合材料的研制

聚苯硫醚（PPS）具有耐高温、耐腐蚀、高强度、高绝缘、阻燃等特点,将其与纤维进行复合,可获得更高的强度和高温稳定性,是目前用于接插件最理想的高性能工程塑料,但制件的薄壁连接处易开裂是困扰接插件制造者的难题。通过研究三种增韧体系对聚苯硫醚复合材料的增韧效果,获得了一种增韧增强的高性能聚苯硫醚复合材料,可成功解决接插件制件易开裂的问题,该材料性能优于国外同类产品,满足军用接插件制造者的要求。优选的增韧体系对于不同厂家的国产PPS原树脂都具有明显的增韧增强效果。     

短切玻璃纤维增强硬质聚氨酯的弹性模量

采用一步法制备玻纤增强硬质聚氨酯的复合材料(RPU).不同长径比的玻纤增强RPU的性能差异显著.长径比为40的玻纤表现出最优的增强性能.当玻纤用量为10%时,长径比为20、40和100的玻纤增强材料的弹性模量分别为9.39MPa、10.5 MPa和9.59MPa,其中长径比为40的玻纤增强材料的弹性模量比未增强的增加了55%,而长径比为20和100的玻纤增强分别为38.7%和41.7%;该材料增强的压缩弹性模量与拉伸弹性模量规律几乎一致.SEM图表明适宜长径比的纤维本身的拉伸强度对增强硬泡塑料的力学性能起到了重要作用.     

玻纤增强注塑件的均匀化弹性力学参数研究

基于均匀化方法,根据长玻纤增强聚丙烯(LGFR-PP)的微观特征,建立了非连续长玻纤增强复合材料的代表性体积单元(RVE),通过有限元方法模拟预测了复合材料的宏观等效弹性力学参数,与注塑样条拉伸性能测试结果进行了比较。研究表明,通过在玻纤两侧增加聚丙烯(PP)分布,所采用的RVE较传统连续纤维的有限元模型更为合理;当玻纤成单一取向时,玻纤增强聚丙烯为一种横观各向同性材料;改变玻纤取向与拉伸方向之间的角度,拉伸方向的等效模量先微幅减小,再迅速降低,而后趋于稳定。利用均匀化方法预测非连续长玻纤增强注塑件的等效弹性力学性能具有较高的工程可行性,能进一步为玻纤增强注塑件的结构服役性能分析提供科学依据。     

长纤维增强PBT

Ticona公司德国Celanese分公司可提供新品级的系列长玻纤增强PBT产品 ,其牌号为CelstranPBT -GF30 (玻纤30wt%,下同 ) ,PBT -GF40和PBT -GF5 0。同时Ticona公司还推出以 40wt%的长碳纤维增强的PBT ,其牌号为CelstranPBT -CF40。Ticona公司称新产品所使用的PBT采用特殊的配方以使之适于用长纤维增强。该公司产品市场部经理介绍 ,长纤维增强PBT的新产品性能与增强PP相近 ,但力学性能更好 ,且比长玻纤增强尼龙硬度高 ,而韧性几乎相同。同PP相比 ,新的CelstranPBT品级产品更易于着色和涂覆涂料。与尼龙相比 ,该产品不具吸湿…     

玻纤质量分数对长玻纤增强聚丙烯水驱动弹头辅助注塑管件的影响

分别以玻纤质量分数10%,20%,30%和40%的长玻纤增强聚丙烯（LGFRPP）材料制取一系列水驱动弹头辅助注塑（W-PAIM）管件。探究了玻纤质量分数对玻纤断裂长度、纤维取向、壁厚以及耐压性的影响。结果表明,随着玻纤质量分数的增加,玻纤断裂长度在较长区间内占比降低;不同玻纤质量分数的W-PAIM制件在壁厚层的取向不同,水道层的玻纤沿流动方向取向较模壁层和中间层更好,当玻纤质量分数为10%与40%时,水道层玻纤取向度最好,玻纤质量分数为20%时,中间层取向最差,玻纤质量分数为30%时,模壁层的玻纤取向较好;随着玻纤质量分数的增加,WPAIM管件壁厚呈先增加后减小再增加的趋势;随着玻纤质量分数的增加,管件的耐压性先增加后减小最后又增加,当玻纤质量分数为20%时,耐压性最好。     

碳纳米纤维纸-玻纤/环氧复合材料对风力发电叶片的影响

针对风力发电叶片在多风沙环境下的固体粒子冲蚀磨损行为, 研究了风力发电叶片专用环氧树脂(EPIKOTE^TM RIM 135、EPIKURE^TM RIM H 137)、传统玻纤增强环氧复合材料和新型碳纳米纤维纸-玻纤/环氧复合材料的固体粒子冲蚀磨损行为, 并测试了不同材料的玻璃化转变温度, 进而对比分析了其对冲蚀磨损的影响; 针对风力发电叶片在寒冷环境下表面容易结冰的现象, 研究了上述三种材料表面的疏水性能, 并测试了它们对水的接触角大小。结果表明: 碳纳米纤维纸-玻纤/环氧复合材料具有良好的界面结合, 且碳纳米纤维纸的引入提高了碳纳米纤维纸-玻纤/环氧复合材料的玻璃化转变温度(从55 ℃提高到63 ℃), 从而改善了其耐固体粒子冲蚀磨损性能; 同时, 碳纳米纤维纸的加入改善了碳纳米纤维纸-玻纤/环氧复合材料的表面疏水性能(接触角从104°提高到131°)。     

玻璃纤维增强乙烯基酯树脂复合材料的增韧

聚合物基复合材料的增韧一直是高分子材料领域研究的热点之一．文中从乙烯基酯树脂基体增韧、乙烯基酯树脂／玻璃纤堆界面改性及增强材料结构和形式的优化三个方面对玻璃纤堆增强乙蜂基酯树脂复合材料的增韧进行了综述,介绍了各种增韧方法的机理和增韧效果,对这些增韧方法进行了评述．并分析了今后的发展方向．     

无卤氮磷膨胀阻燃玻纤增强聚丙烯复合材料的制备与性能

因玻纤"烛芯效应"制备阻燃玻纤增强聚合物复合材料是具有挑战性的课题。文中以自制的膨胀型阻燃剂MPAL与八乙烯基倍半硅氧烷(OV-POSS)组成的复合阻燃剂阻燃玻纤增强聚丙烯(PP),研究了玻纤(GF)和增容剂马来酸酐接枝聚丙烯(MAPP)对阻燃PP体系的阻燃性能和力学性能的影响,结合扫描电镜和热重分析探讨了相应阻燃机理。结果表明,在阻燃PP体系中加入玻纤及适当增加其含量会显著改善阻燃PP材料的阻燃性能,归因于加入玻纤提高了阻燃PP体系的热稳定性以及利用MPAL/OV-POSS分解形成的复合炭层覆盖于玻纤表面,从而达到阻断玻纤"烛芯效应"目的。此外,加入增容剂MAPP及适当增加其含量会明显提高阻燃玻纤增强PP复合材料的力学性能,但对材料阻燃性能改善有限,归因于MAPP对体系界面结合和相容性的显著改善作用。当玻纤和MAPP质量分数分别为30%和5%时,所得阻燃玻纤增强PP复合材料具有优异的综合性能,表现出良好的应用前景。     

Biomicrofibrilar composites of high density polyethylene reinforced with curauá fibers: Mechanical,interfacial and morphological properties

Vegetal fibers are used in polymer composites to improve mechanical properties, substituting inorganic reinforcing agents produced by non renewable resources, like fiberglass. The highest performance formulation in high density polyethylene, HDPE, composites reinforced with curauá fibers were studied, aiming to improve the interphase interaction and optimize the mechanical properties. The fiber content, the type and the concentration of coupling agent were tested. The composites and the pure materials were characterized by Fourier transform infrared spectroscopy and the fiber/matrix phase adhesion was evaluated by scanning electron microscopy. The mechanical properties and the micrographs showed that the best formulation is: 20 wt.% of milled curauá fibers and 2 wt.% poly(ethylene-g-maleic anhydride). The coupled composites are also less hygroscopic than the uncoupled composites. We conclude that the composites reinforced with curauá fibers have mechanical properties comparable to commercially produced composites of HDPE reinforced with fiberglass.     

Nondestructive Evaluation of Fiberglass Wrapped Concrete Bridge Columns

Many in-service concrete bridge decks and columns built before the advent of epoxy coated bars show cracking and spalling of the concrete due to corrosion of the steel reinforcement. In cold regions, the corrosion rate of concrete bridge decks and columns is accelerated by the use of deicing solutions in winter. The corrosion of the steel rebars causes cracking, delamination, and spalling of reinforced concrete structures and increases the cost of rehabilitation and maintenance operations. In Wisconsin (USA), fiberglass wrapping has been used for corrosion protection of reinforced concrete columns. In this methodology, a fiberglass wrap is placed as a barrier between the concrete surface and the surrounding environment and is expected to reduce the detrimental effect of traffic splashing of deicing solutions. This paper describes a study aimed at evaluating the effectiveness of fiberglass wrapping in controlling and reducing the rate of corrosion in bridge concrete columns. Field tests included nondestructive wave propagation and half-cell potential methods. Nondestructive evaluation results were examined and compared to chloride ion (Cl⁻) intrusion measurements. The data show that fiberglass wrapping helps in arresting the chloride ion ingress to the columns, however, it does not help reduce corrosion rates in chloride contaminated concrete columns.     

An automated technique for manufacturing thermoplastic stringers in continuous length

In the present work an automated Continuous Compression Moulding Technique for the manufacture of stringers in continuous length is presented. The method combines pultrusion and hot-pressing. The technique is utilized for the production of L-shape stringers which are widely applied in aerospace constructions. The investigation was carried out on carbon reinforced PEEK (C/PEEK), as well as, for comparison, on the thermoplastic composites carbon reinforced polyethersulfon (C/PES), glass and carbon reinforced polyphenylene-sulfide (G/PPS, C/PPS) and Kevlar reinforced Polyamide 6 (K/PA 6).

For the materials investigated the optimized process parameters for manufacturing the L-shape stringers were derived experimentally. To achieve this goal, the quality of the produced parts was controlled by using non-destructive testing techniques. Parts providing satisfactory quality were also tested destructively to measure their mechanical properties. The investigation results have shown the suitability of the technique to produce continuous length stringers.     

Effect of fiber-matrix adhesion on the creep behavior of CF/PPS composites: temperature and physical aging characterization

The influence of fiber-matrix adhesion on the linear viscoelastic creep behavior of ‘as received’ and ‘surface modified’ carbon fibers (AR-CF and SM-CF, respectively) reinforced polyphenylene sulfide (PPS) composite materials was investigated. Short-term tensile creep tests were performed on ±45° specimens under six different isothermal conditions, 40, 50, 60, 65, 70 and 75 °C. Physical aging effects were evaluated on both systems using the short-term test method established by Struik. The results showed that the shapes of the curves were affected neither by physical aging nor by the test temperature, allowing then superposition to be made. A unified model was proposed with a single physical aging and temperature-dependent shift factor, \(a_{T,te}\). It was suggested that the surface treatment carried out in SM-CF/PPS had two major effects on the creep response of CF/PPS composites at a reference temperature of 40 °C: a lowering of the initial compliance of about 25 % and a slowing down of the creep response of about 1.1 decade.     

玻璃纤维增强复合材料抗爆容器的研究进展

综述了国内外树脂基玻璃纤维增强复合材料抗爆容器的主要研究成果,对纤维材料及粘合剂的选取、纤维缠绕方式、壳体的动态响应及失稳抑制、容器的抗爆能力和尺度效应等方面进行了较全面的总结.简要介绍了其在航空航天、工业及国防等领域的应用情况.     

聚苯硫醚及其玻璃纤维增强复合材料力学性能研究

本文利用差示扫描量热仪(DSC)研究了国产低分子量聚苯硫醚及其固相热处理产物的热行为,并用悬浮-熔融法制备了玻璃纤维增强聚苯硫醚复合材料的预浸带,测定了其单向板的力学性能,观察了其断口形貌。结果表明:低分子量聚苯硫醚经过固相热处理后,其T_g、T_c上升,T_m下降;热处理后的聚苯硫醚玻纤复合材料在室温时的力学性能有很大程度的提高,其高温性能受玻璃化转变的影响显著;通过SEM观察断口发现其破坏主要属于界面脱粘。     

Influence of annealing duration on the erosive wear behavior of polyphenylenesulphide composites

The influence of annealing duration on the erosive wear behavior of short glass fiber (40% w/w) and CaCO₃ mineral particulate (25% w/w)–short glass fiber (40% w/w) (total: 65% w/w) reinforced PPS composites has been characterized under various experimental conditions by differential scanning calorimetry (DSC) and erosion measurements. The erosive wear of the composites have been evaluated at different impingement angles (30, 45, 60, and 90°) and at four different annealing periods (30, 60, 90, and 120 min). Increase in the total crystallization causes an improvement in the erosive wear properties of the samples. Annealing time controls the morphology by influencing the degree of crystallinity in the matrix and in the fiber–matrix interface. This formation restricts fiber–matrix debonding. There is no linear proportionality between annealing time and relative degree of crystallization. The results indicate that PPS composites show maximum in wear versus impact angle relation at 60° confirming their semi-ductile failure behavior. The morphologies of eroded surface are examined by the scanning electron microscope.     

应变率效应对短纤维增强热塑性树脂PPS力学性能的影响

本文通过大量的实验,研究了应变率效应对短纤维增强热塑性树脂PPS(聚苯硫醚)力学性能的影响,应变率变化范围从10-4/s～102/s.并对断口形貌及破坏形式进行了观察.研究结果表明:应变率较高时对材料的强度和模量有明显影响,而且应变率不同断口形貌也存在一定的差别.断口形貌呈脆性破坏.     

PPS/PES共混物及其碳纤维复合材料内耗行为的研究

本工作利用内耗测量方法研究了PPS/PES共混物及其碳纤维复合材料的相容性以及多重转变和松弛行为,结果表明:(1)PPS与PES存在分子运动水平上的相互作用,共混组份比是决定其相互作用程度的重要因素;(2)PPS/PES共混物及其碳纤维复合材料中的PES相的β转变与松弛的时间存在较宽的连续分布,其分布宽度随共混组份比变化而变化,当PES相对含量为80%时,松弛时间分布宽度出现最大值;(3)PPS/PES共混物及其碳纤维复合材料处于热力学亚稳态,热处理增大了PPS与PES的相分离程度,减弱了它们之间的相互作用;(4)低温区热历史对PPS玻璃化转变有较大影响,内耗峰高及峰温随起始测量温度的升高而下降。