191#不饱和聚酯／玻璃钢人工加速老化研究

对191#不饱和聚酯及其玻璃钢进行了人工热氧加速老化和人工氙灯加速老化试验.用显微镜观察了试样的外观形貌,用光泽度仪测试了试样光泽度,色差计测定了试样表面的黄色指数,对聚酯进行了FT-IR和DMA分析,测试了聚酯和玻璃钢的拉伸强度和弯曲强度.试验表明,随着加速老化时间的延长,试样表面出现光泽度降低、泛黄、龟裂等现象,且失光率、泛黄程度、裂纹长度和力学性能的变化与人工老化方式相关,DMA分析证实聚酯氙灯老化90天后Tg由84℃上升到88℃,老化240天后为83℃,聚酯老化后的储存模量也有一定程度的下降;而弯曲强度、拉伸强度则出现先上升后下降趋势;191#聚酯/玻璃钢对氙灯老化更为敏感.     

不饱和聚酯玻璃钢与环氧乙烯基酯玻璃钢耐久性能试验研究

采用湿热老化、冻融循环及紫外老化等加速试验方法,通过质量变化率、弯曲强度保留率及SEM分析,对189不饱和聚酯玻璃钢及MFE-2环氧乙烯基酯玻璃钢在海洋环境中的腐蚀机理和耐久性进行了详细研究。试验结果表明,湿热老化150d后,189不饱和聚酯玻璃钢及MFE-2环氧乙烯基酯玻璃钢的质量变化率分别为-6.03%和0.31%,弯曲强度保留率分别为26.2%和47%;紫外老化300h后,弯曲强度保留率分别为84%和94%;1000次冻融循环后,弯曲强度保留率分别为30%和65%。基体树脂分子链上酯基的密度是影响玻璃钢在海洋环境中耐久性的关键因素,MFE-2环氧乙烯基酯树脂分子链上酯基的密度约为189不饱和聚酯树脂分子链上酯基密的1/3,所以MFE-2环氧乙烯基酯玻璃钢在海洋环境中具有更好的耐久性。     

不饱和聚酯玻璃钢人工加速老化研究

介绍对添加与不加紫外线吸收剂的不饱和聚酯玻璃钢进行3000h湿热加速老化和人工气候加速老化的试验结果。讨论了添加紫外线吸收剂、环境条件、加工工艺等对老化试验样品外观、弯曲强度和冲击强度的影响。并介绍了有关防止老化的措施。     

191～#不饱和聚酯树脂西部曝晒和人工加速老化的研究

对191#不饱和聚酯树脂进行了自然曝晒老化、人工热氧加速老化及人工氙灯加速老化试验,并对老化前后试样的外观形貌、光泽度、黄色指数、拉伸强度和弯曲强度进行了研究。实验结果表明,随着加速老化的不断进行,试样表面会出现泛黄、失光率增大和裂纹等现象,强度呈先增后降的趋势,弯曲强度由20 MPa(未老化时)增至最大值40 MPa(热氧老化60 d或氙灯老化45 d),拉伸强度由113 MPa(未老化时)增至最大值125 MPa(氙灯老化30 d)和128 MPa(热氧老化60 d);老化方式不同,老化前后试样的性能变化也不相同,即失光率对热氧老化更敏感、强度对紫外光老化更敏感;西部曝晒180 d,不饱和聚酯树脂仍处于后固化阶段,但强度已开始下降,下降程度与曝晒地区有关,变化最明显的是新疆尉犁地区,弯曲强度由最大值40 MPa(自然曝晒120 d)降低至35 MPa(自然曝晒180 d)。     

玻璃纤维增强复合材料的人工加速老化性能研究

对轨道结构用玻璃纤维增强复合材料（GFRP）进行了氙灯加速老化及湿热老化试验,研究了GFRP的弯曲强度、压缩强度等随老化时间的变化情况,并考查了不同化学介质对成品性能的影响。结果表明,该种GFRP具有优异的耐光老化、耐湿热老化及耐化学介质性能。     

基于生命周期模型的木塑复合材料研究分析

以加速老化为手段,考察氙灯照射和冻融循环对高密度聚乙烯(HDPE)/稻糠粉和HDPE/秸秆粉两种木塑复合材料弯曲强度的影响。结果显示,同等条件下,HDPE/秸秆粉木塑复合材料的弯曲强度显著大于HDPE/稻糠粉木塑复合材料。经过氙灯照射和冻融循环后,两种木塑复合材料的弯曲强度均下降,且它们的弯曲强度下降程度随着氙灯照射时间的增加而增加,随着冻融温差的增加而增加。无重复双因素方差分析结果显示,氙灯老化时间和冻融循环温度对两种木塑复合材料的弯曲强度影响均非常显著(p0.05,这里p表示显著性差异水平)。     

透明玻璃钢表面防老化技术研究

本文通过人工加速老化试验,对透明玻璃钢的透光率及强度测试,研究了聚三氟乙烯涂层、防老化薄膜及富树脂保护层对透明聚酯玻璃钢的老化性能的影响。     

玻璃钢在盐雾环境中腐蚀机制和性能演变规律的试验研究

本文在总结复合材料在海洋的盐雾环境中使用的材料腐蚀理论基础上,分析复合材料发生腐蚀的主要形式和历程,模拟自然环境试验设计不同盐雾温度、不同老化时间下的加速老化试验,通过材料表面形貌、玻璃化转变温度、微观结构的变化来评价玻璃钢在盐雾中的腐蚀性能,着重分析温度、时间对材料腐蚀性能的影响规律;根据中值老化寿命和剩余强度之间的关系式,建立了加速寿命规律模型和寿命预测模型;根据试验中玻璃钢力学性能随老化时间的衰减多数情况下具有一致的规律性,建立了盐雾环境中玻璃钢力学性能随老化时间的衰减三线型模型。试验结果表明,在盐雾环境中,玻璃钢除了可见的外观发生变化外,其玻璃化转变温度、表面巴氏硬度、拉伸强度和弯曲强度均呈现下降趋势,并且随温度的提高和腐蚀时间的延长,性能下降会进一步加大;中值老化寿命和剩余强度之间的关系式能比较好地描述聚合物基复合材料自然老化规律和加速老化规律,力学性能随老化时间的衰减三线型模型能够直观的反映玻璃钢在盐雾环境中加速老化的各个阶段。     

玻纤增强ABS氙灯老化性能的研究

通过双螺杆挤出机制备得到了玻纤增强ABS复合材料体系,对比研究了该复合材料体系氙灯老化性能.结果表明:氙灯老化试验1000h后,玻纤增强ABS复合材料体系拉伸强度和弯曲强度降低.相对于纵向的拉伸破坏,氙灯老化作用对玻纤增强ABS抵抗横向弯曲破坏的影响有限.老化后的玻纤增强ABS复合材料体系冲击韧性下降,但弯曲模量略有升...     

抗紫外老化高强聚酯纤维的制备与性能研究

针对制备抗紫外老化高强聚酯纤维对添加剂分散性和聚酯相对分子质量的要求,选用双苯并噁唑二苯乙烯(OB-1)作为紫外吸收剂,采用原位聚合和固相增黏法制备了抗紫外老化增黏聚酯,再通过低速纺丝、多倍拉伸的方法纺制了抗紫外老化高强聚酯纤维。结果表明:OB-1不影响聚酯的聚合和增黏过程,随着OB-1的加入,聚酯熔体非牛顿指数降低;添加OB-1质量分数0~0.05%,所得抗紫外老化增黏聚酯切片的特性黏数大于0.85 dL/g,抗紫外老化高强聚酯纤维断裂强度大于6.8 cN/dtex,达到了产业用高强聚酯纤维的要求;经过300 h人工氙灯加速老化,添加OB-1质量分数0.05%的聚酯纤维强度保持率达到96%,抗紫外老化效果好。     

不饱和聚酯片状模塑料力学性能的研究

研究了玻纤布、短切玻纤及碳酸钙对不饱和聚酯片状模塑料力学性能的影响,实验发现:玻纤布增强不饱和聚酯片状模塑料的力学性能比短切玻纤好,随着玻纤含量的增加,不饱和聚酯片状模塑料的拉伸强度先增加,达到一极大值之后减少。碳酸钙填充不饱和聚酯片状模塑料,随着碳酸钙含量的增加,不饱和聚酯片状模塑料的拉伸强度明显降低,弯曲强度增加。     

短切玻璃纤维毡增强不饱和聚酯树脂复合材料的性能研究

以不饱和聚酯为基体,以玻璃纤维毡为增强材料,加入促进剂、固化剂等添加剂,通过常温固化得到其板材,然后对其拉伸强度、冲击强度等性能进行测试,研究各种成分不同配比对材料力学性能的影响。结果表明以无碱玻璃纤维毡为增强材料,不饱和聚酯和玻璃纤维毡的质量比为3︰1,促进剂、固化剂的加入量为树脂量的0.5%、1%,制得的样品力学性能最好,拉伸强度达到80 MPa以上,冲击强度达到40 kJ/㎡以上。     

Coupling agent and glass fibers in polyester mortar

This study investigates the influence of aggregates, glass fibers and a coupling agent on the compressive and flexural (three-point and four-point bending) behavior of a polyester mortar. Particle size of fine aggregates (quartz and limestone) varied from 0.1 to 5 mm (0.004 to 0.2 inch) and the glass fiber content was varied up to 6% by weight of mortar. A silane was introduced into the polyester mortar by pretreating the aggregates and the glass fibers. The mechanical properties of mortar were studied at room temperature. The test results indicate that the selection of aggregate type, size and distribution is very important. Silane treated aggregate systems showed more than 66% increase in compressive strength and 35% increase in flexural strength when compared to the untreated systems. Addition of glass fibers enhances the strength and toughness of the polyester mortar, and silane treatment of glass fibers helps to further enhance these properties. Flexural (three-point bending)-to-compressive strength ratio varied from 0.28 to 0.35 for unreinforced system and from 0.26 to 0.54 for the reinforced system. The mortar with only 14% polyester and 86% aggregates (by weight) and a coupling agent had a compressive strength of 103 MPa (15,000 psi) which is 94% of the polyester polymer strength. A stress-strain relationship is proposed to represent the complete stress-strain response under compression and flexural loading. Also, a method is proposed to quantify the failure patterns.     

Experimental characterization of traditional composites manufactured by vacuum‐assisted resin‐transfer molding

The primary purpose of this study is to investigate the anisotropic behavior of different glass‐fabric‐reinforced polyester composites. Two commonly used types of traditional glass fabrics, woven roving fabric and chopped strand mat, have been used. Composite laminates have been manufactured by the vacuum infusion of polyester resin into the fabrics. The effects of geometric variables on the composite structural integrity and strength are illustrated. Hence, tensile and three‐point‐bending flexural tests have been conducted at different off‐axial angles (0, 45, and 90°) with respect to the longitudinal direction. In this study, an important practical problem with fibrous composites, the interlaminar shear strength as measured in short‐beam shear tests, is discussed. The most significant result deduced from this investigation is the strong correlation between the changes in the interlaminar shear strength values and fiber orientation angle in the case of woven fabric laminates. Extensive photographs of fractured tensile specimens resulting from a variety of uniaxial loading conditions are presented. Another aim of this work is to investigate the interaction between the glass fiber and polyester matrix. The experiments, in conjunction with scanning electron photomicrographs of fractured surfaces of composites, are interpreted in an attempt to explain the interaction between the glass fiber and polyester. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Polyester composites reinforced with noncrimp stitched glass fabrics: Experimental characterization of composites and investigation on the interaction between glass fiber and polyester matrix

The primary purpose of the study was to investigate the anisotropic behavior of different noncrimp stitched fabric reinforced polyester composites. The effects of geometric variables on composite structural integrity and strength are illustrated. Hence, tensile, three‐point bending flexural and short beam shear tests were conducted up to failure on specimens strengthened with different layouts of fibrous plies in noncrimp stitched fabric. The remark, based on the observations while tensile testing, is that the stress–strain curves of polyester based composites were linear in the direction of fibers. However, in the matrix dominated orientations nonlinear relation between the stress and the strain was observed. Another aim of the present work was to investigate the interaction between glass fiber and polyester matrix. The experiments, in conjunction with scanning electron photomicrographs of fractured surfaces of composites, were interpreted in an attempt to explain the interaction between glass fiber and polyester and were interpreted in an attempt to explain the instability of polyester resin–glass fiber interfaces. It was concluded that the polymer was either deposited between adjacent fibers or as widely separated islands on the fiber surface. Infrared spectra of the cured polyester and its glass fiber composite were obtained by Fourier transform infrared spectroscopy. POLYM. COMPOS., 2008. © 2007 Society of Plastics Engineers     

玻纤增强ABS复合材料的制备及性能

以丙烯腈-丁二烯-苯乙烯共聚物(ABS)及玻璃纤维(GF)为原料,以环氧树脂作为界面相容剂,研究了界面相容剂对玻璃纤维增强ABS复合材料力学性能及界面粘接的影响.结果表明:加入环氧树脂,玻纤增强ABS复合材料的力学性能明显提高;随着玻纤质量分数的增加,复合材料的拉伸强度、弯曲强度、冲击强度均逐渐增加;玻纤质量分数为30%时,GF/ABS/环氧树脂复合材料的拉伸强度比未改性的复合材料的拉伸强度提高了30%,弯曲强度提高了25%,冲击强度也提高了50%.     

玻纤增强PP热塑性片材的制备及力学性能研究

采用熔融浸渍法制备了玻璃纤维毡增强聚丙烯（PP）热塑性复合片材；通过在PP中加入复合改性PP改善了基体与增强纤维间的相容性；考察了相容剂、PP种类及玻纤毡种类对复合片材的影响。结果表明，相容剂的加入可使复合片材的拉伸强度提高29％、拉伸模量提高23％、弯曲强度提高42％、弯曲模量提高25％；高熔体质量流动速率PP可使片材的弯曲与冲击性能进一步改善。连续玻纤毡和长玻纤毡增强PP复合片材，前者综合力学性能良好，而后者则冲击强度较弱、弯曲性能加强。     

玻璃纤维增强聚酰胺老化机理的研究

以30％玻纤增强的聚酰胺66（PA66）为对象，用紫外加速仪研究了辐照时间对玻纤增强PA66的吸湿率、力学性能和形貌的影响进行研究，探讨了玻纤增强PA66的老化机理。实验结果表明：玻纤增强聚酰胺经紫外老化后的吸湿率显著低于未增强聚酰胺；玻纤增强聚酰胺的拉伸强度、弯曲强度显著提高，紫外老化后力学性能保持率较高；玻纤增强聚酰胺抗老化的机理可能是玻璃纤维阻止了聚酰胺老化裂纹的进一步扩展，同时减缓了外界因素对聚酰胺本体的进一步侵蚀，老化速度减慢。     

玻纤增强玻璃复合材料抗弯和抗热震性能研究

采用"三明治"结构法将玻纤与硼硅酸盐玻璃基体复合成为玻纤增强玻璃复合材料,并对其抗弯性能以及抗热震性能进行了测试和分析。结果表明:在纤维体积分数为50%时,复合材料的抗弯强度较高,韧性更好;玻纤增强玻璃复合材料的抗热震性能相较于玻璃有显著地提高。     

RTM制备玻璃纤维增强环氧树脂复合材料的力学性能分析

以环氧树脂为基体,短切玻璃纤维和玻璃纤维布为增强材料,通过RTM工艺制备了玻璃纤维增强环氧树脂(GF/EP)复合材料,并研究了RTM工艺制备玻璃纤维布增强环氧树脂(L-GF/EP)和短切玻璃纤维增强环氧树脂(S-GF/EP)复合材料的拉伸和弯曲性能,分析了开孔对两种复合材料拉伸性能的影响。结果表明:在拉伸过程中,开孔试样因孔边产生的应力集中,导致其拉伸强度与无孔试样相比下降了30%左右;玻纤铺层类型的不同对复合材料的力学性能具有显著影响;L-GF/EP复合材料内部结构完整,在载荷作用下,复合材料的弯曲断裂呈现一定的假塑性断裂模式,达到弯曲极限挠度值后,出现一定程度的回弹现象,其力学性能优于S-GF/EP复合材料。