Mechanical Properties of Glass Fiber/Unsaturated Polyester Resin Composite Water Collector

The water collector is operated in the humid and hot environment of the cooling tower all the year round.It also needs to carry part of the weight of water and silt.Therefore,it is particularly critical to optimize the material of the water collector and improve its mechanical properties.Polyester,a general term of polymer obtained from polyols and polyacids,is a kind of engineering plastics with excellent properties and wide applications.Glass fiber is a reinforced plastic reinforcement material,and the biggest characteristic of it is the high tensile strength and good heat resistance.In this paper,glass fiber reinforced polyester resin composite material is prepared,its tensile properties and bending properties are tested,and the performance of the imported material JK2020B is compared and analyzed.The results show that the elastic modulus along the fiber direction is relatively high,but the interlayer force in the direction of thickness and width is very small.This review provides a guidance for production process.

Preparation and Investigation of Mechanical and Physical Properties of Flax/Glass Fabric Reinforced Polymer Hybrid Composites

Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that is highly consumed in reinforced composites for its superior mechanical strength. As opposed to that, flax obtained from flax stalks can be used as an alternative reinforcing material with synthetic fibers to minimize manmade fiber consumption. Hence, this research work addresses a few flax/glass-reinforced hybrid composites by using a thermoset polyester matrix. Here, six categories of samples are made, like neat flax, neat glass, and flax/glass fabric reinforced hybrid composite, followed by different stacking layer sequences and hand layout techniques during processing. Afterwards, the mechanical behavior, thermal stability, morphological behavior, and water absorption of hybrid samples were investigated. Among the developed samples, neat glass (NG) composite exhibits superior mechanical properties, while neat flax (NF) shows the lowest result. It is apparent that the mechanical properties and thermal stability of hybrid samples are in between NF and NG because, by adding glass with flax fabric, the strength of hybrid samples is increased. Moreover, it is noticeable that, due to multiple stacking layers of flax and glass, hybrid 3 and hybrid 4 show better strength than consecutive single stacking layers in hybrid 1 and hybrid 2. Among all hybrid composites, the H4 shows comparatively better mechanical and thermal properties due to having the glass layers on the outermost surface. In summary, this research work demonstrated the feasibility of flax fabric with glass fabric as a reinforced hybrid composite that can be used in automobile inner bodies, household furnishing, and home interior decoration.

Preparation and Investigation of Mechanical and Physical Properties of Flax/Glass Fabric Reinforced Polymer Hybrid Composites

Synthetic reinforced composites affect the environment adversely and have become a global concern, causing increased natural composite demand for sustainability and cost effectiveness. Glass is a popular material that is highly consumed in reinforced composites for its superior mechanical strength. As opposed to that, flax obtained from flax stalks can be used as an alternative reinforcing material with synthetic fibers to minimize manmade fiber consumption. Hence, this research work addresses a few flax/glass-reinforced hybrid composites by using a thermoset polyester matrix. Here, six categories of samples are made, like neat flax, neat glass, and flax/glass fabric reinforced hybrid composite, followed by different stacking layer sequences and hand layout techniques during processing. Afterwards, the mechanical behavior, thermal stability, morphological behavior, and water absorption of hybrid samples were investigated. Among the developed samples, neat glass (NG) composite exhibits superior mechanical properties, while neat flax (NF) shows the lowest result. It is apparent that the mechanical properties and thermal stability of hybrid samples are in between NF and NG because, by adding glass with flax fabric, the strength of hybrid samples is increased. Moreover, it is noticeable that, due to multiple stacking layers of flax and glass, hybrid 3 and hybrid 4 show better strength than consecutive single stacking layers in hybrid 1 and hybrid 2. Among all hybrid composites, the H4 shows comparatively better mechanical and thermal properties due to having the glass layers on the outermost surface. In summary, this research work demonstrated the feasibility of flax fabric with glass fabric as a reinforced hybrid composite that can be used in automobile inner bodies, household furnishing, and home interior decoration.

Fabrication and Characterization of Glass Fiber with SiC Reinforced Polymer Composites

Glass Fiber Reinforced Polymeric (GFRP) Composites are most commonly used as bumpers for vehicles, electrical equipment panels, and medical devices enclosures. These materials are also widely used for structural applications in aerospace, automotive, and in providing alternatives to traditional metallic materials. The paper fabricated epoxy and polyester resin composites by using silicon carbide in various proportions along with GFRP. The hand lay-up technique was used to fabricate the laminates. To determine the properties of fabricated composites, the tensile, impact, and flexural tests were conducted. This method of fabrication was very simple and cost-effective. Their mechanical properties like yield strength, yield strain, Young’s modulus, flexural modulus, and impact energy were investigated. The mechanical properties of the GFRP composites were also compared with the fiber volume fraction. The fiber volume fraction plays a major role in the mechanical properties of GFRP composites. Young’s modulus and tensile strength of fabricated composites were modelled and compared with measured values. The results show that composites with epoxy resin demonstrate higher strength and modulus compared to composites with polyester resin.

Interface Enhancement of Glass Fiber/Unsaturated Polyester Resin Composites with Nano-Silica Treated Using Silane Coupling Agent

Nano-silica treated with different kinds of coupling agent （KH550, A-143, A-151） was used to modify the surface condition of glass fiber, and then, the modified glass fiber/unsaturated polyester resin （UPR） composites materials were prepared. Scanning electron microscopy （SEM）, dynamic mechanical analysis （DMA）, and impact test were used to characterize the composite materials＇ structure and properties. The morphology of composite materials shows that the adhesion between nano-silica and glass fiber is improved when silane coupling agent is added in. The DMA and impact test results show that silane coupling agent （especially KH550 and A-151） could effectively improve the composite＇s mechanical properties. When the dose of KH550 was 0.1% （m ： m）, the storage modulus and impact strength reached the maximum.

湿热环境对环氧树脂基复合材料拉伸性能的影响

采用加速吸湿法得到玻璃纤维/L285环氧树脂基复合材料吸湿特性曲线,通过对比分析湿热处理前后的化学结构、断口微观形貌以及力学性能,研究了湿热环境对玻璃化转变温度、损伤机理、抗拉强度以及弹性模量的影响,探究湿热老化机制,为通用航空飞机的安全运行提供理论和实验依据。结果表明,该复合材料吸湿初期符合Fick第二定律,后期吸湿曲线逐渐趋于平缓,湿度一定时,温度越高,吸湿率越大,达到吸湿饱和时间越长。水浴温度由25 ℃增加到85 ℃时,饱和吸湿率增加209%,相应吸湿饱和时间增加46.50%;湿热处理后复合材料的拉伸断裂失效形式发生改变,抗拉强度降低30.97%,弹性模量在6%范围内波动,加载初期应力—应变曲线呈线性关系,后期呈非线性变化趋势;相对25 ℃干态试样,85 ℃湿态试样的玻璃化转变温度下降24 ℃,相应的化学结构未发生变化,但纤维-基体界面发生了不可逆的物理变化。

交变载荷下绝缘拉杆用GFRP电树枝劣化特性

气体绝缘组合电器(gas insulated switchgear,GIS)现场调试或运行过程多次发生绝缘拉杆内部击穿问题,影响工程投运与设备可靠性,迫切需要探明故障机理。该文选取GIS断路器绝缘拉杆用玻璃纤维增强环氧树脂复合材料(glass fiber reinforced epoxy resin composite,GFRP)为研究对象,通过计算分、合闸下绝缘拉杆主应力分布特性,设置交变载荷下电树枝劣化实验条件,研究不同交变载荷对GFRP内电树枝生长特性影响规律。结果表明,相较于单一载荷,交变载荷条件下GFRP中电树枝生长速度加快,平均击穿时间降低,击穿概率增大。基于复合材料力学仿真发现交变载荷下GFRP内树脂-纤维界面处会出现较大的应力集中,局部应力损伤已达到失效的临界值。综上,交变载荷下绝缘拉杆纤维-树脂界面机械损伤与绝缘劣化交互演进是造成绝缘击穿的主要原因,也可作为试验考核与结构设计的改进依据。

复合增强型岩棉板的研发

以岩棉裸板为基材,配以专用的酚醛树脂(粘结剂)和无机玻纤毡,将表面处理后的带胶玻纤毡与岩棉板基体通过在线固化烘干工艺制备出复合增强型岩棉板。重点研究了复合增强型岩棉板的施工性能以及对岩棉板力学性能指标的影响。结果表明,复合增强型岩棉板在力学性能上得到显著提升,且板面的平整性、洁净性、耐磨性更为良好,更便于施工使用。

Studies on interacting Blends of Acrylated Epoxy resin based Poly(Ester-Amide)s and Vinyl EsterResin

Epoxy resin based Unsaturated poly(ester-amide) resins (UPEAs) can be prepared by many methods but here these were prepared by reported method [1]. These UPEAs were then treated with acrylotl chloride to afford acrylated UPEAs resin (i.e. AUPEAs). Interacting blends of equal proportional AUPEAs and vinyl ester epoxy (VE) resin were prepared. APEAs and AUPEAs were characterized by elemental analysis, molecular weight determined by vapour pressure osmometer and by IR spectral study and by thermogravimetry. The curing of interacting blends was monitored on differential scanning calorimeter (DSC). Based on DSC data in situ glass reinforced composites of the resultant blends have been prepared and characterized for mechanical, electrical and chemical properties. Unreinforced blends were characterized by thermogravimetry (TGA).

玻纤增强复合材料在厦门地区自然老化及寿命预测研究

目的 研究玻璃纤维增强不饱和聚酯树脂的自然老化机理,预估该复合材料在厦门地区的使用寿命。方法 研究玻璃纤维增强不饱和聚酯树脂在厦门近海地区大气暴露、海水飞溅、海水全浸等3种方式下,自然老化3 a的表面形貌变化和力学性能变化规律。通过扫描电子显微镜、红外光谱仪观察试样的微观结构,解释老化机理。运用线性回归方程对该复合材料的使用寿命进行预测。结果 获得了该复合材料的拉伸强度和弯曲强度等力学性能在老化过程中的变化规律,得到了大气暴露方式下试样的线性回归方程,计算得到弯曲强度下降到75%时的使用寿命。结论 该复合材料在大气暴露方式下的自然老化程度最大,在海水全浸方式下的自然老化程度最小。在老化过程中,主要是复合材料表面的不饱和聚酯树脂老化、脱离。以弯曲强度下降到75%为失效指标,计算得出复合材料的寿命为93.3个月。

树脂基复合材料模拟海洋环境长期老化及失效行为

目的实现高性能树脂基复合材料的环境适应性评价和使用寿命预测。方法选取玻璃纤维增强不饱和聚酯(GF/197S)与玻璃纤维增强乙烯基脂(GF/905-2)2种树脂基轻质复合材料,开展模拟海洋环境实验室盐雾、湿热和盐水浸泡环境9600 h的加速老化试验。基于4种力学性能(拉伸强度、弯曲强度、压缩强度及层间剪切强度)开展材料老化行为规律研究,利用傅里叶变换衰减全反射红外光谱(ATR-FTIR)对树脂基体在3种加速老化环境中的分子链段与官能团变化情况进行分析,得到基体树脂的老化机理。利用外观、超声扫描成像、SEM分析树脂纤维界面的变化情况,明确树脂/纤维界面的失效模式。利用差示扫描量热分析(DSC)与热重分析(TG)分析3种加速老化方式对玻璃纤维增强树脂复合材料(GFRPC)的玻璃化转变温度(t_(g))与热质量损失的影响。结果3种老化方式对树脂基体的老化影响顺序依次为70℃/95%RH湿热、35℃盐雾、常温盐水浸泡。结论得到了先进轻质树脂基复合材料的模拟海洋环境老化行为、失效模式以及树脂基体的老化机理,为实现高性能树脂基复合材料的环境适应性评价和使用寿命预测奠定了基础。

建筑用聚酯玻纤复合材料的制备与性能分析

选择不饱和聚酯树脂为基体材料,以玻璃纤维为增强相,采用模压成型工艺制备了不同玻璃纤维掺杂量(0,5%,10%,15%和20%(质量分数))的聚酯玻纤复合材料,分析了玻璃纤维含量对复合材料的微观形貌、热稳定性、拉伸性能和弯曲性能的影响。结果表明,聚酯玻纤复合材料中玻璃纤维和不饱和聚酯主要以物理作用为主,适量的玻璃纤维掺杂后能与聚酯基材紧密结合,分布具有方向性。随着玻璃纤维掺杂量的增大,聚酯玻纤复合材料的分解温度先增大后减小,且耐热性能提高,当玻璃纤维的掺杂量为15%(质量分数)时,复合材料的T 50%达到最大值368.47℃。力学性能测试表明,随玻璃纤维掺杂量的增大,复合材料的拉伸强度和冲击强度先增大后减小,断裂延伸率和弯曲强度持续降低,当玻璃纤维的掺杂量为15%(质量分数)时,复合材料的力学性能最优,拉伸强度最大为26.1 MPa,断裂延伸率为2.6%,冲击强度达到最大值8.1 MPa,弯曲强度为30.5 MPa。

复合材料的真空辅助成型工艺研究

研究了导流介质、脱模介质等工艺要素对真空辅助成型工艺的影响。结果表明,高渗透率的导流介质和脱模介质均能有效提高树脂的充模速度;所研制的新型导流介质能够有效控制树脂的流动状态。采用真空辅助成型工艺成型的复合材料的性能与模压工艺成型的复合材料的性能相当。

高性能UP/GF复合材料井盖的开发与应用

采用玻璃纤维(GF)和不饱和聚酯树脂(UP)为原料,研制了高性能复合材料井盖。介绍了该复合材料井盖的材料性能、结构设计及生产工艺。通过与铸铁、水泥、再生橡胶等不同材质井盖的性能对比,表明复合材料井盖具有承载能力高、抗震性能好、尺寸稳定、耐腐蚀、耐老化、使用寿命长、性价比高等诸多优点,并且生产工艺简单,可完全替代铸铁井盖,具有较高的推广应用价值。

2006-2007年国内外不饱和聚酯树脂工业进展

综述了2006-2007年国内外不饱和聚酯树脂和原料的生产、供应、消费以及产能扩充情况。介绍了不饱和聚酯复合材料研究及应用进展、不饱和聚酯节能降耗、环保新工艺及在提高不饱和聚酯树脂力学性能、耐热性、防腐蚀性、阻燃性方面的研究进展以及新型水性光固化不饱和聚酯树脂。

废旧线路板粉料增强不饱和聚酯复合材料力学性能

以废旧线路板回收处理过程中得到的塑料粉料作为增强填料，采用模压成型的方法制备成不饱和聚酯复合材料。改变填料形状、加入量及尺寸大小，研究其对复合材料性能的影响。结果表明：用废弃粉料与短切玻璃纤维作为组合增强体制得的不饱和聚酯复合材料的力学性能远大于仅用废弃粉料作为增强体的力学性能；颗粒长度为1～3mm的纤维状粉料对复合材料性能的提高远远大于颗粒长度为0．25mm的纤维状粉料对复合材料性能的提高，且填充量也较大，质量分数可达65％，弯曲强度和冲击强度可达150MPa、18kJ／m^2。

苎麻纬编针织复合材料的研制

用 RTM成型工艺对用苎麻和玻璃纤维设计、织造的米拉诺罗纹加衬纬和变化畦编加衬纬纬编针织物与树脂进行复合 ,并测试和分析了织物复合前后的拉伸性能。结果发现 ,纬编针织复合材料的拉伸性能主要取决于衬纬纱 ;变化畦编加衬纬复合材料的强度比米拉诺加衬纬的高 ;

溶剂法回收玻璃纤维/环氧复合材料的试验研究

为了解决现有化学回收法技术不适用于热固化体系的问题,采用溶剂法从玻璃纤维/环氧复合材料成功回收了玻璃纤维.在90℃的8mol/L分解液作用下,12h即可将复合材料中的环氧树脂基体分解为低分子含苯环有机物,回收到外观清洁的玻璃纤维.当分解温度为90℃,酸液浓度为8mol/L,投料比为6g:100mL时,回收纤维的单丝拉伸强度损失为5.2%.以分解时间、回收纤维强度损失为考查指标,利用正交实验法对分解条件进行优化,得到各因素的影响次序:浓度为最重要因素、温度次之、投料比影响最小.

温度和压力对玻璃纤维增强环氧复合材料吸湿特性的影响

采用称量法研究了温度、压力对浸泡在水中的GF/E-51试件吸湿性的影响;通过短梁剪切实验研究了温度、压力和浸泡时间对GF/E-51剪切强度的影响,使用体视显微镜观察了浸泡60d后GF/E-51的截面形貌。结果表明:温度对试件的吸湿影响较大,与30℃时相比,50℃时的平衡吸湿量增了145.0%,扩散系数增加了47.6%,50%吸湿量以前的平均吸湿速率增加了3倍,温度升高,加速了GF/E-51试件吸湿由Fick扩散到非Fick扩散的转变;压力对复合材料吸湿及吸湿试样的剪切强度有明显的影响:压力升高,抑制了树脂基体的溶胀,延缓了GF/E-51试件吸湿由Fick扩散到非Fick扩散的转变,减轻了溶胀对剪切强度影响,浸泡60d后,剪切强度保留率保持不变,但5atm/30℃水中试件剪切强度保留率比1atm/30℃条件下高3.97%、比1atm/50℃条件下高5.17%。

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。