碳纤维增强羟基磷灰石/环氧树脂复合材料的制备与力学性能

采用树脂传递模塑(RTM)工艺制备了碳纤维增强环氧树脂以及碳纤维增强羟基磷灰石(HA)/环氧树脂两种复合材料，并测试了其力学性能。结果表明，RTM工艺可以基本保证环氧基体均匀浸入碳纤维织物内部。碳纤维增强HA，环氧复合材料的冲击韧性高于碳纤维增强环氧复合材料，而弯曲强度和弯曲模量低于碳纤维增强环氧复合材料。两种复合材料的弯曲强度远高于人体皮质骨，弯曲模量与皮质骨非常接近。动态力学分析(DMA)表明加入HA后，复合材料的贮存模量和内耗降低，玻璃化转变温度升高。     

碳纤维增强复合材料中改性木质素的应用

目的 解决碳纤维增强环氧树脂复合材料中由双酚A合成的环氧树脂成本高、危害环境与健康、耐化学性差的问题,使木质素代替双酚A合成环氧树脂来制备碳纤维复合材料。方法 通过综述木质素在环氧树脂合成中的改性方法与合成方案的研究进展,分析碳纤维复合材料成型工艺的优缺点。结论 采用不同方法对木质素进行化学改性,可在降低成本的同时提高热稳定性与耐化学性等各项性能。用改性或降解木质素来合成碳纤维复合材料的环氧树脂基体为碳纤维增强材料的研究提供了新的研究方向,对碳纤维增强材料降低成本、提高性能和促进行业发展都具有积极作用。     

基于RTM工艺的纤维增强环氧树脂复合材料阻燃改性研究

制备了全新的阻燃定型剂DHQEP/ET3228,利用传统RTM工艺,实现了对纤维增强环氧树脂复合材料的阻燃改性。该定型剂的加入为预成型体提供出色的定型效果,回弹角测试中仅发生了1.24°的回弹,同时还可以有效提升复合材料的阻燃性能（LOI可达36.8%）。另外,阻燃定型剂可以参与环氧树脂的固化反应,使得阻燃定型剂的添加对复合材料的界面性能影响较小,保持了复合材料良好的层间剪切性能。     

高强玻纤增强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,以苯乙烯-马来酸酐共聚物(SMA)和环氧树脂(E-poxyresin)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SMA或环氧树脂,玻纤增强ABS复合材料的力学性能明显提高;SMA与环氧树脂复配有明显的协同效果,同时加入SMA和环氧树脂后的复合材料的性能更加优越,界面粘接性能得到很大的改善,在玻纤加入量为30%时,其拉伸强度、弯曲强度、冲击强度较未添加界面相容剂时分别提高了44%、29%、100%。     

芳纶纤维表面处理与浸渍工艺研究

采用H抽出法和橡胶弯曲疲劳试验法,考察了RF树脂的合成、RFL组成以及芳纶纤维浸渍工艺,研究了RFL组成及芳纶纤维浸渍工艺对纤维与橡胶的静态和动态粘合性能的影响。结果表明,第一浴采用环氧树脂或/和封闭异氰酸酯混合液,第二浴采用间苯二酚-甲醛-胶乳(简称RFL)双浴法,或者直接采用环氧改性RFL胶乳的一浴法都能有效地增加芳纶纤维界面粘合性能。     

Influence of Fiber Orientation and Fillers on Low Velocity Impact Response of the Fabric Reinforced Epoxy Composites

The low velocity impact response of the epoxy composite materials, which were reinforced with various hybrid contents, such as plain pure or hybrid fabrics (carbon, aramid and glass fibers and copper wires) and filler mixtures into the epoxy matrix (aramid powder, potatoes starch, barium ferrite and carbon black) was investigated using a drop weight impact machine. The aim of this study was to characterize and assess the effects of fiber orientation at various angles and filler mixtures into epoxy matrix on the impact response. All the tests were carried out at constant impact energy, namely 90.629 J. Results indicated that the fiber orientation at various angles has a positive effect on impact response, mainly in the case of aramid fabric reinforced composites. In terms of influence of fillers addition into matrix, it was obtained an improvement on the impact response of hybrid fabric reinforced composite as compared to the pure fabric reinforced composites.

     

苎麻纤维复合材料医用夹板的开发及智能化

以脱胶苎麻精干麻为增强材料,以环氧树脂和聚丙烯(PP)为树脂基体,分别制备出纤维含量不同的复合材料板。经测试分析发现,纤维含量的变化导致两种基体复合材料的压缩、弯曲以及剪切强度呈现不同的变化趋势。在纤维含量相同时,苎麻/PP较苎麻/环氧树脂复合材料的力学性能总体偏差,强度增量较低,纤维抽拔效果明显,断面破坏程度大,最终确定纤维含量在20%(体积分数,下同)时的苎麻/环氧树脂复合材料最适于制作医用夹板。在苎麻/环氧复合材料板上安装粘贴柱状硬块的传感器,实验证明测试结果可以达到理想的目的和要求。     

Processing of Bamboo Fiber Reinforced Plastic Composites

Anatomical properties of bamboo fiber, like chemical constituents and ultra structure establish bamboo as superior to other known natural ligno-cellulosic fibers. Bamboo fibers have been separated and sized in the form of fibers and strips. These fibers and strips mat (in the form of orthogonal mat) have been used to reinforce epoxy and unsaturated polyester (USP) resins. A process has been developed to cast bamboo fiber reinforced plastic (BFRP) unidirectional, bidirectional and multidirectional composites. The resulting material combine the strength and resilience of bamboo fiber with dimensional stability and moisture resistance of thermosetting resin.     

固化温度对亚麻纤维及其增强复合材料力学性能的影响

研究热压成型过程中,不同固化温度对亚麻纤维及其增强复合材料力学性能的影响。结果表明:亚麻纤维在120,140℃和180℃分别处理2h后单纤维拉伸性能发生不同程度的下降。环氧树脂E-51在120,140℃和180℃下固化2h后拉伸性能未发生明显变化。基于环氧树脂的单向亚麻纱线增强复合材料分别在120℃和140℃固化成型时,拉伸强度和冲击强度变化不大。但当固化温度达到180℃时,由于亚麻纤维在高温环境下损伤较为严重,其增强复合材料的拉伸强度和冲击强度均发生明显的下降。然而复合材料的拉伸模量随着成型温度的升高有一定幅度的提升。     

超临界二氧化碳对芳纶纤维的表面改性

针对芳纶纤维与树脂基体界面性能差及纤维原纤化的问题,采用超临界二氧化碳分散环氧树脂对芳纶纤维进行表面改性,研究超临界二氧化碳处理对芳纶纤维结构及性能的影响。结果表明超临界二氧化碳改性处理能够提高环氧树脂对芳纶纤维的浸润效果,利用超临界二氧化碳分散环氧树脂对芳纶纤维进行处理,可以在一定程度上提高芳纶纤维的性能并改善芳纶增强树脂基复合材料的界面性能。超临界二氧化碳处理能够提高芳纶纤维表面粗糙度及比表面积,且芳纶纤维性能不受影响。     

碳纤维复合材料界面残余应力的X射线衍射分析

根据碳纤维的晶体学特点,提出了利用X射线衍射技术分析碳纤维/树脂基复合材料界面残余应力的新方法。通过在环氧树脂基体中引入膨胀单体,改变界面残余应力,对本文提出的方法进行了验证     

Studies on mechanical,thermal and dynamic mechanical properties of untreated (raw) and treated coconut sheath fiber reinforced epoxy composites

The untreated (raw) coconut sheath fiber reinforced epoxy (UTCSE) composite and treated coconut sheath fiber reinforced epoxy (TCSE) composite have been fabricated using hand layup followed by compression molding technique. The prepared specimens were characterized by Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM) techniques. The prepared specimens are cut as per ASTM Standards to measure tensile, flexural and impact strengths by using universal testing machine and izod impact tester respectively. The treated coconut sheath fiber reinforced epoxy composite (TCSE) posses higher mechanical strength and thermal stability compared to untreated (raw) coconut sheath fiber reinforced epoxy composite (UTCSE). In the SEM fracture analysis, TCSE composite showed better fiber–matrix bonding and absence of voids compared to UTCSE composite.     

影响碳纤维增强复合材料摩擦系数的因素

本研究对碳纤维的体积比、分布方向及温度对增强热固性环氧树脂摩擦系数的影响作了试验及分析讨论 ,结果表明 ,碳纤维加入后可显著降低复合材料的摩擦系数 ,随碳纤维加入方式不同 ,碳纤维对摩擦系数的影响作用也不同     

氧化石墨烯有序排列对碳纤维增强环氧树脂复合材料低温性能影响

为了提高碳纤维增强环氧树脂复合材料在低温(77 K)循环条件下的微裂纹抗性,文中采用共沉淀法制备了具有良好顺磁性的四氧化三铁/氧化石墨烯(Fe_3O_4/GO),采用红外光谱、X射线衍射、扫描电镜、透射电镜等手段研究了Fe_3O_4/GO在环氧树脂基体中的有序排列对环氧树脂及碳纤维增强环氧树脂复合材料低温性能的影响。结果表明,Fe_3O_4/GO的有序排列可有效提高环氧树脂基体的低温力学性能及降低环氧树脂基体的热膨胀系数,并可明显改善碳纤维增强环氧树脂(CF/EP)复合材料的低温微裂纹抗性;相对于纯环氧树脂,改性环氧树脂的热膨胀系数和低温环境下的微裂纹密度分别降低了36.5%和37.5%。     

Processing of Functionalized and Pristine Carbon Nanotube Epoxy Composites with Silane-Treated Glass Fiber

In this work, an attempt has been made to study the bonding between the silane coupling agents and the glass fiber (GF) surface. The mechanical properties of the composites so obtained have been specifically analyzed. It has been experimentally found that epoxy silane (ES)-treated GF mat in a neat epoxy matrix showed considerable improvement compared to amino silane (AS)-treated GF. The effect of heat treatment on GF has also been looked into. Moreover, a new processing technique has been explored, which involves the use of amino functionalized nanotube (ACNT) and pristine nanotube (PCNT), homogeneously and uniformly dispersed in an epoxy matrix. Additionally, the effect of ES- and AS-treated GF in the presence of PCNTs and ACNTs has been studied and it has been found that AS shows strong interfacial adhesion in the ACNT matrix, whereas ES shows improved mechanical behavior in the PCNT matrix. The findings from this study have certainly helped us design improved fiber reinforced nanocomposites with enhanced mechanical properties suitable for marine structures.     

不同温度下环氧玻璃钢材料放气特性研究

为探究环氧玻璃钢材料在不同温度下的放气特性,以扩散放气模型为基础,建立了环氧玻璃钢材料放气速率随抽空时间变化关系的数学表达式,并结合实验数据拟合获得了其经验模型。同时,采用静态升压法对不同温度下环氧玻璃钢材料放气速率随抽空时间的变化关系进行了研究。结果表明,温度一定时,环氧玻璃钢材料的放气速率随着抽真空时间逐渐减小;温度升高,环氧玻璃钢材料放气速率增大,且放气速率随着抽真空时间呈现出指数衰减规律。此外,采用四极杆质谱仪分析了不同温度下环氧玻璃钢材料的放气成分,放气成分以H₂O为主,并含有微量的H₂、CO、N₂及O₂等。温度升高,玻璃钢材料放气各组分的占比无明显变化,表明温度对玻璃钢材料放气组分的占比几乎没有影响。     

热塑性塑料对环氧树脂热膨胀系数的影响研究

环氧树脂基体的热膨胀系数(CTE)对碳纤维增强环氧树脂层状材料的性能影响巨大,如何降低环氧树脂基体的CTE是提高碳纤维增强环氧树脂复合材料低温使用性能的关键。本研究采用聚对苯二甲酸丁二醇酯(PBT)、聚碳酸酯(PC)和聚醚酰亚胺(PEI)3种热塑性塑料改性环氧树脂,研究了这3种热塑性塑料对环氧树脂基体CTE的影响。结果表明:这3种热塑性塑料分子链中的羰基在环氧树脂固化过程中可与环氧分子侧链上的羟基形成氢键作用,从而加强了热塑性塑料与环氧树脂的界面作用;采用这3种热塑性塑料改性环氧树脂均可提高环氧树脂基体的玻璃化转变温度;相对于纯环氧树脂,PBT、PEI和PC改性的环氧树脂在玻璃化转变温度下的CTE分别降低了14.99%、17.44%和23.96%,但在玻璃化转变温度上的CTE均高于纯环氧树脂。     

导热型碳纤维增强聚合物基复合材料的研究进展

综述了导热型连续碳纤维增强聚合物基复合材料(CFRP)的研究与应用现状和进展,阐述了CFRP的声子导热和光子导热机理,介绍了不同铺层角度和铺层比的CFRP面内和厚度方向热导率计算模型及测试方法,分析了环氧树脂、氰酸酯、双马来酰亚胺等3类树脂体系和聚丙烯腈基(PAN)碳纤维、中间相沥青基碳纤维、气相生长碳纤维、碳纳米管纤维等4类增强体以及工艺方法等因素对CFRP热导率的影响。     

Improvements in mechanical properties of a carbon fiber epoxy composite using nanotube science and technology

Carbon fiber reinforced epoxy composite laminates, with strategically incorporated fluorine functionalized carbon nanotubes (f-CNTs) at 0.2, 0.3 and 0.5 weight percent (wt.%), are studied for improvements in tensile strength and stiffness and durability under both tension–tension (R = +0.1) and tension–compression (R = −0.1) cyclic loadings, and then compared to the neat (0.0 wt.% CNTs) composite laminate material. To develop the nanocomposite laminates, a spraying technology was used to deposit nanotubes on both sides of each four-harness satin weave carbon fiber fabric piece for the 12 ply laminate lay up. For these experimental studies the carbon fiber reinforced epoxy laminates were fabricated using a heated vacuum assisted resin transfer molding (H-VARTM®) method followed by a 2 soak curing cycle. The f-CNTs toughened the epoxy resin-fiber interfaces to mitigate the evolution of fiber/fabric-matrix interfacial cracking and delamination under both static and cyclic loadings. As a consequence, significant improvements in the mechanical properties of tensile strength, stiffness and resistance to failure due to cyclic loadings resulted for this carbon fiber reinforced epoxy composite laminate.     

碳纤维/铝/环氧复合板的初步研究

本文揭示了碳纤维/铝/环氧复合板的显微结构,比重、热胀性能与碳纤维含量的关系,探讨了增强组份的表面处理、碳纤维/铝的叠层结构设计、碳纤维含量、纤维混杂对复合板力学性能的影响。试验表明:碳纤维/铝/环氧复合板具有轻质、低热胀、高强度等特点,当碳纤维增强环氧的含量为55vol%时,它的拉伸,弯曲与剪切强度达到或超过芳纶纤维或玻璃纤维/铝/环氧复合板的相应值。