碳纤维三维网络体增强环氧树脂复合材料的性能

以酚醛树脂粘结短切碳纤维(SCF)并炭化制得碳纤维三维网络增强体(CFNR),再采用真空袋成型法浸入环氧树脂(EP)制得新型EP/CFNR复合材料。通过显微镜观察CFNR和复合材料的微观结构,采用万能试验机测试力学性能,以及用电阻仪测定导电性能等方法对复合材料进行了评价。结果表明,炭化后的酚醛树脂将SCF粘结成连续的三维网络结构,EP/CFNR复合材料中SCF间有明显可见的炭质粘结点;当SCF质量分数为7.3%时,EP/CFNR复合材料较纯EP,EP/SCF复合材料的弯曲强度分别提高33%,29%,压缩强度分别提高23%,10%,同时,其体积电阻率是EP/SCF复合材料的1/45。     

EP/BMI树脂基碳纤维复合材料的制备与性能表征

以环氧树脂(EP)、双马来酰亚胺(BMI)、4,4’-二氨基二苯砜(DDS)和短切碳纤维(SCF)等为主要原料制备了EP/BMI/DDS/SCF复合材料,并研究了SCF添加量对复合材料力学性能和热性能的影响。结果表明,当SCF添加量为0.25 %(质量分数,下同)时,EP/BMI/DDS/SCF复合材料的力学性能提高最大,其拉伸强度、弯曲强度、弯曲模量和缺口冲击强度比未添加SCF时的EP/BMI/DDS复合材料分别提高了48.52 %、32.15 %、25.77 %以及150.91 %;此外,SCF的加入有助于提高复合材料的热性能。     

用于水润滑轴承的聚氨酯/环氧树脂/短切碳纤维复合材料的制备及摩擦学性能

以环氧树脂(EP)和短切碳纤维(SCF)为改性剂对聚氨酯(PU)进行改性,制备了PU/EP/SCF复合材料,研究了复合材料的物理机械性能和摩擦学性能。结果表明,当SCF质量分数为7.5%时,PU/EP/SCF复合材料具有最佳的物理机械性能和摩擦学性能,拉伸强度和扯断伸长率分别为16.5 MPa、157.5%,干摩擦条件下摩擦系数和磨损率分别为0.48和1.44×10~(-4)mm~3/(N·m)。     

PLA/PBAT/绢云母复合材料制备与性能

采用熔融共混技术制备了聚乳酸(PLA)/聚己二酸对苯二甲酸丁二酯(PBAT)复合材料、PLA/绢云母复合材料以及PLA/PBAT/绢云母三元复合材料,以拉伸强度、弯曲强度、断裂伸长率和冲击强度为参数,探究了PBAT和绢云母的用量对PLA基复合材料力学性能的影响.实验结果表明,PLA/PBAT/绢云母复合材料的最佳质量配...     

SCF/rGO协同改性环氧树脂的力-电性能的研究

将还原氧化石墨烯(rGO)与短切碳纤维(SCF)按一定比例混合,制备SCF/rGO协同改性环氧树脂复合材料,研究添加rGO前后复合材料的体积电阻率和硬度变化,分析SCF和rGO含量对复合材料力电性能的影响。结果表明,添加rGO前,短切碳纤维/环氧树脂复合材料(SCF/EP)的体积电阻率随SCF含量的增加逐渐减小,整体变化趋势分为三个阶段,同时其维氏硬度成对数比例上升。材料在拉伸应变小于0.2%时表现出线弹性行为,电阻变化率(ΔR/R_0)随应变呈现出先线性变化,后逐渐趋于指数变化的规律。添加rGO后,复合材料(SCF/rGO/EP)的电导率、维氏硬度和拉伸性能均显著提高,应变灵敏系数大幅下降,离散度大幅减小,说明rGO与SCF协同实现了导电网络的有效优化。     

绢云母在丁苯橡胶中的应用

以滁州绢云母为填料,将其改性后制备了改性绢云母/丁苯橡胶(SBR)复合材料,考察了复合材料物理机械性能的影响因素,并通过傅里叶变换红外谱(FTIR)表征了改性绢云母和复合材料。结果表明,在改性剂WD 81质量分数为2.0%、改性温度为90℃、改性时间为25 min以及改性绢云母用量为80份、硫化温度为150℃、硫化时间为12 min的条件下制得的改性绢云母/SBR复合材料的拉伸强度、扯断伸长率、撕裂强度和邵尔A硬度分别达到6.81 MPa、856%、28.04 k N/m和56;改性绢云母/SBR复合材料的官能团发生了加成聚合反应,改性剂起到"桥梁"作用,提高了绢云母对SBR基体的增强作用。     

改性绢云母对顺丁橡胶导热性能的影响

采用硬脂酸对绢云母进行表面改性,研究改性绢云母用量对绢云母/顺丁橡胶复合材料性能的影响.结果表明,随着改性绢云母用量的增大,复合材料的硫化速度加快,转矩和门尼粘度增大,加工性能下降;邵尔A型硬度、热导率和介电常数逐渐增大,拉伸强度、拉断伸长率、拉断永久变形、撕裂强度、表面电阻率和体积电阻率均先增大后减小,而击穿电压变化不大.     

类绢云母/SBR复合材料性能及其改性研究

研究类绢云母/丁苯橡胶(SBR)复合材料的硫化特性及物理性能。结果表明:添加类绢云母后的SBR胶料物理性能提高;类绢云母对SBR的补强效果优于碳酸钙、高岭土和沉淀硫酸钡等通用无机填料;偶联剂改性有利于提高类绢云母/SBR复合材料的性能,偶联剂Si69的改性效果较突出;当偶联剂Si69用量为类绢云母用量的10%时,胶料的拉伸强度和耐磨性能较好。     

磨碎碳纤维增强环氧树脂复合材料的性能研究

利用两种不同的磨碎碳纤维粉体(CFP)填充环氧树脂(EP),通过熔融共混制备了EP/CFP复合材料。研究了CFP含量、长度与复合材料导电性能、力学性能和热稳定性能的关系,并考察了材料断口形貌。研究表明:P-100型CFP填充的质量分数为25%时,EP/CFP材料的体积电阻率为1.34×106Ω·cm;拉伸强度、拉伸弹性模量、冲击强度和弯曲强度较EP分别提高了124%、186%、98.7%和66.7%,同时材料的热稳定性也略有提高。     

EP/CFDSF/CNTs复合材料的力学性能和电学性能

采用浓硝酸和浓硫酸改性碳纳米管(CNTs),然后以环氧树脂(EP)为基体、碳纤维双层间隔织物(CFDSF)为增强体制备了EP/CFDSF/CNTs复合材料,研究了改性CNTs含量对EP/CNTs和EP/CFDSF/CNTs复合材料力学性能及电学性能的影响。结果表明,随改性CNTs含量增加,两种复合材料的弯曲强度和缺口冲击强度均先升高后降低,当改性CNTs的含量为2.5份时,两种复合材料的力学性能最好,EP/CFDSF/CNTs复合材料的弯曲强度和缺口冲击强度分别为145.18 MPa和18 kJ/m~2,分别较EP/CNTs复合材料提高了12.5%和18.4%。随改性CNTs含量增加,两种复合材料的体积电阻率降低,当达到渗滤阈值即改性CNTs的含量为2.5份后下降明显,EP/CNTs复合材料的体积电阻率为25.9Ω·cm,而EP/CFDSF/CNTs复合材料的体积电阻率为20.85Ω·cm。     

CPVC／PVC／CPE三元共混改性的应用

研究了CPVC/PVC/CPE三元共混物的物理力学性能和流变性能。结果表明 :共混物的维卡软化温度、拉伸屈服强度和熔体粘度随CPVC用量的增加而明显增加 ;CPE的用量为 4～ 8份时可明显改善共混物的冲击强度     

Enhanced dielectric and energy-storage properties in ZnO-doped 0.9(0.94Na0.5Bi0.5TiO3−0.06BaTiO3)−0.1NaNbO3 ceramics

[0.9(0.94Na_0.5Bi_0.5TiO₃?0.06BaTiO₃)?0.1NaNbO₃]-xZnO (NBT-BT-NN-xZnO, x=0, 0.5 wt%, 1.0 wt%, 1.5 wt%, and 2.0 wt%) ferroelectric ceramics were fabricated using a conventional solid-state reaction method. The effects of ZnO content on dielectric, energy-storage and discharge properties were systematically investigated. Dielectric constant and difference between maximum and remanent polarization were significantly improved by ZnO doping. Dielectric constant of NBT-BT-NN-1.0-wt% ZnO was 3218 at 1 kHz and room temperature, i.e. one time bigger than that of pure NBT-BT-NN ceramic. As a consequence, a maximum energy-storage density of 1.27 J/cm³ with a corresponding efficiency of 67% was obtained in NBT-BT-NN-1.0-wt% ZnO ceramic. Moreover, its pulsed discharge energy density was 1.17 J/cm³, and 90% of which could be released in less than 300 ns. Therefore, ZnO doped NBT-BT-NN ceramic with a large energy-storage density and short release time could be a potential candidate for applications in high energy-storage capacitors.     

Structural,morphological and optomagnetic properties of GO/Nd/Cu-Mn ferrite ternary nanocomposite

Graphene oxide (GO)/neodymium (Nd)/Cu_0·5Mn_0·5Fe₂O₄ ternary nanocomposite was prepared by sonochemical method and modified Hummer's method. The crystal structure and structural parameter of Cu_0·5Mn_0·5Fe₂O₄ (CMF) nanoferrites were changed with the addition of Nd³⁺ and GO. Raman active modes of the GO and ferrite system were observed from Raman spectra. The surface oxidation state (C 1s, O 1s, Cu 2p, Mn 2p, Fe 2p, and Nd 3 d) and their respective binding energies of the prepared nanocomposite were discussed. Different surface morphologies were acquired for CMF, Cu_0·5Mn_0·5Fe_1.85Nd_0.15O₄ (CMNF), GO, and GO/Cu_0·5Mn_0·5Fe_1.85Nd_0.15O₄ (GCMNF) ferrite nanocomposites. The absorption of the Cu-Mn nanoferrite (red region) shifted into the blue region with the addition of Nd³⁺ and GO. The magnetic parameters were changed with doping of Nd into CMF and GO in CMNF nanoferrite. It was found that the high anisotropy energy values of the CMNF and GCMNF ferrite nanocomposites could be used for electromagnetic wave-absorbing application.     

羰基铁粉/锶铁氧体/MVQ吸波复合材料的制备与性能研究

以羰基铁粉与锶铁氧体为吸波填料制备羰基铁粉/锶铁氧体/甲基乙烯基硅橡胶(MVQ)吸波复合材料,研究羰基铁粉/锶铁氧体并用比对羰基铁粉/锶铁氧体/MVQ吸波复合材料性能的影响。结果表明,羰基铁粉/锶铁氧体/MVQ复合材料吸波峰处于羰基铁粉/MVQ和锶铁氧体/MVQ复合材料之间,在填料总体积分数不变的前提下,随着羰基铁粉用量的减小,复合材料吸波峰小于-10 dB的带宽先增大后减小、吸波峰向高频方向移动、拉伸强度和拉断伸长率变化不大、压缩永久变形减小、动态性能提高。     

聚乳酸/聚丙烯/淀粉复合材料的制备及性能研究

采用模压成型制备了聚乳酸(PLA)/聚丙烯(PP)和PLA/PP/淀粉两种复合材料.主要研究了复合材料的热性能、力学性能和降解性能.结果表明:对于PLA/PP复合材料而言,复合材料的熔融温度先增加后降低,结晶度随PLA的含量增加而变大,而且出现了结晶双峰.力学性能相较与纯PLA,断裂伸长率明显提高,拉伸强度有所下降,最...     

The role of Eu2O3 and CeO2 on the phase formation,infrared emission and magnetic properties of Co0.6Zn0.4Fe2O4 ceramics by a solvothermal method

Nanosized Eu₂O₃ and CeO₂ co-addition CoZn ceramics have been achieved via a hydrothermal method by adjusting the mol ratios of Eu and Ce. The as-prepared samples were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Vibrating sample magnetometer (VSM) and Infrared emission measurement (IRE-2). The particle morphologies of the as-prepared samples evolve from spherical, to self-assembled nanoparticles, and irregular nanoparticles when the mol ratios (x) of Eu and Ce was changed from 0:10 to 10:0. Correspondingly, the main phases of the as-prepared samples change from both cubic spinel CoFe₂O₄ and CeO₂, pure cubic cerianite CeO₂, to amorphous. Meanwhile, the as-prepared samples appear transformed from a ferromagnetic behavior with a saturation magnetization 66.4 emu/g to a paramagnetic behavior with a saturation magnetization of 0.55 emu/g at turning point x=3.5:6.5. While the infrared emissivity is increasing as the x from 0:10 to 3.5:6.5, reach the maximum at 3.6:6.4, and then remain stable when further increasing x till 10:0. Those may be due to the amorphous tendency rising and the particle sizes gradual decreasing with x increasing from 0:10 to 10:0. What is more important is that the solvothermal method is proved to be an efficient way to prepare CoZn nano-ceramics in this study which may open new pathways to magnetic and far infrared therapy.     

Eu掺杂对Bi5Fe0.5Co0.5Ti3O15陶瓷电磁性能的影响

用传统固相烧结法制备了Bi5–xEuxFe0.5Co0.5Ti3O15(BEFCT–x:x=0,0.35,0.55,0.85)陶瓷样品,对比研究了它们的结构和电磁性能。X射线衍射分析表明:掺杂未导致明显杂相,材料的剩余极化(2Pr)随掺杂量的增加呈先增加后减小的变化趋势,在Eu掺杂量为0.55时,材料的2Pr达到最大值,为11.2μC/cm2,升幅达143%,可以由Eu掺杂导致氧空位的抑制和铋氧层的破坏所形成的竞争机制解释。随Eu含量的增加,材料的剩余磁化单调上升,最大达到0.28 A m2/kg,比未掺杂时增加了2个数量级,从晶格失配、耦合增强以及共生结构等方面的综合效果解释了这一现象。材料的介电温度谱显示,Eu掺杂未明显损害材料的热稳定性,Eu掺杂所导致的介电损耗行为可能与氧空位或其他点缺陷有关联。     

聚丙烯/石墨烯复合材料性能研究进展

利用石墨烯优异的导电率、断裂强度等物理性质,可使聚丙烯(PP)/石墨烯复合材料表现出更好的力学性能以及导电性能。主要概述了PP/石墨烯复合材料的合成方法及其性能改进研究进展,并对PP/石墨烯复合材料的未来发展做了展望。     

石墨/炭黑/EPDM复合材料的性能研究

研究石墨/炭黑/EPDM复合材料的物理性能、动态力学性能和导电性能.结果表明:石墨对炭黑填充EP-DM复合材料具有补强作用,并显著提高其导电性能;石墨/炭黑/EPDM复合材料的电导率-压力曲线表现出“山峰”形变化趋势,升高温度或增大石墨用量时该峰向低压力区移动;石墨用量越大,复合材料电导率的温度依赖性越强,石墨粒子滑移...     

硅橡胶/顺丁橡胶/乙丙橡胶共混材料的研究

针对硅橡胶具有较高耐热性．但力学性能差；三元乙丙橡胶（EPDM）力学性能较好，但互粘性较差；顺丁橡胶（BR）弹性好．但加工性能堇的特点，提出了将硅橡胶、三元乙丙橡胶与顺丁橡胶共混的方法，制成共混材料；再通过测定样品的性能，确定共混的最佳配比。结果表明：BR与EPDM、硅橡胶相客性较好，可达到共硫化；硅橡胶／BR／EPDM质量比为20／30／50时，共混物的物理机械性能和老化性能较好；用过氧化二异丙苯（DCP）／硫磺作硫化剂要好于用硫磺、过氧化二苯甲酰（BPO）和硫磺／BPO硫化剂。试样的耐热老化性能、邵尔A型硬度和扯断伸长率较好，其中样品的综合性能具备了硅橡胶、顺丁橡胶和三元乙丙橡胶的优点。