导电填料结构对氯化丁基橡胶基压电阻尼复合材料性能的影响

以氯化丁基橡胶(CIIR)作为基质材料、锆钛酸铅(PZT)为压电填料,分别以碳纳米管(CNTs)和导电炭黑(CB)作为导电填料,通过机械共混法制备了CNTs/PZT/CIIR和CB/PZT/CIIR两种压电阻尼复合材料。采用扫描电镜考察了导电填料在基质中的分散状况及其与基质的相容性,通过动态热机械分析和弹性体测试系统的测试探讨了导电填料的结构对复合材料压电阻尼性能的影响规律。结果表明,与CB相比,CNTs在基质中出现了严重的团聚,这导致其所制备复合材料的拉伸强度未达到预期效果。用量相同时,添加了CNTs复合材料的损耗因子峰值要小于填充CB者,但是其阻尼系数较大;随着导电填料用量的增加,两种复合材料的损耗因子峰值均呈下降趋势,而阻尼系数先略微减小然后增大。     

压电陶瓷/NBR复合材料压电与吸声性能研究

以NBR为基体材料,以压电陶瓷为功能相制备压电橡胶复合材料,并对其压电与吸声性能进行研究.结果表明,复合材料的压电常数(d33)随压电陶瓷用量的增大而增大,当压电陶瓷用量为5210份时,d33达到3.1×10-11C·N-1,并随着极化时间的延长而增大,随着极化温度的升高先增大后减小,且最佳极化时间为25min,最佳极化温度为80℃.压电橡胶复合材料的吸声因数在2～3 kHz的频率内随着复合材料压电常数的增大而增大,碳纤维的加入使复合材料内部形成了一定的导电网络,提高了复合材料的吸声因数.     

聚氨酯基压电阻尼复合材料阻尼性能的研究

用绝缘电阻测试仪研究了以聚氨酯(PPG2000)为基体材料,锆钛酸铅(PZT)为压电填料,导电炭黑(CB)为导电填料的压电复合阻尼材料的导电性能。以渗流理论分析了对于PPG2000导电炭黑的渗流阈值,以及PZT的加入对导电炭黑渗流阈值的影响。采用动态力学性能分析(DMA)技术对聚氨酯压电陶瓷复合阻尼材料的阻尼性能进行研究,分析了导电性能对其阻尼性能的影响。     

PMMA/PZT复合材料的制备及电性能研究

采用有机物燃烧法制备了不同孔隙率多孔PZT陶瓷基体,在此基础上通过原位聚合法制备了PMMA/PZT压电复合材料。研究了复合材料的形貌与压电陶瓷体积含量对复合材料介电性能和压电性能的影响。结果表明,复合材料仍存在一定的孔隙率,随着PZT体积含量的增加,电性能参数呈非线性增加。当PZT体积含量为75%时,d33值达98 PC/N。     

压电陶瓷/聚氨酯智能阻尼复合材料的制备与表征

以热塑性聚氨酯弹性体为基材,压电陶瓷粉和导电石墨为功能相,制备了压电陶瓷/聚氨酯智能阻尼复合材料,并对其结构性能进行表征分析。结果表明,压电陶瓷粉添加质量份为20和40时,能得到具有较好分散性的压电陶瓷/聚氨酯智能阻尼复合材料;当压电陶瓷粉添加质量份为40时,tgδ峰值达到最大,说明制得的复合材料具有良好的阻尼性能;相对介电常数随着压电陶瓷粉添加量的增加而增加,当压电陶瓷粉质量份为40时,相对介电常数为15.06。热性能测定结果表明,加入压电陶瓷粉后,复合材料的软化点明显提高。     

丁腈橡胶/铌镁锆钛酸铅/碳纤维复合材料的介电性能和压电性能

以丁腈橡胶(NBR)为基体,铌镁锆钛酸铅(PMN)粉体为分散相,碳纤维(CF)为导电填料,制备了压电复合材料,研究了复合材料的压电性能及介电性能。结果表明,80%以上PMN粒子的粒径为0.5~2.0μm,填充密度约为6.6g/cm3;当填充CF体积分数小于5%时,复合材料的击穿电压受填充CF用量的变化影响不大,当填充CF体积分数达到10%时,复合材料的击穿电压下降到未填充CF复合材料的1/3~1/2,填充CF最佳体积分数为5%;当填充PMN体积分数增至40%后,复合材料的纵向压电应变常数(d33)随PMN用量的增加而增大;适当地延长极化时间和增加极化电压有利于提高d33,最佳极化电压为7kV/mm,最佳极化时间为25min;复合材料的介电常数(ε)随填充PMN用量的增加而增大;当CF用量为0时,复合材料的ε与介电损耗(tanδ)的变化趋势相反;当填充CF体积分数为5%时,复合材料不但具有较高的ε,而且具有较高的tanδ。     

聚氨酯/碳纳米管复合材料的制备与表征

采用预聚体法制备了聚氨酯/碳纳米管(PU/CNTs)复合材料,考察了该复合材料中CNTs含量对复合材料电性能、力学性能和热性能的影响及复合材料的微观结构。结果表明,碳纳米管在聚氨酯体系中能够较好地分散;扩链/交联剂对PU/CNTs复合材料的导电性能影响较大,TMP比MOCA交联的PU/CNTs复合材料导电性能好;用TMP作交联剂制备的PU/CNTs复合材料的力学性能明显低于以MOCA为扩链剂的PU/CNTs复合材料的力学性能;随着CNTs的加入,PU/CNTs复合材料储能模量和耗能模量明显增加,复合材料的阻尼性能大幅度提高。     

制备条件对压电陶瓷/丁腈橡胶复合材料介电性能和压电性能的影响

以丁腈橡胶为基质、铌镁锆钛酸铅粉体为分散相,制备了压电陶瓷/丁腈橡胶复合材料,研究了极化条件和成型压力对复合材料介电性能和压电性能的影响.结果发现,复合材料的介电常数随极化电场强度、极化温度和成型压力的增加而增加;压电常数随极化电场强度和成型压力的增加而增加,而在极化温度为80 ℃时出现最大值.     

IPN/PMN压电阻尼材料性能的研究

综合利用铌镁锆钛酸铅(PMN)压电陶瓷、互穿聚合物网络(IPN)两种材料各自的优点,设计制备了以丙烯酸酯IPN体系为基体的聚合物基压电阻尼复合材料。研究发现:PMN的加入,不仅提高了其阻尼性能,对复合体系的热稳定性也有贡献。经万能击穿装置极化后,研究压电常数与PMN含量的关系,用动态力学分析仪研究发现其阻尼性能更加优越。     

PZT/PVDF体系压电复合材料的介电和压电性能研究

采用复合材料热压工艺,制备了0-3型PZT/PVDF(钛锆酸铅/聚偏二氟乙烯)压电复合材料。系统地研究了PZT体积分数对材料介电、压电性能的影响,并与Furukawa等人的理论预测进行了对比。结果显示在PZT体积分数为70％时,获得了性能优良的压电复合材料。在压电陶瓷高含量区,部分压电陶瓷颗粒相互联接,形成了类似0-3(1-3)型连通形式,获得了压电和介电性能优良的压电复合材料。     

PVDF/PZT/CB高分子复合材料动态机械性能研究

本文应用动态机械性能分析方法,研究了PVDF/PZT/CB复合体系的贮能模量和损耗模量并分析了其减振性能,结果表明该复合材料既有较好的力学性能,又有较理想的减振功能.     

Damping characteristics of chlorobutyl rubber/poly(ethyl acrylate)/piezoelectric ceramic/carbon black composites

In this study, a new kind of damping composite consisting of chlorobutyl rubber, poly(ethyl acrylate), piezoelectric ceramic (PZT), and carbon black (CB) was prepared, and some efforts were made to characterize the damping behavior and explore the damping mechanism. The damping behaviors of the composites were mainly decided by the contents of CB and PZT. When an external vibration was exerted on the composites, the mechanical energy of vibration was transformed into electric energy by PZT; if the resistance was adjusted to a suitable range by the variation of the CB content, the composites could behave as semiconductors: the electric energy could not be transferred to the surface of the material but rather was dissipated as thermal energy. For this system, when the contents of CB and PZT were between 10 and 30 vol %, respectively, the volume resistivity was between 10⁵ and 10^9.5 Ω cm, and a good damping performance could be achieved. On the basis of the results, a theoretical model is proposed to explain the damping performance of the composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚氨酯/聚甲基丙烯酸酯交联聚合物合成与力学性能的研究

采用相对分子质量不同的聚氧化丙烯二醇(PPG)与甲苯二异氰酸酯合成聚氨酯预聚物,将该预聚物用甲基丙烯酸-2-羟乙酯(HEMA)封端后与甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA)进行自由基聚合得到一系列交联聚合物。利用红外光谱(FT-IR)、力学性能测试及动态力学热分析(DMTA)等手段对交联聚合物进行了表征。聚氨酯/聚甲基丙烯酸甲酯(PU/PMMA)交联聚合物具有较高的阻尼值和较宽的阻尼温域,当两组分的质量比为5∶5时,阻尼性能最佳。PU/PMMA交联聚合物的拉伸强度随聚甲基丙烯酸甲酯含量的增加而增加,断裂伸长率随其含量的增加而减小;聚氨酯/聚甲基丙烯酸丁酯(PU/PBMA)交联聚合物的拉伸强度随聚甲基丙烯酸丁酯含量的增加而减小,断裂伸长率随其含量的增加而增大。     

PEG/PTMG/IPDI体系聚氨酯耐热及耐紫外线性能研究

对PEG/PTMG/IPDI体系的聚醚型脂肪族聚氨酯(PU)材料耐热和耐紫外线性能进行研究。研究表明,与PEG相比,PTMG含量的增加会显著提高树脂的拉伸强度、耐热性以及耐紫外线性能。当PU树脂软段全部用PEG时,DMA测试结果显示树脂材料熔融温度低于120℃;在35℃时紫外线照射72 h后,树脂快速分解,力学强度大幅损失。     

Polyurethane/poly(vinylidene fluoride)/MWCNT composite foam for broadband airborne sound absorption

A polyurethane/poly(vinylidene fluoride)/multi-walled carbon nanotubes (PU/PVDF/MWCNT) (83/15/2) composite foam was designed and fabricated. The foam exhibited high airborne sound absorption performance in a wide-frequency range. The sound absorption coefficient reached the value of 0.85 at 1 kHz, which is a significant improvement over PU foam. It was found that PVDF formed a separate immiscible phase and part of it was crystallized in a polar phase in the PU scaffold in the PU/PVDF/MWCNT composite, which could benefit the sound absorption performance by introducing interfacial damping and local piezoelectric damping effects. The introduction of the conductive MWCNT filament in the composite foam further improved sound absorption, possibly by facilitating the dissipation of the electrical charges generated from local piezoelectric effect and enhancing both the interfacial damping effect and local piezoelectric damping effect. With PU as the main ingredient, the fabrication scalability of the foam can be improved with significantly reduced material and production cost in comparison with PVDF foam. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47868.     

Piezoelectric and Dielectric Properties of Acrylonitrile Butadiene Rubber/Lead Magnesio-Niobate Piezoelectric Ceram

A new composite with special piezoelectric property was prepared by using lead magnesio-niobate piezoelectric ceram powders (PMN) as dispersing phase in acrylonitrile butadiene rubber (NBR) matrix. The dielectric and piezoelectric properties of the composite were studied. The result shows that the particle size of 80% of PMN ceram powders was 0.5–2 µm. The piezoelectric constant (d₃₃) of the composite increased with increasing volume fraction of PMN, and the max piezoelectric constant is 33 when the PMN volume fraction is 85%. Appropriate delay of polarizing time with increasing polarizing voltage could be helpful to improve the d₃₃ value. The optional polarizing condition is 25 min, 7–8 kv/mm, and 80°C. The dielectric constant increased with the increasing of the PMN volume fraction. Polarized time, polarized voltage, and polarized temperature have no effect on the dielectric constant.     

扩链剂对PPG-1000/MDI体系聚氨酯弹性体阻尼性能的影响

以聚氧化丙烯二醇(PPG-1000)、MDI-50与不同的二醇扩链剂采用二步法合成PPG-1000/MDI体系的聚氨酯(PU)弹性体,并对其阻尼性能进行了测试。结果表明,扩链剂对PPG-1000/MDI体系的聚氨酯弹性体的阻尼性能有明显影响。加入含侧甲基和醚键的扩链剂在不同程度上提高了聚氨酯弹性体的阻尼因子(tanδ),拓宽其阻尼温域。因此选择适宜的扩链剂对调节聚氨酯弹性体的阻尼温域具有一定的意义。     

Piezoelectric properties and damping behavior of highly loaded PZT/polyurethane particulate composites

In this study, using a solution casting process, thermoplastic polyurethane elastomer (TPU) composites containing different contents of lead zirconate titanate (PZT) ferroelectric particles were produced. The damping treatment of composites at high volume of fillers was investigated. SEM micrographs showed that PZT particles had a proper distribution in the PU matrix. Differential scanning calorimetry (DSC) thermograms indicates that melting enthalpy decreases by raising PZT filler content. The results of the dynamic mechanical thermal analysis (DMTA) proved that the magnitude of loss factor (tan δ) strongly depends on PZT content, and it decreased from 0.51 to 0.27 as PZT content increased. The value of E₀ increases to 0.32 GPa in the composite reinforced with 50 v% of PZT. The role of PZT on the acoustic behavior of TPU was measured using the acoustic absorption coefficient (a). The results showed that as PZT content increased from 0 to 50%, the acoustic absorption coefficient reached 0.25 at 6000 Hz frequency. The composites of PZT/PU with 0–3 connectivity were poled, and the optimal poling conditions that could be applied without sample breakdown were studied. Moreover, we prepared composites containing 70 vol% PZT particles by modifying the particles. Modification of PZT particles caused a decrease in both d₃₃ and g₃₃ constants of the PZT/PU composites.