水性聚氨酯/十二烷基苯磺酸钠修饰多壁碳纳米管复合材料的制备与表征

以十二烷基苯磺酸钠(SDBS)修饰多壁碳纳米管(MWNTs)得到MWNTs-SDBS,采用溶液共混法,制备出水性聚氨酯/SDBS修饰多壁碳纳米管复合材料。探讨了MWNTs-SDBS含量对复合材料力学性能、热性能和电性能的影响及复合材料的微观结构。结果表明:碳纳米管在水性聚氨酯中分散均匀,明显提高了水性聚氨酯的力学性能和导电性。与纯水性聚氨酯相比,当MWNTs-SDBS含量为0.3%时,复合材料的拉伸强度和断裂伸长率分别提高9%和29%;当其含量为0.9%时,复合材料的电阻率提高接近9个数量级。此外,添加碳纳米管降低了聚氨酯软段的结晶性能。     

碳纳米管改性方法对其与聚氨酯的复合材料性能的影响

通过强酸回流、强碱球磨方法分别对碳纳米管进行了改性处理,采用溶液共混法制备了聚氨酯/碳纳米管复合材料。探讨了碳纳米管改性方法对复合材料的化学结构、微观形态、力学性能、热稳定性能以及导电性能的影响。结果表明,在聚氨酯基体中添加经化学改性处理的碳纳米管使复合材料的氢键增多,力学性能、热稳定性和导电性能都得到了提高。聚氨酯/强碱球磨处理碳纳米管复合材料中的氢键数目更多,综合性能也更优异,而且碳纳米管在聚氨酯基体中的分散更均匀。     

MWNTs/PUR复合材料的制备与气敏响应性研究

将端羧基丁二烯丙烯腈橡胶(CTBN)改性为多端羟基橡胶(f-CTBN)后,掺杂功能化多壁碳纳米管(MWNTs),与4,4′-二环己基甲烷二异氰酸酯(H12MDI)反应得到预聚物,再加入聚乙二醇(PEG6000)共聚合,得到一系列聚氨酯复合材料MWNTs/PUR;采用扫描电镜(SEM)、热失重(TG)等手段进行表征;考察了MWNTs含量、固化温度等因素对聚氨酯复合材料气敏响应能力的影响。结果表明,掺杂纳米管不仅提高了聚氨酯复合材料的力学和热学性能,更增强了其对有机溶剂饱和蒸汽的气敏响应能力;当固化温度为80℃时,聚氨酯复合材料的气敏响应能力最强。     

聚氨酯／碳纳米管复合材料的研究进展

近年来,利用碳纳米管制备聚氨酯复合材料引起人们的高度重视。本文对聚氨酯/碳纳米管复合材料的研究进展状况进行综述。概述了聚氨酯和碳纳米管的性质以及碳纳米管的改性处理方法;介绍了聚氨酯/碳纳米管复合材料的制备方法,包括物理共混法和原位聚合法;讨论了碳纳米管对复合材料力学性能、电学性能、光学性能以及其他性能的影响。结果表明,碳纳米管的加入使得复合材料在上述性能方面都有不同程度的改善。最后探讨了该研究领域存在的问题及今后可能的发展方向。     

碳纳米管/聚氨酯复合材料的粘接性能

利用超声分散、酸处理以及表面活性剂分散的方法将碳纳米管分散到蓖麻油中,制备了蓖麻油型聚氨酯/碳纳米管(PUR/CNTs)复合材料,观察了该复合材料的微观结构,探讨了CNTs用量、酸处理时间以及表面活性剂的用量对复合材料粘接性能的影响。结果表明,随着蓖麻油中CNTs用量的增加,该复合材料的粘接强度不断提高,当增加到2%时,粘接强度提高84.4%;硝酸处理3 h的聚氨酯/碳纳米管复合材料的粘接强度最大,比未酸处理的复合材料增加15%;表面活性剂分散的聚氨酯/碳纳米管复合材料的粘接强度能得到进一步的提高。     

喷雾干燥法制备聚氨酯/碳纳米管复合材料的结构与性能

通过喷雾干燥法制备了聚氨酯/碳纳米管复合材料。扫描电子显微镜和透射电子显微镜观察结果表明,碳纳米管在聚氨酯基体中分散较好。X-射线衍射测试表明,碳纳米管对复合材料的微相结构影响较小。随着碳纳米管用量的增加,动态力学性能测试表明复合材料的耐热性有了显著的改善。另外,该复合材料还表现出多功能特性,如高导电性和导热性。随着碳纳米管体积分数的增加,聚氨酯/碳纳米管复合材料的电导率逐渐提高,填充碳纳米管的聚氨酯复合材料的导电逾渗值约为5%。     

改性多壁碳纳米管／聚氨酯乳液的制备与研究

以聚醚多元醇（N-210）、异佛尔酮二异氰酸酯（IPDI）、二羟甲基丙酸（DMPA）、一缩二乙二醇（DEG）为基料,合成了水性聚氨酯预聚体,采用改性多壁碳纳米管（ MWCNTs ）的悬浊液为分散介质得到水性聚氨酯复合乳液。通过TEM、拉力机、TGA对其胶膜的微观结构、力学性能以及热学性能进行测试,结果表明： MWCNTs均匀分散在聚氨酯胶膜中;当MWCNTs质量分数在0.5％时,拉伸强度达到最大值为17.91 MPa,比纯聚氨酯提高了81％;复合材料的断裂伸长率均达到500％以上,最大达到539％,明显高于未加改性碳纳米管的聚氨酯; MWCNTs的加入可明显提高复合材料的耐热性。     

聚氨酯/碳纳米管复合材料的研究进展

综述了溶剂型聚氨酯/碳纳米管复合材料的制备方法,以及物理机械性能、电磁性能、生物相容性、耐热性和耐磨性等性能,简要介绍了水性聚氨酯/碳纳米管复合材料的制备及其性能,并提出了聚氨酯/碳纳米管复合材料的研究方向。     

酸化多壁碳纳米管/水性聚氨酯复合材料的制备与性能研究

采用混酸对多壁碳纳米管进行表面处理,通过共混法制备出酸化多壁碳纳米管/水性聚氨酯(WPU)复合材料。通过FT-IR,拉曼光谱,SEM表征了多壁碳纳米管酸化前后的结构,通过TGA、拉力测试以及SEM研究了复合材料的热性能、力学性能和微观结构。结果显示,多壁碳纳米管通过混酸处理后表面羧基化,管壁卷曲程度降低。与纯WPU相比,当添加量为1.5%时,复合材料的断裂伸长率增加29%,当添加量在2%时,复合材料的拉伸强度增加169%,酸化碳纳米管在聚氨酯(PU)基体中均匀分散。酸化碳纳米管的添加显著提高了复合材料的热稳定性和导电性。     

碳纳米管/聚合物复合材料的研究进展

综述了碳纳米管/聚合物复合材料的研究进展,介绍了碳纳米管/聚合物复合材料的制备方法,特别强调了碳纳米管在聚合物基体中的分散和排列;综述了碳纳米管/聚合物复合材料研究在力学、电学、热学、阻燃性能等方面所取得的进展,并详细讨论了碳纳米管的长径比、碳纳米管在聚合物基体中的分散效果及排列对碳纳米管/聚合物复合材料性能的影响;最后探讨了碳纳米管/聚合物复合材料进一步发展所面临的机遇和挑战.     

碳纳米管对酚醛树脂/碳纤维复合材料力学性能的影响

利用碳纳米管(CNTs)对酚醛树脂(PF)进行改性,研究了CNTs含量对PF/碳纤维(CF)复合材料力学性能的影响。研究表明,CNTs能够明显提高PF/CF复合材料的力学性能,当CNTs的含量为0.5%时,复合材料的弯曲强度达到最大值(891.8MPa),与未加入CNTs时相比提高了168.4MPa,而弯曲弹性模量降低了9.5GPa;当CNTs的含量为1.5%时,复合材料的压缩强度、层间剪切强度、冲击强度均达到最大值,与未加入CNTs时相比,分别提高了10.4%、79.2%、71.9%。     

聚氨酯/碳纳米管复合材料力学及电性能研究

利用超声分散和原位聚合的方法制备了聚氨酯／碳纳米管((PUR／CNTs)复合材料,观察了该复合材料的微观结构,探讨了CNTs含量对复合材料力学性能和电性能的影响。结果表明,CNTs在基体中获得了较好的分散,当CNTs质量分数为2％时复合材料的力学性能得到全面提高,与PUR相比,拉伸强度提高11．6％,拉伸弹性模量提高11．3％,断裂伸长率提高10．4％;复合材料的导电性能得到明显的提高,在CNTs质量分数为0．5％时可用作抗静电材料。     

Thermal conductivity improvement in electrically insulating silicone rubber composites by the construction of hybrid three-dimensional filler networks with boron nitride and carbon nanotubes

In this study, we constructed hybrid three-dimensional (3D) filler networks by simply incorporating a relatively low content of one-dimensional carbon nanotubes (CNTs; 0.0005–0.25 vol %) and a certain content of two-dimensional boron nitride (BN; 30 phr) in a silicone rubber (SIR) matrix. As indicated by transmission electron microscopy observation, flexible CNTs can serve as bridges to connect BN platelets in different layers to form hybrid 3D thermally conductive networks; this results in an increase in thermally conductive pathways, and the isolation between CNTs can prevent the formation of electrically conductive networks. Compared to the SIR–BN composite with the same BN content, the SIR–BN–CNT composites exhibited improved thermal conductivity, slightly increased volume resistivity, and comparable breakdown strength without a largely decreased flexibility. When 0.25 vol % CNTs were incorporated, the SIR–BN–CNT composite exhibited 75 and 25% higher thermal conductivities relative to the neat SIR and SIR–BN composite with 30 phr BN, respectively, and a thermal conductivity that was even comparable to SIR–BN composite with 40 phr BN. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46929.     

Thermal and ablative properties of binary carbon nanotube and nanodiamond reinforced carbon fibre epoxy matrix composites

The thermal and ablative properties of carbon nanotube (CNT) and nanodiamond (ND) reinforced carbon fibre epoxy matrix composites were investigated by simulating shear forces and high temperatures using oxyacetylene torch apparatus. Three types of composite specimens—(i) carbon fibre epoxy matrix composite (CF/Epoxy), (ii) carbon fibre epoxy matrix composite containing 0.1 wt-% CNTs and 0.1 wt-% NDs, and (iii) carbon fibre epoxy matrix composite containing 0.2 wt-% CNTs and 0.2 wt-% NDs—were explored. The ablative response of composites was studied through pre- and post-burnt SEM analysis and further related with thermogravimetric analysis, weight loss profile and thermal conductivity measurements. The novel nanofiller composites showed marked improvement in their thermal and ablative properties. A 22% and 30% increase in thermal conductivity was observed for composites containing 0.1 wt-% CNTs/0.1 wt-% NDs and 0.2 wt-% CNTs/0.2 wt-% NDs respectively. These nanofillers also improved the thermal stability of thermosetting epoxy matrix, and an increase of 13% and 20% was recorded in the erosion rate of composites containing 0.1 wt-% CNTs/0.1 wt-% NDs and 0.2 wt-% CNTs/0.2 wt-% NDs respectively. This improvement is due to the increased char yield produced by the increase in the loading of nanofillers, i.e. CNTs and NDs. Insulation index and insulation to density performance have also been improved due to increased thermal conductivity and char yield.     

碳纳米管复合物纳米流体切削液的稳定性与强化换热

将润滑剂硫化异丁烯（T321）填充到碳纳米管（CNTs）内以后制成复合物,再利用复合物制备了一种纳米流体切削液,研究了该纳米流体的分散稳定性、导热和黏度特性,分析了酸化处理时间、碳管微粒类型与浓度、表面活性剂、测试条件等对上述性能的影响。结果表明,T321填充CNTs时的填充率为25%左右,制备稳定分散纳米流体所需的两种表面活性剂十二烷基苯磺酸钠（SDBS）与吐温-80（TW-80）的最佳复配比例为3∶7,复配活性剂与碳管的最佳比例为5∶1。当CNTs的酸化处理时间为9h左右,且在充分、稳定分散的条件下,复合物可使基液的热导率提高110%,CNTs的形状因子对热导率的影响最为显著。所制备的纳米流体为一种非牛顿流体,当活性剂质量分数为0.5%左右时,其动力黏度最小。与普通CNTs所制备的纳米流体比,复合物纳米流体的热导率更高、黏度更小,这是由于在CNTs的开口与内部填充过程中,其表面被化学修饰,使复合物在基础液中具有更好的分散稳定性。     

碳纳米管改性双马来酰亚胺树脂体系的性能

采用原位聚合法将碳纳米管(CNTs)与双马来酰亚胺(BMI)复合制备BMI/CNTs复合材料,通过差示扫描量热仪分析了CNTs的用量对BMI树脂体系反应活性的影响。研究了CNTs的用量对复合材料静态力学性能、动态力学性能及耐湿热老化性能的影响。结果表明,随着CNTs用量的增多,体系的反应活性呈降低趋势,而力学性能、耐湿热性能均有所提高;当CNTs质量分数为1.5%时,复合材料的冲击强度和弯曲强度分别提高了近63.1%和10%,其后随CNTs用量的增大均略有下降。     

原位聚合制备碳纳米管/PMMA复合材料的研究

采用原位聚合的方法，制备了多壁碳纳米管／聚甲基丙烯酸甲酯复合材料。多壁碳纳米管经过强酸氧化处理。表面具有有机活性。碳纳米管的加入并未使聚合诱导期延长，但令体系粘度增加，自加速现象提早出现。DMA和TGA的研究表明，碳纳米管用量少于1．0％的复合物玻璃化温度降低，分解温度无显著变化。加入1．0％的碳纳米管可以使PMMA复合材料冲击强度提高80％以上。断面扫描电镜表明，碳纳米管呈单管分散于基体中。     

Catalytic combustion synthesis of CNTs/MgO composite powders and the influences on the thermal shock resistance of low-carbon Al2O3–C refractories

Using MgC₂O₄, Mg powders as raw materials and Ni(NO₃)₂?6H₂O as a catalyst, CNTs/MgO composite powders were prepared by a catalytic combustion synthesis method. The CNTs/MgO composite powders were characterized by XRD, Raman spectroscopy, FESEM/EDS and HRTEM. The effects of catalyst content on the degree of graphitization and aspect ratio of the CNTs in composite powders were investigated. Moreover, the thermal shock resistance of low-carbon Al₂O₃–C refractories after adding the composite powder was investigated. The results indicated that the CNTs prepared with 1 wt% Ni(NO₃)₂?6H₂O addition had a higher degree of graphitization and aspect ratio. In particular, the aspect ratio could reach approximately 200. The growth mechanism of hollow bamboo-like CNTs in the composite powders was proven to be a V-L-S mechanism. The thermal shock resistance of Al₂O₃–C samples could be improved significantly after adding CNTs/MgO composite powders. In particular, compared with CM0, the residual strength ratio of Al₂O₃–C samples with added 2.5 wt% composite powders could be increased 63.9%.     

碳纳米管分散强化PVDF复合薄膜导热性能探究

采用多巴胺（DA）和3?氨基丙基?三甲氧基硅烷（APTMS）对碳纳米管（CNTs）进行DA辅助共修饰,并用溶剂浇铸法制备具有优异热性能和力学性能的聚偏氟乙烯（PVDF）复合薄膜;采用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、差示扫描量热仪（DSC）、X射线光电子能谱仪（XPS）、热常数分析仪和电子单纱强力仪等对材料的微观形貌、结晶度、导热性能和力学性能进行了表征。结果表明,经DA和APTMS共修饰后的PDA?CNTs?NH₂具有良好的分散性能;PDA?CNTs?NH₂的加入,有利于改善PVDF复合薄膜的热稳定性;与纯PVDF薄膜和PVDF/CNTs复合薄膜相比,PVDF/PDA?CNTs?NH₂复合薄膜的导热性能和力学性能显著增强,在8 %（质量分数,下同） PDA?CNTs?NH₂的填料负载下,其热导率达到0.337 9 W/（m·K）,是纯PVDF薄膜的1.78倍,其拉伸强度为52.67 MPa,是纯PVDF复合薄膜的1.36倍。     

Structure and properties of polypropylene‐wrapped carbon nanotubes composite

By means of in situ graft method, polypropylene (PP)‐wrapped carbon nanotubes (CNTs) composite were prepared. Infrared spectroscopy (IR) results showed that there was covalent linkage between PP and CNTs via maleic anhydride (MAH) grafting. Owing to the uniform dispersion of CNTs and covalent adhesion between PP and CNTs, the tensile strength of PP‐wrapped CNTs composite was higher than that for neat PP by 110%, and a 74% increase as compared to the CNTs/PP (with the same CNTs content) composite. The further test showed a strong mechanical behavior with up to 113% increase in Young's modulus of the neat PP. Based on the uniform dispersion of CNTs, the electrical conductivity of PP‐wrapped CNTs composite increased sharply by up to seven orders of magnitude with 4 wt % CNT fillers. As a result, the volume resistivity was decreased with increase in the CNT content that could be governed in a percolation‐like power law with a relatively low percolation threshold. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009