还原纳米石墨/聚氨酯导电胶的制备与性能研究

利用异氰酸酯与多元醇在不同的反应条件下制取三种性能不同的聚氨酯(PU)预聚体(PUⅠ、PUⅡ和PUⅢ),然后分别与还原纳米石墨(RNG)、三羟甲基丙烷(TMP)混合制备三种RNG/PU导电胶(RNG/PUⅠ、RNG/PUⅡ和RNG/PUⅢ)。运用多种检测手段对导电胶的导电性能、力学性能和热稳定性能进行了分析。结果表明:随着RNG质量分数的增加,三种导电胶的导电性能均增强,其导电逾渗阀值分别为10.0%、16.7%和20.0%;导电胶的拉伸剪切强度随RNG质量分数的增加呈先升后降的趋势,当w(RNG)=20%时导电胶的拉伸剪切强度为1.37～4.40MPa;RNG的加入使导电胶的热稳定性能明显提高。     

还原纳米石墨/聚氨酯导电胶的制备与性能研究

利用异氰酸酯与多元醇在不同的反应条件下制取三种性能不同的聚氨酯（PU）预聚体（PUⅠ、PUⅡ和PUⅢ）,然后分别与还原纳米石墨（RNG）、三羟甲基丙烷（TMP）混合制备三种RNG/PU导电胶（RNG/PUⅠ、RNG/PUⅡ和RNG/PUⅢ）。运用多种检测手段对导电胶的导电性能、力学性能和热稳定性能进行了分析。结果表明：随着RNG质量分数的增加,三种导电胶的导电性能均增强,其导电逾渗阀值分别为10.0%、16.7%和20.0%;导电胶的拉伸剪切强度随RNG质量分数的增加呈先升后降的趋势,当w（RNG）=20%时导电胶的拉伸剪切强度为1.37～4.40MPa;RNG的加入使导电胶的热稳定性能明显提高。     

石墨/环氧树脂导电胶的研究

研究了以石墨、环氧树脂、三乙醇胺及其它添加剂组成的导电胶体系。分别以鳞片石墨、还原石墨、鳞片石墨/铝粉作导电介质制备石墨导电胶。通过多种分析手段对三种石墨导电胶的导电性能、力学性能和热学性能等进行了考察三种石墨导电胶的性能参数为:当w(石墨)=35份时,鳞片石墨导电胶鳞片石墨/铝粉导电胶和还原石墨导电胶的体积电阻率分别为0.05690.48830.2794Ω·cm,剪切强度分别为6.211.19.3MPa,热失重速率分别为-8.7-4.7-7%/min[当w(石墨)=30份、升温速率为8℃/min时]。石墨导电胶具有良好的工业应用前景。     

镀银纳米石墨微片/丙烯酸酯导电压敏胶的研究

以天然EG(膨胀石墨)为原料,采用超声分散法制得NanoG(纳米石墨微片);然后采用化学镀法制备导电填料Ag-NanoG(镀银纳米石墨微片);最后采用溶液共混法制备丙烯酸酯类Ag-NanoG/PSA(镀银纳米石墨微片/导电压敏胶)。研究结果表明:NanoG表面镀上了一层均匀紧凑的金属Ag,Ag层厚度为250 nm左右,其质量分数为50.04%;导电填料Ag-NanoG已均匀分散在丙烯酸酯PSA基体中,并形成了导电网络;当w(Ag-NanoG)=40%时,Ag-NanoG/PSA的综合性能相对最好,其180°剥离强度为0.25 kN/m,剪切强度为0.133 MPa且电导率为2.5×10-2S/cm。     

复合导电填料导电胶的研究(英文)

在铜粉表面进行化学镀银,获得银铜导电粉。把镀银铜粉与1%的TiFeCoNi纳米合金粉混合,制成复合导电填料。用环氧树脂、复合导电填料和固化剂混合制成导电胶粘剂。对导电胶的性能进行了测试。结果表明,当导电填料占导电胶重量比的70%时,导电率可达0.005Ω·cm。最佳的固化条件是130℃、保温3 h。把导电胶放在85℃条件下保温600 h,导电胶的电阻率和剪切强度变化量不超过20%。导电胶的电阻随使用温度的变化类似于金属电阻的变化规律。     

镀银石墨/有机硅导电胶的耐热性能研究

以镀银石墨粉作为导电填料,环氧树脂(EP)改性有机硅树脂作为基料,制备镀银石墨/有机硅导电胶,并对导电胶的高温导电性能、耐热老化性能和热稳定性能进行了分析。研究结果表明:当老化时间为160 h、老化温度≤180℃时,导电胶的体积电阻率变化不大,剪切强度仍相对较高,说明导电胶可在此温度范围内较长时间使用。     

还原石墨导电胶的研究

采用水合肼(85%)对膨胀石墨进行还原改性,制得导电性能良好的还原石墨。以还原石墨、环氧树脂(EP)、三乙醇胺及活性添加剂(自制)复合制备还原石墨导电胶系列。通过傅里叶红外(FT-IR)分析确定了该还原石墨导电胶系列的适宜固化条件,运用多种检测手段对导电胶的导电性能、力学性能和热学性能等进行分析,利用X-射线能谱仪对还原石墨的表面含氧量进行考察。研究结果表明,该还原石墨导电胶系列的适宜固化条件为120℃×180 min,体积电阻率为0.3439～1.4877Ω·cm,拉伸剪切强度为12.3～19.7 MPa;该导电胶可在不超过300℃的环境下使用,具有巨大的市场潜力和广阔的工业应用前景。     

镀银铜粉导电胶制备及表征

为了制备高抗氧化性能铜粉,采用AgNO_3为银源,化学镀法制备了不同含银量的超细镀银铜粉。将镀银铜粉作为导电填料制备导电胶,系统研究了制备工艺对导电胶性能的影响。结合扫描电镜(SEM)、X射线衍射(XRD)、X射线荧光(XRF)、流变仪测试、四探针电阻率测试、万能电子拉力机、热分析(DSC/TG)等分析手段,研究了镀银铜粉的形貌、晶体结构、导电胶黏度、电性能、强剪切度和固化过程热性能。结果表明:镀银铜粉具有较好的导电性及抗氧化性能。推荐最佳的导电胶制备工艺为:65%镀银铜粉、35%的环氧树脂,在150℃下固化10 min,该导电胶制备出薄膜的电阻率为8.73×10~(-4)?×cm,焊接铜片剪切强度为11 MPa,,具有优异的抗老化性能。     

丁腈橡胶/膨胀石墨导电纳米复合材料的制备和性能

采用熔融插层法制备了丁腈橡胶/膨胀石墨纳米复合材料。扫描电镜(SEM)研究表明,超声处理后的膨胀石墨薄片厚度为纳米级。透射电镜(TEM)研究证实,膨胀石墨确以纳米级尺寸分散在橡胶基体中。力学性能研究表明,填加5份膨胀石墨时,纳米复合材料的拉伸强度最大,为28·4MPa,是不含膨胀石墨的复合材料的1·8倍。导电性能研究显示,填加10份膨胀石墨时,纳米复合材料的表面电导率和体积电导率分别为1·1×10-9S/cm和1·2×10-9S/cm,是不含膨胀石墨的复合材料的100倍和43倍。     

铜粉添加型导电胶的研制

以环氧树脂E-51为导电胶基体树脂、二乙烯三胺为固化剂,采用硅烷偶联剂(KH-550)对铜粉进行改性处理,并以此作为导电填料,制备了热固化各向同性导电胶。通过正交实验探讨了固化剂、硅烷偶联剂、还原剂、稀释剂和导电填料等因素对导电胶固化性能、粘接性能和导电性能的影响,并对导电胶的制备参数进行优化,得到了制备导电胶的最佳方案。实验结果表明,所制备的热固化各向同性导电胶具有制备工艺简单、粘接强度高(剪切强度≥20 MPa)和导电性能好(体积电阻率为1.50×10-3Ω·cm)等特点;经室温1000h老化实验后,导电胶的体积电阻率和剪切强度变化率<20%。     

Preparation and adhesive performance of electrical conductive epoxy-acrylate resin containing silver-plated graphene

The epoxy-acrylate (EA) was mixed with Ag-plated graphene (Ag-G), which was used as the conductive filler, to prepare the dual-curable electrical conductive adhesive (ECA). The characterization of Ag-G has been carried out by transmission electron microscope, X-ray diffraction, Raman spectrum, and X-ray photoelectron spectroscopy. Results showed that the Ag-G has been successfully prepared and the relative amount of Ag nanoparticles was 11.25?At%. The mechanical and conductive properties together with thermal stability of ECA have also been investigated. The shear strength reached to 4.67?MPa and the electrical conductivity of ECA reached to 0.41?S/cm when the content of conductive filler was 25?wt%, respectively. This content was regarded as the optimum. And, thermal analysis indicated that ECA exhibited better thermal stability than EA.     

On the Use of Silver Plated Nano Aluminum Nitride and Silver Plated Chopped Carbon Fiber to Prepare Electrically Conductive Adhesives with High Thermal Conductivity

To satisfy the high electrical and thermal conductivity required for the development of microelectronic products, silver plated aluminum nitride (Ag/AlN) and silver plated chopped carbon fiber (Ag/CF) were added into an acrylate resin to prepare electrically conductive adhesives (ECAs) with high thermal conductivity. The Ag/AlN was prepared by subjecting AlN to an electroless silver plating using a Pb-free activation method. The Ag/AlN has good electrical and thermal conductivity compared to the AlN without treatment. When the weight fraction of Ag/AlN is 45 ωt%, the electrical conductivity of ECAs based on acrylate resin filled with Ag/AlN is 1.5 S/cm, and the thermal conductivity reaches 2.1 W/(m · K). With the addition of 3 ωt% Ag/CF as supplement filler, the electrical conductivity has a sharp increase to 17.8 S/cm because of the formation of conductive networks in the ECAs. However, the shear strength has an apparent loss, falling from 4.2 to 1.1 MPa.     

Properties of Phenolic-Based Ag-Filled Conductive Adhesive Affected by Different Coupling Agents

In this study, a phenolic-based Ag flake-filled electrically conductive adhesive (ECA) was investigated in terms of rheological, electrical, and mechanical properties. To clarify the effect of various Ag flake filler content and silane coupling agents on the characteristic of the ECA, rheological properties of the Ag flake-filled ECA paste, electrical resistivity, and shear strength of the cured ECA were investigated. Results showed that an increase of Ag flake content leads to an increase in both viscosity of the ECA paste and electrical conductivity of the as-cured ECA. Silane coupling agents-treated Ag flakes have a significant effect on the electrical resistivity and shear strength in the ECAs.     

复合填料/聚丙烯酸酯导电压敏胶的制备与性能

针对导电胶黏剂（ECA）在实用中所遇到填料组分单一、易团聚、对基体力学性能影响较大等问题,本文利用不同组分填料间的架桥、插层等“协同”效应,将一定比例的碳黑（CB）、碳纤维（CF）、碳纳米管（CNTs）、纳米石墨微片（NanoG）复合作为导电填料加入到聚丙烯酸酯压敏胶（PSA）中,采用溶液共混法超声分散,得到填料添加量小、导电性能和力学性能良好的导电PSA。运用多种检测手段对导电PSA的电学性质、微观结构、热稳定性和力学性能进行了分析。结果表明,复合填料组成为CF 3%、NanoG 5%、CNTs 5%（均为质量分数）时,导电PSA的电导率达到3.0×10?2S/cm,180°剥离强度为0.38kN/m。     

环保型耐高温集成电路封装用导电银胶的研究

采用E-51型环氧树脂做基体,甲基纳迪克酸酐做固化剂,1~3μm片状银粉做导电填料,2-乙基-4甲基咪唑做促进剂,按照一定的质量配比,采用混合工艺制备出了一款电学性能、力学性能、耐高温性能都很好的绿色环保型导电银胶。经过性能测试,该产品的体积电阻率为72 mΩ·m,剪切强度为16.1 MPa,满足集成电路封装使用。     

双氰胺固化型导电胶性能优化及作用机理研究

针对双氰胺固化型环氧导电胶体积电阻率大等缺点,调查了不同结构短链有机二元酸对其导电性能的改善效果。发现在所调查的五种短链二元酸中,己二酸不仅可以改善导电胶的导电性能,同时能提高导电胶的力学性能。采用己二酸对银粉进行表面处理,通过热重、XPS、DSC等分析测试发现,己二酸不仅可有效去除银粉表面硬脂酸,同时其中一个羧酸官能团在银粉表面形成己二酸盐,其另一官能团在导电胶加热固化过程中参与固化反应,进而在银粉与环氧树脂之间形成偶联,从而提高导电胶的导电和力学性能。     

异氰脲酸酯基团对聚氨酯弹性体性能影响研究

引入异氰脲酸酯基团可提高聚氨酯弹性体的耐热性能,但同时对其他性能有一定影响。通过改变NCO含量考察异氰脲酸酯基团对聚氨酯弹性体的力学性能及耐溶剂性能的影响。力学性能测试结果表明,其硬度、拉伸强度和撕裂强度均在NCO质量分数为8％时达到极大值,分别为邵A60、10．33MPa和48．84kN／m,扯断伸长率随NCO含量增加单调减小,100％定伸强度单侧增大;耐溶剂实验表明,聚氨酯弹性体在NCO质最分数为8％时耐溶剂性能最好。     

Properties investigation on electrically conductive adhesives based on acrylate resin filled with silver microsheets and silver plating carbon fibers

The introduction of highly electrically conductive fillers (Ag microsheets and silver plating carbon fiber) can functionally improve the electrical conductivity of acrylate resin. In this study, Ag microsheets and Ag/CF were thus introduced into acrylate polymer via solution blending method under ultrasonication in order to improve the electrical conductivity of the acrylate resin. The properties and microstructures of Ag microsheets, CF, Ag/CF and ECAs were performed by scan electron microscope (SEM), X-ray diffraction analysis (XRD), etc. SEM images and XRD results illustrated that the impurities in carbon fiber could be completely removed after the adequately alkali treatment. The SEM images showed that large numbers of metallic silver particles were uniformly and densely coated on the surface of the carbon fibers and hybrid fillers (silver microsheets and Ag/CF) could homogeneously disperse in acrylate resin. Electrical conductivity measurements demonstrated that the electrical conductivity of ECAs increased with the increasing content of hybrid fillers and the percolation threshold of ECAs was 5 wt%. The electrical conductivity of ECAs at its percolation threshold was 15.79 S/cm, which was two orders of magnitude higher than that of the ECAs based on acrylate resin filled with silver microsheets. The increment in Ag/CF contents may decrease 180° peel strength and raise shear strength with low content of Ag/CF. The overall performance of ECAs was optimum with 2 wt% Ag/CF. The TGA analysis indicated that ECAs possess excellent thermal stability.