دانلود رایگان مقاله لاتین تقویت خواص حرارتی مواد پلیمر از سایت الزویر
عنوان فارسی مقاله:
اثر هم افزایی BN و گرافن نانوصفحات در چارچوب سه بعدی بر تقویت خواص حرارتی مواد پلیمری مرکب
عنوان انگلیسی مقاله:
Synergistic effect of BN and graphene nanosheets in 3D framework on the enhancement of thermal conductive properties of polymeric composites
سال انتشار : 2016
برای دانلود رایگان مقاله تقویت خواص حرارتی مواد پلیمر اینجا کلیک نمایید.
مقدمه انگلیسی مقاله:
1. Introduction
Thermal conductive polymeric composites have attracted much attention because of their broad applications in electronic, hightemperature dielectric and energy storage devices [1,2]. Quite a few of methods were carried out to obtain the composites with high thermal conductive properties [3]. Careful revision can be found that the most fundamental strategy embodied in these methods is to construct unobstructed thermal conductive paths in the polymer matrix. For example, a common method to enhance a polymer's thermal conductivity (TC) is to blend it with high-TC fillers such as metal or ceramic particles [4]. With the increasing of the amount of filler, the thermal conductivity of composites increased slowly until the filler fraction reached a percolation threshold where a rapid increase in conductivity started. Fillers had to form a random close-packed structure to maximize a pathway or network for heat conduction through the polymer matrix. However, the large amount of fillers required to exceed the percolation threshold can not only deteriorate the superior performance of polymer matrix such as electrical and optical properties, but may also significantly increase the material cost [5]. Therefore, it is a challenge and a hot topic to improve their thermal conductive ef- ficiency or reduce the amount of fillers [6]. Layered inorganic nanomaterials, such as graphene and BNNSs, were proved to be a good choice to set up a thermal conductive path due to their high TC and large aspect ratio [7e9]. For example, Yu et al. [10] regulated aspect ratio of the graphite nanoplatelets (GNP, ~5 vol%) from 3 to 200 and finally obtained the epoxy nanocomposites with the TC up to 1.45 W$m1 $K1 . A recent work by Ganguli et al. [11] revealed that a 55% (0.30 W$m1 $K1 ) increase of TC had been reached in the composite with a 2 wt% silanetreated GNPs dispersed in epoxy matrix. While the TC further enhanced by 28-fold (5.8 W$m1 $K1 ) when the GNPs loading was up to 20 wt%. In this case, the aforementioned problems still exist, especially that when the filler content is high, it is very difficult to uniformly disperse these layered fillers in polymer composites [12,13]. Though the filler's aggregation could be avoided to a certain degree by surface modification, the excessive modification would destroy the lamellar structure and thus reduce the effects of the fillers on TC enhancement [14e17]. So recently, the combined use of hybrid fillers was proposed as one solution for improve the thermalconductive efficiency in polymer composites [18e21]. Yu et al. [22] reported that the TC of the grease composites containing 63 vol % alumina was 2.7 W$m1 $K1 ; and the TC enhanced by 28% (to 3.45 W$m1 $K1 ) after further compounded with 1 wt% graphene. Another work by Tsai et al. [23] blended functionalized BN and glycidy-methacrylate-grafted graphene with polyimide (PI) to fabricate a thermal conductive PI composites. TC increased from 0.13 W$m1 $K1 of neat PI to 2.21 W$m1 $K1 of thermal conductive PI composites. Our group also studied the effect of the BN and graphene hybrid fillers on the TC improvement in polymeric composites and proposed a morphology-promoted synergistic effect between graphene and BN nanolayers [18]. In the present work, we further demonstrated a synergistic effect of BN nanosheets (BNNSs) with graphene in a 3D framework on the enhancement of thermal conductive of PA6 composites. The 3D BN/graphene framework (BGF) was obtained by assemble BNNSs and graphene oxide (GO) with the hydrothermal reduction and freeze-drying process. PA6/BGF (PBGF) composites were prepared by the in-situ “grafting to” strategy, in which the PA6 chains were covalently grafted on the 3D framework. The TC of PA6 composites with BGF (1.6 wt% BNNS/6.8 wt% graphene) was improved to 0.891 W$m1 $K1 . This value indicated that additional introduction of 1.6 wt% BNNSs could increase the TC up to 87.6% and 350% compared with the composites containing 6.8 wt% 3D graphene (0.475 W$m1 $K1 ) and neat PA6 (0.196 W$m1 $K1 ), respectively. As far as we know, the synergistic effect of BNNSs and graphene in a hybrid 3D framework has not been observed previously. The obtained polymeric materials could be applied in thermal interface materials, polymer dielectrics, and other high-performance thermal management system [1].
برای دانلود رایگان مقاله تقویت خواص حرارتی مواد پلیمر اینجا کلیک نمایید.
کلمات کلیدی:
Heat transport enhancement of heat sinks using Cu-coated graphene ... www.sciencedirect.com/science/article/pii/S0254058417303723 May 21, 2017 - Thermally conductive graphene nanosheets (GNs) decorated with Cu ... but also as fillers, forming stereo conductive framework for thermal transport and .... Thermal properties and electrical characterization of Cu/GN films. Enhancement of Thermal Conductivity of Phase Change Materials by ... repository.ust.hk/ir/Record/1783.1-83124 by Y Ji - 2016 - Related articles Enhancement of Thermal Conductivity of Phase Change Materials by 3D ... are used as effective three dimension (3D) interconnected framework of paraffin phase change materials to increase thermal conductive and high electrical resistance. [PDF]Significant thermal conductivity enhancement for nanofluids ... web.me.iastate.edu/wang/2011_PLA.pdf by W Yu - 2011 - Cited by 143 - Related articles Jan 22, 2011 - for the lattice thermal conductivity of graphene in the framework of Klemens ... thermal transport properties of graphene-based nanofluids, and. Strong Enhancement of Thermal Properties of ... - at www.arxiv.org. https://arxiv.org/pdf/1311.6029 by P Goli - 2013 - Cited by 2 - Related articles increases the thermal conductivity of 9-μm (25-μm) thick Cu films by up to 24% (16 ... Enhancement of thermal properties of metal films via graphene coating may. In situ formation of a cellular graphene framework in ... - RSC Publishing pubs.rsc.org/en/content/articlepdf/2017/TA/C7TA00750G Mar 2, 2017 - to its excellent thermal, mechanical, and electrical properties, ... done for investigating the thermal conductivity enhancement. (TCE) of ... In situ formation of a cellular graphene framework in ... - RSC Publishing pubs.rsc.org/En/content/articlehtml/2017/ta/c7ta00750g Mar 2, 2017 - Owing to its excellent thermal, mechanical, and electrical properties, ... the thermal conductivity enhancement (TCE) of graphene/polyolefin ... [PDF]Enhancement of thermal conductivity of phase change materials by 3D ... ir.siat.ac.cn:8080/bitstream/172644/10114/1/集成-先进材料2016039.pdf dimension (3D) interconnected framework of paraffin phase change materials to increase thermal conductive and high electrical resistance. The GF@Al2O3.
