| With the rapid development of electronic integration technology,electronic components and electronic equipment are quickly developing in the direction of smallness,lightness and thinness.However,as the operating frequency constantly increase,the electronic device will inevitably produce a large amount of heat because of electrical power loss,which leads to the invalidation of electronic components that is sensitive to temperature.Therefore,it is necessary and urgent to develop high thermal conductive material,Due to easy processing,excellent physical and chemical performance,polymer matrix composites with high thermal conductivity has won the people 's widespread attention and are widely used in the spacecraft,electronics,automobile and electrical machine.In this paper,the superfullerenes?SF?,carbon nanotubes?CNT?,graphene nanosheets?GS?and MXene?Ti3C2Tx?are used as nano thermal conductive filler,poly?vinylidene fluoride??PVDF?used as the matrix,respectively,we successifully prepared PVDF/SF,PVDF/CNT,PVDF/GS and PV DF/MXene composites,respectively and tried to focus on exploring two aspects as the following.?1?By means of solution blending and hot pressing,the same loading of three kinds of nano carbon materials including superfullerenes,carbon nanotubes,graphene nanosheets are put into the PVDF matrix and three kinds of different PVDF composites were successfully fabricated.And then we systematically studied the effect of three different dimensional carbon materials on the thermal and mechanical properties of PVDF.The results indicated that: 1)the addition of three kinds of carbon materials is indeed conducive to enhance the thermal conductivity of PVDF matrix,but the enhance ment varies from different dimension.Compared with the neat PVDF,when the loading of filler is 20 wt%,the thermal conductivity of PVDF/SF,PVDF/CNT and PVDF/GS are 0.194,0.604 and 2.06 W/mK,respectively,corresponding to 2.6%,220%,1000% increasement.It indicated that the two dimensional GS has a great advantage over one-dimensional CNT or zero dimensional SF in improving thermal conductivity 2)PVDF/SF,PVDF/CNT and PVDF/GS composited exhibit a good thermal stability,especially for the GS which increases the thermal decomposition temperature of PVDF up to 14°C.3)dynamic thermo-mechanical properties of the PVDF composites is better than neat PVDF,expecially when the test temperature is set at 80°C,the storage modulus of PVDF/SF,PVDF/CNT,PVDF/GS composites are 5.6,6.2,8.1 GPa,respectively,which increased by 60%,77.1%,131% compared with the neat PVDF.?2?Ti3AlC2 three titanium carbon compound used as matrix material,hydrofluoric acid?HF?was firstly used for etching,and then intercalated with N-N dimethyl formamide?DMF?and ultrasonic is simultaneously proceeding,which results in the formation of little-layer even single MXene.Finally the as-preparard MXene nanosheets were added to the PVDF matrix and PVDF/MXenes composites were prepared.We made use of Laserflash thermal analyzer?LFA 447?,dynamic thermal mechanical analyzer?DMA?to study thermal conductivity,thermal stability,dynamic thermo-mechanical properties of PVDF composite with different loading of MXene and the results demonstrated that: 1)using hydrofluoric acid?HF?to etch aluminum titanium carbide?Ti3 AlC2?can lead to the ocurrence of MXene nanosheets after ultrasonication.2)the addition of MXene nanosheets can enhance thermal conductivity of PVDF and when the loading of filler is 1 wt%,2 wt%,3 wt%,4 wt%,5 wt%,the thermal conductivity of PVDF/MXene composite are 0.183,0.233,0.265,0.306 and 0.363 W/mK,respectively,which increased by 4%,33%,51%,75% and 107% compared to neat PVDF.3)the thermo-mechanical properties of PVDF/MXene composites showed an good improvement because of the addition of MXene nanosheets,especially when the content of MXene is 5 wt%,storage modulus of PVDF/MXene composite material attained as high as 7.5 GPa and the glass transition temperature rised to 25.5°C,increasing by 64% and 6.5 °C,respectively,compared to neat PVDF. |
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