热压制备改性石墨烯-水泥基复合材料:改善微观结构、导热性能和力学性能

Preparing Modified-graphene-reinforced Cement-based Composite Material by Hot-pressing Process for Microstructure,Thermal Conductivity and Mechanical Properties Amelioration

采用热压成型工艺制备了石墨烯-水泥基复合材料,研究了硅烷偶联剂和行星球磨时间对复合材料性能的影响。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、傅里叶变化红外光谱(FTIR)和氮吸附比表面积测定仪等对复合材料进行了微观分析。结果显示:当偶联剂和石墨烯掺量为1%时,复合材料导热系数和抗压强度分别达到3.132 3 W/(m·K)和54.9 MPa,相较于未使用偶联剂处理的样品,分别提高了42.07%和28.87%;球磨能提高石墨烯在复合材料中的分散性,当球磨时间为0.5h、石墨烯掺量为1.5%、偶联剂含量为1%时,复合材料导热系数和抗压强度分别为3.687 2W/(m·K)和57.4MPa;微观形貌和孔结构分析表明,采用热压成型工艺制备的复合材料孔隙率更低,结构更为致密。

Using silane coupling-agent-modified graphene,a series of graphene-reinforced cement-based composites（differing in coupling agent content and ball milling duration）were prepared by a hot-pressing process and the resultant composites＇ performances were examined.X-ray diffraction（XRD）,scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FTIR）and N2 absorption BET surface area analyser were employed to study microstructure of the composite.The results showed that the combination of a 1% dosage of coupling agent and a 1% dosage graphene can achieve a thermal conductivity and a compressive strength of 3.132 3 W/（m·K）and 54.9 MPa（42.07% and 28.87% higher than the composite without coupling agent modification）,respectively;the ball milling can improve the dispersibility of graphene in composite,and when the milling time,graphene dosage and coupling agent dosage are 0.5 h,1.5%,1%respectively,a reinforced cement-based composite with a thermal conductivity of 3.687 2 W/（m·K）and a compressive strength of 57.4 MPa can be obtained.The microstructure and pore structure analysis showed that the composite prepared by hot-pressing process has lower porosity and more dense structure than the blank sample.