Preparation And Properties Of Bioinspired Thermal Conductive Composites

Polymeric materials have found an important application in chemical engineering,petroleum,pharmacy,electronic computer and national defence industry due to their superior advantages such as corrosion resistance,scaling resistance,low density,facile processing and cheap price.Most of polymeric materials have low thermal conductivity,which limit their wide application.In this work,a series of thermal conductive composites guided by bionics were fabricated and their thermal conductivity and mechanical strength were studied.Thermal enhancement mechanism was elucidated by mathematical model.The heat exchange experiments were conducted to explore the potential application of composite material in the field of chemical heat exchange.The main content and research conclusion are shown as follows:?.Inspired by the alignment structure of spider silk protein,the magnetic carbon nanotube was prepared by electrostatic layer-by-layer adsorption,and aligned magnetic carbon nanotube-poly(vinylidene fluoride)(PVDF)composite was fabricated by mechanical field oriented method.The thermal conductivity of composite was significantly improved when the carbon nanotube aligned along the heat flow.The thermal conductivity of vertically aligned carbon nanotube-PVDF composite is 0.506 W/m·K at the loading of 15wt%.The composite heat exchanger has potential application in high salinity medium because of their advantages such as scaling resistance,corrosion resistance and high stability.?.Inspired by the adhesion ability and metal cation chelating ability of dopamine,the dopamine and magnetic co-functionalization of boron nitride was applied to enhance the thermal conductivity of co-modified boron nitride-PVDF composite.The thermal conductivity increases with the filler loading.The thermal conductivity of co-modified boron nitride-PVDF composite is 1.430 W/m·K at the loading of 20wt%.The dopamine and magnetic co-functionalization of boron nitride can enhance phonon conduction efficiency and promote the construction efficiency of thermal conduction channels,which leads to reduce the thermal resistance and increase the thermal conductivity of materials.The composite heat exchanger exhibits excellent heat transfer ability and corrosion resistance in strong alkali medium,which can provide new ideas for the design of new material heat exchanger.?.Inspired by the spine structure of sea urchin,graphite-coated ferric oxide microsphere similar to sea urchin structure was prepared by hydrothermalcarbonization method.The graphite-coated ferric oxide microsphere-PVDF composite was fabricated by solvent evaporation method.The sea urchin structure of fillers is helpful for the dispersion of fillers and can effectively improve the thermal conductivity of materials.The thermal conductivity of the composite is 27.2% higher than that of pure PVDF at the loading of 5 wt%.The sea urchin filler can improve the efficiency of building thermal conductivity channel,leading to the enhancement of thermal conductivity.The graphite-coated ferric oxide microsphere are uniformly dispersed in the composite material,and take the mechanical external force together without concentrating the external force at one point.Therefore,the tensile strength of composite material keeps constant after incorporating of filler.