Preparation And Properties Of High Thermal Conductivity Polyether Ether Ketone Composites

Thermally conductive polymer materials are particularly outstanding in impact resistance,toughness,light weight and excellent processability.They are widely used in microelectronics,LED lighting,automotive industry,and aerospace industry.In particular,it has far-reaching influence on the development of microelectronic packaging and LED lighting technology,and plays an important role in the field of irreplaceable other materials.At the same time,the application range of thermal conductive polymer materials is continuously infiltrating into the fields of use of conventional heat conductive materials and thermally conductive inorganic materials.At present,the research and industrial application of thermal conductive polymer materials have made great progress both at home and abroad,and a large number of related reports have emerged every year.However,the current research on thermal conductive polymers is not perfect.It is far from the development of industrial needs and applications and this has seriously affected and restricted its extensive industrial application.Therefore,in order to impart good thermal conductivity to the thermal insulation polymer material,it is urgent to strengthen the research on the thermal conductive polymer material.As a special engineering material,polyaryletherketone(PAEK)has excellent processing properties,thermal properties and mechanical properties.Polyether ether ketone(PEEK)is one of the most widely used engineering plastics,and it has great value in aerospace,military defense and electronic packaging.The specific functional polyetheretherketone special engineering plastics have shown great potential application value in many high-end technology fields,and thermal conductivity polyetheretherketone is one of them.Almost all polyaryletherketone materials have thermal conductivity in the range of 0.2-0.3 W/(m·K),and pure polyetheretherketone has a thermal conductivity of only 0.3 W/(m·K)at room temperature.Undoubtedly affects and restricts the application and development of special engineering plastics in microelectronics,LED and other fields.The conventional structure of the thermally conductive polymer material improves the thermal conductivity of the material by introducing particles or inorganic fillers having high thermal conductivity,but the degree of improvement is limited.In order to greatly improve the thermal conductivity of polymer materials,it is necessary to build a thermal network in the matrix,which often requires sacrificing the mechanical properties of the material itself,and filling a large amount of thermally conductive filler.In this paper,high thermal conductivity,low filling amount,and no sacrifice of the mechanical properties of the material are taken as the starting point.The experiment is designed in two forms,aiming to prepare polyetheretherketone with high thermal conductivity under the condition of low mass fraction thermal conductive filler.Composite material.First,a sulfonated polyetheretherketone(SPEEK)having a low sulfonation degree was designed and synthesized by a "sulfonation method" using a sulfonated monomer.All the composite materials prepared in the experiment were made of PEEK and SPEEK as the matrix,and carbon fiber as the heat conductive filler,and kept at 30 wt.% mass fraction.The design uses double percolation behavior to change the distribution of carbon fiber in the matrix.By controlling the ratio of PEEK to SPEEK in the matrix,a series of polyetheretherketone composites with different matrices were prepared and characterized by structural characterization and performance.The results show that for the two-phase matrix,the carbon fibers are mainly distributed at the two-phase interface.In the interfacial region,the result is that the local concentration of carbon fibers is greater than the average concentration of the overall composite.The low-mass fraction carbon fiber undergoes percolation behavior,which forms a heat conduction path and a heat conduction network in the composite material,and effectively improves the thermal conductivity of the polyetheretherketone composite material.A polyetheretherketone composite having high thermal conductivity was prepared under low filling.When the sulfonated polyetheretherketone accounts for 10 wt.% by mass in the matrix,the thermal conductivity of the composite increases to 2.24 W/(m·K),which is 130% higher than that of the conventional carbon fiber/polyetheretherketone composite.At this time,the composite material still maintains excellent thermal and mechanical properties.In the second part of the experiment,graphite(C)and carbon fiber(CF)were used as thermal conductive fillers to prepare C/CF/PEEK composites with high thermal conductivity.A new high thermal conductivity filler C/SPEEK with SPEEK as the core and graphite as the core-shell structure of the shell was designed and synthesized.Through SPEEK as the charge mobility of the proton exchange membrane,it is charged after being treated in the electrostatic field,and naturally adsorbs graphite to form a core-shell structured packing.The carbon fiber with aspect ratio is designed and introduced to form a plurality of joint sites with the core-shell structured filler C/SPEEK to synergistically improve the thermal conductivity of the composite.The results show that under low filling,the heat conduction path and the heat conduction network have been formed in the polyetheretherketone composite,and the thermal conductivity is greatly increased.When the size of the core-shell filler is 1.0mm,when the degree of sulfonation of SPEEK in the core is 10%,the thermal conductivity of the composite exhibits a maximum value of 2.25 W/(m·K)compared to conventional graphite/polyetheretherketone.The composite material has been improved by 650%,and the composite material still maintains excellent thermal and mechanical properties.The research work of this thesis is based on PEEK,SPEEK and carbon material thermal conductive filler.The experiment uses double percolation theory,synergistic effect and core-shell structure to prepare polyether ether with high thermal conductivity under the condition of low mass fraction thermal conductive filler.Ketone composites.It is expected that the research results of this paper can provide some inspiration for the design and preparation of thermally conductive polymer materials.