The Surface Roughness On The Properties Of Mwcnts/pen Composite

In recent years, carbon nanotubes(CNT) has been widely concerned in physics, materials, machinery, biological and other fields due to its excellent physical and chemical properties. Carbon nanotubes as intensifying material is added to the polymer matrix to further improve the function of the composite material and expand the application prospect of composite materials,such as in electronic devices, biological sensors,photoelectric information materials and aerospace materials. Poly(arylene ether nitriles)(PEN),a new type of high performance thermoplastic special polymer materials, has high thermal stability, excellent mechanical properties and good chemical inertness, which promoted the polymer to the direction of high performance-based, functional and low cost of development. The CNT/PEN composite materials integrate advantages of both PEN and CNT, maintain the high thermal stability, excellent mechanical properties at the same time and also make up the disadvantage of PEN dielectric performance, which have a wide range of research. The key point of this paper is focused on the surface roughnesses and surface modification of CNT,which impact on the properties of composits. The composite materials will momentously came into play in electrical devices, aerospace and auto parts, etc. The concrete research content is as follows:(1). Firstly, acidulated and oxidized MWCNTs with different reaction time were prepared and surface roughnesses was characterized by AFM. The result shows that the suface of CNT has more and more carboxyl and hydroxyl groups with longer acidulating and oxidizing time, which impacted not only the kinds and amount of groups and also the length to diameter ratio of nanotubes. Finally its resulted in the coarser of the surface obtained MWCNT, which was characterized by AFM. The research has showed that the kinds and amount of groups and also the length to diameter ratio of nanotubes affect the distribution of CNT in the matrix and interfacial compatibility of the composites. MWCNT/PEN composites were then fabricated by using the solution-casting method with the acidulated and oxidized MWCNTs and PEN. It was studied in dielectric, thermal stability, mechanical and rheological. After making a comprehensive comparison of the acidulated and oxidized MWCNTs effect on the composites,the optimum processing time is 3 hours.(2). The carbon nanotubes was modified by 3-APN. The 3-APN@MWCNTs/PEN composite were obtained by using the solution-casting method to research the change ofperformance. After further study, the the dispersion of MWCNTs in matrix PEN has a greater degree of improvement and composite material interface compatibility is improved. In addition, the composites maintained the original the basis of thermodynamic properties and have been further improved in the dielectric and mechanical properties. Furthermore, the dielectric constant of the composite film increased to 32.2(50 Hz) and the corresponding dielectric loss was 0.9 with 5 wt% 3-APN@MWCNTs loading.(3) The carbon nanotubes was modified by Si O2. The Si O2@MWCNTs/PEN composite were obtained by using the solution-casting method to research the changes of performance. After further study, the the dispersion of MWCNTs in matrix PEN has a greater degree of improvement and composite material interface compatibility is improved. In addition, the composites maintained the original the basis of thermodynamic properties and have been further improved in the dielectric and mechanical properties. The results of mechanical tests showed that the tensile strength and modulus reached their highest values at the 2 wt% Si O2@MWCNTs loading content(125 MPa and 2950 MPa, respectively).