Study On Characteristics Of UHMWPE Filled With Crown-ether-copper And CNTs/PEKK Composite

There are two parts in this paper:A. Study on Characteristics of UHMWPE filled with Crown-ether-copperUHMWPE is a kind of engineering plastic with many outstanding physical and mechanical performances.But its melting viscosity is very tall,and moulding is difficult.As friction material with low friction coefficient and excellent wear-resistance,its heat-proof is bad,heat-conducting rate is low and the area of using temperature is narrow.In this subject, UHMWPE is modified by being filled with Crown-ether-copper,and its influence on the flowing property and the friction wear characteristics of UHMWPE is studied.The conclusion as follows:1. The complexes of copper nitrate and chloride with 18-C-6,15-C-5 are prepared,and characterized by element analysis,IR spectra and thermal analysis. Metal has no direct action with crown ether in 18-C-6 complex,and has direct action in 15-C-5 complex. The decomposing temperature of complex of copper nitrate with 15-C-5 is over the processing temperature of UHMWPE,so it is used filling in UHMWPE.2. The UHMWPE composites modified by Crown-ether-copper are prepared and tested on a friction and wear tester. The result showes: while adding a little amount of filler, the friction coefficient of the composite is reduced slightly and wear mass loss is increased a little;With the increace of adding filler, the friction coefficient nearly hold the line,but the wear mass loss is enhanced obviously. The flowing property of the composite is tested by melting instrument.The melting viscosity is reduced evidently with a little filler,and the flowing property is improved.B. Study on CNTs/PEKK compositepolyether-ketone-ketone(PEKK) is a kind of novel macromolecule material with excellent mechanical performances,radiation resistance,and so on. carbon nanotubes(CNTs) is of unique structure,outstanding mechanical,heat stability,electric conductivity.In this paper, CNTs/PEKK composite is prepared by means of insitupolymerization,and its properties are investigated. The conclusion as follows:1. PEKK is synthesized by means of low temperature solution polycondensation with diphenyl ether and terephthaloyl chloride as reaetants,l,2-dichloroethane as solvent and AlCl3/DMF as complex catalyst.2. several reaction conditions,such as the material amount,catalyst dosage,andreaction time,which affected the molecular weight of PEKK ,are investigated.The best reaction conditions: the mol ratio of the monocases is 1:1, the mol ratio of AlCl3/TPC is 3.8-4.2, the mol ratio of DMF/TPC is 1.8-2.2, the reaction time is 20 hours.3. PEKK is characterized by IR, TG, and DSC.Its major properties are determinedrthe intrinsic viscosity is over 0.8dl/g,the melting point is 372.2℃, the thermal decomposing temperature is 534℃.4. CNTs/ PEKK composites are prepared with different content of CNTs by means of insitupolymerization.Its dispersion is reviewed by SEM. CNTs are dispersed in PEKK matrix in the scale of nanometer without chemical processing,and packed tightly by PEKK matrix.The interface bonding is buildup between CNTs and PEKK.5. The melting point of PEKK can be lowered obviously in the scale of 30℃ by adding a little amount of CNTs(3(?)5%),and its heat-resistance property can be enhanced notably.