Study On Preparation And Properties Of Ti₃AlC₂/Epoxy Resin Conducting Composites

In this paper, Ti₃AlC₂ / epoxy resin (EP) conducting composites has been prepared using Ti₃AlC₂ as filler and epoxy resin as matrix by blending method. The effects of filler content, diluent and curing agent on properties of the composites were studied systematically. The main factors for composites properties were analyzed by microstructure observation. Non-linear ohmic formula was researched and the conductive mechanism of the composites was analyzed. The main conclusions are shown as follows.The volume resistivity and dielectric constant of TC₃AlC₂ / epoxy resin conducting composites appear percolation threshold effect. The critical value of Ti₃AlC₂ is 40wt%. Flexural properties of composite materials gradually increase with addition of Ti₃AlC₂ and reach the maximum when the mass fraction of Ti₃AlC₂ is 40%. But flexural properties decline when mass fraction of Ti₃AlC₂ is above 40wt%. The volume resistivity and flexural strength both gradually increase with increasing of the addition of polyamide (650) curing agent. When 650/EP is 50%, the combination property of the composites is the best. As the similar content, the combination property of sample using acid anhydride as curing agent is better than that of the sample using 650. C₂H₅OH has a better dispersion effect than ethylene glycol diglycidyl. The conductivity and dielectric properties of the C₂H₅OH sample are better than those of thylene glycol diglycidyl sample, while flexural strength is little lower. When the value of C₂H₅OH/EP is 15wt%, the combination property is the best among those of the samples with other C₂H₅OH/EP values.Ti₃AlC₂ / epoxy resin composites possess non-ohmic characteristic. With the increasing of the used voltage, the volume resistivity gradually decreases. And the relationship of 1gR and 1gU appears a good linear characteristic. The tunnel effect and electric conductivity launch may be the possible reasons to produce non-ohmic properties.