Research on preparation and properties of PI-EP composite material

A series of PI-EP composite materials under different imidization temperature gradients were prepared from 3,3´-diethyl-4,4´-diamino diphenyl methane (DEDA DPM), benzop-henone tetracarboxylic acid dianhydride (BTDA) and epoxy resin (E-51), and thermal imide process was used. Fourier transform infrared spectroscopy (FI-TR) indicated that the chemical reactions between poly(amic acid) and epoxy resin was existence and imide ring had formed. Heat-resistant property, dielectric property and mechanical property of PI-EP composite materials were tested, respectively. The results showed that the order of the materials heat resistance was 493 K>;523 K>;473 K>; 453 K, dielectric constant and dielectric loss were ranged from 3.30~3.68 and 1.2×10^-3~1.3×10^-2, the shear strength of PI-EP-493 K was the best and attained maximum value 8.962 MPa, the adhesive forces of all composite materials were at the higher level (one or two level), fully met the applied requirement.