Class transition temperatures and rigid amorphous fraction of poly(ether ether ketone) and polyarylate blends

The glass transition temperatures (T(g)s) and rigid amorphous fraction (X-r ) of the poly(ether ether ketone) (PEEK) and polyarylate (PAr) blends prepa red by screw extrusion have been investigated by differential scanning calo rimetry. From the measured T(g)s of PEEK and PAr in the PEEK-PAr blends, Fl ory-Huggins polymer-polymer interaction parameter (chi(12)) between PEEK an d PAr was calculated and found to be 0.058 +/- 0.002 at 360 degrees C. From the measured crystallinity and specific heat increment at T-g, the X-r of PEEK in the PEEK-PAr blends was calculated and found to be 0.31, 0.36, and 0.39 for the pure PEEK, 5:5, and 4:6 PEEK-PAr blends, respectively. The inc rease of X-r with PAr composition suggests that the PEEK crystalline become s less perfect by the addition of PAr in the PEEK-PAr blends. (C) 2000 Else vier Science Ltd. All rights reserved.