LASER LIGHT-SCATTERING STUDY OF NOVEL THERMOPLASTICS .1. PHENOLPHTHALEIN POLY(ARYL ETHER KETONE)

Five different molecular weight phenolphthalein poly(aryl ether ketone ) (PEK-C) fractions in CHCl3 were studied by static and dynamic laser light scattering(LLS). The dynamic LLS revealed that the PEK-C samples contain some large polymer clusters. These large clusters can be remo ved by filtering the solution with a 0.1-mu m filter. We found that th e persistence length of PEK-C in CHCl3 at 25 degrees C is similar to 2 nm and the Flory characteristic ratio, C-infinity is similar to 25. O ur results showed that [R(g)(2)](1/2)(z) = (3.50+/-0.20) x 10(-2)M(w)( 0.54+/-0.01) and [D] = (2.37+/-0.05) x 10(-4)M(w)(-0.55+/-0.01), with [R(g)(2)](1/2)(z), M(w), and [D] being the z-average radius of gyratio n, the weight-average molecular weight, and the z-average translationa l diffusion coefficient, respectively. A combination of static and dyn amic LLS results enabled us to determine D = (2.20+/-0.10) x 10(-4)M(- 0.555+/-0.015), where D and M correspond to monodisperse species. Usin g this calibration between D and M,we have determined molecular weight distributions of five PEK-C fractions from their corresponding transl ational diffusion coefficient distribution.