الفهرس 
INTRODUCTION & LITERATUREOnly 14 pages are availabe for public view
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Abstract
Two novel acrylamide monomers 4-(4`-cyanophenoxy) phenyl acrylamide (CPPAM) and 4-(4`- trifluoromethyl) phenoxy N-phenyl acrylamide monomer (FPPAM) have been synthesized and characterized by elemental analysis and spectral methods (13C-NMR, 1H-NMR, FTIR). The free radical polymerization of CPPAM and FPPAM was initiated by azobisisobutyronitrile in THF and 1, 4 dioxane respectively. The effects of monomer and initiator concentrations on the rate of polymerization have been determined dilatometrically and it was found that the polymerization reaction of these compounds follows the conventional free radical mechanism. The effect of temperature on the rate and degree of polymerization was also studied and it was found that increasing the reaction temperature usually increases the polymerization rate and decreases the polymer molecular weight. The activation energy E of the polymerization was calculated and it was found to be equal to 21.1 kJ/ mol for PCPPAM and 29.5 kJ/ mol for PFPPAM. These values were found in the range, in most cases, of free radical polymerization.
The initial rate of polymerization was measured and the rate equation was established as Rp= kp(kd/kt)0.5 [I]0.57[M]1.1 for PCPPAM and Rp= kp(kd/kt)0.5 [I]0.56[M]1.12 for PFPPAM. The intrinsic viscosity of the prepared polymers was calculated and it was found that the intrinsic viscosity [] increases with increasing monomer concentration and decreases with increasing the initiator concentration and temperature which is a well expected behavior for free radical polymerization. The weight average (Mw) and number average (Mn) molecular weight and polydispersity index (Mw/ Mn) of the poly-FPPAM sample were obtained from gel permeation chromatography. The values of weight average and number average molecular weight of PFPPAM were equal to 411,061 and 129,046, respectively. The polydispersity index of the poly-FPPAM was equal to 3.185. The data indicate that the prepared poly-FPPAM has high molecular weight. The polymers exhibit good solubility in some solvents.
The thermal analysis data of PCPPAM and PFPPAM indicated that the two polymers have an excellent thermal stability as well as the photo stability. The glass transition temperature (Tg) of PCPPAM and PFPPAM was determined by DSC and was found to be about 353oC and 285oC respectively.
The monomer reactivity ratios (r1&r2) for the copolymerization of CPPAM and FPPAM (M1) with methyl methacrylate (MMA, M2), vinyl acetate (VAc, M2) and acrylonitrile (AN, M2) were calculated by three different methods, Finman – Ross, Kelen - Tüdos and non linear least square method. CPPAM r1 was 0.102 with MMA, 1.24 with VAc and 0.66 with AN, while r2 was 0.095 with MMA, 0.1158 with VAc and 0.134 with AN. FPPAM r1 was 0.13 with MMA, 0.051 with VAc and 0.14 with AN. while r2 was 0.037 with MMA, 0.163 with VAc and 0.513 with AN.
The thermal analysis of the copolymers of FPPAM and CPPAM with VAc, AN, and MMA was investigated. Also, the activation energy of degradation was calculated by using Dharwadkar and Kharkhanavala equation. Copolymerization of CPPAM and FPPAM with MMA and VAc were found to improve the thermal stability of MMA, VAc and AN polymers.