Copolymerization of two new kinds of methacrylate monomers and determination of monomer reactivity ratios

New methacrylate monomers 2-(p-methoxyphenoxy)-2-oxo-ethyl methacrylate (pMPOEMA), 2-(p-chlorophenoxy)-2-oxo-ethyl methacrylate (pCIPOEMA), and 2-oxo-2-phenylamino ethylene methacrylate (PAMA) were synthesized for the first time. The free-radical-initiated copolymerization of pMPOEMA and pCIPOEMA with PAMA was carried out in 1,4-dioxane Solution at 65 degrees C using 2,2'-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomers and copolymers were characterized by Fourier transform infrared, H-1 and C-13 NMR spectral Studies. The copolyrner compositions were evaluated from nitrogen content in polymers. The reactivity ratios of the monomers were determined by applying Fineman-Ross and Kelen-Tudos methods. The analysis of reactivity ratios revealed that pMPO-EMA and pCIPOEMA are less reactive than PAMA is, and copolymers formed are statistically in nature. The molecular weights ((M) over bar (w) and (M) over bar (n)) and polydispersity index of the polymers were determined using gel permeation chromatography. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with an increase in the mole fraction of pMPOEMA and pCIPOEMA in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of PAMA in the copolymers. (c) 2006 Wiley Periodicals, Inc.