Atom transfer radical copolymerization of phenoxycarbonylmethyl methacrylate with methylmethacrylate: Their monomer reactivity ratios and thermal stabilities

The atom transfer radical polymerization of phenoxycarbonylmethyl methacrylate (PCMMA) and its atom transfer radical copolymerization (ATRP) with methyl methacrylate (MMA) were performed in bulk at 110 °C in the presence of ethyl 2-bromoacetate, cuprous(I)bromide (CuBr), and 2,2'-bipyridine. Also, free-radical polymerization of PCMMA was carried out in the presence of 2,2'-azobisisobutyronitrile in 1,4-dioxane solvent at 60°C. The structure of homo and copolymers was characterized by IR, 1H and 13C NMR techniques. The composition of the copolymers was calculated from 1H-NMR spectra. The in situ addition of ethylmethacrylate to a macroinitiator of poly(phenoxycarbonylmethyl methacrylate) [Mn=32700, PD=1.53] afforded an AB-type block copolymer. The molecular weight and molecular weight distribution were obtained by Gel Permeation Chromatography (GPC). The polydispersity for the living copolymer (65%PCMMA units by mole) was 1.66. For copolymerization system, their monomer reactivity ratios were obtained by using both Kelen-Tüdös and Fineman-Ross equations. The initial decomposition temperatures of the resulting copolymers decreased with increasing mole fraction of PCMMA in them which indicates that heat resistance of copolymer have been improved by decreasing MMA units. The dielectric parameters of the homo- and copolymer were calculated at 1 KHz at different temperature. An increase in the dielectric constant is observed due to interfacial polarization

Thermal degradation of two different polymers bearing amide pendant groups prepared by ATRP method

Piperidinocarbonylmethyl methacrylate (PyCMMA) and 1-(piperidinocarbonyl) ethylmethacrylate (PyCEMA) monomers were synthesized. Polymerizations of PyCMMA and PyCEMA were carried out by atom transfer radical polymerization. The structure of monomers and polymers was characterized by 1 H-NMR, 13 C-NMR, and FT-IR spectroscopies. Characterization of poly(PyCMMA) and poly(PyCEMA) were carried out using differential scanning calorimetry and gel permeation chromatography. The experimental results showed that the reaction exhibited characteristics of controlled polymerization. The thermal degradation behaviors of poly(PyCEMA) and poly(PyCMMA) were studied using thermogravimetry and a single line vacuum system consisting of a degradation tube with a condenser for product collection. The poly(PyCEMA) and poly(PyCMMA) were heated from ambient temperature to 325 and 500 °C, respectively. The products of degradation were collected as a cold ring fraction (CRF). The CRFs of degradation were investigated by means of IR, 1 HNMR, and GC-MS. For the degradation of both polymers, the major products of CRFs are piperidinocarbonyl methanol and 1,2-dipiperidino,1-oxo ethane. The GC-MS, IR, and NMR data showed that depolymerization below 325 °C to the corresponding monomer was not prominantin the thermal degradation of poly(Py- CMMA). The mode of thermal degradation including formation of the major products was identified. © Akadémiai Kiadó, Budapest, Hungary 2013.Firat University Scientific Research Projects Management Unit: FUBAP-1650, FUBAP-656Acknowledgements The authors thank the Firat University Research Fund for financial support to these Projects (FUBAP-656 and FUBAP-1650)