@article { ISI:000243088200025, title = {Photooxidation of vulcanized EPDM/montmorillonite nanocomposites}, journal = {Polymer Degradation and Stability}, volume = {91}, number = {12}, year = {2006}, month = {DEC}, pages = {3033-3039}, publisher = {ELSEVIER SCI LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

The photooxidation of a vulcanized ethylene-propylene-diene monomer (EPDM)/montmorillonite nanocomposite as well as EPDM/nanocomposite with stabilizers was studied under accelerated UV-light irradiation (lambda \>= 300 nm, 60 degrees C) for different times. The development of functional groups during oxidation was monitored by infrared spectroscopy. Photodegradation of the neat polymer and composites took place and the increases of absorbance in hydroxyl and carbonyl groups with irradiation times and also the decreases of the EPDM unsaturations were measured. The data indicated that the photooxidation products were not changed in the presence of the nanofiller. However, the presence of MMt was observed to dramatically enhance the rate of photooxidation of EPDM with a shortening of the oxidation induction time, leading to a decrease of the durability of the nanocomposites. On the other hand, it was observed that addition of stabilizers, either Tinuvin P or 2-mercaptobenzimidazole, was efficient in inhibiting the degradative effect of MMt. (c) 2006 Elsevier Ltd. All rights reserved.

}, keywords = {EPDM, Nanocomposite, photooxidation rate, stabilization}, issn = {0141-3910}, doi = {10.1016/j.polymdegradstab.2006.08.026}, author = {Morlat-Therias, Sandrine and Fanton, Elisabeth and Tomer, Namrata S. and Rana, Sravendra and Singh, R. P. and Gardette, Jean Luc} } @article { ISI:000239688400001, title = {Preparation and performance evaluation of EPDM nanocomposites under accelerated weathering}, journal = {Journal of Thermoplastic Composite Materials}, volume = {19}, number = {5}, year = {2006}, month = {SEP}, pages = {461-474}, publisher = {SAGE PUBLICATIONS LTD}, type = {Article}, address = {1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLAND}, abstract = {

The degradability of ethylene propylene diene monomer (EPDM) nanocomposites, prepared from organically modified montmorillonite (CMMT), is studied under accelerated UV irradiation (lambda \>= 290 nm) for different time intervals. The development of functional groups during degradation is monitored by FT-IR spectroscopy whereas, surface changes are studied by scanning electron microscopy (SEM). The effect of clay modifier and clay concentration on the degradability are studied. The degradation of neat polymer and composites taking place traditionally and an increase in carbonyl and hydroxyl groups are observed with irradiation time. Neat EPDM is found to be less degradable than nanocomposites. Degradation products, as seen by FT-IR in nanocomposites are found to be the same as in neat polymer but are generated at a faster rate. According to the experimental results, one can define that both ammonium ion and neat montmorillonite (MMT) accelerate the photo-oxidation of EPDM.

}, keywords = {carbonyl index, Degradation, EPDM, layered silicates, Nanocomposites, photooxidation}, issn = {0892-7057}, doi = {10.1177/0892705706062204}, author = {Rana, Sravendra and Tevtia, Amit K. and Kumar, Bijendra and Singh, R. P.} } @article { ISI:000245141300053, title = {Photodegradation of ethylene/propylene/polar monomers, Co-, and terpolymers. II. prepared by Ni catalyst systems}, journal = {Journal of Applied Polymer Science}, volume = {104}, number = {3}, year = {2007}, month = {MAY}, pages = {1783-1791}, publisher = {WILEY-BLACKWELL}, type = {Article}, address = {COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA}, abstract = {

The copolymers of ethylene/propylene as well as their terpolymers with polar monomers were prepared by Ni-catalyst systems and their photodegradation behavior was studied by Fourier transform infrared spectroscopy. The polar monomers used to synthesize co- and terpolymers of ethylene/propylene/polar monomer were 5-hexen-1-ol, 10-undecen-1-ol, acrylamide, methylmethacrylate, acrylonitrile, and methylvinyl ketone. The morphological changes of the irradiated samples were determined by scanning electron microscopy. The photodegradation kinetics has also been studied. The surface damage caused by polychromatic irradiation (lambda \>= 290 nm) at 55 degrees C in atmospheric air is presented in different micrographs. The rate of photo-oxidative degradation is very fast in terpolymers containing polar monomers as compared with copolymers and homopolymers. The morphological study of the photodegraded samples showed a very good correlation with the photodegraded results. (c) 2007 Wiley Periodicals, Inc.

}, keywords = {copolymerization, Ethylene, Photodegradation, polar monomers, propylene}, issn = {0021-8995}, doi = {10.1002/app.25828}, author = {Fernandes, Susete N. and Correia, Sandra and Matos, Ines and Marques, Maria M. and Rana, Sravendra and Kumar, Bijandra and Gupta, M. K. and Singh, R. P.} }