@article {Huang, title = {Novel hybrid of clay, cellulose, and thermoplastics. I. preparation and characterization of composites of ethylene-propylene copolymer}, journal = {Journal of Applied Polymer Science}, volume = {104}, number = {4}, year = {2007}, month = {MAY}, pages = {2672-2682}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

{The present study is aimed to prepare hybrid materials by incorporating layered silicates and microcrystalline cellulose into thermoplastic polymer. Using ethylene-propylene (EP) copolymer as thermoplastic polymer matrix and maleated EP (MEP) copolymer as compatibilizer, three types of composites were prepared by (i) melt mixing of cellulose with thermoplastics [

}, keywords = {abrupt contraction, Arbitrary Lagrangian Eulerian, finite element, simulations}, issn = {0957-4166}, doi = {10.1002/app.25659}, author = {Kumar, Annamalai Pratheep and Singh, Raj Pal} } @article { ISI:000266529600001, title = {Nanoscale particles for polymer degradation and stabilization-trends and future perspectives}, journal = {Progress in Polymer Science}, volume = {34}, number = {6}, year = {2009}, month = {JUN}, pages = {479-515}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

The field of nanoscience and nanotechnology is extending the applications of physics, chemistry, biology, engineering and technology into previously unapproached infinitesimal length scales. The polymer-nanoparticles/nanocomposites have been the exponentially growing field of research for developing the materials in last few decades and have been mainly focusing on the structure-property relationships and their development. Since the polymer-nanocomposites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. Thus, this article is intended to review the status of worldwide research in this aspect. Among various nanoparticulates, clay minerals and carbon nanotubes are more often used in enhancing physical, mechanical and thermal properties of polymers. In very few systems, the nano particulates have been incorporated into polymer as {\textquoteleft}nano-additives{\textquoteright} for both purposes: degradation and stabilization of polymers. The degradation and durability of polymers is reviewed in the presence of nanoparticles/nanocomposites under different environmental conditions. Nanoparticle-induced biodegradation of polymers is also discussed. (c) 2009 Elsevier Ltd. All rights reserved.

}, keywords = {Carbon nanotubes, clay, Degradation and stabilization, Nanocomposites, Nanoparticles, Polymer}, issn = {0079-6700}, doi = {10.1016/j.progpolymsci.2009.01.002}, author = {Kumar, Annamalai Pratheep and Depan, Dilip and Tomer, Namrata Singh and Singh, Raj Pal} } @article { ISI:000263423600001, title = {Novel allylic phosphonium salts in free radical accelerated cationic polymerization}, journal = {Polymer Bulletin}, volume = {62}, number = {3}, year = {2009}, month = {MAR}, pages = {271-280}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

In the present study, the synthesis and evaluation of novel allylic phosphonium salts as addition fragmentation agents in combination of conventional (photo-/thermal) free radical source for cationic polymerization are described. The amide based allylic phosphonium salts, namely 2-(N, N-dimethylcaboxy-propenyl) triphenylphosphonium hexafluoroantimonate (DMTPH) and 2-(morpholinocarboxy-propenyl) triphenyl phosphonium hexafluoroantimonate (MTPH) were synthesized and characterized. The thermal and photo-latency of these salts was examined with and without free radical sources in bulk polymerization of cyclohexene oxide (CHO) salts at 70 A degrees C and lambda \> 290 nm irradiation, respectively. In presence of thermal free radical source, the order of activity was observed as PAT \> BPO \> AIBN. The order of activity of free radical sources on photopolymerization was found to be benzoin \> benzophenone \> TMDPO. In addition, photopolymerization of other cationically polymerizable monomers (such as n-butyl vinyl ether, isobutyl vinyl ether, N-vinyl carbazole and glycidyl phenyl ether) was also examined at lambda \> 290 nm irradiation. It is concluded that the rate of cationic polymerization can be accelerated using novel phosphonium salts with combination of free radical sources, by both thermal and photochemical mode.

}, keywords = {Addition fragmentation agent, Cationic polymerization, Initiator, phosphonium salt, Photopolymerization}, issn = {0170-0839}, doi = {10.1007/s00289-008-0014-y}, author = {Gupta, Mukesh Kumar and Singh, Raj Pal} } @article { ISI:000265422100069, title = {Novel dibenzocycloheptenyl phosphonium salts as thermolatent initiator in cationic polymerization}, journal = {Journal of Applied Polymer Science}, volume = {112}, number = {6}, year = {2009}, month = {JUN}, pages = {3707-3713}, publisher = {JOHN WILEY \& SONS INC}, address = {111 RIVER ST, HOBOKEN, NJ 07030 USA}, abstract = {

In this study, novel thermolatent cationic initiators based on dibenzocycloheptenyl phosphonium salts (1a, 1b, 1c, 1d, 2a, and 3a) were synthesized and their efficiency was examined in bulk polymerization of glycidyl phenyl ether (GPE). The polymerization of GPE was performed with 1 mol \% of dibenzocycloheptenyl triphenylphosphonium salts (1a-1d) with different counter anions (SbF(6)(-), PF(6)(-), AsF(6)(-), and BF(4)(-)) at 25-200 degrees C for 1 h. The order of initiator activity was found as 1a \> 1d \> 1b \> 1c. To examine the effect of phosphine moiety, the activity of la was compared with dibenzocycloheptenyl-tri-n-butylphosphonium hexafluoroantimonate (2a). The order of initiator activity was observed as 1a \> 2a. The initiator activity of la was compared with that of 10,11-dihydro-dibenzocycloheptenyltriphenylphosphonium hexafluoroantimonate (3a) to understand the effect of extended conjugation in dibenzocycloheptenyl ring. In general, with the increase in the polymerization temperature, conversion (\%) also increases. The solubility of initiators in various solvents and epoxy monomers was also examined. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 3707-3713, 2009

}, keywords = {Cationic polymerization, glycidyl phenyl ether, initiators, phosphonium salt, thermolatent}, issn = {0021-8995}, doi = {10.1002/app.29518}, author = {Gupta, Mukesh Kumar and Singh, Raj Pal} } @article { ISI:000277449500003, title = {Novel addition-fragmentation agent in cationic photopolymerization}, journal = {Polymer Bulletin}, volume = {65}, number = {1}, year = {2010}, month = {JUN}, pages = {25-34}, publisher = {SPRINGER}, address = {233 SPRING ST, NEW YORK, NY 10013 USA}, abstract = {

The aim of present study is to examine the photo-initiation efficiency of N,N-dimethylacrylamide-based allylic ammonium salt as one component addition-fragmentation agent (cationic photoinitiator cum radical source) in free radical accelerated cationic polymerization. Novel addition-fragmentation agent (AFA), 2-(N,N-dimethylcarboxy-3-propenyl)(phenylcarbonyl-4-phenylene) dimethyl ammonium hexafluoroantimonate (DMPDA) was synthesized as cationic photoinitiator and its initiation efficiency was examined in polymerization of cyclohexene oxide (CHO), isobutyl vinyl ether (IBVE), and n-butyl vinyl ether (n-BVE) in CH(2)Cl(2) solvent at wavelength lambda \> 290 nm. The rate of polymerization increases with the increase in initiator concentration and reaction time. The results demonstrate that DMPDA acts as an efficient photoinitiator (AFA) without use of radical source in free radical accelerated cationic polymerization.

}, keywords = {Addition-fragmentation agent, Ammonium salt, Benzophenone, Cationic polymerization, Onium salt, Photopolymerization}, issn = {0170-0839}, doi = {10.1007/s00289-009-0182-4}, author = {Gupta, Mukesh Kumar and Mehare, Rupali S. and Singh, Raj Pal} }