02782nas a2200241   4500008004100000022001400041245012500055210006900180260007500249300001200324490000700336520186000343653001902203653003702222653001502259653003402274653002202308100002002330700002502350700002002375700001802395856012702413       2006                        eng d  a1566-254300aPhoto-bio-degradability of agro waste and ethylene-propylene copolymers composites under abiotic and biotic environments0 aPhotobiodegradability of agro waste and ethylenepropylene copoly  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScAPR  a203-2120 v143 a<p>Composites were prepared by two methods, (i) graft copolymerization (GFC) of isotactic polypropylene (PP) with maliec anhydride, (MAH) followed by esterification with coir fiber and (ii) by direct reactive mixing (DFC) of polypropylene (PP) and ethylene-propylene (EP) copolymers with MAH and peroxide with coir fiber. These composites, after molding in films (5 x 5 cm, - 100 mu m thickness) were examined for susceptibility to biological attack by measuring the percentage weight loss in compost upto 6 months, periodically, and fungal colonization on surface of the samples, when kept as sole carbon source for the growth of Aspergillus niger in culture medium upto 40 days. Photodegradation was evaluated by monitoring the variations in FT-IR spectrum and crack formation after successive treatment with UV light (&gt;= 290 nm) for 0, 20, 50 and 100 h at 60 C in the presence of air. Specimens of virgin PP were taken as a reference during all period of photo and biodegradation studies. Significant changes were observed depending on the preparation methods during photodegradation and biodisintegration of composites. DFCs samples were disintegrated faster than GFCs during the composting whereas, in culture, GFCs were covered highly in well uniform way by fungi. It was observed that photo-oxidative ageing directly enhanced the biodegradability of composites as the increase in fungal growth rate and decrease in weight during composting were found. It was concluded that extent of compatibilization had a profound effect on photo-oxidation and biodisintegration of composite material; consequently ester bonds were main units during fungal consumption. Composition of monomers in copolymers was also showing significant effect on the degradability which decreased with increasing content of ethylene in ethylene-propylene (EP) copolymers.</p>10aBiodegradation10abiodisintegration and composting10acomposites10aethylene-propylene copolymers10aphoto-degradation1 aKumar, Pratheep1 aPandey, Jitendra, K.1 aKumar, Bijendra1 aSingh, R., P.  uhttps://library.ncl.res.in/content/photo-bio-degradability-agro-waste-and-ethylene-propylene-copolymers-composites-under-002479nas a2200265   4500008004100000022001400041245011100055210006900166260009900235300001400334490000700348520149400355653001701849653001801866653003301884653002401917653001801941653002301959100002601982700002002008700001902028700002102047700001802068856012702086       2006                        eng d  a0141-391000aStabilization of gamma-sterilized biomedical polyolefins by synergistic mixtures of oligomeric stabilizers0 aStabilization of gammasterilized biomedical polyolefins by syner  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcOCT  a2451-24640 v913 a<p>The stabilization of polyolefins against gamma-sterilization has been studied with single or binary additive system. The present attempt is to utilize synergistic mixtures of stabilizers which are approved for food contact applications. Ethylene-propylene (EP) copolymer has been melt-mixed with hindered amine stabilizers (HAS), phenolic antioxidants and organo-phosphites (hydroperoxide decomposer). Samples were sterilized with different doses of gamma-radiation. Stabilization was characterized in terms of changes in the functional groups (oxidation products), tensile properties, yellowing and surface morphology by FTIR spectroscopy, Instron, colorimetry (reflectance) and scanning electron microscopy (SEM), respectively. Results were discussed by comparing the stabilizing efficiency of mixtures with and without phenol system. Among phenol containing systems, where we mostly observe discoloration due to the oxidation of hindered phenol and the combination of secondary HAS, tertiary HAS, organo-phosphite and hindered phenol exhibited improved stabilization efficiency than single or binary additive systems. The mixture of secondary HAS and tertiary HAS, has shown antagonistic effect of stabilization whereas their combination with organo-phosphite has exhibited synergistic effect of stabilization even at higher doses of gamma-sterilization. The effects have been explained through the interaction between the stabilizers. (c) 2006 Elsevier Ltd. All rights reserved.</p>10aAntioxidants10adiscoloration10aethylene-propylene copolymer10agamma-sterilization10astabilization10atensile properties1 aAlariqi, Sameh, A. S.1 aKumar, Pratheep1 aRao, B., S. M.1 aTevtia, Amit, K.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/stabilization-gamma-sterilized-biomedical-polyolefins-synergistic-mixtures-oligomeric-202388nas a2200193   4500008004100000022001400041245010900055210006900164260009800233300001200331490000700343520154600350653003701896653006701933100002202000700002002022700002002042856013202062       2007                        eng d  a1042-714700aPhoto-stabilization of EPDM-clay nanocomposites: effect of antioxidant on the preparation and durability0 aPhotostabilization of EPDMclay nanocomposites effect of antioxid  aTHE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLANDbJOHN WILEY & SONS LTDcNOV  a891-9000 v183 a<p>The present study is to examine the photo-stabilization effect of an antioxidant on the photo-oxidation of ethylene-propylene-diene monomer (EPDM)-clay nanocomposites. During the preparation of EPDM-clay nanocomposites via melt processing antioxidants are usually incorporated along with clay, which allows phenolic antioxidant molecules to get adsorbed onto acidic clay platelets and their interaction with metallic impurities reduces the stabilizing efficiency of the antioxidant. The nanocomposites were obtained by solution dispersion followed by melt compounding of EPDM and organophilic montmorillonite (OMMT). The samples were characterized by conventional tools such as X-ray diffraction (XRD), Fourier Transform Infra Red (FT-IR) spectroscopy, and thermo-gravimetric analysis (TGA). It was found, upon photo-irradiation (lambda &gt; 290 nm) studies by following the changes in functional groups and surface morphology, that photo-degradation was lowered by the antioxidant and the efficiency of the antioxidant could be improved by initial incorporation of antioxidant in the EPDM matrix. In EPDM-clay nanocomposites, a stabilizing activity of the antioxidant was observed above some threshold concentration of the antioxidant. The relationship between the nanoclay reinforcement and stabilizing efficiency in terms of photo-oxidation and surface morphology for their applicability are discussed. The methodology adopted for this study is also justified through our observation. Copyright (C) 2007 John Wiley &amp; Sons, Ltd.</p>10aethylene-propylene-diene monomer10ananocomposites photo-degradation antioxidant and stabilization1 aLonkar, Sunil, P.1 aKumar, Pratheep1 aSingh, Raj, Pal  uhttps://library.ncl.res.in/content/photo-stabilization-epdm-clay-nanocomposites-effect-antioxidant-preparation-and-durability-000891nas a2200229   4500008004100000022001400041245014200055210006900197260007300266300001200339490000700351653001300358653002300371653002400394653001100418653002200429100002600451700002000477700001900497700001800516856012700534       2007                        eng d  a0167-577X00aStabilization of gamma-sterilized biomedical polyolefins by synergistic mixtures of oligomeric stabilizers. part II. polypropylene matrix0 aStabilization of gammasterilized biomedical polyolefins by syner  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB  a299-3090 v9210aCeramics10aChemical synthesis10aElectron microscopy10aOxides10aX-ray diffraction1 aAlariqi, Sameh, A. S.1 aKumar, Pratheep1 aRao, B., S. M.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/stabilization-gamma-sterilized-biomedical-polyolefins-synergistic-mixtures-oligomeric-102005nas a2200253   4500008004100000022001400041245011800055210006900173260009900242300001200341490000700353520106500360653001801425653001401443653002001457653002601477653001501503653001801518100002601536700002001562700001901582700001801601856013201619       2009                        eng d  a0141-391000aEffect of gamma-dose rate on crystallinity and morphological changes of gamma-sterilized biomedical polypropylene0 aEffect of gammadose rate on crystallinity and morphological chan  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcFEB  a272-2770 v943 a<p>The present work is aimed to study the changes in crystallinity and morphology of biomedical polyolefins after gamma-sterilization. The isotactic polypropylene (iPP) films were sterilized by gamma-radiation and the changes were characterized by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and atomic force microscopy (AFM) techniques. The effect of dose rate on crystallinity changes also was focused. It was found that crystallinity and morphology significantly changed with gamma-irradiation. There was an increase in crystallinity Lip to 10 kGy accompanied with decrease in viscosity and mechanical properties. The changes in crystallinity mainly depend on gamma-irradiation dose and dose rate. The rise in crystallinity was attributed to chain scission and forming new perfect lamellae. However, the reduction was accompanied by occurrence of gamma- and beta-phases and crosslinking. Possible explanations for transitions in phases are also discussed based on our results. (C) 2008 Elsevier Ltd. All rights reserved.</p>10aCrystallinity10aDose rate10aGamma radiation10amechanical properties10aMorphology10apolypropylene1 aAlariqi, Sameh, A. S.1 aKumar, Pratheep1 aRao, B., S. M.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/effect-gamma-dose-rate-crystallinity-and-morphological-changes-gamma-sterilized-biomedical-001562nas a2200241   4500008004100000022001400041245010800055210006900163260009200232300001200324490000600336520069000342653001501032653001201047653002401059653001801083653002001101653001701121100001801138700002501156700002001181856011901201       2009                        eng d  a1947-293500aSingle step synthesis and properties of M/MFe2O4 and PVDF/M/MFe2O4 (M = Co, Ni) magnetic nanocomposites0 aSingle step synthesis and properties of MMFe2O4 and PVDFMMFe2O4   a26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USAbAMER SCIENTIFIC PUBLISHERScDEC  a262-2680 v13 a<p>Metal/ferrite nanocomposites (M/MFe2O4; M = Co, Ni), consisting of nanoparticles of a metal and the corresponding metal ferrite, have been synthesized under in situ conditions by a simple and single step process. The metal/ferrite nanocomposites embedded in a polymer matrix have been prepared by a simple hot-pressing method. The performance parameters such as magnetization, coercivity, permeability and dielectric constant of the two- and three-phase nanocomposite systems are compared. The coercivity increases and the permeability decreases with increasing polymer content in the three-phase composite. Enhancement of the dielectric constant is observed at low frequencies.</p>10aDielectric10aFerrite10amagnetic properties10aNanocomposite10aNanocrystalline10apermeability1 aDeka, Sasanka1 aJoy, Pattayil, Alias1 aKumar, Pratheep  uhttps://library.ncl.res.in/content/single-step-synthesis-and-properties-mmfe2o4-and-pvdfmmfe2o4-m-co-ni-magnetic-0