02094nas a2200241   4500008004100000022001400041245014100055210006900196260008700265300001200352490000700364520116000371653002201531653001501553653001501568653002601583653003101609653003601640100001801676700001701694700001801711856012301729       2005                        eng d  a0892-705700aDurability of natural fiber-reinforced composites of ethylene-propylene copolymer under accelerated weathering and composting conditions0 aDurability of natural fiberreinforced composites of ethyleneprop  a1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLANDbSAGE PUBLICATIONS LTDcNOV  a489-5080 v183 a<p>Three types of composites are prepared by the melt mixing of ethylene-propylene copolymer (EPC) with (i) 3 % NaOH-treated jute fiber, (ii) 17.5 % NaOH-treated jute fiber, and (iii) commercial microcrystal line cellulose powder using maleated EPC as compatibilizer. The composites obtained are characterized by FTIR and microscopic measurements. Their mechanical properties are measured using a UTM (Instron model 4204). The durability of the composites is evaluated in an irradiation chamber with UV radiation of wavelength lambda &gt;= 290 mn and composting conditions at different time intervals. The composites made from microcrystalline cellulose show superior mechanical properties, biodisintegrability, as well as photoresistance whereas the specimen containing 3% NaOH-treated fiber exhibited the lowest photoresistance. Increasing the quantity of maleated EP (MEP) in the composition decreases photostability. Neat EPC has been found to be highly stable than all the composites with increasing UV irradiation. It has been found that the composites are less durable under both abiotic and biotic conditions in comparison to the neat polymer.</p>10acompatibilization10acomposites10ajute fiber10amechanical properties10aMicrocrystalline cellulose10aphotodegradation and composting1 aKumar, A., P.1 aDepan, Dilip1 aSingh, R., P.  uhttps://library.ncl.res.in/content/durability-natural-fiber-reinforced-composites-ethylene-propylene-copolymer-under-002148nas a2200289   4500008004100000022001400041245009200055210006900147260006900216300001400285490000800299520114100307653003301448653002801481653002601509653002901535100001801564700001801582700001801600700001901618700001901637700002201656700002101678700001801699700002301717856011801740       2005                        eng d  a0022-328X00aHighly active new alpha-diimine nickel catalyst for the polymerization of alpha-olefins0 aHighly active new alphadiimine nickel catalyst for the polymeriz  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcMAR  a1314-13230 v6903 a<p>A new silylated alpha-diimine ligand, bis[N,N `-(4-tert-butyl-diphenylsilyl-2,6-diisopropylphenyl)imino]acenaphthene 3, and its corresponding Ni(II) complex, {bis[N,N `-(4-tert-butyl-diphenylsilyl-2,6-diisopropylphenyl)imino]acenaphthene} dibromonickel 4, have been synthesized and characterized. The crystal structures of 3 and 4 were determined by X-ray crystallography. In the solid state, complex 4 is a dimer with two bridging Br ligands linking the two nickel centers, which have square pyramidal geometries. Complex 4, activated either by diethylaluminum chloride (DEAC) or methylaluminoxane (MAO) produces very active catalyst systems for the polymerization of ethylene and moderately active for the polymerization of propylene. The activity values are in the order of magnitude of 10(7) g PE (mol Ni [E] h)(-1) for the polymerization of ethylene and of 10(5) g PP (mol Ni [P] h)(-1) for the polymerization of propylene. NMR analysis shows that branched polyethylenes (PE) are obtained at room or higher temperatures and almost linear PE is obtained at 0 degrees C with 4/DEAC. (c) 2004 Elsevier B.V. All rights reserved.</p>10aalpha-diimine nickel complex10aEthylene polymerization10alate transition-metal10apropylene polymerization1 aLiu, Hua-Rong1 aGomes, P., T.1 aCosta, S., I.1 aDuarte, M., T.1 aBranquinho, R.1 aFernandes, A., C.1 aChien, J., C. W.1 aSingh, R., P.1 aMarques, Maria, M.  uhttps://library.ncl.res.in/content/highly-active-new-alpha-diimine-nickel-catalyst-polymerization-alpha-olefins-101687nas a2200265   4500008004100000022001400041245012000055210006900175260008600244300001400330490000800344520071500352653002701067653002101094653001901115100002601134700002001160700001901180700001801199700001301217700002201230700002301252700001801275856012801293       2005                        eng d  a1060-132500aPhotodegradation of ethylene/propylene/polar monomers co- and terpolymers. I - Prepared by group 4 catalyst systems0 aPhotodegradation of ethylenepropylenepolar monomers co and terpo  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcSEP  a1259-12700 vA423 a<p>The photooxidative degradation behavior of polyethylene, its copolymers (propylene/polar monomers) and terpolymers, synthesized by a group 4 catalyst system, has been studied by Fourier transform infrared spectroscopy and confirmed with scanning elecrton microscopy for morphological changes. The kinetics of photodegradation has also been studied. Surface damage caused by polychromatic (&gt;= 290 nm) at 55 degrees C in air is presented in different micrographs. The rate of photodegradation is very fast in terpolymers containing polar monomers as compared with copolymers and polyethylene. Morphological study of these photodegraded samples showed a very good relation with photodegradation results.</p>10afunctional polyolefins10aPhotodegradation10aUV irradiation1 aFernandes, Susete, N.1 aCorreia, Sandra1 aPrasad, A., V.1 aReddy, K., R.1 aRana, S.1 aLonkar, Sunil, P.1 aMarques, Maria, M.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/photodegradation-ethylenepropylenepolar-monomers-co-and-terpolymers-i-prepared-group-4-002043nas a2200289   4500008004100000022001400041245005200055210005200107260009200159300001200251490000600263520113800269653001401407653003701421653001801458653002401476653002901500653002001529653001101549100001901560700001801579700001401597700002001611700001801631700001801649856008601667       2005                        eng d  a1533-488000aRecent advances in biodegradable nanocomposites0 aRecent advances in biodegradable nanocomposites  a26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USAbAMER SCIENTIFIC PUBLISHERScAPR  a497-5260 v53 a<p>There is growing interest in developing bio-based products and innovative process technologies that can reduce the dependence on fossil fuel and move to a sustainable materials basis. Biodegradable bio-based nanocomposites are the next generation of materials for the future. Renewable resource-based biodegradable polymers including cellulosic plastic (plastic made from wood), corn-derived plastics, and polyhydroxyalkanoates (plastics made from bacterial sources) are some of the potential biopolymers which, in combination with nanoclay reinforcement, can produce nanocomposites for a variety of applications. Nanocomposites of this category are expected to possess improved strength and stiffness with little sacrifice of toughness, reduced gas/water vapor permeability, a lower coefficient of thermal expansion, and an increased heat deflection temperature, opening an opportunity for the use of new, high performance, lightweight green nanocomposite materials to replace conventional petroleum-based composites. The present review addresses this green material, including its technical difficulties and their solutions.</p>10acellulose10alayered silicates and properties10aNanocomposite10apoly(caprolactone)s10apoly(hydroxy alkanoate)s10apolyiactic acid10aStarch1 aPandey, J., K.1 aKumar, A., P.1 aMisra, M.1 aMohanty, A., K.1 aDrzal, L., T.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/recent-advances-biodegradable-nanocomposites-001934nas a2200241   4500008004100000022001400041245013900055210006900194260006800263300001200331490000700343520104200350653002001392653000801412653003801420653001501458653001801473653000801491100002201499700002101521700001801542856013201560       2005                        eng d  a0887-626600aStudies on characterization of nano CaCO3 prepared by the in situ deposition technique and its application in PP-nano CaCO3 composites0 aStudies on characterization of nano CaCO3 prepared by the in sit  a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcJAN  a107-1130 v433 a<p>The elegant approach of in situ deposition technique was used for the synthesis of nano CaCO3 the nanosize of particles was confirmed by the X-ray diffraction (XRD) technique. Differential scanning calorimetry (DSC) was used for determination of the enthalpy. The nano CaCO3 polypropylene (PP) composites were prepared by taking 2 and 10 wt % of different nanosizes (21-39 nm) of CaCO3. Conversion of the alpha phase to beta was observed in the case of 2 wt % of a 30-nm sized amount of CaCO3 in a PP composite. The decrement in DeltaH and percent. crystallinity, as well as the increment in melt temperature were recorded for 6 wt % nano CaCO3 with a decrease in nanosize from 39 to 21 nm. The increment in tensile strength with an increase in the amount of nano CaCO3 was observed, and the tower particle size shoved Greater improvement. The improvement in thermal and mechanical properties is because of the formation of a greater number of small spherulites uniformly present in the PP matrix. (C) 2004 Wiley Periodicals, Inc.</p>10aCrystallization10aDSC10amechanical and thermal properties10anano CaCO310apolypropylene10aXRD1 aMishra, Satyendra1 aSonawane, S., H.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/studies-characterization-nano-caco3-prepared-situ-deposition-technique-and-its-application-001649nas a2200205   4500008004100000022001400041245014100055210006900196260006800265300001000333490000700343520086500350100001801215700001801233700001301251700002201264700001701286700001801303856012201321       2005                        eng d  a1083-560100aSynthesis, characterization, and performance evaluation of novel stabilized TDI-based polyurethane coatings under accelerated weathering0 aSynthesis characterization and performance evaluation of novel s  a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcMAR  a13-200 v113 a<p>Some toluene dilsocyanate (TDI)-based polyurethane resins (PURs) for coating applications were synthesized with castor oil and their performance was estimated under accelerated UV weathering with and without a novel UV absorber. Changes in physical properties, chemical structure, and color of the samples were monitored by mechanical property testing, FTIR spectroscopy, and colorimetry, respectively. A stable polyurethane coating was achieved at 0.5% concentration of additive in the host matrix. Mechanical properties were also retained as in the pristine PUR after mixing. Commercial Tinuvin P and benzotriazole-based novel UV absorbers were found to improve the photoresistance of the PUR coating, and the highest efficiency of the novel UV absorber against weathering was estimated at 0.5 wt% concentration.(c) 2005 Society of Plastics Engineers.</p>1 aKumar, A., P.1 aReddy, K., R.1 aRana, S.1 aLonkar, Sunil, P.1 aRaut, K., G.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/synthesis-characterization-and-performance-evaluation-novel-stabilized-tdi-based-001691nas a2200265   4500008004100000022001400041245012400055210006900179260008600248300001400334490000800348520073300356653000901089653002701098653002301125653001901148100002201167700001301189700001801202700002101220700002401241700001501265700001601280856012901296       2005                        eng d  a1060-132500aSynthesis, characterization, and performance evaluation of polymeric HALS in ethylene-propylene-diene terpolymer (EPDM)0 aSynthesis characterization and performance evaluation of polymer  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcAUG  a1037-10460 vA423 a<p>A polymeric hindered amine light stabilizer (HALS), wherein the hindered amine functionality was attached to the maleic anhydride graft ethylene-propylene-diene terpolymer (EPDM) was synthesized. This involves photoinduced grafting of maleic anhydride groups on unsaturated sites of EPDM, followed by incorporation of amino terminated HALS. The grafting and functionalization reactions were characterized by FTIR and C-13 NMR spectroscopy. The surface changes upon degradation are studied by SEM. The photostabilizing efficiency of this polymeric HALS was studied and compared with conventional HALS under accelerated weathering conditions. The HALS grafted EPDM showed significantly improved photostabilizing efficiency.</p>10aEPDM10alight induced grafting10aPhotostabilization10apolymeric HALS1 aLonkar, Sunil, P.1 aRana, S.1 aSingh, R., P.1 aLacoste, Jacques1 aGardette, Jean, Luc1 aJestin, F.1 aBrocord, E.  uhttps://library.ncl.res.in/content/synthesis-characterization-and-performance-evaluation-polymeric-hals-ethylene-propylene-002185nas a2200241   4500008004100000022001400041245011100055210006900166260009900235300001400334490000700348520126300355653001901618653001901637653003401656653002401690653001601714100002601730700001801756700001901774700001801793856013201811       2006                        eng d  a0141-391000aBiodegradation of gamma-sterilised biomedical polyolefins under composting and fungal culture environments0 aBiodegradation of gammasterilised biomedical polyolefins under c  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcMAY  a1105-11160 v913 a<p>Polyolefin-based commodities are widely used as biomedical devices and food packaging after gamma-sterilisation. The aim of the present work was to study the effect of gamma-sterilisation on the biodegradation of polyolefins. Films of isotactic polypropylene, high-density polyethylene and ethylene-propylene (EP) copolymers were sterilised under gamma-radiation with doses of 10 and 25 kGy. Neat and sterilised samples were incubated in compost and fungal culture environments. The changes in functional groups, surface morphology and chain scission in polymer chains were characterized by FTIR spectroscopy, SEM and viscometric measurements, respectively. A gradual decrease in intrinsic viscosity [eta] and increase in carbonyl and hydroxyl regions in FTIR spectra were found for the gamma-sterilised samples as a function of increasing dose. Polypropylene was found to be more susceptible to both radio-oxidation and biodegradation. It was observed that in case of ethylene-propylene copolymers, extent of gamma-sterilisation and/or biodegradation depends on the composition and distribution of comonomers. Important surface erosion was detected by SEM, for higher sterilisation doses, after composting. (c) 2005 Elsevier Ltd. All rights reserved.</p>10aBiodegradation10achain scission10aComposting and fungal culture10agamma-sterilisation10aPolyolefins1 aAlariqi, Sameh, A. S.1 aKumar, A., P.1 aRao, B., S. M.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/biodegradation-gamma-sterilised-biomedical-polyolefins-under-composting-and-fungal-culture-101874nas a2200169   4500008004100000022001400041245012700055210006900182260008900251300002000340520113000360100002701490700001801517700001801535700002101553856013001574       2006                        eng d  a1618-722900aCharacterization of polydimethylsiloxane rubber upon photochemical, thermal, salt-fog ageings and exposure to acid vapours0 aCharacterization of polydimethylsiloxane rubber upon photochemic  a1, QUAI LEZAY-MARNESIA, F067000 STRASBOURG, FRANCEbEUROPEAN POLYMER FEDERATIONcMAY  aArticle No. 0133 a<p>The changes in the chemical structure and the physical properties of a filled crosslinked polydimethylsiloxane rubber were monitored as a function of various ageing factors. The variables included photochemical, thermal, salt-fog ageings and exposure to acid vapours. Unaged and aged samples were studied by IR spectroscopy, hardness measurements, Differential Scanning Calorimetry (DSC) and thermogravimetric analysis (TGA) coupled with IR spectroscopy. No significant oxidation was detected after all ageings, except for nitric acid treatment. The presence of aluminium trihydrate was clearly identified as responsible for the observed chemical changes. Then an important vulnerability of this filled silicone rubber towards the cross-linking reactions provoked by usual ageings was also detected. The DSC-thermoporosimetry measurements of the mesh size distribution gave a comparison of cross-linking densities for each ageing. The complementary analysis with TGA-IR allowed us to differenciate the thermal stability of the formulation after various ageings and to acquire new knowledge about thermal decomposition.</p>1 aDelor-Jestin, Florence1 aTomer, N., S.1 aSingh, R., P.1 aLacoste, Jacques  uhttps://library.ncl.res.in/content/characterization-polydimethylsiloxane-rubber-upon-photochemical-thermal-salt-fog-ageings-102782nas 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-001984nas a2200253   4500008004100000022001400041245006900055210006800124260009900192300001400291490000700305520111100312653000901423653001801432653002401450653001801474100002901492700002201521700002301543700002001566700001801586700002401604856010201628       2006                        eng d  a0141-391000aPhotooxidation of vulcanized EPDM/montmorillonite nanocomposites0 aPhotooxidation of vulcanized EPDMmontmorillonite nanocomposites  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcDEC  a3033-30390 v913 a<p>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 &gt;= 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.</p>10aEPDM10aNanocomposite10aphotooxidation rate10astabilization1 aMorlat-Therias, Sandrine1 aFanton, Elisabeth1 aTomer, Namrata, S.1 aRana, Sravendra1 aSingh, R., P.1 aGardette, Jean, Luc  uhttps://library.ncl.res.in/content/photooxidation-vulcanized-epdmmontmorillonite-nanocomposites-001891nas a2200253   4500008004100000022001400041245009500055210006900150260008700219300001200306490000700318520100000325653001901325653001601344653000901360653002201369653001901391653001901410100002001429700002101449700002001470700001801490856012901508       2006                        eng d  a0892-705700aPreparation and performance evaluation of EPDM nanocomposites under accelerated weathering0 aPreparation and performance evaluation of EPDM nanocomposites un  a1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLANDbSAGE PUBLICATIONS LTDcSEP  a461-4740 v193 a<p>The degradability of ethylene propylene diene monomer (EPDM) nanocomposites, prepared from organically modified montmorillonite (CMMT), is studied under accelerated UV irradiation (lambda &gt;= 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.</p>10acarbonyl index10aDegradation10aEPDM10alayered silicates10aNanocomposites10aphotooxidation1 aRana, Sravendra1 aTevtia, Amit, K.1 aKumar, Bijendra1 aSingh, R., P.  uhttps://library.ncl.res.in/content/preparation-and-performance-evaluation-epdm-nanocomposites-under-accelerated-weathering-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-201621nas a2200241   4500008004100000022001400041245009700055210006900152260009900221300001200320490000700332520075000339653001101089653000901100653001401109653002101123653002201144100001801166700002701184700001801211700002101229856012901250       2007                        eng d  a0141-391000aCross-linking assessment after accelerated ageing of ethylene propylene diene monomer rubber0 aCrosslinking assessment after accelerated ageing of ethylene pro  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcMAR  a457-4630 v923 a<p>The ageing of filled and cross-linked ethylene propylene diene elastomer (EPDM) has been studied under accelerated UV irradiation (lambda &gt;= 290 nm) at 60 degrees C, thermal ageing at 100 degrees C and in nitric acid vapours for different time intervals. Hardness measurements were performed. DSC-thermoporosimetry was used to estimate the mesh size distribution and cross-linking densities for each ageing. The development of functional groups was monitored by ATR spectroscopy. An increase in oxidation with exposure time after the different types of ageing was observed. The thermal stability of EPDM was assessed by TGA and evolved volatile gases were identified using FTIR spectroscopy. (c) 2006 Elsevier Ltd. All rights reserved.</p>10aageing10aEPDM10aOxidation10athermal analysis10athermoporosimetry1 aTomer, N., S.1 aDelor-Jestin, Florence1 aSingh, R., P.1 aLacoste, Jacques  uhttps://library.ncl.res.in/content/cross-linking-assessment-after-accelerated-ageing-ethylene-propylene-diene-monomer-rubber02030nas a2200289   4500008004100000022001400041245011700055210006900172260007600241300001400317490000800331520102100339653002101360653001301381653002101394653001901415653001401434100002601448700002001474700001601494700002301510700002001533700002001553700001801573700001801591856013101609       2007                        eng d  a0021-899500aPhotodegradation of ethylene/propylene/polar monomers, Co-, and terpolymers. II. prepared by Ni catalyst systems0 aPhotodegradation of ethylenepropylenepolar monomers Co and terpo  aCOMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USAbWILEY-BLACKWELLcMAY  a1783-17910 v1043 a<p>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 &gt;= 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.</p>10acopolymerization10aEthylene10aPhotodegradation10apolar monomers10apropylene1 aFernandes, Susete, N.1 aCorreia, Sandra1 aMatos, Ines1 aMarques, Maria, M.1 aRana, Sravendra1 aKumar, Bijandra1 aGupta, M., K.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/photodegradation-ethylenepropylenepolar-monomers-co-and-terpolymers-ii-prepared-ni-catalyst01679nas a2200217   4500008004100000022001400041245011400055210006900169260010000238300001200338490000600350520084700356653000901203653003001212653002001242653002301262100001401285700001301299700001801312856013101330       2007                        eng d  a1788-618X00aPhoto-oxidation of EPDM/layered double hydroxides composites: influence of layered hydroxides and stabilizers0 aPhotooxidation of EPDMlayered double hydroxides composites influ  aDEPT POLYMER ENG, MUEGYETEM RKP 3, BUDAPEST, H-1111, HUNGARYbBUDAPEST UNIV TECHNOL & ECONcNOV  a748-7540 v13 a<p>The photo-oxidation of ethylene propylene diene monomer (EPDM)/layered double hydroxide (LDH) composites as well as EPDM/LDH with stabilizers is studied under accelerated UV irradiation (lambda &gt;= 290 nm) at 60 degrees C for different time intervals. The development of functional groups during oxidation was monitored by FT-IR spectroscopy. The photo-degradation of the pristine polymer and composites take place and the increase in hydroxyl and carbonyl groups with irradiation times, was estimated. EPDM filled LDH showed higher degradation rate than pristine EPDM, while in acidic medium EPDM/LDH showed almost equal degradation as in isolated conditions. These results show the advantages of LDHs as a filler as well as an acid killer. The effect of stabilizers is very less because of their concentration in comparison of LDH.</p>10aEPDM10alayered double hydroxides10aPhoto-oxidation10apolymer composites1 aKumar, B.1 aRana, S.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/photo-oxidation-epdmlayered-double-hydroxides-composites-influence-layered-hydroxides-and-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-101801nas a2200253   4500008004100000022001400041245011900055210006900174260006800243300001400311490000800325520084700333653002601180653003401206653001901240653001801259653003801277100002201315700002001337700002001357700002101377700001801398856013101416       2007                        eng d  a0021-899500aSynthesis and characterization of hindered amine light stabilizers based on end functionalization of polypropylene0 aSynthesis and characterization of hindered amine light stabilize  a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcMAY  a1596-16020 v1043 a<p>A polymeric hindered amine light stabilizer (HALS), where HALS moiety was attached at the terminal end of the polypropylene chain via end-functionalized vinylidine PP through simple organic reactions, was synthesized. It comprises the synthesis of vinylidine-terminated polypropylene by using Cp2ZrCl2/MAO as catalyst system and epoxidation of vinylidene polypropylene. The final product was synthesized by carrying out the reaction between epoxy end functionalized polypropylene and 4-amino-2,2,6,6-tetrametyl piperidine. The final product was characterized by using H-1 NMR, C-13 NMR, and FT-IR spectra. Functionality was calculated by using vapor phase osmometry and H-1 NMR. The solubility and diffusion coefficient of the product were calculated and also its stabilization performance was checked. (c) 2007 Wiley Periodicals, Inc.</p>10aend functionalization10afunctionalization of polymers10apolymeric HALS10apolypropylene10avinylidine and photostabilization1 aReddy, Raghunatha1 aKumar, Bijendra1 aRana, Sravendra1 aTevtia, Amit, K.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/synthesis-and-characterization-hindered-amine-light-stabilizers-based-end-functionalization02005nas 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-002284nas a2200205   4500008004100000022001400041245010900055210006900164260007300233300001000306490000800316520147300324653003101797653002901828653002101857653003301878100002201911700001801933856012701951       2009                        eng d  a0040-603100aIsothermal crystallization and melting behavior of polypropylene/layered double hydroxide nanocomposites0 aIsothermal crystallization and melting behavior of polypropylene  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL  a63-700 v4913 a<p>The effect of layered double hydroxide (LDH) nanolayers on the crystallization behavior of polypropylene (PP) was studied based on the preparation of nanocomposites by a melt intercalation method. The isothermal crystallization kinetics and subsequent melting behavior of PP/LDH hybrids were studied with differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide-angle X-ray diffraction (WAXD). Studies revealed that the LDH promoted heterogeneous nucleation, accelerating the crystallization of PR The Avrami equation successfully describes the isothermal crystallization kinetics of PP/LDH hybrids and signifies heterogeneous nucleation in crystal growth of PR The varying values of Avrami exponent (n) and half crystallization time (t(1/2)) of PP and PP/LDH hybrids describes overall crystallization behavior. The crystallite size (D(hkl)) and distribution of different crystallites in PP varied in presence of LDH. A significant increase in melting temperature is observed for PP/LDH hybrids. The POM showed that smaller and less perfect crystals were formed in nanocomposites because of molecular interaction between PP chains and LDH. The value of fold surface free energy (sigma(e)) of PP chains decreased with increasing LDH content. Finally, the overall results signify that LDH at nanometer level acted as nucleating agent and accelerate the overall crystallization process of PR (C) 2009 Elsevier B.V. All rights reserved.</p>10aIsothermal crystallization10aLayered double hydroxide10aMelting behavior10aPolypropylene nanocomposites1 aLonkar, Sunil, P.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/isothermal-crystallization-and-melting-behavior-polypropylenelayered-double-hydroxide-001674nas a2200169   4500008004100000022001400041245007600055210006900131260006700200300001200267490000700279520105600286100002001342700001901362700001801381856010501399       2009                        eng d  a0272-839700aPhotodegradation of EPDM/MWCNT nanocomposites: effect of singlet oxygen0 aPhotodegradation of EPDMMWCNT nanocomposites effect of singlet o  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcJUL  a855-8600 v303 a<p>The photo-oxidation of ethylene propylene diene monomer (EPDM)/multiwall carbon nanotubes (MWCNT) nanocomposites has been studied under accelerated UV-irradiation (lambda &gt;= 290 nm) in the presence of singlet oxygen. The rate of photodegradation of EPDM/MWCNT is found to be higher when compared to the pristine polymer in presence of singlet oxygen. The enhancement of the rate of degradation of composite has been described through [2 + 2] photocycloaddition reaction between singlet oxygen and double bonds on composite which is followed by cleavage. The rate of degradation and the formation of new functional groups on the composite has been monitored by FTIR spectroscopy and found to be increased with irradiation time. The changes in surface morphology have been studied by scanning electron microscope. Differential scanning calorimetry measurements revealed an increase in the glass transition temperature of photodegraded EPDM and EPDM/MWCNT nanocomposites. POLYM. COMPOS., 30:855-860, 2009. (C) 2008 Society of Plastics Engineers</p>1 aKumar, Bijandra1 aKumar, Indresh1 aSingh, R., P.  uhttps://library.ncl.res.in/content/photodegradation-epdmmwcnt-nanocomposites-effect-singlet-oxygen-002692nas a2200241   4500008004100000022001400041245011600055210006900171260009900240300001400339490000700353520173200360653002902092653004302121653003302164100002202197700002902219700001602248700002002264700002402284700001802308856012402326       2009                        eng d  a0032-386100aPreparation and nonisothermal crystallization behavior of polypropylene/layered double hydroxide nanocomposites0 aPreparation and nonisothermal crystallization behavior of polypr  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcMAR  a1505-15150 v503 a<p>Polypropylene (PP)/layered double hydroxide (LDH) nanocomposites were prepared via melt intercalation using dodecyl sulfate anion modified LDH and maleated PP as compatibilizing agent. Evidently the interlayer anions in LDH galleries react with maleic anhydride groups of PP-g-MA and lead to a finer dispersion of individual LDH layers in the PP matrix. The nanostructure was characterized by XRD and TEM; the examinations confirmed the nanocomposite formation with exfoliated/intercalated layered double hydroxides well distributed in the PP matrix. The nonisothermal crystallization behavior of resulting nanocomposites was extensively studied using differential scanning calorimetry (DSC) technique at various cooling rates. In nonisothermal crystallization kinetics, the Ozawa approach failed to describe the crystallization behavior of nanocomposites, whereas the Avrami analysis and Jeziorny method well define the crystallization behavior of PP/LDH nanocomposite. Combined Avrami and Ozawa analysis (Liu model) also found useful. The results revealed that very small amounts of LDH (1%) could accelerate the crystallization process relative to the pure PP and increase in the crystallization rates was attributed to the nucleating effect of the nanoparticles. Polarized optical microscopy (POM) observations also support the DSC results. The effective crystallization activation energy was estimated as a function of the relative degree of crystallinity using the isoconversional analysis. Overall, results indicated that the LDH particles in nanometer size might act as nucleating agent and distinctly change the type of nucleation, growth and geometry of PP crystals. (C) 2009 Elsevier Ltd. All rights reserved.</p>10aLayered double hydroxide10aNonisothermal crystallization kinetics10aPolypropylene nanocomposites1 aLonkar, Sunil, P.1 aMorlat-Therias, Sandrine1 aCaperaa, N.1 aLeroux, Fabrice1 aGardette, Jean, Luc1 aSingh, R., P.  uhttps://library.ncl.res.in/content/preparation-and-nonisothermal-crystallization-behavior-polypropylenelayered-double-001726nas a2200217   4500008004100000022001400041245009100055210006900146260007500215300001200290490000700302520092900309653001901238653003401257653002001291653001601311653001801327100002601345700001801371856011901389       2010                        eng d  a1566-254300aEffect of gamma-dose rate on biodegradation of gamma-sterilized biomedical polyolefins0 aEffect of gammadose rate on biodegradation of gammasterilized bi  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScDEC  a600-6070 v183 a<p>The aim of the present study is to study the effect of gamma-dose rate on the biodegradation of gamma-sterilized polyolefins. Films of isotactic polypropylene, high density polyethylene and ethylene-propylene (EP) copolymer were sterilized under gamma-radiation with doses of 10 and 25 kGy. Two different (60)Co sources were used with dose rate 600 and 780 Gy h(-1). Neat and sterilized samples were incubated in compost and fungal culture environments. The changes in functional groups, surface morphology and intrinsic viscosity in polymer chains were characterized by FT-IR spectroscopy, SEM and viscometric measurements, respectively. It was observed that both gamma-degradation and biodegradation processes depend on the dose rate of gamma-source. It was found that the biodegradation of gamma-sterilized polyolefins in composting and microbial culture environments increased with decreasing the gamma-dose rate.</p>10aBiodegradation10aComposting and fungal culture10agamma-Dose rate10aPolyolefins10aSterilization1 aAlariqi, Sameh, A. S.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/effect-gamma-dose-rate-biodegradation-gamma-sterilized-biomedical-polyolefins-001945nas a2200217   4500008004100000022001400041245009800055210006900153260008000222300001000302490000700312520112900319653003701448653001401485653002201499653001801521100002601539700001801565700001901583856012501602       2011                        eng d  a1319-802500aGamma-initiated oxidation of isotactic polypropylene: effect of gamma-dose rate on durability0 aGammainitiated oxidation of isotactic polypropylene effect of ga  aTIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANYbSPRINGER HEIDELBERGcJAN  a29-380 v363 a<p>The effect of gamma-irradiation dose rate on the chemical, molecular, and mechanical properties of isotactic polypropylene (iPP) films was investigated using three different Co-60 sources with dose rates of 600, 660, and 780 Gy h(-1). Fourier transform infrared spectroscopy coupled with chemical derivatization with NO and SF4, and measurements of the elongation at break, toughness, and molecular weight were used to describe the effects of gamma-dose rate on iPP. It was found that the formation of oxidation products depended significantly on the dose rate. However, the kinetic accumulation of ketones were more sensitive to the dose rate of gamma source. Degradation induced by gamma-radiation depends on the dose rate-the degradation of mechanical properties was more significant at a low dose rate than at a high dose rate. It was found that the lower the dose rate, the higher the degree of oxidation in terms of the formation of gamma-products. The mechanism of gamma-degradation is discussed based on the correlation between the changes in chemical and physical properties upon exposure to gamma-radiation.</p>10aChemical and physical properties10aDose rate10agamma-irradiation10apolypropylene1 aAlariqi, Sameh, A. S.1 aSingh, R., P.1 aRao, B., S. M.  uhttps://library.ncl.res.in/content/gamma-initiated-oxidation-isotactic-polypropylene-effect-gamma-dose-rate-durability-002026nas a2200301   4500008004100000022001400041245012800055210006900183260006700252300001400319490000700333520095100340653002301291653002701314653002201341653003101363653001601394653003101410100002401441700001801465700001701483700002201500700002201522700001801544700002301562700002201585856011701607       2011                        eng d  a1042-714700aStudies on the feasibility of recycled polystyrene doped with NLO active meta-Nitroaniline for optoelectronics applications0 aStudies on the feasibility of recycled polystyrene doped with NL  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcDEC  a1865-18710 v223 a<p>A Guest-Host system based on meta-Nitroaniline (m-NA) and recycled polystyrene (RPS) susceptible to generate nonlinear optically (NLO) active property such as second harmonic generation (SHG) has been prepared. Pure, sublimed, optical grade, crystalline m-NA is used as a guest and RPS from the disposable packaging waste as available utilized as the host polymer. In this paper we report the effect of NLO active m-NA on the bulk and optical properties of RPS. The purified m-NA was incorporated from 1-10 wt% in the RPS polymer matrix by conventional solution casting method. Thin, transparent, freestanding films obtained were characterized with optical microscope, scanning electron microscope (SEM), viscosity measurement, and UV-Visible (UV-Vis) spectroscopy for bulk properties evaluation and Nd:YAG laser studies for optoelectronics application such as SHG through frequency doubling. Copyright (C) 2010 John Wiley &amp; Sons, Ltd.</p>10afrequency doubling10aguest-host NLO systems10ameta-Nitroaniline10anonlinear optical activity10aPolystyrene10asecond harmonic generation1 aSureshkumar, M., S.1 aGoyal, R., K.1 aNegi, Y., S.1 aPratheepkumar, A.1 aReddy, Raghunatha1 aSingh, R., P.1 aDadge, Jagdish, W.1 aAiyer, Rohini, C.  uhttps://library.ncl.res.in/content/studies-feasibility-recycled-polystyrene-doped-nlo-active-meta-nitroaniline-001985nas a2200193   4500008004100000022001400041245006600055210006400121260011000185300001600295490000600311520126600317100002201583700002401605700002301629700001901652700001801671856010201689       2012                        eng d  a2046-206900aSelf photostabilizing UV-durable MWCNT/polymer nanocomposites0 aSelf photostabilizing UVdurable MWCNTpolymer nanocomposites  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT  a12255-122620 v23 a<p>A potentially active hindered amine light stabilizer (HALS) was successfully anchored onto multiwalled carbon nanotubes (MWCNTs) and used as a light-stabilizing yet reinforcing multifunctional nanofiller to obtain UV-durable polymer nanocomposites. The influence of such light stabilizing MWCNTs on the photo-oxidation behaviour and structure-properties of polypropylene (PP) was studied. The composites were prepared by solution mixing of MWCNTs followed by melt compounding with polypropylene (PP). The resulting composite exhibits excellent UV-durability showing an almost 20 fold increase in the induction period of photo-oxidation. Moreover, the hydrophobic HALS was found to be compatibilizing enough to achieve homogeneous dispersion of exfoliated nanotubes into a polymer matrix. The rheological characterizations predict the formation of a percolated network structure. The obtained nanocomposites present markedly improved mechanical properties which underline the reinforcing ability of functionalized MWCNTs. Overall combination of HALS and MWCNTs offers an attractive route to combine multifunctionality into new hybrid UV-durable polymer nanocomposites. Such materials may possess great potential for outdoors high performance applications.</p>1 aLonkar, Sunil, P.1 aKushwaha, Omkar, S.1 aLeuteritz, Andreas1 aHeinrich, Gert1 aSingh, R., P.  uhttps://library.ncl.res.in/content/self-photostabilizing-uv-durable-mwcntpolymer-nanocomposites-001715nas a2200169   4500008004100000022001400041245012700055210006900182260006700251300001200318490000700330520101800337100002301355700002201378700001801400856012701418       2012                        eng d  a1083-560100aSynthesis and characterization of a new diol-functionalized s-triazine-based polymerizable hindered amine light stabilizer0 aSynthesis and characterization of a new diolfunctionalized stria  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcSEP  a204-2080 v183 a<p>A new diol-functionalized triazine-based polymerizable hindered amine light stabilizer (HALS) was synthesized in two steps. First, selective synthesis of an s-triazine containing two HALS moieties as substituents was accomplished by using phase-transfer catalysis. This step required the establishment of optimum reaction conditions (type of two-phase system, best solvent, and catalyst). In the second step, the substituted triazine was treated with diethanolamine to introduce polymerizable diol functionality. The resulting product should act as a light stabilizer, since it contains two HALS moieties anchored to a thermally stable s-triazine unit. Moreover, incorporation of the diol into a polymeric material might be expected to impart prolonged stability in weathering environments. Characterization of the diol was accomplished by using Fourier transform infrared spectroscopy (FTIR), `H NMR, and mass spectrometry. J. VINYL ADDIT. TECHNOL., 18:204208, 2012. (c) 2012 Society of Plastics Engineers</p>1 aMehare, Rupali, S.1 aLonkar, Sunil, P.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/synthesis-and-characterization-new-diol-functionalized-s-triazine-based-polymerizable-002067nas a2200277   4500008004100000022001400041245017900055210006900234260006700303300001400370490000800384520105500392653001101447653001501458653001601473653001301489100001601502700002601518700001801544700002101562700001801583700001701601700002101618700002301639856012701662       2013                        eng d  a0021-899500aCopolymerization of ethylene with unsaturated alcohols and methylmethacrylate using a silylated alpha-diimine nickel catalyst: molecular modeling and photodegradation studies0 aCopolymerization of ethylene with unsaturated alcohols and methy  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcAUG  a1820-18320 v1293 a<p>In this article, the experimental results obtained in the copolymerization of ethylene with polar monomers using a silylated -diimine nickel catalyst are described and compared with those obtained with a non-silylate similar one. The results show that the introduction of a siliyl group in the para-position of the imine moiety turns the catalyst less sensitive toward polar functionalities. However, the reactivity observed in copolymerization reactions was found to be reduced both the global polymerization and incorporation rates. Molecular modeling calculation allowed us to understand both the preferred insertion mode and the intermediate product structures for E/MMA copolymerization. Photodegradation studies showed that the presence of polar groups in the copolymers increases their rate of oxidation and turn them more easily degradable. The stabilization performed by Tinuvin 770 showed that for long-exposure times, it is not very effective regardless it is only mixed or grafted to the copolymer. (c) 2012 Wiley Periodicals, Inc.</p>10aageing10acopolymers10aDegradation10agrafting1 aMatos, Ines1 aFernandes, Susete, N.1 aLiu, Hua-Rong1 aTevtia, Amit, K.1 aSingh, R., P.1 aManda, Lemos1 aLemos, Francisco1 aMarques, Maria, M.  uhttps://library.ncl.res.in/content/copolymerization-ethylene-unsaturated-alcohols-and-methylmethacrylate-using-silylated-002305nas a2200241   4500008004100000022001400041245012500055210006900180260009900249300001200348490000800360520133900368653003001707653001301737653003001750653004401780653002301824653002901847100002401876700002101900700001801921856012401939       2015                        eng d  a0144-861700aPreparation and characterization of self-photostabilizing UV-durable bionanocomposite membranes for outdoor applications0 aPreparation and characterization of selfphotostabilizing UVdurab  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcJUN  a164-1730 v1233 a<p>Here, we report a durable and ultraviolet (UV) resistant nanocomposite membrane of chitosan (CS) with effective photostabilization ascribed to Zinc oxide (ZnO) nanoparticles. Zinc oxide nanoparticles were successfully dispersed in the solution of chitosan polymer. The nanocomposite films with the homogenous dispersion of ZnO nanoparticles in the chitosan matrix were obtained by solution casting method and the influence of ZnO nanoparticles as a photostabilizer was studied. The nanocomposite membranes were photoirradiated by polychromatic radiations with lambda &gt; 300 nm using mercury vapour lamps in SEPAP instrument. The resulting nanocomposite material exhibited excellent UV-resistance in very low percentages of ZnO nanoparticles. The chitosan membranes showed fast degradation attributes than the nanocomposite membranes. ZnO nanoparticles effectively absorbed UV radiations, thus protecting polymer from radiation degradation. The neat and irradiated nanocomposites of chitosan and ZnO nanoparticles (CS/ZnO) were characterized by Fourier Transform Infrared Spectroscopy (FT-IR) spectroscopy for the chemical changes/degradation taking place. Chitosan nanocomposites were further characterized for tensile properties, contact angle measurements and surface morphology. (C) 2015 Elsevier Ltd. All rights reserved.</p>10aBionanocomposite membrane10aChitosan10aContact angle measurement10aFourier transform infrared spectroscopy10aPhotostabilization10aZinc oxide nanoparticles1 aKushwaha, Omkar, S.1 aAvadhani, C., V.1 aSingh, R., P.  uhttps://library.ncl.res.in/content/preparation-and-characterization-self-photostabilizing-uv-durable-bionanocomposite-0