Search results for "Degradation reaction"

showing 2 items of 2 documents

The role of crystalline, mobile amorphous and rigid amorphous fractions in the performance of recycled poly (ethylene terephthalate) (PET)

2012

[EN] The action of thermo-mechanical degradation induced by mechanical recycling of poly(ethylene terephthalate) was simulated by successive injection moulding cycles. Degradation reactions provoked chain scissions and a reduction in molar mass mainly driven by the reduction of diethyleneglycol to ethylene glycol units in the flexible domain of the PET backbone, and the formation of -OH terminated species with shorter chain length. The consequent microstructural changes were quantified taking into account a three-fraction model involving crystalline, mobile amorphous (MAF) and rigid amorphous fractions (RAF). A remarkable increase of RAF, to a detriment of MAF was observed, while the percen…

EthyleneSolucions polimèriquesPolymers and PlasticsInjection mouldingDifferential scanning calorimetry (DSC)Crystalline fractionsMechanical propertiesThermo-mechanical degradationchemistry.chemical_compoundDegradationAmorphous materialsPolymer blendsMaterials ChemistryMechanical recyclingRecyclingComposite materialDiethyleneglycolPoly(ethylene terephthalate) (PET)Injection moldingMolar massMechanical featureRecycled poly(ethylene terephthalate)Microstructural changesCondensed Matter PhysicsChain scissionRigid-amorphous fractionMechanics of MaterialsMAQUINAS Y MOTORES TERMICOSPolymer blendMaterials scienceMechanical performanceViscoelasticityEthyleneDifferential scanning calorimetrySegmental dynamicsInfrared analysis (FT-IR)Degradation reactionDifferential scanning calorimetryInjection mouldingPolyethylene terephthalatesEthylene glycolTermoplàsticsCrystalline materialsShorter chainsAmorphous solidchemistryGlass-rubber relaxationProcessing cyclesEthylene glycol
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One-pot synthesis of ZnO nanoparticles supported on halloysite nanotubes for catalytic applications

2020

Abstract A versatile catalyst based on halloysite and zinc oxide (HNT@ZnO) was prepared, for the first time, starting from ZnO commercial bulk form as Zn precursor source, in a one-pot procedure. This strategy gives the possibility to obtain small ZnO nanoparticles loaded on the HNT surface without the use of inorganic salts which envisage the removal of undesired anions and therefore a calcination process at high temperature. It was found that the presence of halloysite improved the UV–vis spectral absorption ability of ZnO. The hybrid was successful used as photocatalyst for the methylorange and rhodamine B degradation. In addition, after eight consecutive cycles for the methylorange phot…

Materials scienceOne-pot synthesisNanoparticle020101 civil engineering02 engineering and technologyengineering.material7. Clean energyHalloysite0201 civil engineeringCatalysislaw.inventionchemistry.chemical_compoundGeochemistry and PetrologylawRhodamine BCalcinationPhotodegradationHalloysite nanotubes Zinc oxide Heterogeneous catalyst Photodegradation reaction Biodiesel productionGeologySettore CHIM/06 - Chimica Organica021001 nanoscience & nanotechnologyChemical engineeringchemistryengineeringPhotocatalysis0210 nano-technologyApplied Clay Science
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