简介：INTRODUCTIONPolyhydroxybutyrate(PHB)andit'scopolymerPHBVachievedbythebiosyntheticpathway,hasattractedmuchattentionasanalternationbiodegradablematerials.Theyhavetheexcellentbiocompatibilityandproperdegradationperiodsbyoptimizationofpertinentmolecularweightandcopolymercompositions.

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简介：Poly(etherurethane)s(PEU),includingPEUI15andPEUH15,werepreparedthroughchain-extensionreactionofpoly(ethyleneglycol)(PEG-1500)usingdiisocyanateasachainextender,includingisophoronediisocyanate(IPDI)andhexamethylenediisocyanate(HDI).ThesePEUswereusedtotoughenpolylactide(PLA)byphysicalandreactiveblending.Thermal,morphological,mechanicalandagingpropertiesoftheblendswereinvestigatedindetail.ThesePEUswerepartiallycompatiblewithPLA.Theelongationatbreakofthereactiveblendsinthepresenceoftriphenylphosphate(TPP)forPLAwithPEUH15orPEUI15wasmuchhigherthanthatofthephysicalblends.Theagingtestwascarriedoutat-20°Cfor50hinordertoacceleratethecrystallizationofPEUs.ThePEUsinthePLA/PEUblendsproducedcrystallizationandformednewphaseseparationwithPLA,resultinginthedeclinedtoughnessofblends.Fortunately,undertheagingcondition,althoughPEUH15inblendscouldalsoformcrystallization,thereactiveblendofPLA/PEUH15/TPP(80/20/2)hadhighertoughnessthantheotherblends.TheelongationatbreakofPLA/PEUH15/TPP(80/20/2)droppedto287%fortheagingblendfrom350%fortheoriginalblend.ThetensilestrengthandmodulusofPLA/PEUH15/TPPblenddidnotchangeobviouslybecauseofthecrystallizationofPEUH15.