The influence of thermal treatment on the hierarchical structure of HDPE in GAIM Student: Shan He Surpervisor: Mingbo Yang 2015-1-10Melt fillingGas delay timeGas injectionGas-assisted packingDemoldingGAIM cycle Advantagesl clamping tonnagel cycle timel material consumptionl etcBackgroundBackgroundProcess parameter l delay timel mold temperturel melting temperturel gas pressure(a)(b)(c)(d)Schematic representation for the classification of HDPE parts: (a) skin layer; (b) sub-skin layer; (c) intermediate layer; and (d) gas channel zone 1 Materiall polymer/polymer blendsPC/PE PA/PE HDPE/HDPE HDPE/LLDPE Backgroundl polymer/filler blendsGF/PA GF/PP HDPE/MWCNTl Single component polymerMolecular weight distributionLong chain branchRadiation cross-linkingExprimentsGAIMGAIMThermal treatment(280,2.5h,5h,10h)HDPEMelt temperature () 210Mold temperature () 40Shot size (%)80Gas pressure (MPa)10.4Gas delay time (s)1Gas injection time (s)20Table .1 Processing parameters of the GAIM processesResults and disscusionsionFTIRXRDSSAResults and disscusionsionResults and disscusionsionDSCResults and disscusionsion(a)(b)(c)Rheological property (a)5mshish-kebab5m(b)shish-kebab5m(c)Oriented lamella(d)5mSpheruliteNeat60982.5H5mshish-kebab(a)5mshish-kebab(b)5mOriented lamellaSpherulite(c)5mOriented lamellaSpherulite(d)Results and disscusionsion10H5H5m(b)shish-kebab5m(a)shish-kebab(c)5mshish-kebab(d)5mOriented lamella5m(a)shish-kebab5m(b)shish-kebab5m(c)Oriented lamella5m(d)Oriented lamellaResults and disscusionsionResults and disscusionsionTensile testHypothetical mechanism Thermal treating can reduce the contents of short chain branch(SCB) in HDPE.With the reduce of the contents of SCB,the HDPE samples perform better oriented crystalline stucture as well as tensile property.Thank you !