Search for dissertations about: "polyethylene degradation"

Showing result 1 - 5 of 47 swedish dissertations containing the words polyethylene degradation.

  2. 1. Environmentally Degradable Polyethylene : Effects of Additives and Environment on the Degradation and Degradation products

    Author : Farideh Khabbaz; KTH; []
    Keywords : LDPE; polyethylene; oxidative degradation; photo-oxidation; thermo-oxidation; degradation products; photosensitisers; pro-oxidant; starch; master-batch; gas chromatography mass-spectrometry; GC-MS; solid phase microextraction; SPME;

    Abstract : This thesis summarises and compares the influences ofdifferent additives (photosensitisers, pro-oxidants, abiodegradable filler) on blown low-density polyethylene (LDPE)films during photo- and thermal degradation with respect tochemical changes in the polymer matrices and identifieddegradation products. Additives studied were irondimethyldithiocarbamate (FeDMC), nickel dibutyldithocarbamate(NiDBC), carbon black, starch, a pro-oxidant that consisted ofmanganese stearate together with styrene butadiene rubber (SBR)or natural rubber (NR) and a master batch containing linearLDPE, starch and pro-oxidant. READ MORE

  4. 2. Degradation of polyethylene pipes distributing chlorinated water : depletion of stabilizers, release of degraded products and polymer degradation

    Author : Wenbin Yu; Ulf Gedde; Mats Jonsson; Minna Hakkarainen; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; polyethylene pipes; chlorine dioxide; degradation; Polymer chemistry; Polymerkemi;

    Abstract : This thesis presents the study of antioxidants depletions in chlorinated media (10 ppm Cl2 - and ClO2 - aqueous media), polyethylene pipes degradations scenarios and migration of the degraded species to aqueous phase. Pressure testing on pipes and squalane testing with controlled pH aqueous media (6.8 ± 0. READ MORE

  5. 3. Oxidative Degradation of Polyethylene - A Cause of Off-flavour

    Author : Thorbjörn Andersson; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biopolymers; Polymerteknik; Polymer technology; off-flavour; degradation; polyethylene;

    Abstract : Polyethylene is the most frequently used polymer material in food packaging today. The polymer is often processed by film extrusion and extrusion coating between 250°C and 325°C. READ MORE

  6. 4. Deterioration of Polyethylene Exposed to Chlorinated Species in Aqueous Phases : Test Methods, Antioxidants Consumption and Polymer Degradation

    Author : Wenbin Yu; Ulf Gedde; Sahar Al-Malaika; KTH; []
    Keywords : Antioxidants; Polyethylene pipes; Chlorine dioxide; Degradation;

    Abstract : This thesis presents a study of antioxidant depletion in water containing chlorinated species (water containing 10 ppm either Cl2 or ClO2, buffered to pH = 6.8), the degradation products in the aqueous phase, and polyethylene pipe degradation scenarios. READ MORE

  7. 5. Material recycling of post-consumer flexible polyethylene packaging waste

    Author : Ezgi Ceren Boz Noyan; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; degradation; polyethylene; melt-compounding; washing; post-consumer flexible packaging waste; mechanical properties; plastics recycling;

    Abstract : The mechanical and thermal properties of recycled post-consumer flexible polyethylene packaging waste was studied, using material collected and sorted on a large-scale from two sources. Unwashed, laboratory-scale washed, industrial-scale washed, and industrial-scale washed and melt-compounded (industrially recycled) materials were used. READ MORE