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Showing result 1 - 5 of 15 swedish dissertations matching the above criteria.

  1. 1. Controlling Polylactide Degradation through Stereocomplexation and Lactic Acid Based Additives

    Author : Sofia Regnell Andersson; Minna Hakkarainen; Ann-Christine Albertsson; Marek Kowalczuk; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Polylactide; stereocomplex; plasticizer; degradation; degradation products; ESI-MS;

    Abstract : The successful use of degradable materials in new applications depends on our ability to control the degradation process. A number of aspects need to be evaluated including degradation rate, the onset of degradation and the nature, formation and release of degradation products. READ MORE

  2. 2. Levulinic Acid : Versatile Building Block for Plasticizer Design

    Author : Wenxiang Xuan; Minna Hakkarainen; Karin Odelius; Rafael Auras; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; levulinic acid; plasticizer; polylactide; migration; degradation; antibacterial;

    Abstract : The utilization of renewable resources is a challenging and an importantaspect towards development of sustainable plastic products. Therefore,commercial biomass conversion to produce biobased chemicals isnecessary to replace current fossil-based chemicals. READ MORE

  3. 3. Tuning the polylactide hydrolysis rate without introducing new migrants

    Author : Sofia Regnell Andersson; Minna Hakkarainen; Karin Jacobson; Ulrika Edlund; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; polylactide; sterocomplex; plasticizer; degradation; degradation products; ESI-MS; Biochemistry; Biokemi; Polymer chemistry; Polymerkemi;

    Abstract : The possibility to control and tune the hydrolytic degradation rate of polylactide without introducing any new degradation products was investigated by subjecting polylactide with cyclic or linear oligolactic acid additives, and a stereocomplex between the L- and D-enantiomers of polylactide to hydrolytic degradation at 37 and 60 °C for up to 39 weeks. The degradation was monitored by measuring mass loss, molar mass changes, water uptake, changes of surface structure, crystallinity and thermal properties. READ MORE

  4. 4. Poly (butylene succinate) and poly (butylene adipate) : quantitative determination of degradation products and application as PVC plasticizers

    Author : Annika Lindström; Minna Hakkarainen; Ann-Christine Albertsson; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; solid phase extraction; degradation products; poly butylene succinate ; poly butylene adipate ; GC-MS; PVC; plasticizer; Biokemi; Biochemistry; Biokemi;

    Abstract : A solid phase extraction (SPE) method was developed for simultaneous extraction of dicarboxylic acids and diols formed during hydrolysis of poly(butylene succinate), PBS, and poly(butylene adipate), PBA. The developed SPE method and subsequent GC-MS analysis were used to extract, identify and quantify low molecular weight products migrating from linear and branched poly(butylene adipate) (PBA) and poly(butylene succinate) (PBS) during aging in aqueous media. READ MORE

  5. 5. Long-term Performance of PVC and CSPE Cables used in Nuclear Power Plants : the Effect of Degradation and Plasticizer migration

    Author : Maria Ekelund; Ulf Gedde; Thomas Hjertberg; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; PCV; CSPE; cables; ageing; mechanical properties; plasticizer migratio; LIRA; life time prediction; Chemistry; Kemi;

    Abstract : Enormous amounts of low voltage cables installed in a Swedish nuclear power plant are reaching their expected lifetimes. Since the cables are crucial to operational safety, it is of great importance that the actual condition of the installed cables is determined. READ MORE