Sökning: "vinyl ester"

Visar resultat 6 - 10 av 29 avhandlingar innehållade orden vinyl ester.

1. 6. Environmentally Friendly Plasticizers for PVC : Improved Material Properties and Long-term Performance Through Plasticizer Design

   Författare :Annika Lindström; Minna Hakkaraninen; Anders Södergård; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; poly butylene adipate ; poly vinyl chloride ; plasticizers; miscibility; mechanical properties; surface segregation; migration; degradation products; Polymer chemistry; Polymerkemi;

   Sammanfattning : Linear and branched poly(butylene adipate) polyesters with number-average molecular weights ranging from 700 to 10 000 g/mol, and degrees of branching ranging from very low to hyperbranched were solution cast with PVC to study the effects of chemical structure, molecular weight, end-group functionality, and chain architecture on plasticizing efficiency and durability. Miscibility was evaluated by the existence of a single glass transition temperature and a shift of the carbonyl group absorption band. LÄS MER

3. 7. Design and stereoselective syntheses of Phe-Phe dipeptidomimetics

   Författare :Annika Jenmalm Jensen; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutical biosciences; Farmaceutisk biovetenskap; Biopharmacy; Biofarmaci; Organic Pharmaceutical Chemistry; organisk farmaceutisk kemi;

   Sammanfattning : Several stereochemically well characterized Phe-Phe dipeptidomimetics have been designed and synthesized. The Phe-Phe vinyl isostere was used as a key intermediate. The synthesized series of mimetics includes two isomeric epoxides, four 1,2-dihydroxyethylene isomers, two isomeric allylic alcohols and two isomeric allylic fluorides. LÄS MER

4. 8. Influence of liquid diffusion on the performance of polymer materials in industrial applications

   Författare :Stefanie Römhild; Mikael Hedenqvist; Lars Berglund; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LCP; Vectra A950; thermoset resin; FRP; diffusion; disclination; annealing; lining; bonding; long-term properties in water; Polymer chemistry; Polymerkemi;

   Sammanfattning : Diffusion of liquids into and through polymers is an important factor that negatively may influence the durability or lifetime of a polymer structure used in industrial applications. In this work two types of polymers, a liquid crystalline polymer (LCP, Vectra A950) and various thermoset resins as used in fibre reinforced plastics (FRP) process equipment were studied with regard to barrier properties, chemical resistance and long-term performance. LÄS MER

5. 9. Thermal Degradation and Adhesion Studies of Ethylene Copolymers

   Författare :Bernt-Åke Sultan; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The thermal stability of ethylene(vinyl acetate) (EVA), ethylene(n-butyl acrylate) (EBA), ethylene(vinyl trimethoxy silane) (EVS) and ethylene(vinyl trimetoxy, butylacrylate) (EVSBA) copolymers have been mapped out in this study. The different ester groups', i.e. LÄS MER

7. 10. An Investigation of Peroxidase Activity in Biomimetic and Biological Systems

   Författare :Ekaterina Ryabova; Kemiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; metabolism; Metabolism; enzymologi; Proteiner; enzymology; Proteins; hemoglobin; catalysis; peptide; peroxidase; protoporphyrin IX; Biokemi; Biochemistry;

   Sammanfattning : In order to create a heme environment which permits biomimicry of heme-containing plant peroxidases and investigate the role played by the vinyl side chains of the porphyrin ring on the stability and, possibly, catalytic activity of model compounds, a number of new synthetic microperoxidases -– hemin-6(7)-gly-his methyl ester (HGH) and hemin-6(7)-gly-gly-his methyl ester (HGGH) and hemin-6,7-bis(gly-gly-his methyl ester) (H2GGH) as well as mesohemin-6(7)-gly-gly-his methyl ester (MGGH) and deuterohemin-6(7)-gly-gly-his methyl ester (DGGH) have been prepared by condensation of a peptide residue with the propionic side chains of hemin, mesohemin and deuterohemin, respectively. Reactivity studies towards different organic and inorganic substrates showed that not only five- but also six-coordinate hemin peptide complexes catalyze the oxidation of substrates by H2O2. LÄS MER