Sökning: "hydroxyethyl cellulose"
Visar resultat 16 - 20 av 31 avhandlingar innehållade orden hydroxyethyl cellulose.
16. Surfactant Responsive Cross-Linked Polymer Hydrogels
Sammanfattning : The focus of the thesis is on chemically cross-linked hydrogels which drastically change their volume when immersed in solutions of different ionic surfactants (with or without added salt). The two main questions addressed are: (1) How useful are simple gel swelling experiments to the study of polymer-surfactant interactions?, and (2) How does the volume of a cross-linked polymer gel change when it is immersed in a surfactant solution, both with respect to the equilibrium swelling and with respect to transient volume changes? Most of the gels studied were prepared by cross-linking linear polymers, which were well studied derivatives of hydroxyethyl cellulose (HEC). LÄS MER
17. Surface nanomechanical properties of hydrogels and coatings
Sammanfattning : Characterizing mechanical and wear properties at the nanometer scale emerged as a fascinating and challenging topic in the last decades due to recognition of many interesting and unusual properties of nanomaterials. Due to recent developments of the atomic force microscopy (AFM) technique, it is now possible to measure nanomechanical properties and topography simultaneously, as well as performing and evaluating wear measurements at the nanometer scale. LÄS MER
18. Hydrophobically Modified Polymers. Rheology and Molecular Associations
Sammanfattning : Structure- property relationships and thickening mechanism in aqueous solution of two hydrophobically modified polymers (HM-P) with different architecture have been investigated. The two polymers, hydrophobically modified ethyl hydroxyethyl cellulose (HM-EHEC) and hydrophobically modified polyethylene glycol (HM-PEG), are commonly used as associative thickeners in the paint industry. LÄS MER
19. Isolation, characterization and enzymatic hydrolysis of water-soluble wood polysaccharides
Sammanfattning : The need for new renewable products has enhanced the interest in cellulose and hemicellulose as raw material. The wood plant cell wall is a complex mixture of cellulose, hemicellulose, lignin and minor amounts of pectin, proteins and extractives. Several interactions between the compounds make them difficult to separate without modification. LÄS MER
20. Complex Macromolecular Architectures by Atom Transfer Radical Polymerization
Sammanfattning : Controlled radical polymerization has proven to be a viableroute to obtain polymers with narrow polydispersities (PDI's)and controlled molecular weights under simple reactionconditions. It also offers control over the chain-]ends of thesynthesized polymer. LÄS MER