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1	Methacrylic Copolymers for Controlled Phase Separation and Complex Coacervation Jones, Janevieve Agatha 12 1900 (has links) <p> It is well known that complex coacervates can be prepared by combining aqueous solutions of oppositely charged biopolymers, such as gelatin and gum arabic. There are few examples of synthetic polyelectrolytes that produce complex coacervates, however. Two series of anionic copolymers capable of forming complex coacervates with branched polyethylenimine (PEI) in water have been prepared. One series consists of binary copolymers containing methacrylic acid (MAA) and poly(ethylene glycol) monomethyl ether monomethacrylate (PEGMA) in molar ratios ranging from 20:80 to 80:20, as well as the two homopolymers, poly(MAA) and poly(PEGMA). Another series contains an equimolar amount of MAA and PEGMA, together with between one and ten percent of a third, hydrophobic monomer, butyl methacrylate (BMA).</p> <p> Both binary and ternary copolymers show lower critical solution temperatures, LCST's, ranging from 60.8°C to 1.5°C depending on composition. Furthermore, complex coacervation occurs upon addition of aqueous PEI to aqueous solutions of these copolymers. The percent volume of the liquid coacervate phase is independent of copolymer composition. However, with increasing MAA to PEGMA ratio in the binary copolymer, the concentration of the coacervate increases, reflecting an increased coacervation efficiency. The coacervate composition was not significantly affected by the BMA in the ternary copolymer series.</p> / Thesis / Master of Science (MSc)
2	Wettability of Methacrylate Copolymer Films Deposited on Anodically Oxidized and Roughened Aluminium Surfaces Frenzel, Ralf, Blank, Christa, Grundke, Karina, Hein, Veneta, Schmidt, Bernd, Simon, Frank, Thieme, Michael, Worch, Hartmut 18 March 2013 (has links) (PDF) The wetting behavior of water on methacrylate copolymer films was studied on anodically oxidized and micro-roughened aluminium surfaces and also on smooth model surfaces. The copolymerization of tert-butyl methacrylate with a methacrylate containing a fluoroorganic side chain led to a considerable decrease of the surface free energy, but not to a superhydrophobic behavior of polymer-coated, micro-roughened aluminium surfaces. However, copolymers containing both hydrophobic and hydrophilic sequences are able to form superhydrophobic films. X-ray photoelectron spectroscopy showed that an enrichment of the interface between the solid phase and the air by fluorine-containing polymer components was the reason for the strong decrease of the surface free energy. The hydrophilic segments of the copolymers improved the ability to wet the highly polar aluminium surface and to form films of higher density. Methacrylsäure-Copolymere Mischpolymere Benetzungsverhalten Superhydrophobie Aluminium Aufrauhen Beschichtung Oberflächensegregation Röntgenphotoelektronenspektroskopie Methacrylic copolymers wetting behavior superhydrophobicity aluminium roughening coating XPS surface segregation X-ray Photoelectron Spectroscopy ddc:620 rvk:UV 7100
3	Wettability of Methacrylate Copolymer Films Deposited on Anodically Oxidized and Roughened Aluminium Surfaces Frenzel, Ralf, Blank, Christa, Grundke, Karina, Hein, Veneta, Schmidt, Bernd, Simon, Frank, Thieme, Michael, Worch, Hartmut January 2009 (has links) The wetting behavior of water on methacrylate copolymer films was studied on anodically oxidized and micro-roughened aluminium surfaces and also on smooth model surfaces. The copolymerization of tert-butyl methacrylate with a methacrylate containing a fluoroorganic side chain led to a considerable decrease of the surface free energy, but not to a superhydrophobic behavior of polymer-coated, micro-roughened aluminium surfaces. However, copolymers containing both hydrophobic and hydrophilic sequences are able to form superhydrophobic films. X-ray photoelectron spectroscopy showed that an enrichment of the interface between the solid phase and the air by fluorine-containing polymer components was the reason for the strong decrease of the surface free energy. The hydrophilic segments of the copolymers improved the ability to wet the highly polar aluminium surface and to form films of higher density. info:eu-repo/classification/ddc/620 ddc:620

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