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Owen M.J.,Michigan Molecular Institute
Silicon | Year: 2014

Polydimethylsiloxane (PDMS), the most familiar silicone polymer, is a very water repellent material. Its hydrophobicity is not markedly less than many fluorine containing polymers. The original purpose of introducing fluorine into silicones in the form of polymethyltrifluoropropylsiloxane (PMTFPS) was not to seek enhanced water repellency but to provide improved resistance to organic oils and solvents. Because of the two methyl groups on each silicon atom in PDMS, the resultant oleophilicity is a considerable drawback in applications involving exposure to hydrocarbon fluids and oils. In this article we survey the contact angles with water and n-hexadecane of these polymers and related, more highly fluorinated fluorosilicones, being the simplest measure of their hydrophobicity and oleophilicity, respectively. These contact angle values provide quantitative insight into commercially valuable aspects of silicone surface science. © 2014 Springer Science+Business Media Dordrecht.

Owen M.J.,Michigan Molecular Institute
ACS Symposium Series | Year: 2010

Uses that relate to surface properties dominate the silicone industry. Since only aliphatic fluorocarbon-based materials have lower surface energies than conventional silicones such as polydimethylsiloxane (PDMS), it can be expected that fluorocarbon-modified silicones, i.e. fluorosilicones, would exhibit interesting and useful surface behavior. The fundamental characteristics of fluorosilicones are summarized. Significant properties such as surface energy and glass transition temperature are reviewed and related to important applications like release behavior. A particularly interesting subset of these fluorocarbon/silicone hybrids is the perfluoroether-modified silicones. Useful new fluorosilicone materials for release and other applications are a consequence of having both side-chains and backbone that are flexible, low-glass-transition entities. © 2010 American Chemical Society.

Owen M.J.,Michigan Molecular Institute
Silicon | Year: 2015

The author, to his surprise, encountered glassblowing demonstrations on two recent cruises, one in the Caribbean and one on a Danube/Rhine river journey. © 2015 Springer Science+Business Media Dordrecht

Michigan Molecular Institute | Date: 2010-04-08

The present invention relates to surface modification of reverse osmosis membranes to introduce antifouling properties without compromising the separation properties of the original membranes. This approach utilizes: providing a coated membrane surface having enhanced hydrophilic characteristics that prevents the biofoulants from settling; have a surface that consists of hydrophilic brushes that unsettle any biofoulants that get through; and having antimicrobial ions present in the membrane coatings and able to remove or minimize any remaining biofoulants without leaching into the permeate. These coatings are made using dendritic polymers such as hyperbranched polymers or dendrimers.

The present invention provides a composition comprising an antimicrobial bilayer coating on a substrate which coating comprises: The bilayers, where an anionic outermost layer is present, is preferred. These coating compositions, applied to a substrate, are then crosslinked and finally treated with aqueous hypochlorite when NX is NCl. The substrate that is coated can be sterilized prior to applying the coating composition, but it is not required to do so. These coatings are useful for military and hospital equipment and environments, especially against spores.

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