Impact of Degree of Ethoxylation on Sodium Lauryl Ether Sulfate Surfactant Adsorption onto Silicone-in-Water Emulsion Droplets.

Silicone-in-water emulsions have found widespread use as lubricants, water repellants, softeners, binders, antiblocking agents, antislip agents, and defoamers across a diverse range of markets including textiles, coatings, pharmaceuticals, and home and personal care. Stable incorporation of silicone emulsions into formulated products for these applications can be a challenge. This study seeks to enable formulation by investigating the impact of the degree of ethoxylation of sodium lauryl ether sulfate (SLES) surfactants on their ability to displace surfactant stabilizer at the silicone-water interfaces of polydimethylsiloxane (PDMS)-in-water emulsion droplets.

Removing acoustic ringing baseline curvature in C NMR spectra for quantitative analyses.

C nuclear magnetic resonance (NMR) is traditionally considered an insensitive technique, requiring long acquisition times to measure dilute functionalities on large polymers. With the introduction of cryoprobes and better electronics, sensitivity has improved in a way that allows measurements to take less than 1/20th the time that they previously did. Unfortunately, a high Q-factor with cryoprobes creates baseline curvature related to acoustic ringing that affects quantitative NMR analyses.

Backbone-Degradable Vinyl Acetate Latex: Coatings for Single-Use Paper Products.

We report an approach to waterborne and degradable latex polymers. Emulsion polymerization of vinyl acetate (VA) with the cyclic ketene acetal 2-methylene-1,3-dioxepane (MDO) yields polymer particles and latex-based coatings that are hydrolytically degradable due to the presence of backbone ester groups. Polymerization under mildly basic conditions (pH 8) and at low temperature (40 °C) is critical: if the in-process pH is too acidic or the temperature too high, MDO is lost to hydrolysis, but when the media is too alkaline, VA monomer rapidly hydrolyzes.