Polyethers are fundamental to the chemistry used to create the diverse portfolio of ingredients offered by Ashland. Polyethylene glycol (PEG) is a polyether homopolymer of ethylene oxide readily available in a range of molecular weights. PEG is a common raw material used in the development of a class of rheology modifiers known as nonionic synthetic associative thickeners (NSATs) which are extensively used in the formulation of waterborne coatings. hydrophobic modification of polyethers like PEG, often combined with an additional polymerization step to build molecular weight, is a critical feature of NSATs.
Hydrophobically modified polyacetal polyethers (HM-PAPEs) are a family of NSATs invented at Ashland which are especially effective additives for architectural latex paints. The hydrophobic portions of the HM-PAPE molecule associate with each other at the exclusion of water to form micelles. The micelles are absorbed onto the latex surface creating a transient three-dimensional network. By varying the molecular weight and hydrophobic composition of these polymers, the high and low shear rheology can be tuned for the desired application performance.
With regards to coatings application performance, polyether based NSATs provide better flow, leveling, and spatter resistance along with thicker film build and improved brush feel over many conventional thickeners.