DPNB - Dipropylene Glycol Monobutyl Ether

About This Product

Dipropylene glycol n-butyl ether, DPnB, has CAS number 29911-28-2 and combines a two-unit propylene glycol backbone with a four-carbon butyl ether cap. It is a clear colourless liquid with limited water miscibility and a high boiling point, supplied as an isomer mixture. It is the strongest coalescent of the dipropylene series, and both halves of the molecule contribute. The butyl group gives high affinity for acrylic and vinyl-acrylic polymers, so the solvent partitions readily into the latex particle and softens it efficiently, which means less is needed to bring the minimum film-forming temperature down to a workable level. The two-unit backbone gives a boiling point high enough that the solvent survives well past the point at which the water has gone, keeping the particles soft through the whole fusion stage. Its limited water miscibility is part of the design rather than a defect: a coalescent that stayed dissolved in the water phase would leave with it instead of entering the polymer. Low addition levels also help formulators meet VOC limits. It is used as a coalescent in architectural and industrial latex paints, in cleaners, printing inks and coil coatings. Bio Green Chem supplies DPnB to specification on assay, water, acidity, colour, residue and isomer distribution.