Ethylene oxide-propylene oxide block copolymer, MW 1900 Ethylene oxide/propylene oxide block copolymer, (min avg MW 1900) Peg/ppg block copolymer, MW 1900 Poloxamer-105 Polyoxyethylene-polyoxypropylene block copolymer, MW 1900 alpha-Hydro-omega-hydroxypoly(oxyethylene)/poly(oxypropylene)(minimum 15 moles)/poly(oxyethylene) block copolymer, min MW