Natrosol hydroxyethylcellulose (HEC), a nonionic, water-soluble polymer, is a white, free-flowing granular powder. It is made by reacting ethylene oxide with alkali-cellulose under rigidly controlled conditions. Natrosol; Natrosol 150L; Natrosol 180HH; Natrosol 180L; Natrosol 240JR; Natrosol 250; Natrosol 250 HHR; Natrosol 250G; Natrosol 250H; Natrosol 250H4R