Sodium Trimetaphosphate (STMP) is a Sodium Phosphate salt (NaPO3)3, supplier and exporter. Sodium Trimetaphosphate, Anhydrous (STMP) Powder is a clean, white powder. Sodium Trimetaphosphate. Applications include food processing, starch modification, pharmaceuticals, and potable water treatment.Application: Sodium Trimetaphosphate (STMP) is a Sodium Phosphate salt (NaPO3)3, that when added to gypsum can help to optimize the setting time while enhancing the structural integrity of the wallboard. STMP is an important additive in the production of high throughput and high quality wallboard for use by businesses and individuals in the construction and home remodeling industry.Dose: Note: