BTMS-25 vs BTMS-50: How to Choose the Right Conditioning Emulsifier The growth of solid conditioner bars, silicone-free hair care and concentrated rinse-off products has brought renewed attention to one of the most versatile ingredients in modern hair-care formulation: Behentrimonium Methosulfate, commonly known as BTMS. Despite the word “sulfate” in its name, Behentrimonium Methosulfate is not a cleansing sulfate such as …