Sodium Xylene Sulfonate is a surfactant often added to shampoos as a thickening agent; it is often found in personal care products, primarily in shampoos. It is has ability to serve as a claritant or wetting agent that helps a formula spread more easily and ensure efficient cleansing, according to Johnson & Johnson. Synonyms: Xylenesulfonic acids, sodium salts; SXS ; Sodium dimethylbenzenesulfonate. CAS No: 1300-72-7. Molecular Formula: C8H9Na S O3 Molar Mass: 208.21 g/mol.