Diethylene glycol di(p-toluenesulfonate) is primarily used as a reactive intermediate in the synthesis of various polymers and organic compounds. It serves as a key building block in the production of specialty chemicals, particularly in the development of polyesters and polyethers, where it acts as a cross-linking agent. This compound is also utilized in the preparation of sulfonate esters, which are valuable in organic synthesis for creating complex molecular structures. Additionally, it finds application in the pharmaceutical industry for the modification of drug molecules to enhance their solubility or stability. Its role in material science includes the fabrication of advanced materials with tailored properties, such as improved thermal or mechanical performance.