1. Determination of reagents for organic compounds with conjugated double bonds. It is also used in synthetic resins, coatings, pesticides, medicine, food, and lubricant additives. 2. Used in organic synthesis, synthetic fiber intermediate. Used as an analytical reagent, such as a reagent for the determination of organic compounds with conjugated double bonds. 3. Used as a curing agent for epoxy resins, and can also be used for grafting with EVA and PE blends to prepare new hot melt adhesive polymers to improve adhesion. It can also be used as a modified monomer for the production of acrylate emulsion and grafting with SBS. In the pesticide industry, it is used in the manufacture of malathion, maleic hydrazide, fungicides, and herbicides. It is used in the pharmaceutical industry to manufacture long-acting sulfa, aminophylline and other drugs. In the food industry, it is used in the manufacture of sour agents such as malic acid and tartaric acid. It is also used as papermaking sizing agent, lubricating oil pour point depressant, water quality stabilizer, ink additive, fabric softening finishing agent and used in the manufacture of surfactants.