Antioxidant TMQ (abbreviation TMQ, chemical name Polymerized 2,2,4-trimethyl-1,2-dihydroquinoline, also known as RD) is a commonly used rubber antioxidant belonging to the amine class. It appears as reddish-brown to amber flakes or granules, with low volatility and good solubility. TMQ is widely applied in tires, hoses, cables, and other rubber products. It provides excellent protection against thermal-oxidative aging and also offers some resistance to ozone degradation, though it does not provide protection against copper damage.