Terephthaloyl chloride
（重定向自Terephthaloyl dichloride）
![Ball-and-stick model of the terephthaloyl chloride molecule](/Images/godic/202502/15/Terephthaloyl_chloride_3D_ball0739.png")
![](/Images/godic/202502/15/Kevlar_chemical_synthesis0739.png")
Terephthaloyl chloride (TCL, 1,4-benzenedicarbonyl chloride) is the acid chloride of terephthalic acid and is one of two monomers used to make Kevlar(R), the other being p-phenylenediamine. Its CAS reference number is 100-20-9 and its chemical formula is C8H4Cl2O2.