Used as a monomer in the synthesis of high-performance polymers such as liquid crystalline polyesters and polyamides. The rigid biphenyl core contributes to thermal stability and mechanical strength, while the 2,2'-dimethyl substituents enhance hydrophobicity to reduce moisture absorption and improve processability in the resulting materials. Commonly applied in engineering plastics and advanced composite materials where resistance to heat and chemicals is required. Also utilized in specialty membranes and electronic materials due to its structural rigidity and ability to promote molecular alignment.