1,1-Diphenylethylene mediates the radical polymerization of methyl acrylate or styrene.

Mediation by 1,1-Diphenylethylene generates low molecular weight polymer by a termination reaction.

[3] Additionally, because 1,1-Diphenylethylene has a lower pKa than styrene, it is an effective mediator in the anionic living polymerization of styrene-block-methyl methacrylate copolymers.

Polystyrene homopolymers can be "capped" with 1,1-Diphenylethylene before adding methyl methacrylate, effectively adjusting the pKa of the active chain end so that 1,4-addition to methyl methacrylate is favored over 1,2-addition.

[5] 1,1-Diphenylethylene is technical prepared by alkylating benzene by styrene in presence of a zeolite beta and subsequent dehydrogenation.