title: Dramatic reduction of the effect of nanoconfinement on the glass transition of polymer films via addition of small-molecule diluent.
abstract: The effect of nanoconfinement on the glass transition temperature T(g) in thin polymer films is studied as a function of added small-molecule diluent or plasticizer. The decrease [increase] in T(g) found in nanoconfined, neat polystyrene [poly(2-vinyl pyridine)] is suppressed by added diluent, with 13-20 nm thick polystyrene films exhibiting bulk T(g) upon addition of 9 wt % pyrene or 4 wt % dioctylphthalate [corrected]. This is explained by a connection between the size scale of the cooperative dynamics associated with T(g), which decreases with added diluent, and the size scale of the nanoconfinement effect.
authors.affiliation: Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ellison
authors.forename: Robert L
authors.initials: RL
authors.lastname: Ruszkowski
authors.forename: Nathaniel J
authors.initials: NJ
authors.lastname: Fredin
authors.forename: John M
authors.initials: JM
authors.lastname: Torkelson