title: Correlated and cooperative motions in segmental relaxation: Influence of constitutive unit weight and intermolecular interactions.
abstract: This work clarifies the notion of correlated and cooperative motions appearing during the α-relaxation process through the role of the molecular weight of the constitutive units and of the interchain dipolar interactions. By studying amorphous copolymers of poly(ethylene-co-vinyl acetate) with different vinyl acetate contents, we show that the correlated motions are not sensitive to the interchain dipolar interactions, in contrast to the cooperative motions, which increase with a strengthening of the intermolecular interactions for this sample family. Concerning the influence of the molecular weight m_{0}, the notion of "correlated motions" seems to be equivalent to the notion of "cooperative motions" only for low m_{0} systems.
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.
authors.forename: Bidur
authors.initials: B
authors.lastname: Rijal
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.|Normandie Université, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France.
authors.forename: Jorge Arturo
authors.initials: JA
authors.lastname: Soto Puente
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.
authors.forename: Bienvenu
authors.initials: B
authors.lastname: Atawa
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Delbreilh
authors.affiliation: Normandie Université, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France.
authors.forename: Kateryna
authors.initials: K
authors.lastname: Fatyeyeva
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.
authors.forename: Allisson
authors.initials: A
authors.lastname: Saiter
authors.affiliation: Normandie Université, UNIROUEN, LECAP, 76000 Rouen, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Dargent