Scaling Behavior of Polymer Films in Nonequilibrium
ABSTRACT :
Rapid industrial processing conditions often freeze polymers in nonequilibrium conformations, which, in turn, manifest into material properties that differ, and often improve significantly from their equilibrium counterparts. This suggests that controlling processing pathways may provide a lever to control the properties of polymers. However, our understanding of the correlations between processing pathways and emerging macroscopic properties and microscopic reasons underlying the observed deviations in properties are still elusive. Thus, we often rely on empirical relations, imposing a trial-and-error approach to achieve desired material properties. Considering these aspects, I will discuss our recent efforts, based on spin-coated polymer films, revealing the existence of scaling relations between chain conformations inherited during preparation and their macroscopic mechanical properties like residual stresses, their relaxation times, and the probability of film rupture. Such quantitative correlations allowed us to propose that the rapid processing stages induce long-living molecular correlations, which might be the microscopic origin underlying various nonequilibrium phenomena observed in polymer films.