Effect of Thickness on the Thermo-Mechanical Response of Free-Standing Thermoset Nanofilms from Molecular Dynamics
Abstract
We characterize how film thickness affects the thermomechanical response of free-standing nanofilms composed of a thermoset polymer, diglycidyl ether of Bisphenol A (DGEBA) with 3,3'-diaminodiphenyl sulfone (33DDS), via molecular dynamics. We find that the glass transition temperature, Young's modulus, and yield stress of the films decrease with decreasing thickness with the later two properties deviating from their bulk values at slightly larger thicknesses. The relative role of (i) intrinsic size effects, (ii) changes in quench depth (T - T(g)), and (iii) variability in curing degree, on the depression of mechanical response of ultrathin films, are quantified. We find that intrinsic size effects contribute over 60% of the total change in mechanical response for the entire range of thicknesses studied.
Keywords
GLASS-TRANSITION TEMPERATURE; THIN POLYSTYRENE FILMS; POLYMER-FILMS; SIMULATIONS; SURFACE; MEMBRANES; BEHAVIOR; ROBUST; BULK
DOI
10.1021/ma201927n
Citation
Macromolecules, 2011, 44 (23), pp 9448–9454
Date of this Version
12-13-2011
Recommended Citation
Li, Chunyu and Strachan, Alejandro, "Effect of Thickness on the Thermo-Mechanical Response of Free-Standing Thermoset Nanofilms from Molecular Dynamics" (2011). Birck and NCN Publications. Paper 924.
http://dx.doi.org/10.1021/ma201927n