Abstract
Compatibility between polymers with different glass transition temperatures controls the thermomechanical properties of blends. This work explores the segmental dynamics of poly(methyl acrylate) (PMA) chains when they are blended with polymers of different rigidities and miscibility. Inspired by the intriguing dynamic asymmetry of chains within the interfacial layer of nanoparticles, this study aims to understand dynamic heterogeneity in dynamically asymmetric blends of PMA/poly(methyl methacrylate) (PMMA), PMA/polystyrene (PS), and PMA/poly(ethylene oxide) (PEO) using the differential scanning calorimetry (DSC) and quasi-elastic neutron scattering (QENS) measurements below and above the glass transition temperature of PMMA or PS. Results revealed that the segmental jump distance of PMA increased on blending due to volume enhancement. The reduced effective diffusivity of PMA in PMMA is attributed to PMMA's enhanced flexibility (lower characteristic ratio, (Formula presented.)) and superior interaction (lower (Formula presented.)) when compared with the PS environment. The results demonstrate that the chain rigidity and miscibility affect the free volume, interchain cooperativity, and segmental dynamics in dynamically asymmetric blends.
| Original language | English |
|---|---|
| Pages (from-to) | 4177-4185 |
| Number of pages | 9 |
| Journal | Journal of Polymer Science |
| Volume | 62 |
| Issue number | 18 |
| DOIs | |
| State | Published - Sep 15 2024 |
Funding
Work at Oak Ridge National Laboratory's Spallation Neutron Source was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. ORNL is managed by UT\u2010Battelle, LLC, for U.S. DOE under Contract No. DEAC05\u201000OR22725. C. M. is funded by the Stevens Provost Fellowship program.
Keywords
- asymmetric blends
- jump diffusion
- poly(methyl acrylate) dynamics
- polymer blends
- quasi-elastic neutron scattering