Glass-Transition Dynamics of Mixtures of Linear Poly(Vinyl Methyl Ether) with Single-Chain Polymer Nanoparticles: Evidence of a New Type of Nanocomposite Materials

Single-chain polymer nanoparticles (SCNPs) obtained through chain collapse by intramolecular cross-linking are attracting increasing interest as components of all-polymer nanocomposites, among other applications. We present a dielectric relaxation study on the dynamics of mixtures of poly(vinyl meth...

Full description

Bibliographic Details
Authors: Robles Hernández, Beatriz, González Burgos, Marina, Pomposo Alonso, José Adolfo, Colmenero de León, Juan, Alegría Loinaz, Iñaki
Format: article
Publication Date:2019
Country:España
Institution:Universidad del País Vasco
Repository:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/32744
Online Access:http://hdl.handle.net/10810/32744
Access Level:Open access
Keyword:nanocomposites
single-chain polymer nanoparticles
polymer blends
dielectric relaxation
glass transition
poly(ethylene oxide)
segmental dynamics
relaxation
noncovalent
covalent
delivery
design
blends
NMR
Description
Summary:Single-chain polymer nanoparticles (SCNPs) obtained through chain collapse by intramolecular cross-linking are attracting increasing interest as components of all-polymer nanocomposites, among other applications. We present a dielectric relaxation study on the dynamics of mixtures of poly(vinyl methyl ether) (PVME) and polystyrene (PS)-based SCNPs with various compositions. Analogous dielectric measurements on a miscible blend of PVME with the linear precursor chains of the SCNPs are taken as reference for this study. Both systems present completely different behaviors: While the blend with the linear precursor presents dynamics very similar to that reported for PVME/PS miscible blends, in the PVME/SCNP mixtures there are an appreciable amount of PVME segments that are barely affected by the presence of SCNPs, which nearly vanishes only for mixtures with high SCNP content. Interestingly, in the frame of a simple two-phase system, our findings point towards the existence of a SCNP-rich phase with a constant PVME fraction, regardless of the overall concentration of the mixture. Moreover, the dynamics of the PVME segments in this SCNP-rich phase display an extreme dynamic heterogeneity, a signature of constraint effects.

Similar Items