Imperial College London
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ProfessorJoaoCabral

Faculty of Engineering, Department of Chemical Engineering

Professor of Soft Matter
 
 
 
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Contact

 

+44 (0)20 7594 5571j.cabral Website

 
 
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Assistant

 

Mrs Sarah Payne +44 (0)20 7594 5567

 
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Location

 

517AACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{White:2020:10.1021/acs.macromol.0c00706,
author = {White, RP and Aoki, Y and Higgins, JS and Keddie, JL and Lipson, JEG and Cabral, JT},
doi = {10.1021/acs.macromol.0c00706},
journal = {Macromolecules},
pages = {7084--7095},
title = {Thermodynamics of model PαMSAN/dPMMA blend: a combined study by SANS, ellipsometry, and locally correlated lattice (LCL) theory},
url = {http://dx.doi.org/10.1021/acs.macromol.0c00706},
volume = {53},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We combine experiment and theory to elucidate how small, local, structural changes can impact miscibility in polymer blends. Small-angle neutron scattering (SANS) experiments yield both the phase boundaries and the temperature dependence of the second derivative of the free energy of mixing. We demonstrate here, for the first time, that a fundamental characterization of pure component properties can be achieved through ellipsometry measurements on films of pure polymers (thickness ∼200 nm) to provide key data on the volume (or thickness)–temperature relationships; this development is significant given the scarcity of precise pressure–volume–temperature (PVT) data on pure polymers and blends. The experimental measurements allow us to undertake a detailed thermodynamic analysis of mixing using the locally correlated lattice (LCL) theory, which has been shown to be effective in rationalizing blend miscibility in terms of the pure component properties. We focus here on polymer blends of poly(α-methyl styrene-co-acrylonitrile) (PαMSAN) with deuterated poly(methyl methacrylate) (dPMMA), which differ in the degree of tacticity in the dPMMA component (atactic or syndiotactic), leading to an increase in miscibility for the latter. By combining LCL analysis of pure and mixed systems, we are able to connect tacticity changes to shifts in local nonbonded interactions, in free volume, and in thermal expansion coefficients, which in turn impact the thermodynamic compatibility of the blend components.
AU  - White,RP
AU  - Aoki,Y
AU  - Higgins,JS
AU  - Keddie,JL
AU  - Lipson,JEG
AU  - Cabral,JT
DO  - 10.1021/acs.macromol.0c00706
EP  - 7095
PY  - 2020///
SN  - 0024-9297
SP  - 7084
TI  - Thermodynamics of model PαMSAN/dPMMA blend: a combined study by SANS, ellipsometry, and locally correlated lattice (LCL) theory
T2  - Macromolecules
UR  - http://dx.doi.org/10.1021/acs.macromol.0c00706
UR  - https://pubs.acs.org/doi/10.1021/acs.macromol.0c00706
UR  - http://hdl.handle.net/10044/1/82888
VL  - 53
ER  -
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