Publication detail

Frontally polymerized foams: thermodynamic and kinetical aspects of front hindrance by particles

LEPCIO, P. DAGUERRE-BRADFORD, J. CRISTADORO, A. SCHUETTE, M. LESSER, A.

Original Title

Frontally polymerized foams: thermodynamic and kinetical aspects of front hindrance by particles

Type

journal article in Web of Science

Language

English

Original Abstract

Frontal polymerization (FP) is a solvent-free, energy-efficient process where a self-propagating polymerization reaction with a characteristic sharp temperature gradient at the front head propagates through the resin to provide the curing conditions. It relies on the enthalpic balance, which spreads the reaction to unreacted resin in the neighborhood. Therefore, the FP is sensitive to the presence of non-reactive volumes, such as boundaries, fillers, or other additives, that retain heat from the front but produce no enthalpy in return. On the other hand, the front's high temperature could be used to initiate other processes, such as foaming, incorporating them into a simple single-step fabrication procedure. This study used silica particles of two different sizes (14 nm and 200-300 nm) in an epoxy-based FP foam as a representative filler to probe the constraints imposed by non-reactive additives. The presence of particles visibly hindered the front propagation, increased the foam density and even corrupted the frontal regime in some cases. We show that preheating or chemical composition changes are viable approaches to address the fillers' adverse effects. Furthermore, we present evidence that the reduced reaction enthalpy caused by silica nanoparticles, was balanced by the lower heat capacity of our model system. At the same time, the front hindrance was attributed to changes in reaction kinetics and the heat distribution around the front. These results set up essential narratives for the design and practical applications of frontally polymerized foams with non-reactive fillers.

Keywords

composites

Authors

LEPCIO, P.; DAGUERRE-BRADFORD, J.; CRISTADORO, A.; SCHUETTE, M.; LESSER, A.

Released

31. 7. 2023

Publisher

ROYAL SOC CHEMISTRY

Location

CAMBRIDGE

ISBN

2051-6355

Periodical

Materials Horizons

Year of study

10

Number

8

State

United Kingdom of Great Britain and Northern Ireland

Pages from

2989

Pages to

2996

Pages count

8

URL

https://pubs.rsc.org/en/content/articlelanding/2023/MH/D2MH01553F

Full text in the Digital Library

http://hdl.handle.net/11012/245010

BibTex

@article{BUT183780,
  author="Petr {Lepcio} and John {Daguerre-Bradford} and Anna Maria {Cristadoro} and Markus {Schuette} and Alan J. {Lesser}",
  title="Frontally polymerized foams: thermodynamic and kinetical aspects of front hindrance by particles",
  journal="Materials Horizons",
  year="2023",
  volume="10",
  number="8",
  pages="2989--2996",
  doi="10.1039/d2mh01553f",
  issn="2051-6355",
  url="https://pubs.rsc.org/en/content/articlelanding/2023/MH/D2MH01553F"
}