Journal of Materials Science

, Volume 52, Issue 9, pp 5380–5389 | Cite as

Amino-silica microcapsules as effective curing agents for polyurethane foams

  • Mónica V. Loureiro
  • Maria José Lourenço
  • Aster De Schrijver
  • Luís F. Santos
  • João C. Bordado
  • Ana C. MarquesEmail author
Original Paper


The present paper regards the development of functional microcapsules (MCs), containing encapsulated glycerol, to act as sustainable solid curing agents for one-component polyurethane (PU) foams. They consist of silica-based MCs with an aminosilane surface treatment, obtained through sol–gel processing technique. These MCs are intended to burst and release their content only at the spraying process, in order to promote an accelerated curing of the PU foam. The superficial amino groups react with the isocyanate groups present in the PU pre-polymer, producing polyurea moieties on the MCs’ surface, which prevents the leaching of encapsulated glycerol inside the PU aerosol can. This enables the long shelf life of the product, required for commercial application. The amino-silica MCs exhibit a perfect spherical shape, without significant leaching, in opposition to silica-based MCs and led to a significant increase in the curing rate of the PU foam. The study involved various characterization techniques, such as scanning electron microscopy, Fourier transformed infrared spectroscopy, thermogravimetric analyses, leaching and curing speed evaluation.


Foam Polyurea Isocyanate Group Aminosilane Porous Microsphere 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



ACM acknowledges the financial support from Science and Technology Foundation (FCT) through Post-Doc fellowship (SFRH/BPD/96697/2013). We are grateful to Profs. Mario Pagliaro and Rosaria Cirimmina for purposeful cooperation and to Prof. Ricardo Simões for the development and supply of the nozzle.


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Centro de Química Estrutural, Faculdade de CiênciasUniversidade de LisboaLisbonPortugal
  2. 2.Greenseal Research Ltd, Parque Industrial de Vendas NovasVendas NovasPortugal
  3. 3.Centro de Química Estrutural, Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal
  4. 4.Centre for Natural Resources and the Environment (CERENA), Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal
  5. 5.Departamento de EngenhariaUniversidade Atlântica, Fábrica da Pólvora de BarcarenaBarcarena, OeirasPortugal

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