Utilize este identificador para referenciar este registo:
https://hdl.handle.net/10216/103460
Autor(es): | Leandro Figueiredo Pedro Bandeira Adélio Mendes Margarida M. S. M. Bastos Fernão D. Magalhães |
Título: | Use of fluoropolymer permanent release coatings for molded polyurethane foam production |
Data de publicação: | 2012 |
Resumo: | The problem of adhesion of polyurethane foams to fluoropolymer permanent release mold coatings was studied. Two coatings, based on polytetrafluoroethylene (PTFE) and perfluoroalkoxy polymer (PFA) aqueous dispersions, respectively, were applied on aluminum plates, and the foam release performance evaluated. The PTFE coating displayed gradual loss of antiadhesion properties with consecutive exposure to the reactive mixture, which was associated with isocyanate surface penetration. Penetrant mass uptake experiments, performed on free films, indicated that PTFE retains about 10 times more isocyanate than PFA, probably because of its porous surface morphology. A synergistic effect was found by applying a very small quantity of a waterborne release agent on the PTFE coating, before every foam molding cycle. The release agent formed a protective barrier that minimized contact of the coating with the reactive mixture, allowing for stable and robust foam release performance. The problem of polyurea build-up, associated with the use of aqueous release agents, was not observed because of the small amounts of compound used. |
Assunto: | Engenharia dos materiais Materials engineering |
Áreas do conhecimento: | Ciências da engenharia e tecnologias::Engenharia dos materiais Engineering and technology::Materials engineering |
URI: | https://hdl.handle.net/10216/103460 |
Informação Relacionada: | info:eu-repo/grantAgreement/FCT - Fundação para a Ciência e a Tecnologia/Programa de Financiamento Plurianual de Unidades de I&D/FCOMP-01-0124-FEDER-022677/PROJECTO ESTRATÉGICO - UI 511 - 2011-2012/PEst-C/EQB/UI0511/2011 |
Tipo de Documento: | Artigo em Revista Científica Internacional |
Condições de Acesso: | restrictedAccess |
Aparece nas coleções: | FEUP - Artigo em Revista Científica Internacional |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
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68823.pdf Restricted Access | Artigo original publicado | 813.18 kB | Adobe PDF | Request a copy from the Author(s) |
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