Artículos de revistas
Partially fluorinated polymer networks: Surface and tribological properties
Fecha
2010-10-28Registro en:
Miccio, Luis Alejandro; Liaño, R.; Schreiner, Wido H.; Montemartini, Pablo Ezequiel; Oyanguren, Patricia Angelica; Partially fluorinated polymer networks: Surface and tribological properties; Elsevier; Polymer; 51; 26; 28-10-2010; 6219-6226
0032-3861
CONICET Digital
CONICET
Autor
Miccio, Luis Alejandro
Liaño, R.
Schreiner, Wido H.
Montemartini, Pablo Ezequiel
Oyanguren, Patricia Angelica
Resumen
Functionalization of epoxy-based networks by the preferential surface enrichment of perfluorinated tails to achieve hydrophobic surface is described. Two series of crosslinked fluorinated epoxy-based materials containing variable fluorine contents (from 0 to 5 wt % F) were prepared using formulations based on partially fluorinated diamine, epoxy monomer and a curing agent. The epoxy monomer was based on diglycidyl ether of bisphenol A (DGEBA) while the curing agents were either propyleneoxide diamine (JEFFAMINE) or 4,4′-methylenebis(3-chloro 2,6-diethylaniline) (MCDEA). The selected fluorinated epoxies (FE) were: 2,2,3,3,4,4,5,5,6,6,7,7,8,9,9,9-hexadecafluoro-8-trifluoromethyl nonyloxirane (FED3) and 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluoro nonyloxirane (FES3). The influence on surface properties of the architecture of FE, and the molecular structure of the unit building blocks was analyzed and discussed. It was found that both series showed high hydrophobicity and oleophobicity, independently of the crosslink density, bulk composition, and curing conditions. XPS measurements showed a surface composition much richer in fluorinated segments than expected from bulk composition. Fluorine enrichment was also manifested at the polymer/aluminium interface for JEFFAMINE-based networks. This observation is discussed in terms of the molecular weight dependence of surface tension and configurational entropy of the thermosetting matrix. At least for the range of this study, while increasing the amount of fluorine incorporated in both network series, dynamic friction is reduced due to surface migration of fluorine species during polymerization.