Polyurethane films formation from microcrystalline cellulose as a polyol and cellulose nanocrystals as additive: Reactions favored by the low viscosity of the source of isocyanate groups used

Autor(es)

Porto, Deyvid S. ; de Faria, Clara Maria Gonsalves ; Inada, Natalia M. ; Frollini, Elisabete

• Tipo de documento: Artigo Científico
• Fonte: International Journal of Biological Macromolecules; v. 236, p. 14-pg., 2023-03-17.

Resumo

To simultaneously form films while synthesizing solvent-free and catalyst-free bio-based polyurethanes, hex-amethylene diisocyanate trimer was selected as an isocyanate group source to produce a low-viscosity reaction medium for dispersing high contents of microcrystalline cellulose (MCC, polyol) and cellulose nanocrystals (CNC). Castor oil was used as an additional polyol source. Up to 80 % of the MCC was dispersed, producing a film exhibiting the highest Tg (72 degrees C), tensile strength (18 MPa), and Young's modulus (522.4 MPa). 12.5 % (30 % MCC) and 7.5 % (50 % MCC) of CNC dispersed in the reaction medium formed films stiffer than their coun-terparts. All the films exhibited transparency and high crystallinity. The contact angle/zeta potential (zeta) indi-cated hydrophobic film surfaces. At pH 7.4, zeta suggested that the films interacted with physiological fluids favorably. The films were non-cytotoxic, and the composites exhibited cell growth compared with the control. The reported results, as far as it is known, are unprecedented. (AU)

• Processo FAPESP: 13/07276-1 - CEPOF - Centro de Pesquisa em Óptica e Fotônica
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs