Dispersion of reduced graphene oxide within thermoplastic starch/poly(lactic acid) blends investigated by small-angle X-ray scattering

Willian H Ferreira; Karim Dahmouche; Cristina T Andrade

doi:10.1016/j.carbpol.2018.12.055

Dispersion of reduced graphene oxide within thermoplastic starch/poly(lactic acid) blends investigated by small-angle X-ray scattering

Carbohydr Polym. 2019 Mar 15:208:124-132. doi: 10.1016/j.carbpol.2018.12.055. Epub 2018 Dec 18.

Authors

Willian H Ferreira¹, Karim Dahmouche², Cristina T Andrade³

Affiliations

¹ Instituto de Macromoléculas Professora Eloisa Mano, Universidade Federal do Rio de Janeiro, Centro de Tecnologia, Bloco J, Avenida Horácio Macedo 2030, 21941-598 Rio de Janeiro, RJ, Brazil.
² Campus de Duque de Caxias, Universidade Federal do Rio de Janeiro, Rodovia Washington Luiz, km 104, 25265-970, Duque de Caxias, RJ, Brazil.
³ Instituto de Macromoléculas Professora Eloisa Mano, Universidade Federal do Rio de Janeiro, Centro de Tecnologia, Bloco J, Avenida Horácio Macedo 2030, 21941-598 Rio de Janeiro, RJ, Brazil. Electronic address: ctandrade@ima.ufrj.br.

PMID: 30658782
DOI: 10.1016/j.carbpol.2018.12.055

Abstract

Reduced graphene oxide (rGO) was incorporated into plasticized cornstarch (TPS), poly(lactic acid) (PLA) and their blends. Small-angle X-ray scattering (SAXS) was used to investigate rGO dispersion within the materials. For the TPS/PLA blend at 70:30 composition, the incorporation of rGO led to a larger fraction of small-sized rGO sheets, which at 5.0 mass% content developed stable fractal structures and domains of correlated sheets. The formation of fractal structures resulted in substantial enhancements in macroscopic properties. For these hybrids, the electrical conductivity, melt viscosity, storage moduli and biodegradation rates presented enhancements in relation to the neat blend. For the TPS/PLA blend at 30:70 composition, SAXS results indicated the formation of smaller fractions of well-dispersed rGO sheets and of segregated larger rGO sheets. With rGO at 5 mass% content, less expressive increases in electrical conductivity, melt viscosity, storage moduli and biodegradation rates were observed.

Keywords: Biodegradation; Capillary rheometry; Dynamic mechanical analysis; Electrical conductivity; Graphene; Graphene oxide (PubChem CID: 124202900); Poly(lactic acid) (not found); Reduced graphene oxide (not found); Small-angle X-ray scattering; Starch (PubChem CID: 24836924).