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Made available in DSpace on 2020-12-12T01:28:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2021-07-15T15:07:17Z : No. of bitstreams: 1 S1516-14392019000700288.pdf: 6189288 bytes, checksum: 8f1bd0db89250519a54ed5770dd711ad (MD5) This study evaluates the properties of chitosan (CS) membranes modified with different percentages (0.5%, 3%, and 5% w/w) of a graphene-based material. Graphene oxide (GO) and reduced graphene oxide (RGO) were obtained by the chemical exfoliation of graphite and thermal reduction. Then, they were characterized by electrical conductivity measurements, FESEM, XRD, AFM, and Raman spectroscopy. The composites’ morphology was evaluated by FESEM. The degree of swelling over a 48 h period and mass loss behavior in phosphate-buffered saline solution for up to 70 days were also studied. The hydrophilicity of the CS and CS/graphene nanocomposites was examined by water contact angle. The graphene materials showed small stacks (6–8 sheets) with low defect density and nanoscale thickness (1.3–5.9 nm). The dispersion of the graphene material in the CS matrix significantly decreased the degree of swelling (460%) but did not modify the hydrolytic degradation process and the hydrophilicity of membranes. Pontifícia Universidade Católica do Rio Grande do Sul – PUCRS Escola Politécnica, Av. Ipiranga, 6681 Pontifícia Universidade Católica do Rio Grande do Sul – PUCRS Escola de Ciências, Av. Ipiranga, 6681 Instituto do Petróleo e dos Recursos Naturais – IPR, Av. Ipiranga, 6681 Prédio 96J Universidade Federal do Rio Grande do Sul – UFRGS Instituto de Física, Av. Bento Gonçalves, 9500 Universidade Estadual Paulista UNESP Faculdade de Engenharia, Avenida Brasil, 56 Universidade Federal do Rio Grande do Sul – UFRGS Instituto de Química, Av. Bento Gonçalves, 9500 Universidade Estadual Paulista UNESP Faculdade de Engenharia, Avenida Brasil, 56