title: Bacterial cellulose nanocrystals produced under different hydrolysis conditions: Properties and morphological features.
abstract: Bacterial cellulose (BC) is a polymer with interesting physical properties owing to the regular and uniform structure of its nanofibers, which are formed by amorphous (disordered) and crystalline (ordered) regions. Through hydrolysis with strong acids, it is possible to transform BC into a stable suspension of cellulose nanocrystals, adding new functionality to the material. The aim of this work was to evaluate the effects of inorganic acids on the production of BC nanocrystals (BCNCs). Acid hydrolysis was performed using different H2SO4concentrations and reaction times, and combined hydrolysis with H2SO4and HCl was also investigated. The obtained cellulose nanostructures were needle-like with lengths ranging between 622 and 1322nm, and diameters ranging between 33.7 and 44.3nm. The nanocrystals had a crystallinity index higher than native BC, and all BCNC suspensions exhibited zeta potential moduli greater than 30mV, indicating good colloidal stability. The mixture of acids resulted in improved thermal stability without decreased crystallinity.
authors.affiliation: Federal University of Ceará (UFC), Department of Chemical, Bloco 940, 60455-760 Fortaleza, Ceará, Brazil.
authors.forename: Niédja Fittipaldi
authors.initials: NF
authors.lastname: Vasconcelos
authors.affiliation: Federal University of Ceará (UFC), Department of Chemical, Bloco 940, 60455-760 Fortaleza, Ceará, Brazil.
authors.forename: Judith Pessoa Andrade
authors.initials: JP
authors.lastname: Feitosa
authors.affiliation: Centre of Biological Engineering - CEB, Institute for Biotechnology and Bioengineering (IBB), Department of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
authors.forename: Francisco Miguel Portela
authors.initials: FM
authors.lastname: da Gama
authors.affiliation: Embrapa Cotton - CNPA, Rua Oswaldo Cruz 1143, Centenário, 58428-095 Campina Grande, Paraíba, Brazil.
authors.forename: João Paulo Saraiva
authors.initials: JP
authors.lastname: Morais
authors.affiliation: Embrapa Tropical Agroindustry - CNPAT, Rua Dra Sara Mesquita 2270, Planalto do Pici, 60511-110 Fortaleza, Ceará, Brazil.
authors.forename: Fábia Karine
authors.initials: FK
authors.lastname: Andrade
authors.affiliation: Embrapa Tropical Agroindustry - CNPAT, Rua Dra Sara Mesquita 2270, Planalto do Pici, 60511-110 Fortaleza, Ceará, Brazil.
authors.forename: Men de Sá Moreira
authors.initials: MS
authors.lastname: de Souza Filho
authors.affiliation: Embrapa Tropical Agroindustry - CNPAT, Rua Dra Sara Mesquita 2270, Planalto do Pici, 60511-110 Fortaleza, Ceará, Brazil. Electronic address: morsyleide.rosa@embrapa.br.
authors.forename: Morsyleide de Freitas
authors.initials: MF
authors.lastname: Rosa
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D041821:Gluconacetobacter / Q000737:chemistry*; D006868:Hydrolysis; D053758:Nanoparticles; D013535:Suspensions
chemical_list: D013535:Suspensions; D002482:Cellulose
keywords: Bacterial cellulose; Cellulose nanocrystals; Hydrochloric acid; Hydrolysis; Sulfuric acid