| Autor: |
Ibarra D; Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain., Martín-Sampedro R; Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain., Wicklein B; Materials Science Institute of Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain., Borrero-López AM; Pro2TecS-Chemical Process and Product Technology Research Centre, Departamento de Ingeniería Química, ETSI, Campus de 'El Carmen', Universidad de Huelva, 21071 Huelva, Spain., Valencia C; Pro2TecS-Chemical Process and Product Technology Research Centre, Departamento de Ingeniería Química, ETSI, Campus de 'El Carmen', Universidad de Huelva, 21071 Huelva, Spain., Valdehíta A; Environment and Agronomy Department (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain., Navas JM; Environment and Agronomy Department (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain., Eugenio ME; Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain. |
| Abstrakt: |
In order to identify new sustainable sources for producing cellulose nanofibers (CNFs), fast-growing poplar ( Populus alba L.) wood was evaluated herein. For that purpose, bleached poplar kraft pulp was produced and submitted to TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) mediated oxidation (TEMPO-ox) chemical pretreatment followed by microfluidization. The resulting CNFs were thoroughly characterized, including a rheological study at different pH values. Poplar CNFs showed properties comparable to eucalypt CNFs (reference material for CNFs production), showing high carboxylate content (1048 ± 128 µmol g -1 ), fibrillation yield (87.3% ± 8.1%), optical transmittance (83% at 700 nm) and thermal stability (up to more than 200 °C). Regarding the rheological study, whereas pH from 4 to 10 did not produce significant changes in rheological behavior, a reduction of pH down to 1 led to an order-of-magnitude increase on the viscoelastic functions. Therefore, poplar CNF shows potential in the pH-sensitive hydrogels application field. Finally, the possible ecotoxicity of poplar CNF was assessed. The decrease in cell viability was very low so that only concentrations causing a 10% cytotoxicity could be calculated for the assay detecting alterations in cell metabolism (10 µg mL -1 ) and plasma membrane integrity (60 µg mL -1 ). |
