1
|
Ibarra D, Martín-Sampedro R, Wicklein B, Borrero-López AM, Valencia C, Valdehíta A, Navas JM, Eugenio ME. Populus alba L., an Autochthonous Species of Spain: A Source for Cellulose Nanofibers by Chemical Pretreatment. Polymers (Basel) 2021; 14:polym14010068. [PMID: 35012091 PMCID: PMC8747510 DOI: 10.3390/polym14010068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/19/2021] [Accepted: 12/22/2021] [Indexed: 12/31/2022] Open
Abstract
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).
Collapse
Affiliation(s)
- David Ibarra
- Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (D.I.); (R.M.-S.)
| | - Raquel Martín-Sampedro
- Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (D.I.); (R.M.-S.)
| | - Bernd Wicklein
- Materials Science Institute of Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC), Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain;
| | - Antonio M. Borrero-López
- Pro2TecS—Chemical Process and Product Technology Research Centre, Departamento de Ingeniería Química, ETSI, Campus de “El Carmen”, Universidad de Huelva, 21071 Huelva, Spain; (A.M.B.-L.); (C.V.)
| | - Concepción Valencia
- Pro2TecS—Chemical Process and Product Technology Research Centre, Departamento de Ingeniería Química, ETSI, Campus de “El Carmen”, Universidad de Huelva, 21071 Huelva, Spain; (A.M.B.-L.); (C.V.)
| | - Ana Valdehíta
- Environment and Agronomy Department (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (A.V.); (J.M.N.)
| | - José M. Navas
- Environment and Agronomy Department (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (A.V.); (J.M.N.)
| | - María E. Eugenio
- Forest Research Center (INIA, CSIC), Ctra. de la Coruña Km 7.5, 28040 Madrid, Spain; (D.I.); (R.M.-S.)
- Correspondence: ; Tel.: +34-913473948
| |
Collapse
|