resumo
Bacterial nanocellulose (BC)-based composites containing poly(2-hydroxyethyl methacrylate) (PHEMA), poly(methacroylcholine chloride) (PMACC) or poly(methacroylcholine hydroxide) (PMACH) were characterized by inelastic neutron scattering (INS) spectroscopy, combined with DFT (density functional theory) calculations of model systems. A reasonable match between calculated and experimental spectral lines and their intensities was used to support the vibrational assignment of the observed bands and to validate the possible structures. The differences between the spectra of the nanocomposites and the pure precursors indicate that interactions between the components are stronger for the ionic poly(methacrylate) derivatives than for the neutral counterpart. Displaced anions interact differently with cellulose chains, due to the different ability to compete with the O-H center dot center dot center dot O hydrogen bonds in cellulose. Hence, the INS is an adequate technique to delve deeper into the structure and dynamics of nanocellulose-based composites, confirming that they are true nanocomposite materials instead of simple mixtures of totally independent domains.
palavras-chave
BACTERIAL CELLULOSE NANOCOMPOSITES; DENSITY FUNCTIONALS; IN-SITU; SPECTROSCOPY; PERFORMANCE; MEMBRANES; CARBON; M06
categoria
Biochemistry & Molecular Biology; Chemistry
autores
Vilela, C; Freire, CSR; Araujo, C; Rudic, S; Silvestre, AJD; Vaz, PD; Ribeiro-Claro, PJA; Nolasco, MM
nossos autores
Armando Jorge Domingues Silvestre
Professor Catedrático
Carla Vilela
Investigador Principal
Carmen Sofia da Rocha Freire Barros
Investigador Principal
Catarina Araújo
Estudante de doutoramento
Mariela Martins Nolasco
Investigador Auxiliar
Paulo Ribeiro-Claro
Professor Associado com Agregação
Pedro Miguel Duarte Vaz
ColaboradorGrupos
4 - biorrefinarias, materiais de origem biológica e reciclagem
6 - simulação computacional e modelação multi-escala
agradecimentos
This work was developed within the scope of the projects CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. FCT-Fundacao para a Ciencia e a Tecnologia, is also acknowledged for the research contracts under FTC Investigator Program to M.M.N. (IF/01468/2015) and Scientific Employment Stimulus to C.V. (CEECIND/00263/2018). The STFC Rutherford Appleton Laboratory is acknowledged for access to neutron beam facilities.