| Autor: |
Peponi L; Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC., Calle Juan de la Cierva 3, 28006 Madrid, Spain., Barrera-Rivera KA; Departamento de Química, Universidad de Guanajuato, Noria Alta s/n, Guanajuato 36050, Guanajuato, Mexico., Kenny JM; Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC., Calle Juan de la Cierva 3, 28006 Madrid, Spain., Marcos-Fernandez Á; Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC., Calle Juan de la Cierva 3, 28006 Madrid, Spain., Martinez-Richa A; Departamento de Química, Universidad de Guanajuato, Noria Alta s/n, Guanajuato 36050, Guanajuato, Mexico., López D; Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC., Calle Juan de la Cierva 3, 28006 Madrid, Spain. |
| Abstrakt: |
In this work, the chemical modification of cellulose nanocrystals (NCs) using an enzyme as a catalyst has been performed by a “grafting from” reaction, in order to covalently functionalize the external surface of NCs with both poly(L-lactic acid) (PLLA) and poly(ε-caprolactone) (PCL) by ring-opening polymerization. Firstly, cellulose nanocrystals were prepared from commercial cellulose microcrystals by acid hydrolysis and then functionalized by using Yarrowia lipolytica lipase immobilized on Lewatit resin as a catalyst. To confirm the success of the grafting reactions, 1H-NMR has been performed as well as FT-IR and Raman spectroscopy. Moreover, thermogravimetric analysis has been used to determine the amount of polymeric chains grafted onto the surface of cellulose nanocrystals. Furthermore, the crystalline nature of the polymeric chains grafted onto the cellulose surface has been studied by DSC, X-ray scattering, as well as SAXS analysis. To our knowledge, it is the first time that a biocatalyst approach has been used to obtain biopolymeric functionalized cellulose nanocrystals. |
