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Chemical modification in surface of cellulose nanofibrils CNFs (20 nm) from an endemic and non-significant value-added, Argentine bamboo, was developed. The modification in the CNFs was carried out with three simple routes using a low molecular weight polylactic acid synthesized in our laboratory (PLA1). The first step comprises of protection of the hydroxyl groups of PLA1 through a benzoylation (PLA1Bz). The next step consisted of the activation of carboxyl groups using thionyl chloride and the last reaction was the grafting of the modified PLA onto the CNFs (PLA1Bz-g-CNF). The covalently functionalization is confirmed by spectroscopically techniques as well as PLA1Bz-g-CNFs were characterized by thermal analyses. The PLA1Bz-g-CNFs were taken up such as nanocharges to improve properties of compatibilization and changing surface properties in films based on PLA. The comparison between the films with PLA1Bz-g-CNFs with respect to the physic mixture of the components (PLA1Bz/CNF), shows an improvement in the thermal, mechanical, and surface properties of the material, particularly when 5% of PLA1Bz-g-CNFs was added. The dispersive (γS D) component of film is increased in 36.1 mN/m respect to 29.3 mN/m from the films obtained with the physic mixture nanofibrils without modification and a plasticizing effect was noticed in the final material. • Chemical grafting with short PLA on CNF was used to obtain better compatibility between the hydrophobic PLA matrix and CNFs. • Nanofibrils modified showed an improved thermal stability than unmodified nanofibrils. • Modified CNFs added into the PLA matrix films, reduced the polar contributions of the nanofibrils in the films. • Low molecular weight PLA chains grafted onto the nanofiber surface inhibit the nucleating effect, thus crystallinity in films. • Plasticizing effect in PLA films with the addition of modified nanofibers was noticed in the mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract: A water-soluble neutral polysaccharide (GLP-F1-1) was isolated from the fruiting bodies of Ganoderma lucidum by DEAE Sepharose Fast Flow and Sephacryl S-500 High Resolution Chromatography. The neutral polysaccharide had an average molecular weight (M w) of approximately 2.5×106 kDa. GC analysis showed that this polysaccharide was mainly composed of glucose and galactose in the molar ratio of 34:1. 1H and 13C NMR spectroscopy in combination with GC–MS technique indicated that the new polysaccharide had a backbone chain of 1,4-disubstituted-β-glucoseopyranose and 1,4,6-trisubstituted-β-glucoseopyranosyl, while the branched chains were mainly composed of 1,6-disubstituted-β-glucopyranosyl and 1,4-disubstituted-β-galactoseopyranosyl residues. [Copyright &y& Elsevier]