Polymeric membranes with antioxidant activity based on cellulose esters and poly(vinylidene fluoride)/cellulose ester blends

Abstract

A series of novel cellulose membranes with antioxidant activity was prepared and characterized. Microcrystalline cellulose was functionalized with lipoic acid, ferulic acid and alpha-tocopherol moieties. These materials were characterized by FT-IR and NMR spectroscopy and their degree of substitution (DS) was determined by volumetric analysis. The manuscript discusses the antioxidant activity of cellulose derivatives in inhibiting lipid peroxidation in ratliver microsomal membranes, induced in vitro by two different sources of free radicals: 2,2 0 -azobis-(2-amidinopropane) (AAPH), which exogenously produces peroxyl radicals by thermal decomposition, and tertbutyl hydroperoxide (tert-BOOH), which endogenously produces alkoxyl radicals by Fenton reactions. Membranes were prepared by the nonsolvent-induced phase inversion technique. Membranes of the pure cellulose derivatives were thin, mechanically weak and generally unsuitable for practical application. As an alternative, mechanically resistant poly(vinylidene fluoride)/cellulose ester blend membranes were obtained by direct phase inversion of the polymer/ polymer/solvent mixture. These membranes were characterized by means of water permeability measurements, optical and scanning electron microscopy, determination of the antioxidant activity in comparison with starting materials. The membranes exhibited a good preservation of peroxidation inhibition and the performance of this kind of cellulose membrane as a scavenger of Reactive Oxygen Species (ROS) offers interesting perspectives for an effective control of intradialytic oxidative stress.

Surface modification of cellulose nanocrystals with different acid anhydrides for improved dispersion in poly(butylene succinate)

“…Methods for CNC modication, such as esterication, gra copolymers, acetylation, and silylation, have been developed with the aim of overcoming this problem. [13][14][15][16] The dispersion of CNC may be improved, for example, by reducing the number of hydroxyl groups via esterication.…”

Fabrication of highly ordered porous membranes of cellulose triacetate on ice substrates using breath figure method

“…In this article, we obtained a highly ordered porous membrane of cellulose triacetate (CTA) using an ice substrate by the breath figure method. Due to its good mechanical properties, CTA is an appropriate cellulose‐based material to prepare porous membranes . The effects of polymer concentration and substrate material on the formed porous structures were investigated.…”

Conferring antioxidant capacity to cellulose based materials by using enzymatically-modified products

“…In this context, López-de-Dicastillo et al (López de Dicastillo et al 2012), studied antioxidant packaging films consisting of ethylene vinyl alcohol (EVOH) copolymers, Barbosa-Pereira et al (Barbosa-Pereira et al 2013), assessed tocopherolcontaining active packaging films made of low density polyethylene (LDPE) and Kanatt et al (Kanatt et al 2012), investigated active chitosan-polyvinyl alcohol films with natural mint and pomegranate peel extracts. Cellulose derivatives such as microcrystalline, carboxymethyl and ethyl cellulose have previously been used as carrier materials to prepare advanced materials with antioxidant properties (Jansen et al 2011;Hsu and Kilmartin 2012;Serrano Cruz et al 2013); by contrast, paper has seemingly never to date been used as carrier material for this purpose.…”