Bacterial cellulose membrane with functional properties

Author(s)

Andreia Sofia de Sousa Monteiro

• Document type: Doctoral Thesis
• Press: Araraquara. 2019-12-19.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Química. Araraquara
• Defense date: 2019-12-04
• Advisor: Sidney José Lima Ribeiro

Abstract

This work reports the development of economic and environmentally friendly Bacterial Cellulose Membrane (BCM) with functional properties. The spherical mesoporous silica nanoparticles with average particle size around 51 ± 4 nm, obtained by sol-gel method and spherical silica nanoparticles with heterogeneous particles size distribution (20-40 nm) obtained through agro-industrial waste were prepared and functionalized by in situ and post-grafting methodology, respectively, with alkoxysilanes with easy-cleaning properties and natural dye obtained through natural extracts, namely curcuma. Anatase TiO2@SiO2 spherical nanocomposites prepared by the sol-gel method, have also been developed. Subsequently, these functional nanomaterials and the organosilanes 1,4 – bis(triethoxysilyl)benzene (BTEB), Bis(triethoxysilylpropyl)disulfide (BTPD) and 1,2-Bis(triethoxysilyl)ethane (BTSE), were successfully incorporated into BCM, by in situ and post-grafting methodologies. In the BCM functionalized with BTEB, BTPD and BTSE, spherical silica nanoparticles with porous structure and heterogeneous particle size, were formed on the cellulose fibers. The surface repellency of the functionalized BCM with silica nanoparticles containing easy-cleaning properties was remarkably enhanced. This BCM displaying phobicity to water, toluene, cyclohexane and artificial sweat. Specifically, the BCM functionalized by in situ and post-grafting with SiO2@F13TES, displayed a surface almost superhydrophobic (> 150°). Methyl violet 2B dye decomposition measurements showed that the BCMW-SiO2@TiO2 (BCM functionalized in wet state) presented a good self-cleaning performance showing fast Methyl violet 2B dye decomposition in 30 minutes. BCM with yellow-orange coloration from curcuma with good resistance to washing and high chemical stability have been developed. This versatile biomaterial emerge as a promising substrate with high added value being able possibly allow their application in several areas. (AU)

• FAPESP's process: 15/12908-2 - Development of colored silica nanoparticles of natural base, and its application in textile substrates
• Grantee: Andreia Sofia de Sousa Monteiro
• Support Opportunities: Scholarships in Brazil - Doctorate