Cellulose/TiO2 Hybrid Spherical Microbeads Prepared by a Viscose Phase Separation Method: Control of the Distribution of TiO2 Particles in a Sphering System

Abstract

ABSTRACT:Cellulose/TiO 2 hybrid spherical microbeads were prepared by a one-step phase separation method using a cellulose xanthate aqueous solution and a sodium polyacrylate aqueous solution. Various types of cellulose/ TiO 2 hybrid spherical microbeads were obtained by using the several kinds of TiO 2 particles. The resulting hybrid spherical microbeads showed respective differences in the distribution of TiO 2 particles. EPMA observation of the surface of hybrid spherical microbead clearly showed where the TiO 2 particles were distributed. In addition, the extent of coverage by TiO 2 particles of the surface was also confirmed by external appearance, because the surface of cellulose/ TiO 2 hybrid spherical microbeads on which there were relatively few TiO 2 particles appeared dark yellow. In contrast, the cellulose/TiO 2 hybrid spherical microbeads on which TiO 2 particles aggregated densely appeared white. It was suggested that the distribution of TiO 2 particles on the hybrid spherical microbeads was related to electric repulsion between the CSS À group and TiO 2 . The narrower the zeta potential distribution of TiO 2 particles in the sphering pH condition (i.e., in pH 13 aqueous solution) is, the more TiO 2 particles were driven out from the cellulose xanthate domain.

Cellulose/boron nitride core–shell microbeads providing high thermal conductivity for thermally conductive composite sheets

“…We previously reported that the distribution of inorganic particles in composite spherical microbeads prepared by viscose phase separation method depends on the zeta potential of the particles surface. 21,22 The cellulose xanthate spherical droplet is produced by the electrostatic repulsion between the xanthate CSS À and SPA COO À groups. If the zeta potential of the inorganic particles in alkaline aqueous solution (viscose is a strong base) becomes negative and their charge distribution is narrow, the electrophoretic mobility of the inorganic particles becomes larger.…”

“…We (1) used core-shell spherical microbeads as a thermally conductive ller; (2) developed these cellulose/h-BN core-shell spherical microbeads using phase separation of a cellulose xanthate aqueous solution (viscose). Cellulose is reportedly hybridized with inorganic materials such as TiO 2 , 21,22 diamond, SiC, Al 2 O 3 , CeO 2 (ref. 23) and various pigments; 24 (3) hybridized the cellulose/h-BN core-shell microbeads with epoxy resin, using compression molding.…”

Synthesis and characterization of guar gum templated hybrid nano silica

“…Polysaccharides are reported to manipulate the formation of hybrid silica nanocomposites by sol-gel processes [7][8][9][10]. In the literature, different polysaccharides/mineral oxides are described such as cellulose/silica [11], alginate/silica [12] chitosan/silica [13][14][15][16], and cellulose/titania [17,18]. Conducting sol-gel chemistry in presence of biopolymer template furnishes hybrids which on calcination >450 • C results into porous materials.…”

Multifunctional Hybrid Materials From Poly(3‐Hydroxybutyrate), TiO2 Nanoparticles, and Chitosan Oligomers by Combining Electrospinning/Electrospraying and Impregnation

“…This is due to the fact that, from a technological point of view, the problem concerning the removal of reacted TiO 2 when it is applied in the form of suspensions has not been solved yet. In order to overcome this problem, a number of authors have incorporated TiO 2 in different polymer matrices in the form of spheres, layers, or films 7–11. Moreover, it has been found that composite films of PHB‐TiO 2 are effective in the sterilization and discoloration of methylene blue and rose bengal, and they are also biodegradable and environmentally friendly 12.…”