Study on the Granulation Behavior of TiO2-PVA Composite Powders Prepared Via Spray Drying Technique

Abstract

In this study, TiO 2-polyvinyl alcohol (PVA) composite granules were prepared via spray drying technique. To investigate the effects of solid content and binder/powder ratio in the slurry on the granulation behavior of TiO 2 powders, the feed compositions were designed to vary over a wide range. The morphology, actual densities, and average granule size and size distribution of the TiO 2-PVA composite granules were characterized by using scanning electron microscopy technique, a gas pycnometer, and an image analyzing program (Image-J), respectively. The results indicate that solid content and the amount of PVA in the feedstock slurry are the dominant factors determining the granule morphology, size, and size distribution of TiO 2-PVA composite. Moreover, it was observed that increasing the solid content and the amount of PVA in the slurry improved the granulation process and reduced the granule defects. For the preparation of spherical TiO 2-PVA composite granules with the minimum amount of non-granulated powders, the optimized composition of the feedstock slurry was found to be 35 wt.% solid and 3 wt.% PVA.

Controllable Fabrication of Monodisperse Poly(vinyl alcohol) Microspheres with Droplet Microfluidics for Embolization

“…21 Avcioglu et al prepared PVA powder particles by the spray drying method. 27 However, the sizes of PVA microspheres prepared by these two methods are not uniform. Microfluidic technology has unique advantages in the continuous production of droplets with controllable and uniform sizes by controlling the flow rates of fluids.…”

“…Poly­(vinyl alcohol) (PVA) has good biocompatibility , and elasticity, so it is the most commonly used material for fabricating embolic microspheres. − Currently, the methods for fabricating PVA microspheres mainly include emulsification, followed by chemical cross-linking, ,, spray drying, , freezing–thawing, , and microfluidic technology. − For example, Li et al dispersed PVA aqueous solution into the mixed solution of Span 80 and n -heptane by stirring to form water-in-oil droplets and then added glutaraldehyde (GA) as a chemical cross-linking agent to prepare PVA microspheres . Avcioglu et al prepared PVA powder particles by the spray drying method . However, the sizes of PVA microspheres prepared by these two methods are not uniform.…”