Search

Particle size and its distribution are one of the main characteristics of polymers produced by suspension polymerization, which determines the final properties of the product. Poly (vinyl pivalate) (PVPi) microspheres having various particle sizes and uniform particle-size distributions are promising precursors of poly (vinyl alcohol) embolic materials, which can be introduced through catheters in the management of gastrointestinal bleeders, arteriovenous malformations, hemangiomas, and traumatic rupture of blood vessels. To prepare PVPi, vinyl pivalate was suspension-polymerized using a low temperature initiator, 2,2′- azobis (2,4-dimethylvaleronitrile), and the effects of polymerization conditions were investigated in terms of the size and size distribution of suspension particles. The particle size distributions of polymerized particles were measured with a laser diffraction analyzer. In this study, particle size and its distributions have been measured by varying some operating conditions including stirring speed, water-to-monomer molar ratio, and suspending agent concentration. The surface morphology of the PVPi microsphere was investigated using a scanning electron microscope (JSM 5800-LV, Jeol, Japan) with a magnification of 200x. [ABSTRACT FROM AUTHOR]