Preparation of pigment-polymer hybrid particles for plastic colorants by dry-impact blending method

Abstract

Dry-impact blending method was employed to prepare hybrid particles composed of fine particles of phthalocyanine blue and a coarse particle of low-density polyethylene (LDPE). A simple mixing in a Henschel-type batch mixer of the two kinds of particles, which were largely different in the size, in ambient temperature applying high stress, produced hybrid particles, where the fine particles are distributed on the surface of the core particle. The surface appearances and the cross-sectional views of the particles were observed by scanning and transmission electron microscopy. It was revealed that the hybrid particles exhibited a capsule formation with the LDPE core coated with the phthalocyanine layer, where the phthalocyanine fine particles were embedded in the LDPE core particles. The hybrid particles thus prepared helps fine dispersion of the pigment into the LDPE matrix, and the pigmented LDPE sheet shows excellent color quality. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1762–1772, 1999