Size Distributions of Mesophase Microbeads Obtained from Heterogeneous and Homogeneous Systems

Abstract

Mesophase microbeads were prepared by thermal condensation in the presence of heterogeneous and homogeneous systems. Morphologies and sizes of mesophase microbeads are characterized by scanning electronic microcopy (SEM), polarized light optical microphotography (PLOM) and laser particle size analyzer. SEM and PLOM results exhibit that mesophase microbeads have a narrow size distribution and many large particle in heterogeneous system. In homogeneous system, there are a great deal of smaller mesophase microbeads and a very little of larger mesophase microbeads. The laser particle size analysis results show that size distribution of mesophase microbeads in heterogeneous system is quite different from that in homogeneous system. There are multi-peaks on volume distribution curve in heterogeneous system. Larger mesophase microbeads are mainly in tens micron peak of size distribution curve. In homogeneous system, particle size of mesophase microbeads has a wide distribution and only single peak on size distribution curve. Moreover, sulfur concentration in reaction system makes the size of mesophase microbeads increase and the size distribution curve move to larger particle diameter. But sulfur concentration can not affect the curve pattern of size distribution.