Study On Morphology, Molecular Weight And Thermal Properties Of Composite Microspheres Prepared By Controlling Feeding Ways And Reaction Time

The application of composite microspheres closely lies on their morphology and properties. In this work, carbon nanotubes (CNTs) reinforced composite microspheres were prepared via in situ polymerization: methyl methacrylate was selected as matrix to copolymerize with cationic comonomer 2-(methacryloyloxy)ethyltrimethyl ammonium chloride, using CNTs as nanofillers to fabricate composite microspheres. The morphology, molecular weight, and thermal properties of obtained composite microspheres with different monomer feeding ways (batch polymerization and dropwise monomer feeding procedure) and reaction time (1-6 h) were investigated. The results revealed that dropwise monomer feeding procedure leaded to remarkably decreased diameter of composite microspheres. Compared with polymer microspheres, the addition of CNTs resulted in earlier formation of composite microspheres. When the reaction time was controlled for 1-6 h, the morphology of the composite microspheres underwent a shape change from deformed particles to spherical structure. Although reaction time had no significant effect on molecular weight, the thermal property was gradually improved with increase of reaction time. For ensuring the effectiveness of the produced composite microspheres and tailoring them for any specific application, our investigation shows significant reference value on choosing feeding ways and controlling reaction time to obtain different morphology microspheres. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45741.