Microspheres as potential fillers in composite polymeric materials

Abstract

Microspheres used in our work were acquired from one of Kazakhstan coal-fueled power plant. The size of the microspheres varied between 45 and 400 μm, the median particle size (D50) was 158 μm. Microscopic analysis revealed that the material consisted mainly of cenospheres. The results of elemental and oxide analysis showed that microspheres were composed of aluminosilicates. Identified crystalline phases were mullite (approx. 12 %) and trace amount of quartz (silica). Microscopic observations of the cross-sectional surface of both unmodified PUR foam and foams modified with microspheres showed a well formed, cellular structure of all materials. The observed cells are polyhedron in shape, most of them are closed, microspheres were uniformly distributed within polymer matrix and placed between cells. The apparent densities calculations of the samples showed that when microspheres were added to the polymer matrix, apparent density of the resulting composite materials increased. The results of elemental analysis pointed out the highest content of all three elements in unmodified PUR foam sample. The addition of the microspheres to the system resulted in decrease of the concentration of all three elements.

Fly Ash as an Eco-Friendly Filler for Rigid Polyurethane Foams Modification

“…The well-formed cellular structure can be seen on the cross-section of a reference sample. The observed cells were polyhedron in shape, uniform (SD values were small and did not exceed 8% of the average values), most of them were closed, which is an important characteristic influencing thermal insulation properties of the PUR foams [ 32 , 38 , 39 ].…”

“…The most frequently studied fillers used in PUR materials are mainly flame-retardant additives. There are a few publications that related to the use of FA and M in the PUR modifications [ 18 , 31 , 32 ]. Therefore, the research topic discussed in this article is innovative and there are no published research results in this field.…”

Study on the Compressive Strength and Water Absorption Characteristics of Mortar Blocks with Cenosphere as Partial Replacement for Cement

“…Baduge et al [7] used three types of cenosphere and reported that cenosphere is a sustainable alternative for lime binder and cement binder. The spherical shape of cenosphere increases the workability and the shrinkage resistance of cementious mix [8,9].…”