Mechanical Properties of Silas-Balloon Filled Polystyrene Composites

Abstract

The mechanical properties of polystyrene composites filled with hollow, spherical Silas balloons were investigated. Three different grades of Silas balloons were used in this study: Grade S with the diameter ranging from 74 to 149μ, Grade M from 149 to 259μ and Grade L from 259 to 590μ. The tensile, flexural and compressive strengths as well as moduli were determined as a function of filler content by using an universal tensile testing instrument.The tensile, compressive and flexural strengths of the composites decreased with increasing the filler content. However, since the density of the composites also decreased with increasing the filler content, the specific strengths of the composites with Grade S Silas balloons showed little change from their original strengths even though the filler content was varied. As for the moduli of elasticity under tension, compression and flexure, the composites containing Grade S Silas balloons with or without silan-treatment showed increase in these moduli with increasing the filler content.The glass microballoons were also used to make composites with polystyrene resin and the mechanical properties of these composites were compared with those of the composites containing Grade S Silas balloons with or without silan-treatment. The ones with Silas balloons had the mechanical properties equivalent or superior to the ones with glass microballoons, when compared on a volume % basis.The effect of adhesion between polystyrene and Silas balloons was studied by using both untreated and silan-treated (coupling agent: UCC A-1120) Grade S Silas balloons. The nature of the fracture surface was examined with a scanning electron microscope. The tensile and flexural strengths as well as elastic moduli of the composites were improved when the adhesive force of fillers became stronger.