Effect of Molding Condition on Mechanical Properties of Injection Molded Nylon 6-Clay Nanocomposites

Abstract

In this study, the effects of varying molding conditions, including melt temperature, mold temperature, and injection speed, on the mechanical properties of injection molded nylon-6/fluoromica nanocomposite (Unitika) were investigated. A DSC test and SEM were used to examine the microstructure of material and verify the experimental results. Results showed that the addition of 5 wt% nano-fluoromica particles to pure nylon-6 increases the tensile strength over 20% and the flexural strength more than 38%, but decreases impact strength by less than 2%. Results also indicate that the tensile strength and flexural strength of the nylon-6/fluoromica nanocomposite increase with increased melt temperature, mold temperature, and injection speed. However, the impact strength of nylon-6/fluoromica nanocomposite increased with increased melt temperature, but decreased with increasing mold temperature and injection speed. The DSC measurement revealed that the crystallinity of nylon-6/fluoromica nanocomposite increases with all molding parameters. The SEM results also indicate that the nylon-6/fluoromica nanocomposite is more brittle than the pure nylon-6.

Keywords

nylon-6/fluoromica nanocomposite tensile strength flexural strength impact strength.

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