Abstract
In order to improve the toughness of silica filled acrylic composite, two typical impact modifiers, multi-layer core/shell particle and polymerisable elastomer, were examined. The IZOD impact strength of the composite was not affected by the core/shell particle, while significant improvement was observed in the elastomer modification. The difference was detected at the fracture surface by scanning electron microscope (SEM) observation and elemental analysis which was given by energy-dispersed X-ray micro-analyzer equipped with the SEM (SEM-EDX) . The result suggested that the curable elastomer transferred the destruction phase from silica/matrix interface to inside of the matrix. The major contribution of the elastomer for this transfer was thought to be adhesion promotion at silica/PMMA interface, while the core/shell particle toughened the matrix only. Consequently, the elastomer modified acrylic composite was toughened farther by core/shell particle very efficiently, because the destruction occurred in the toughened matrix phase. The concept for toughening in silica filled acrylic composite was provided through this work, and the effective toughening method was proposed.
