Polyearbonate (PC) was blended with acrylic impact modifiers (AIMS). The effects of modifiers weight fraction on the Izod impact strength and yield strength of PC/AIM blends were investigated. The samples with 4% modifiers were aged under the T-g of PC in an air-circulating oven, and the effects of aging time on impact strength, yield strength, modulus, elongation at break, post yield stress drop (PYSD) values, and morphology of fracture surface were investigated. The effects of aging time on the shape of stress-strain curve were also investigated. The aged samples were heat-treated over the T-g of PC to erase the effects of physical aging. It was found that the drop of impact strength caused by physical aging can be recovered, the increment of yield strength and PYSD value caused by physical aging can only be partly recovered, and the heat-treatment over the T-g of PC caused further increment of modulus. (c) 2005 Wiley Periodicals, Inc.