Properties of PMMA artificially aged

We report the effects of artificial aging poly(methyl methacrylate) (PMMA). The aging of samples was performed using a xenon-are lamp to simulate solar radiation. The maximum time of artificial aging was 1570 h, equivalent to 750 days of solar exposure. The purpose of this work is to study the properties of PMMA and their change with aging time. Analysis of chemical modification and structural change were performed by means of Fourier transformed infrared spectrophotometry (FTIR). The spectra confirmed that the aging process is initially promoted by hydrogen abstraction producing chain breaking and formation of the carbon-carbon non-saturated bonds and shorter macromolecular chains, such as vinyl, vinylidene and methyl. Calorimetric measurements of samples by differential scanning calorimetry (DSC) detected changes of glass transition temperatures. Finally, the fracture toughness was measured by tensile test measurements. The toughness decreased similar to 40% after 1570 h. (C) 2001 Elsevier Science B.V. All rights reserved.