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 sola r 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 prope rties of PMMA and their change with aging time. Analysis of chemical modifi cation and structural change were performed by means of Fourier transformed infrared spectrophotometry (FTIR). The spectra confirmed that the aging pr ocess is initially promoted by hydrogen abstraction producing chain breakin g and formation of the carbon-carbon non-saturated bonds and shorter macrom olecular chains, such as vinyl, vinylidene and methyl. Calorimetric measure ments of samples by differential scanning calorimetry (DSC) detected change s of glass transition temperatures. Finally, the fracture toughness was mea sured by tensile test measurements. The toughness decreased similar to 40% after 1570 h. (C) 2001 Elsevier Science B.V. All rights reserved.