A MALDI, TGA, TG/MS, and DEA study of the irradiation effects on PMMA

• Published in: Polymer (Guilford) Vol. 44; no. 1; pp. 167 - 176
• Main Authors: Tatro, S.R., Baker, G.R., Bisht, K., Harmon, J.P.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2003; Elsevier
• Subjects: Applied sciences; Crosslinking and degradation; Exact sciences and technology; Matrix assisted laser desorption/ionization; Physicochemistry of polymers; Poly(methyl methacrylate); Polymers and radiations; Radiation; Matrix assisted laser desorption/ionization; Poly(methyl methacrylate); Radiation; Coupled method; Thermogravimetry; Methyl methacrylate polymer; Experimental study; Syndiotactic polymer; Dielectric relaxation; Radiation dose; Gamma radiation; Investigation method; Reaction mechanism; Radiochemical degradation; Mass spectrometry
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(02)00727-9

Poly(methyl methacrylate) (PMMA) ( M w=6.4×10 3, PD=1.06) was irradiated under vacuum. The constant dose rate was 1.66×10 4 rad/min at doses between 10 and 100 Mrad using a cobalt-60 source. The samples were then analyzed by matrix assisted laser desorption/ionization (MALDI), hyphenated thermogravimetric/mass spectrometry (TG/MS), and dielectric analysis (DEA), all novel methods for the analysis of polymers damaged by radiation. Gel permeation chromatography (GPC), nuclear magnetic resonance (NMR), and differential scanning calorimetry (DSC) were also used for analysis. This study evidenced main chain scission, the removal of ester side groups, and the production of monomer as a result of ionizing radiation.