Effect of γ Irradiation on Latex Film Dissolution

✍ Scribed by K. Aydin; Ş. Uǧur; Ö. Pekcan

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 129 KB
• Volume: 233
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.2000.7151

✦ Synopsis

Latex films have been prepared by annealing pyrene (Py)-labeled poly(methyl methacrylate)-polyisobutylene particles at the glass transition temperature (100 • C). These films were then irradiated by γ rays from 60 Co in a γ cell at room temperature at various dose rates (rad/h). Before dissolution the films were annealed at 200 • C for a 30 min time interval to complete the film formation process. Steady-state fluorescence techniques were used to monitor the dissolution of irradiated latex films. Dissolution of films in a chloroform-heptane (80%-20%) mixture was monitored in real time by the Py fluorescence intensity change. Relaxation constants, k 0 , and dissolution coefficients, D d , of polymer chains were measured. Two different regimes of D d values were observed during dissolution, which are related to two different molecular weight distributions caused by scission and branching of polymer chains when they were irradiated and annealed.