Accession Number : AD0722057

Title :   Aromatic Solute Molecular Ion and Triplet State Formation in Polystyrene and Polymethylmethacrylate,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Siegel,Seymour ; Stewart,Thomas B.

Report Date : 15 JAN 1971

Pagination or Media Count : 61

Abstract : Solutions of naphthalene-d8 and N,N,N',N' tetramethyl-p-phenylenediamine (TMPD), singly and in combination, in polystyrene (PS) and polymethylmethacrylate (PMMA) were irradiated by 1.9-MeV electrons at 86K. The irradiation pulse had a half width of 0.7 sec. Examination of the absorption spectra of samples immediately after the irradiation pulse indicated that solute triplet state molecules and positive ion molecules were produced, with TMPD as the solute in both polymer hosts. With naphthalene, positive ions were observed only in PMMA, whereas triplet state molecules were observed in both polymers. Analysis of the data from the mixed solute samples indicates that the presence of 0.05-M TMPD captures all of the mobile positive charge, even when the naphthalene concentration is as high as 0.2 M. The radiation yields of triplets and ions in the two polymers are discussed and compared. PMMA is just as effective as PS in producing triplet excited states of the aromatic solute in terms of limiting yields at high solute concentration, but the concentration dependence is different in the two polymers. Deductions were made with regard to charge capture and migration in these systems. (Author)

Descriptors :   (*AROMATIC COMPOUNDS, *ELECTRON IRRADIATION), (*MOLECULAR ORBITALS, ELECTRON IRRADIATION), NAPHTHALENES, AMINES, DEUTERIUM COMPOUNDS, RADIATION CHEMISTRY, ACRYLIC RESINS, STYRENE PLASTICS, EXCITATION

Subject Categories : Radiation and Nuclear Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE