Positron annihilation lifetime spectroscopy study on epoxy moisture absorption

16th International Conference on Positron Annihilation

Gordo, P.M.^1 ; Luis, J.M.M.^1 ; Marques, M. F. Ferreira^1,2 ; Naia, M. Duarte^3 ; Morais, J.J.M.^4

CEMUC, Department of Physics, Coimbra University, 3004-516 Coimbra, Portugal^1

Department of Chemical and Biological Engineering, ISEC-IPC, R. Pedro Nunes, Quinta da Nora, 3030-199 Coimbra, Portugal^2

CEMUC, Department of Physics, ECT-UTAD, PO Box 1013, 5001-801 Vila Real, Portugal^3

CITAB, Department of Engineering, ECT-UTAD, PO Box 1013, 5001-801 Vila Real, Portugal^4

关键词: Absorption process;    Effect of water;    Exposed to;    Exposure-time;    Gravimetric measurements;    Moisture absorption;    Positron annihilation lifetime spectroscopy;    Water molecule;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/443/1/012055/pdf
DOI  :  10.1088/1742-6596/443/1/012055

来源: IOP

【 摘 要 】

Positron annihilation lifetime spectroscopy was used to study the effect of water uptake on the free volume of a commercial epoxy exposed to atmospheres with relative humidity ranging from 30.5% to 95.8%. The absorption process was also analyzed by gravimetric measurements. When exposed to humidity the mean hole volume remains constant and the number of holes not occupied by water molecules decrease with increasing of both the exposure time and the relative humidity as indicated by the constancy of τ3and the decrease of I3.