Positron studies of the temperature-dependence of free volumes in Polydimethylsiloxane/poly(propylene oxide) urethane/urea membranes

Radiation Physics and Chemistry

Volumn 76, Issue 2, 2007, Pages 129-133

  Ferreira Marques, M F ^a,b   Gordo, P M ^b   Kajcsos, Zs ^c   Lopes Gil, C ^b   de Lima, A P ^b   Queiroz, D P ^d   de Pinho, M N ^d  

^a POLYTECHNIC INSTITUTE OF COIMBRA   (Portugal)

^b UNIVERSITY OF COIMBRA   (Portugal)

^c WIGNER RESEARCH CENTRE FOR PHYSICS   (Hungary)

^d INSTITUTO SUPERIOR TÉCNICO   (Portugal)

Author keywords

Doppler broadening; Free volume; Lifetime; Membranes; Permeability; Phase separation; Positronium

Indexed keywords

DOPPLER EFFECT; OXIDES; PHASE SEPARATION; POLYPROPYLENE OXIDES; POLYURETHANES; SILICONES; UREA;

FREE-VOLUME; LIFETIME; PERMEABILITY; POSITRONIUM;

POLYMERIC MEMBRANES;

DIMETICONE; POLY(PROPYLENE OXIDE)URETHANE; POLYMER; UNCLASSIFIED DRUG; UREA;

ARTICLE; DOPPLER FLOWMETRY; FILM; GAS PERMEABILITY; PHYSICAL PHASE; POSITRON; STRUCTURE ANALYSIS; TEMPERATURE DEPENDENCE;

EID: 33751170681     PISSN: 0969806X     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.radphyschem.2006.03.017     Document Type: Article

References (17)

1. Dlubek G., Fretwell H.M., and Alam M.A. Positron/positronium annihilation as probe for the chemical environment of free volume holes in polymers. Macromolecules 33 (2000) 187-192
2. Dlubek G., Stejny J., Lüpke T.H., Bamford D., Petters K., et al. Free-volume variation in polyethylenes of different crystallinities: positron lifetime, density and X-ray studies. J. Polyn. Sci.: Part B: Poly. Phys. 40 (2002) 65-81
3. Eldrup M., Lightbody D., and Sherwood J.N. The temperature dependence of positron lifetimes in solid pivalic acid. Chem. Phys. 63 (1981) 51-58
4. Ferreira Marques M.F., Lopes Gil C., Gordo P.M., de Lima A.P., Kajcsos Zs., Queiroz D.P., and de Pinho M.N. Studies in polyurethane membranes by positron annihilation spectroscopy. Radiat. Phys. Chem. 68 (2003) 573-576
5. Ferreira Marques M.F., Gordo P.M., Lopes Gil C., de Lima A.P., Placco Queiroz D., de Pinho M.N., Kajcsos Zs., and Duplâtre G. Gas permeability and temperature-dependent free-volume studies in polyurethane membranes by positron lifetime and doppler spectroscopies spectroscopies. Mater. Sci. Forum 445-446 (2004) 289-291
6. Gidley D.W., Frieze W.E., Yee A.F., Ryan E.T., and Ho H.M. Positronium annihilation in mesoporous thin films. Phys. Rev. B 60 8 (1999) R5157-R5160
7. Goworek T., Ciesielski K., Jasińska B., and Wawryszczuk J. Temperature variations of average o-Ps lifetime in porous media. Radiat. Phys. Chem. 58 (2000) 719-722
8. Ioan S., Grigorescu G., and Stanciu A. Effect of segmented poly(ester-siloxane)urethanes compositional parameters on differencial scaning calorimetry and dynamic-mechanical measurements. Polymer 38 (2002) 2295-2303
9. Jean, Y.C., 1993. Caracterizing free volumes and holes in polymers by positron annihilation spectroscopy. In: Advances with Positron Spectroscopy of Solids and Surfaces, NATO, Advanced Research Workshop, pp. 563-580.
10. Jean Y.C., et al. In: Jean Y.C., Mallon P.E., and Schrader D.M. (Eds). Principles and Applications of Positron & Positronium Chemistry (2003), World Scientific, Singapore 253-277
11. Kansy J. Microcomputer program for analysis of positron annihilation lifetime spectra Nucl. Instrum. Methods in Phys. Res. A 374 2 (1996) 235-244
12. Liszkay L., Corbel C., Baroux L., Hautojärvi P., Bayhan M., Brinkamn A.W., and Tatarenko S. Positron trapping at divacancies in thin polycrystalline CdTe films deposited on glass. Appl. Phys. Lett. 64 (1994) 1380-1382
13. Maurer F.H.J., and Schmid M. Some remarks on the relation between free-volume fractions and ortho-positronium lifetimes in amorphous polymers. Radiat. Phys. Chem. 58 (2000) 509-512
14. Nakanishi H., Wang S.J., and Jean Y.C. Microscopic surface tension studied by positron annihilation. In: Sharma S.C. (Ed). Positron Annihilation Studies of Fluids (1987), World Scientific, Singapore 292-298
15. Queiroz D.P., and Pinho M.N. Structural characteristics and gas permeation properties of polydimethylsiloxane/poly(propylene oxide) urethane/urea bi-soft segment membranes. Polymer 46 (2005) 2346-2353
16. Tao S.J. Positronium annihilation in molecular substances. J. Chem. Phys. 56 11 (1972) 5499-5510
17. Vlad S., Vlad A., and Oprea S. Interpenetrating polymer network based on polyurethane and polysiloxane. Euro. Polym. J. 38 (2002) 829-835