Positron Annihilation Characterization of TiO₂ Doped Polystyrene

Abstract:

TiO₂ doped polystyrene thin films fabricated by solution cast method. The effect of dopant concentrations has been studied for the structural, morphological, optical and defects properties. The XRD results revealed that the degree of crystallinity remains largely invariant due to the presence of the polymer. Interesting results have been obtained from optical measurement which depicted that there is increase in UV-shielding efficiency with the increase in the dopant concentration as the absorbance was found to be maximum in case of UV region. Surface morphology of the films shows a rod like structure for 0.25 wt% of TiO₂, while for higher concentrations the TiO₂ clusters were obtained. The positron lifetime results reveal that the free volume hole concentration decreased with the increase in TiO₂ concentration as intensity of o-positronium decreases with the increase in concentration of TiO₂ doping.

• Periodical: Materials Science Forum (Volume 771)
• Pages: 169-177
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.771.169
• Online since: October 2013
• Authors: Aman Deep Acharya
• Keywords: Polystyrene Thin Films, Positron Annihilation, Solution Cast Method, TiO₂

References

[1] B. Heinemann, Stoneham, M. Achusetts, Physics of polymer surfaces and interfaces, Isaac Sanchez (Eds.), the University of Michigan, 1992, p.336.

[2] D.L. Allara, S.V. Atre, A.N. Parikh, Polymer surfaces and interfaces II, edited by W.J. Feast, H.S. Munrom, and R.W. Richards (Eds.), John Wiley & Sons, Chichester, 27, 1993, p.314.

[3] H. M. Zidan, M. Abu-Elnader, Structural and optical properties of pure PMMA and metal chloride-doped PMMA films, Physica B 355 (2005) 308-317.

DOI: 10.1016/j.physb.2004.11.023

[4] T. Podgrabinski, E. Hrabovska, V. Svarcik, Characterization of polystyrene and doped polymethylmethacrylate thin layers, J. Mater. Sci.: Mater. In Elec. 16 (2005) 761-765.

DOI: 10.1007/s10854-005-4980-7

[5] P. Liu, Facile preparation of monodispersed core/shell zinc oxide@polystyrene (ZnO@PS) nanoparticles via soapless seeded microemulsion polymerization, Colloids Surfaces A, 291 (2006) 155-161.

DOI: 10.1016/j.colsurfa.2006.05.007

[6] N. Nakayama, T. Hayashi, Preparation and characterization of TiO2 and polymer nanocomposite films with high refractive index, J. Appl. Polym. Sci. 105 (2007) 3662- 3672.

DOI: 10.1002/app.26451

[7] T. J. Dawidczyk, M. D. Walton, W. S. Jang, J. C. Grunlan, Layer-by-layer assembly of UV-resistant poly(3,4-ethylenedioxythiophene) thin films, Langmuir 24 (2008) 8314-8318.

DOI: 10.1021/la800967x

[8] T. Kyprianidou Leodidou, P. Margraf, W. Caseri, U. W. Suter, P., Walther, Polymer sheets with a thin nanocomposite layer acting as a UV filter, Polym. Adv. Technol. 8 (1997) 505-512.

DOI: 10.1002/(sici)1099-1581(199708)8:8<505::aid-pat678>3.0.co;2-u

[8] C. L. Lu, J. F. Gao, Y. Q. Fu, Y. Y. Du, Y. L. Shi, Z. M. Su, A Ligand Exchange Route to Highly Luminescent Surface-Functionalized ZnS Nanoparticles and Their Transparent Polymer Nanocomposites, Adv. Funct. Mater. 18 (2008) 3070-3079.

DOI: 10.1002/adfm.200800452

[10] A. R. Gandhe, J. B. Fernandes, Methylation of phenol over Degussa P25 TiO2, J. Mol. Catal. A : Chem. 226 (2005) 171.

DOI: 10.1016/j.molcata.2004.10.035

[11] Krishnan, N. Venugopalan Pillai, V. P. Mahadevan. Pillai, R. Philip, Effect of cadmium oxide incorporation on the microstructural and optical properties of pulsed laser deposited nanostructured zinc oxide thin films, Mater. Chem. Phys, 121 (2010) 406-413.

DOI: 10.1016/j.matchemphys.2010.01.004

[12] V. P. Shantarovich, On the role of free volume in pick-off annihilation and positronium chemical reactions. J. Radiational. Nucl. Chem. 210 (1996) 357-369.

DOI: 10.1007/bf02056378

[13] S. Tao, Positronium annihilation in molecular substances, J. Chem. Phys, 56 (1972) 5499-5510.