The Malaysian Journal of Analytical Sciences Vol 15 No 1 (2011): 81 – 92

 

 

 

IMPROVEMENT OF THE PHOTOSTABILIZATION OF PVC FILMS IN THE PRESENCE OF THIOACETIC ACID BENZOTHIAZOLE COMPLEXES

 

Emad Yousif^1*, Jumat Salimon², Nadia Salih²

 

¹Department of Chemistry,

College of Science, Al-Nahrain University, Baghdad, Iraq

²School of Chemical Sciences and Food Technology,

Faculty of Science and Technology, Universiti Kebangsaan Malaysia,

43600 Bangi, Selangor, Malaysia

 

*Corresponding author: emad_yousif@hotmail.com

 

 

Abstract

The photostabilization of poly(vinyl chloride) (PVC) films by 2-thioacetic acid benzothiazol with Sn(II), Cd(II), Ni(II), Zn(II) and Cu(II) complexes was investigated. The PVC films containing concentration of complexes 0.5% by weight were produced by the same casting method from tetrahydrofuran (THF) solvent. The photostabilization activities of these compounds were determined by monitoring the carbonyl, polyene and hydroxyl indices with irradiation time. The changes in viscosity average molecular weight of PVC with irradiation time were also tracked (using THF as a solvent). The quantum yield of the chain scission (φ_cs) of these complexes in PVC films was evaluated and found to range between 4.71´10^-8 and 8.98´10^-8. Results obtained showed that the rate of photostabilization of PVC in the presence of the additive follows the trend:

 

Sn(L)₂ > Cd(L)₂ > Ni(L)₂ > Zn(L)₂ > Cu(L)₂

 

According to the experimental results obtained, several mechanisms were suggested depending on the structure of the additive. Among them HCl scavenging, UV absorption, peroxide decomposer and radical scavenger for photostabilizer additives mechanisms were suggested.

 

Keywords: Photostabilizer, PVC, 2-Thioacetic benzothiazol acid.

 

References

1.       Saeki, Y., Emura, T. 2002. Technical progresses for PVC production. Prog. Polym. Sci. 27: 2055–131.

2.       Braun, D., 2004. Poly(vinyl chloride) on the way from the 19th century to the 21st century. J. Polym. Sci. A Polym. Chem. 2004;42: 578–586.

3.       Moulay, S., 2010. Chemical modification of poly(vinyl chloride)-Still on the run.  Progress in Polymer Science. 35: 303-331.

4.       Andrady, A., Hamid, S., Hu, X. & Torikai, A. 1998. Effects of increased solar ultraviolet radiation on materials. Journal of Photochemistry and photobiology B-Biology. 46: 96-103.

5.       Gardette, J., Gaumet, S. & J. L. Philippart, J. 1993. Influence of the experimental conditions on the photooxidation of poly(vinyl chloride). Journal of Applied Polymer Science. 48(11): 1885-1895.

6.       Yousif, E., Farina, Y., Kasar, K., Graisa, A. & Ayid. K. 2009. Complexes of 2-thioacetic acid benzothiazole with Some Metal Ions. American Journal of Applied Sciences. 6(4): 605-608.

7.       Rasheed, R., Mansoor H., Yousif E., Hameed A. FarinaY. & Graisa A., 2009. Photostabilizing of PVC films by 2-(aryl)-5-[4-(aryloxy)-phenyl]-1,3,4-oxadiazole compounds. European Journal of Scientific Research. 30(3): 464-477.

8.       Rabek, J. & Ranby, B. 1975. Photodegradation, photooxidation and photostabilization of Polymers, John Wiley,  New York.

9.       Mark, J. 2007. Physical properties of polymers handbook. Springer, New York.

10.    Nakajima, N., Sadeghi, M., Kyu, T. 1990. Photodegradation of poly(methyl methacrylate) by monochromatic light: quantum yield, effect of wavelengths, and light intensity. Journal of Applied Polymer Science. 41: 889 – 1363.

11.    Andrady, A., Searle, N. 1989. Photodegradation of rigid PVC formulations. II. Spectral sensitivity to light-induced yellowing by polychromatic light. Journal of Applied Polymer Science. 37:2789-2802.

12.    Mori, F., Koyama, M. & Oki, Y. 1977.  Studies on photodegradation of poly(vinyl chloride) (part 1). Die Angewandte Makromolekulare Chemie. 64(1): 89-99.

13.    Shyichuk, A. & White, J. 2000. Analysis of chain-scission and crosslinking rates in the photo-oxidation of polystyrene. Journal of Applied Polymer Science. 77(13): 3015-3023.

14.    Jellinek, H. 1978. Aspects of degradation and stabilization of polyolefines, Elsevier, Amsterdam.

15.    Yousif, E., Aliwi, S., Ameer, Ukal, J. 2009. Improved photostability of PVC films in the presence of 2-thioacetic acid -5-phenyl-1,3,4-oxadiazole complexes. Turkish Journal of Chemistry. 33: 399-410.

16.    Yousif, E., Salih, N., Salimon, J. 2011. Improvement of the " Improvement of the Photostabilization of PVC Films in the Presence of 2N-Salicylidene-5-(Substituted)-1,3,4-Thiadiazole. Journal of Applied Polymer Science. 120: 2207–2214.

17.    Adil, H., Emad Yousif, E., Salimon, J. 2011. New Stabilizers For PVC Based On Benzothiazole Complexes. LAMBERT Academic Publishing, Germany.

18.    Yousif, E., Hameed, A., Rasheed, R., Mansoor, H., Farina, Y., Graisa, A., Salih, N., Salimon, J. 2010. Synthesis and Photostability Study of Some Modified Poly(vinyl chloride) Containing Pendant Benzothiazole and Benzimidozole Ring. International Journal of Chemistry, 2(1): 65-80.