Nondestructive testing of defects in adhesive joints

is shown in table 2. Curcumin addition substantially increased the tensile strength and modulus of the
resultant system. A considerable decrease in the fracture strain is observed with curcumin loading.
Results indicate that curcumin acts as a reinforcing agent in EVA matrix. Effect of tensile strength on
short term ageing of EVA and curcumin loaded EVA in PBS is shown in figure 3. The system tends
to be stable during ageing except for that containing 10wt% curcumin. Contact angle data obtained for
EVA and curcumin loaded EVA shows no significant changes in contact angle data with curcumin
loading (figure 4). Matrices exhibited increase in water uptake with higher curcumin loadings. Water
uptake behavior is shown in figure 5 with respect to curcumin content in the EVA matrix. Increases in
curcumin content increased water uptake by the polymer matrix.
3.2. Elution profile of curcumin
Cumulative release of curcumin from EVA40 is shown in figure 6. Different concentrations
of curcumin were loaded in the matrix and release was monitored upto 15days. The quantity of
curcumin released is a function of curcumin loaded in the matrix.
Conclusion
EVA copolymer is found to be a suitable system for the sustained release of curcumin.
Curcumin released from the matrix depended on the quantity of curcumin loaded in it.
References
1. International Cardiovascular Disease Statistics, American Heart Association, 2007.
2. Express Healthcare Management, Indian Express Newspapers Ltd., India, 2001.
3. Gupta R, Misra A, Pais P, Rastogi P, Gupta VP. International Journal of Cardiology 2006; 108 (3):
291-300.
4. Boehm M and Nabel EG. Progress in Cell Cycle Research; 2003; 5; 19-30.
5. Pan CJ, Tang JJ, Shao ZY, Wang J and Huang N. Colloids and Surfaces B: Biointerfaces 2007;
59 (1):105-111.
6. Pan CJ, Tang JJ, Weng YJ, Wang J, Huang N. Journal of Controlled Release 2006; 116(1): 42-49.
7. Guo Q, Guo S, Wang Z. Journal of Controlled Release 2007:118(3):318-324.
8. Tambe S, Singh SK, Patri M, Kumar D. Progress in Organic Coatings 2008;62 (4):382-386.
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Table 1. Mechanical Properties of EVA grades
Polymer grade
Tensile strength
(MPa)
Elongation at
break (%)
Modulus
(MPa)
EVA -12 11.97 ± 0.99 2790 ± 207 5.28 ± 0.61
EVA -18 8.44 ± 0.54 1183 ± 92 19.97 ± 2.19
EVA -28 13.50 ± 1.19 1723 ±129 5.00 ± 1.37
EVA -40 8.81 ± 0.20 2610 ± 97 0.56 ± 0.05
4