Studies on Some Quality Parameters of the Nigerian Polymer and Paper Bank Notes

Abstract

There is no doubt that in Nigeria, the change to mis-using and counterfeiting of the paper bank notes have given cause for concern by the Central Bank of Nigeria (CBN), prompting the introduction of the polymer bank notes to address some of these problems. This research work investigates the physico-mechanical properties of samples of Nigerian polymer and paper bank notes of N5, N10, N20 and N50 denominations for quality parameters such as sizes, sorption rates, tear and tensile strengths, wet and dry rubfastness testing on standard Grey Scales ratings as well as microbial loads. The results showed that polymer notes have sizes of 131.0 x 72mm/0.7 on the average compared to 150.0 x 72mm/0.8 for paper for all the sample denominations. Tensile strength determinations on a Standard Organization of Nigeria (SON),s Stable Micro-System (SMS) Tensometer 5011 indicates 122.64Nmm-2±2 mean for both polymer and paper while tear strength measurements on Elmendarf 2000 tear testing Machine showed a mean value of 6341.2N±3.0 for polymer as against 3223.8N±5.0 for paper. Rubfastness testings indicate that polymer notes have ratings of 4/5(wet condition) and 5 (dry condition) compared to 1(wet condition) and 2(dry condition) for paper. Sorption rates (% Swelling Indices) in selected polar and non- solvents (liquids) were carried out as well as microbial loads and the results are reported in this paper. Generally, the results showed that polymer notes exhibit far superior physico- mechanical properties with very low coliform count compared to paper notes.