4.1. UV–vis analysis of SNP
Fig. 2 shows the UV–vis absorption peak of the silver
nanocolloid, graph 2(a) is the absorption peak of silvernanocolloid after 14 days of initial synthesis, whereas graph
2(b) shows the absorption peak of silver nanocolloid after
90 days of the initial experiment. This is the silver nanocolloid
which was used to make the nanosilver based
natural rubber latex foam. It can be clearly seen that the
maximum single absorption peak at 429.1 nm did not
change even after 90 days of initial synthesis of silver
nanocolloid by the citrate reduction method. The pH value
of the resultant silver nanocolloid was 10 and it also did not
affect the stabilizing system of natural rubber latex. In the
compounding process of making foam rubber from natural
rubber latex, all the mixing ingredients should be basic and
they should not affect the latex stabilizing system [27].
Since the pH value of the centrifuged latex used in the
synthesis process was 10, the other ingredients used in the
synthesis process should be at a comparable level.
Fig. 3 proves that the mixing of silver nanocolloid into
the alkaline natural rubber latex did not affect the stability
of SNP in the medium. Even after mixing the SNP with the
NR latex the maximum absorption at 429.1 nm did not
change. The control sample of natural rubber latex (Fig. 3
(a)) itself does not show any peak in the UV–Vis spectrophotometer
analysis. The characteristic absorption peak at
429.1 nm seen in the mixture of silver nanocolloid withnatural rubber latex (Fig. 3(b)) proves the occurrence of
silver nano particles in the latex used to produce NRLF with
SNP.