THE USE OF LOCALLY OBTAINED RUBBER LATEX AS BINDER IN PAINT FORMULATION
ABSTRACT
Considering the huge amount of money being spent on the importation of PVac (Poly vingl acetate) which is widely used as binder for paint manufacturing the efforts of this project cannot be over – emphasized. Going though this project, it will be agreed that a gaint stride has been made towards the reduction of foreign exchange being siphoned out of the country through the importation of Pavc for paint manufacturing.
The natural rubber later used for this purpose was collected from Ozozo forest Rubber plation in Delta State. This later will naturally coagulate within 4 – 2,4 house, if unpreserved, therefore the later used for this project was preserved with an anti – coagulant (Ammonia) to avoid coagulation. Experiments carried out on this later exposed some of its characteristics. Naturally a freshly tapped Rubber later will have a PH of between 6.8-7.0, but because of the ammonia used in the preservation the PH was found to be 10.97. Another property of the later which affect the pigment volume concentration (PVC) of paints coating is the dry rubber content or the total solid content which was found through experiment to be 42%.
The normal process of paint manufacturing was employed. Shere were two samples of paints produced each differing from the other by the weight of either PVAC or the rubber later used. One sample made of PVAC as a binder was regarded as standard and the other one with rubber later as binder compared with it.
In each case the binder was added last since it is known that it will not withstand the high shear stress developed in the machine during dispersion.
The PH of the various samples were 8.1 and 10.15 accordingly.
The second sample with rubber later as binder has a PH value outside the standard PH.
The paint produced can be compared with the standard favourably.
Difficulty encountered during the formulation include the inability of Natrosol to dissolve due to delay in pouring the dissolved natrosol in the water faskly and then pour into the other dispersed components. This however was poured off and new formulation made which game the desired result.
The binder power in PVA formulation is much better an concise with that of standard point and it has greater fitness.
