Quality improvement of long oil alkyd (LOA) resin requirements in the formulation of Hi-gloss paints

This research aimed at lowering the non-volatile matter (NVM) of long oil alkyd (LOA) resin to meet the resin requirements in producing Hi-gloss paints. The research also aimed to assist Hi-gloss paint manufacturers who require solid resin content below 70%.

The research utilised both the document review and experimental methods. The experimental method, which involved the blending process, was used in lowering the NVM of LOA resin, whereby eight experiments were conducted as reputations to obtain accurate data and results. A factorial design was used in the design of the experiment (DOE), where three factors were required to be evaluated: specific gravity, viscosity and NVM and two levels were required: weight of LOA and white spirit.

The NVM of LOA resin was successfully lowered, and different shades of paint were produced for reliability testing. The quality parameters of Hi-gloss paints that used the modified LOA were all found within the company's specifications compared to those with unmodified LOA, where some parameters were either above or below the specifications. However, all samples with the NVM of LOA used below 50% were found to be poor in terms of quality during the reliability testing. So, if the company had used the modified LOA resin in the production of Hi-gloss paints, it would have potentially saved 18,925.2 kg and 9,446.4 kg, respectively, of LOA just in producing Hi-gloss black and white paints only. Moreover, the cost of 1 kg of LOA is $2.3, which is equal to Tanzanian Shillings (Tshs) 5,290. The company would have potentially saved Tshs 100.114 million Tshs and Tshs 49.97 million Tshs in producing Hi-gloss black and white paints, respectively, making a total of Tshs 150.08 million per year. This was counted as a loss during that year because they did not use LOA resin with 50% NVM in production.

This study focused on LOA resin used in producing Hi-gloss paints. The study also did not consider other categories of alkyd resins used in producing paints and varnishes e.g. epoxy resin and short and medium oil alkyd resins.

This is probably the first alkyd resin improvement study conducted using white spirit as Tanzania's main agent or material. The study utilised vegetable oils such as coconut, sunflower and tobacco seeds.