Effect of Particle Sized Clay Extender Pigment on Alkyd Paint Formulations

The effects of particle sizes on the properties of Ihitte-Uboma clay formulated alkyd paints have been studied. The clay particle sizes studied are 75, 150and 300 µm at clay contents 0 – 80 wt. %. Xylene was used as the solvent while TiO2 formulated alkyd paint served as reference alkyd paint in this study. The extender pigments were characterized using X-ray fluorescence and scanning electron microscope. The physic-chemical properties of the extender pigments were determined using ASTM measurements. The properties of the paint samples were evaluated according to ASTM. Results showed that the alkyd paints had higher viscosities which increased with increases in clay contents at the three clay particle sizes investigated. The drying properties of the paints were generally good. The dry film thicknesses of the formulated paints were in the range of 0.29 – 0.38 mm. The formulated paints exhibited moderate settling tendencies at the 75 µm clay particle size when compared with the other particles. There was no mildew formation observed on all the paint samples on exposure to rain and sunlight. Generally, all the paint samples exhibited good resistance to distilled water, 3 % H2SO4, and 3 % Na2CO3. The formulated paint samples were affected on 3 % NH3 immersion which resulted to wrinkles. The improved properties obtained from the clay formulated paints which include thermal and colour stability, viscosity, specific gravity

Uptake of Automobile Fluids by Dynamically Vulcanized Recycled Polyethylene/natural Rubber (rPE/NR) Biocomposites

Abstract This study presents long term sorption properties of automobile fluids -premium motor spirit (PMS) and automotive gas oil (AGO) in dynamically vulcanized recycled polyethylene/natural rubber (rPE/NR) thermoplastic elastomer biocomposites. The effect of oil palm empty fruit bunch (OPEFB) filler and maleic anhydride graft polyethylene (MAPE) as compartibilizer on the rPE/NR blends were also studied. The automobile fluids uptake trend was observed to reducewith OPEFB incorporation. Uptake of the automobile fluids by the biocompositesincreased rapidlywithin the first 24 hours and subsequently increased gradually within the 7 days period studied.The analysed results also showed that both the uncompartibilized and compartibilized thermoplastic elastomer biocomposites absorbed more PMS than AGO at same OPEFB loading and immersion time. Diffusion, sorption, and permeation coefficients of both PMS and AGO for the compatibilizedbiocompositesdecreased with increasing OPEFB content. The mode of transport of the automobile fluids into the filled rPE/NR blends has been found to be Fickianwhere the n values ranges from 0.1 to 0.4 for the various systems. This study also revealed greater degree of interaction between the PMS and the biocomposites than the AGO and the biocomposites

Effect of Particle Sized Clay Extender Pigment on Alkyd Paint Formulations

The effects of particle sizes on the properties of Ihitte-Uboma clay formulated alkyd paints have been studied. The clay particle sizes studied are 75, 150and 300 µm at clay contents 0 – 80 wt. %. Xylene was used as the solvent while TiO2 formulated alkyd paint served as reference alkyd paint in this study. The extender pigments were characterized using X-ray fluorescence and scanning electron microscope. The physic-chemical properties of the extender pigments were determined using ASTM measurements. The properties of the paint samples were evaluated according to ASTM. Results showed that the alkyd paints had higher viscosities which increased with increases in clay contents at the three clay particle sizes investigated. The drying properties of the paints were generally good. The dry film thicknesses of the formulated paints were in the range of 0.29 – 0.38 mm. The formulated paints exhibited moderate settling tendencies at the 75 µm clay particle size when compared with the other particles. There was no mildew formation observed on all the paint samples on exposure to rain and sunlight. Generally, all the paint samples exhibited good resistance to distilled water, 3 % H2SO4, and 3 % Na2CO3. The formulated paint samples were affected on 3 % NH3 immersion which resulted to wrinkles. The improved properties obtained from the clay formulated paints which include thermal and colour stability, viscosity, specific gravity

Effects of Mycobacterium Tuberculosis Macrophage Interaction: Surface Energetic Mechanism

The mechanisms effects of mtb  macrophage using surface energetic in determining the interaction processes with the surface interfacial energies explained using van der Waals concept of particle  particle interactions. The Lifshitz derivations for van der Waals forces were applied as an alternative to the contact angle approach which has been widely used in other biological systems. The methodology involved taking sputum samples from twenty infected persons and from twenty uninfected persons for absorbance measurement using a digital Ultraviolet visible Spectrophotometer. Matlab software tools were used in the mathematical analysis of the data generated from the absorbance values. The values of A132abs = 0.21631x10-21Joule (for mtb infected sputum) and Ã132abs = 0.18825x10-21Joule (for mtb/HIV infected sputum) were obtained. The free energies of adhesion calculated were found to be negative with combined Hamaker coefficient positive. The implication of this result is the positive value of the absolute combined Hamaker coefficient which entails net positive van der waals forces demonstrating an attraction between mtb and the macrophage. This however, implies that infection is very likely to occur. It was also shown that in the presence of HIV, the interaction energy is reduced by 13% confirming adverse effects observed in HIV patients suffering from tb. Negative Hamaker coefficient (-0.22669x10-19mJ/m2) indicated that separation of mtb is practical. The condition was sought for repulsion to occur and that condition was based on the value of A33 that would render the absolute combined Hamaker coefficient A131abs negative. Mathematically it was derived as A330.9527x10-21Joule which satisfies this condition for negative A132abs. To achieve the condition of A33 above, possible additive(s) in form of drugs to the sputum should be required