Browsing by Author "Saliu, O.D"

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    Composites based on poly (vinyl chloride) and organically modified clay.
    (Asian Journal of Chemistry. Asian Chemical Society, 2018) Azeh, Y; Elele, U.U.; Muhamad, A.M; Yohanna, B.P.; Fabiyi, O.A; Saliu, O.D; Muhammad, U.B; Ameh, O.A.E; Garba, B; Yusuf, B.M
    Composite based on native and chemically modified clay have been prepared via stir-solution intarcalation method in poly(vinyl chloride) method (PVC) matrix using dimethyl sulphoxide as a solvent and ethylene glycol as a plasticizer. The composite structures based on PVC-native clay (control) and PVC-organo clay were characterized using scanning electron microscopy and FT-IR spectroscopy. The results indicated that the modified clay particles were well intercalated and homogeneously dispersed in the PVC matrix. As a result, exfoliated PVC-organoclay composite were formed. The success of modification was revealed by FT-IR result as it confirmed the formation of CO, -COO- CH3 and -C-CH3. The formation of hydrogen bonds between the solvent molecules (dimethyl sulfoxide) and the inner surface hydroxyl groups of clay was evidenced by the appearance of hydrogen bonds. the elemental analysis of clay samples made by EDX indicated the presence of radon, a radioactive element in clay samples up to 52% of the total concentration of elements present in the clay sample. Biodegradation studies showed that microbes were able to biodegrade composites with high activity recorded at dump site. Absorption kinetics of composites showed that organoclay-PVC composites were resistant to water, acid and base solutions compared to control samples based on immersion time for the test. This study demonstrated that vinegar is useful for the chemical modification of clay for enhanced surface interaction with PVC and improvement of barrier properties.
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    Porous Starch Citrate Biopolymer for Controlled Release of Carbofuran in the Management of Root Knot Nematode Meloidogyne incognita
    (Biotechnology Reports. Elsevier, 2020) Fabiyi, O.A; Saliu, O.D; Claudius-Cole, A.O; Olaniyi, A.O; Oguntebi, O.V; Olatunji, G.A
    The undesirable environmental impacts of inappropriate application of pesticides have brought about research into new matrices for controlled release of pesticides. Porous starch citrate biopolymer was designed for the release of carbofuran in this experiment and characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Thermo-Gravimetric Analysis (TGA) for functional group, surface morphology and thermal stability properties respectively. The SEM revealed highly stabilized porous starch citrate biopolymers with porous structures and gradients suitable for controlled release studies. The transmittance bands at 3347, 1714 and 1073 cm 1 for OH, CO and COC ¼ stretching vibrations further confirms the successful synthesis of the biopolymer. TGA showed an increase in the thermal stability after citric acid modification with one-step decomposition from 290 C to 500 C. From Korsemeyer-Peppas model, the carbofuran-porous starch citrate (CBFN/PRS/ STH/CTRT) followed a lower diffusion release model with gradual increment in all the quantity of carbofuran loaded. An accelerated rate of diffusion percentage was seen in direct application of carbofuran. Egg hatch and mortality of juveniles were recorded on daily basis for seven days. Direct application of carbofuran (CBFN/DRT) and carbofuran-porous starch citrate biopolymer gave the best results with significant (p < 0.05) reduction in egg hatch and higher percentage mortality. The rate of release of carbofuran from the starch citrate bio polymer matrix was significantly lower than the direct application, and in spite of the slow rate of release, higher juvenile mortality and reduction in egg hatch was achieved