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Nanocellulose is a promising nanomaterial that can be used in various applications such as reinforcements for composite films. Agricultural lignocellulosic wastes, such as coconut husks, offer great advantages as raw materials for nanocellulose extraction due to their abundance and economic viability. The aim of this study is to extract nanocellulose from matured coconut husk. Nanocellulose was extracted using sulfuric acid hydrolysis and characterized using Atomic Force Microscopy (AFM). Results showed that nanocellulose extracted from matured coconut husk has 2.26% yield with agglomerated, rod-shaped structures. An average aspect ratio of 3.16 ± 1.82 nm was also obtained.

Materials made from renewable resources offer a promising strategy for reducing environmental problems. Starch is a well-known alternative among several biodegradable materials due to its availability, cheap cost, and degradability. This research aims to develop a degradable film from cassava starch and use citric acid as the crosslinker. Light transmittance measurement reveals that the films produced have high UV barrier capacity in the UV region and above 80% transmittance values in the visible region. Additionally, it was found that the film with 10% citric acid had a favorable balance of tensile strength, elongation, and fracture stress.

Kapok fiber has been known for its hydrophobic-oleophilic characteristics and exhibits a great potential as oil sorbent. Methods in enhancing its hydrophobicity have been explored to improve its sorption performance in oil-in-water applications. This study investigates the oil sorption performance and hydrophobicity of kapok fibers coated with calcium stearate, a known waterproofing agent. The calcium stearate solution was prepared by mixing known amounts of stearic acid and calcium chloride in an ethanol solution. This was followed by hydrolysis using 0.12 M sodium hydroxide solution. The calcium stearate-coated kapok fibers exhibited higher hydrophobicity compared to raw kapok fibers with a water contact angle of ~137°. It achieved the highest oil sorption capacity and reusability of 50 g/g and 65% for viscous motor oil, respectively.

Kapok fibers were used as a filtering medium in a column-type filtration set-up to separate diesel from water molecules in dynamic conditions. The amount of diesel flowing out the filtration system with respect to time was monitored. The times wherein the diesel first came out the filtering system (breakthrough time) were shorter at higher influent concentration and faster flow rate. Meanwhile, the total sorbed diesel molecules in the filtering system were increasing with the influent concentration while invariant with flow rate. The shorter breakthrough time was associated with the higher amount of diesel molecules that could be sorbed at a shorter time and the rate at which the overall processes of sorption-desorption-resorption proceeded. On the other hand, the sorption capacity of the system was viewed to be affected by the amount of moving diesel molecules that would interact with the kapok fibers and/or surface-sorbed diesel molecules but not by the contact time.

Shelf life in ground and tree nuts are often assessed based on aesthetic appearance, nut integrity, color and most importantly, taste and edibleness. Nuts with considerable level of rancidity and free fatty acids due to degradation of oils indicate expiration or decay. We prepared a shellac-lemongrass oil blend coating using food-grade ingredients and assessed its potential to extend shelf life of Pili nut (Canarium ovatum) kernels. A glossy, hard but considerably brittle coating for the pili kernels were prepared with varying numbers of layers. On average, the mass of coating added per dip is 0.10 g, and the thickness of 5-layers of coating is 0.3 mm. The obtained reflectance spectra of the coated pili kernels implied the translucent nature of the coating, but becomes opaque as the number of layers are increased. Peroxide value (PV) and free fatty acid value (FFAV), were also measured at 10 days after application of coating. PV was lowest in the nuts with 5 coating layers, while this treatment did not reduce FFAV. These results indicate the effectiveness of our coatings in preventing peroxide production probably by blocking oxygen penetration and ultraviolet exposure, which are important triggers production of peroxide and other free radicals. Further tests and time-series experiments are planned to assess the dynamics of peroxide levels and the overall potential of our coating technology for Pili nut.

Stable electronic configuration between the interface of an n-type oxide semiconductor core and a p-type polymer shell is necessary in order to guarantee a consistent functioning core-shell structure. This research aims to use silane-aniline to link between an n-type Titanium (IV) oxide (TiO2) core and p-type polyaniline emeraldine salt (PANI-ES) shell. Core-shell structure was created by functionalizing TiO2 powders with silane aniline molecules using simple soaking technique and then polymerizing the attached aniline molecules using an oxidative technique. Infrared spectroscopy reveals the presence of Si-O bonds signifying the presence of linkage between the inorganic core and polymeric shell. Polymerization of the attached aniline molecules may have led to coupling of aromatic rings to form long polymeric structures which caused widening and shifting of aromatic rings’ IR peak to lower wavenumber. In conclusion, silane-aniline was successfully utilized to connect the n-type TiO2 core and p-type PANI-ES shell.

Polyaniline-zinc oxide composite on Kapok paper were fabricated for methylene blue dye removal in aqueous solution. Kapok fibers were fabricated into papers. The fabricate paper served as substrate for the zinc oxide-polyaniline composite. Zinc oxide particles were deposited on the Kapok paper using an in-situ method while polyaniline molecules are deposited on paper using Successive Ionic Layer Adsorption and Reaction (SILAR) method. The polyaniline molecules were deprotonated using sodium hydroxide (NaOH) to be able adsorb cationic dyes in aqueous solution. The samples were characterized using scanning electron microscope (SEM), energy dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Results show that the deprotonated polyaniline nanocomposite was able to remove at about 75% more dye compared to the as-synthesized polyaniline nanocomposite.

This study dealt with the synthesis and characterization of thin transparent conducting films (TCF) from cellulose acetate (CA) blend and polyaniline (PANI). CA was produced from the pulp of abaca hybrid 7. CA-PANI films with different PANI loadings (0, 0.125, 0.25, 0.50, 1.0 and 2.0%) were produced using solvent casting method. Chemical transformations were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. The conductivity was measured using the Four-Point Probe Test. Morphological characterization was done using Scanning Electron Microscopy (SEM). The transparency of the films was determined using UV-Vis Spectroscopy. FTIR spectra proved the embedment of PANI in the CA matrix. It was found that increasing the PANI loading increases the conductivity of the films but up to a certain limit. The highest average conductivity at 2.0264 x 10-5 S/m was observed in CA-PANI films with 0.50% PANI loading. SEM images revealed that conductivity is a function of PANI loading by forming networks. Further addition of PANI (1.0 and 2.0%) resulted to decreased conductivity due to agglomeration. Transparency, on the other hand, is negatively affected by PANI loading.

In this study, conducting polyaniline (PANI) Emeraldine salt molecules were coated on polyethylene (PE) board using successive ionic layer adsorption and reaction (SILAR) technique. The number of dipping cycles were varied and the surface conductivity of the samples were measured using four-point probe technique. Fourier Transform Infrared (FTIR) spectroscopy was also done to verify the identities of the coated samples. Results show that PANI Emeraldine salt was successfully coated on PE board as indicated by the peaks of FTIR spectra. Surface conductivity of the PANI Emeraldine salt coated PE board increases with increased number of dipping cycles due to increases interconnectivity of PANI molecules. The conductivity decreases after reaching an optimum point at 80 dipping cycles due to either hindrance of movement of charges or the breaking away of chunks of PANI molecules. These results opens up several applications such as memory devices and erasable circuit boards.

Nanostructured zinc oxide (ZnO) particles were grown on paper substrate made from Abaca hybrid 7 pulp. Microwave irradiation technique was used at power levels (180 and 540W) and exposure times (5, 10, 20 and 25 minutes). Chemical transformations were observed using Fourier Transform Infrared (FTIR) Spectroscopy. The effects of the power levels and exposure times on the morphology of the nanostructures were determined using scanning electron microscopy. FTIR spectra proved the embedment of ZnO on the paper substrate. Power levels and exposure times affected the distribution, particle size and structure of the ZnO nanoparticles. Higher power level and longer exposure resulted to the formation of more ZnO with larger particles. Grainlike and flowerlike ZnO nanostructures were formed at lower and higher levels, respectively.

In this study, polyaniline on silane-functionalized zinc oxide was fabricated. The zinc oxide particles were functionalized by soaking in silane aniline-ethanol solution. Afterwhich, the polyaniline was polymerized on the grafted silane aniline molecules using oxidative polymerization. The FTIR spectra showed vibrational peaks associated with the silane aniline molecules and grafted polyaniline. The sampled soaked in silane aniline coupling agent showed FTIR peaks associated with grafted silane aniline. The sample soaked for one minute showed FTIR peaks associated with ortho-coupled aniline units that is formed during the start of aniline polymerization. The sample soaked for three minutes showed FTIR peaks that is broader compared to others due to ring vibration in long polymeric chain.

Cotton fabric was coated with polyaniline molecules using Successive Ionic Layer Adsorption and Reaction (SILAR) technique. This method provides layer by layer deposition of polyaniline molecules. Infrared spectrum showed the vibrational peaks attributed with the presence of polyaniline molecules on the samples. Four-point probe measurements were done to obtain the surface conductivity of the samples. Upon increasing the dipping cycles, the conductivity of cotton fabric significantly increases. The optimum number of dipping cycle is found to be at 130. Beyond the optimum dipping cycle, the conductivity starts to decrease.

Polyaniline emeraldine salt (PAni-ES) was successfully deposited on paper through layer-by-layer technique. In this method, a paper was alternately dipped in aniline monomer and an oxidizing agent for different dipping cycles. This process produced green PAni-ES on paper. The morphology of the samples showed polymeric networks with pores, fiber-like structures and aggregates. There is a transition from frequency-independent to frequency-dependent conductivities of the samples. The conductivity increased with increasing number of dipping cycles. The frequency-dependent conductivities follow the power-law behavior reflecting conducting network and hopping mechanisms. Lastly, the conductivities with frequency followed a scaling behavior reflecting a common physical mechanism in PAni-ES on paper.

CuSO4-deposited and CuO-deposited polyurethane foam (PUF) were fabricated in this study. Image analysis showed color transformation of the PUF from yellow to blue-green, which is indicative of the deposited CuSO4 particles on the substrate. Further color transformation of the material from blue-green to greenish-brown after soaking in NaOH suggest that the CuSO4 oxidized to form CuO, which was confirmed by the presence of CuO peaks during XRD analysis. SEM images also reveal the presence of CuO rods embedded in the PUF. The antibacterial activities of the CuSO4- and CuO-deposited samples against the gram-negative Escherichia coli bacteria were conducted.

In this study, acid-doped polyaniline-zinc oxide composites were prepared and used to investigate their effect on the removal of methyl orange dye under visible light exposure. The composites were prepared by mixing different volume fractions of polyaniline and ZnO powders. Their effect on the removal of methyl orange was determined through transmittance spectroscopy. Polyaniline-zinc oxide composites of 75% volume fractions showed the highest percent removal of methyl orange. This was attributed to the presence of p-n heterojunctions and adsorption capability of the polyaniline molecules.

Polymer-oxide semiconductor exhibits a promising application on electronic devices. In this study, zinc oxide-polyaniline (ZnO-PAni) junctions were constructed which showed a photodiode-like behavior. The junctions were built through connecting the electrodeposited zinc oxide to electrodeposited HCl-doped polyaniline. Without illumination, the junctions exemplify a diode-like behavior (e.g., large amount current at forward-bias while small amount of current at reverse-bias). When illuminated, the junctions exhibit a photodiode-like behavior. In such, the reverse-bias current increases with light intensity.

Hydrophobic surfaces are eyed for their self-cleaning ability because water droplets can roll on them (instead of clinging), thus the surface have capability to remove dirt. Hydrophobic surfaces were created by coating functionalized Titanium Dioxide-based paint. The paint was fabricated by reacting fluorosilane molecules in ethanol with titanium dioxide nanoparticles. Ethanol also serves as the volatile suspension medium that evaporates when the paint is coated on surfaces. The paint was coated on different surfaces by simple dipping. Contact angle of coated aluminum sheet, soda-lime glass, filter paper and silicon carbide polishing paper showed hydrophobicity. Water droplets are made to roll on coated soda-lime glass at angle of 0.057°. The ability of water droplets to roll highlights the coated surface self-cleaning potential.

Many traditional photocatalytic materials such as ZnO and TiO2 are ultraviolet light-triggered due to their wide band gap, however indoor light and sunlight reaching the surface of the earth are in the visible light region. This research aims to fabricate a photocatalytic material that can be triggered using visible light. Ceramic composites with ZnO and CuO interfaces were constructed using heterogeneous mixing technique. The photocatalytic activities of the samples were determined through their ability to degrade methyl orange dye under visible light illumination. Results show that the existence of the ZnO-CuO interface improved the visible light photocatalytic activity of the material.

High voltage electrodeposition technique was successfully employed in coating a low conductive glass. The technique involved the use of constant input voltage (e.g., 2000V) to coat the soda-lime glass electrode. Dissolved copper sulfate pentahydrate in sulfuric acid-water solution served as the electrolyte in the deposition process. The surface conductivity of the electrodeposited coated glass improved compared to that of the uncoated glass. The surface conductivity increased as high as 735% at 30 minutes deposition time using 2000 V input voltage. However, the transmittance decreased with surface conductivity. This indicated that the conductive particles that adhered on the surface were blocking the passage of light. Furthermore, the AFM image shows that the adhered particles were deposited besides the scratched region. This observation supports the need to roughen the glass surface before employing the high voltage electrodeposition technique.

Synthesis of Zn-doped PbTiO3 was done using solid-state method. The effects of varying amount of Zn were investigated. Stoichiometric amount of precursors were mixed and ground. The pressed mixtures were calcined at 800°C and sintered at 1,100 °C after regrinding. The samples were characterized using X-ray Diffraction (XRD), Differential Thermal Analysis (DTA), and Scanning Electron Microscopy (SEM). The XRD verifies the existence of PTO in the samples. DTA shows the thermal profile of the samples. Among the different concentrations of Zn that were added, the sample with 5% mole fraction showed the lowest melting point. For 5% mole fraction and greater, SEM images showed flattening and fusing of grains.