63 research outputs found
Low density polyethylene tapioca starch degradable biofilms with palm oil based processing aid for blown film extrusion
In this study, tapioca starch-based polyethylene biofilms with various starch contents, ranging from 5 to 40 wt%, were prepared with added plasticizers and polyethylene-grafted-maleic anhydride (PE-g-MA) as compatibilizer by a one-step process. The pellets of tapioca starch-based low density polyethylene (LDPE/TS) were first produced using a twin-screw extrusion process, followed by film blowing extrusion process to produce biofilm samples. Two types of plasticizers, commercial glycerol and palm oil based olein, were added to produce the best formulation for the film blowing process. Palm oil based olein influenced the processing of biocomposites by inducing lower viscosity, better dispersion and flowability. The biocomposites with addition of fixed amount of palm oil based olein displayed excellent film blowing ability compared to glycerol. Scanning electron micrograph of this biofilm with incorporation of starch up to 30 wt% showed good dispersion of starch granular in the polymer matrix. Adding compatibilizer increased the compatibility of the blends, and thus the mechanical properties of tapioca starchbased biofilms were improved. Optical properties, such as haze and gloss of biofilms, decreased as the starch contents increased, coinciding with the starch particle size in the polymer matrix. The barrier properties of tapioca starch-based biofilms, such as water uptake, moisture content and water vapour transmission rate were higher than pure LDPE, due to the hydrophilic characteristics of starch. Biofilms exposed to outdoor weathering, fungi, enzyme and controlled soil burial test demonstrated significant changes on weight loss and surface structure due to photodegradation by sunlight and microorganism activities. Biofilms with starch contents 10 to 40 wt% were determined safe to be used as food plastics packaging for aqueous, non-acidic and acidic foods, oils and processed dry food containing fat and alcoholic ingredients
Characterization of injection molded high density polyethylene/rice straw biocomposite
Polymer composite have been subjected to increasing interest, study, and utilization for some
decades. The increase in environmental concern rationalize the use of reduce polymeric
materials, not only due to their non-biodegradab
ility, but also due to their production requires
large amounts of oil as raw material which is notor
iously not renewable. All these issues induced
to look for alternatives. Thus, the interest aris
es toward polymer composites filled with natural
organic fillers. Composite materials (or composites for short) are engineered materials made
from two or more constituent materials with
significantly different physical or chemical
properties and which remain separa
te and distinct on a macroscopic level within the finished
structure. Composite materials made from plan
t fibers are receiving a great deal of today
attention since they are consider
ed an environmentally friendly recourse. Among all reinforcing
fibers, natural fibers have gained their importa
nce especially for load bearing applications.
Natural fiber reinforced polymer composites ar
e superior over synthe
tic fiber reinforced
composites in certain properties like enhanced
biodegradability, combustib
ility, lightweight, ease
of recyclability, etc.
These advantages place the na
tural fibers composites among high
performance composites having economical and
environmental advantages, with good physical
properties [1]
Biocomposites based on oil palm tree as packaging materials
Every parts of the oil palm tree can be utilized to form useful products, including the waste from palm oil processing either intermediates or final biomasses. Utilization oil palm wastes and palm oil product will be presented for the application in the packaging industry, especially as environmental friendly packaging materials. For the development of these new biodegradable packaging materials, product and waste from oil palm tree are compounded to form biocomposites. Empty fruit bunch, waste that is derived after palm oil extraction process, is grinded and compounded with polyethylene to form biocomposites for blow film process. Palm cooking oil (PCO) is used as processing aids/lubricant in the blown film processing of low density polyethylene with empty fruit bunch fiber (LDPE/EFB) to form biofilm. This oil ease the process ability of LDPE/EFB on the conventional blown film thermoplastic machinery. The higher the composition of the PCO the better will be the processability of LDPE/FFB as the resistance to flow is decreased. With PCO composition greater than 2% the processing parameters of LDPE can be used to process LDPE/PCO/EFB into film. Tensile properties of the biocomposite film are found to be dependent on the PCO composition and comparable to the polyethylene film at low PCO composition. As the composition of PCO in LDPE/EFB is increased the tensile strength and elongation at break of the biofilm is decreased
Analysis on physiochemical properties of cellulose fiber from rice straw waste
Green biobased polymeric membranes are being increasingly studied for different applications. In this study, freeze dried cellulose fiber with 35% yield was isolated from rice straw. The cellulose fiber was obtained through bleaching and delignification of the rice straw waste using soxhlet instrument and facile method of alkali treatment, respectively. The cellulose fiber was analysed through X-ray powder diffraction (XRD), fourier-transform infrared spectroscopy (FTIR), zeta potential analyzer and scanning electron microscope (SEM). Compared to the straw, all physicochemical properties of treated cellulose fiber increased with zeta potential up to-33.61 mV. FTIR revealed that the treatments on the straw was successful to obtain cellulose fiber with high purity. In addition, the morphological study illustrated cellulose fiber with organized structure
Silver nanoparticles loaded activated carbon synthesis using Clitorea Ternatea extract for crystal violet dye removal
Dyes are coloured compound which are widely used in textile, painting, rubber, cosmetics, plastics and leather industry to colour their products. However, the irresponsibility of certain manufacturer results in producing dye waste and channel it to water resources had become one of the biggest challenges in water pollution. In this study, an effective solid adsorbent derived from sustainable sources for adsorption capacity study was produced which is silver nanoparticles loaded activated carbon (Ag NPs-AC) to remove crystal violet (CV) dye. Adsorption process are cost-effective, simple and flexible with various dye pollutants. Silver nanoparticles (Ag NPs) was synthesized from Clitorea Ternatea flower extract that utilizes functions as stabilizing agents for silver nitrate (AgNO3) to promotes environmental friendly with no toxic chemicals produced and loaded in activated carbon (AC). Characterization of Ag NPs was analysed using UV-Visible which correspond to peak at 408 nm and XRD analysis. Four peaks values for silver at 2θ of 38.19°, 44.43°, 64.57°, 77.43° and average crystallite size of Ag NPs and Ag NPs-AC were calculated to be 16.11 nm and 36.13 nm respectively that were obtained from XRD pattern. The adsorption capacity of Ag NPs-AC was analysed and the optimum conditions were determined using different parameters which are the Ag NPs-AC ratio (1.0 g), contact time (240 min), adsorbent dosage (30 mg) and pH of CV dye (10). The highest percentage removal of CV dye using Ag NPs-AC was recorded up to 97% at 240 min with 30 mg dosage. Ag NPs-AC as adsorbent is a promising advanced materials in removing water pollutants with viable conditions and can applied in the wastewater treatment industry
GO-modified membranes for vanadium redox flow battery
Graphene oxide (GO) has attracted tremendous attention in membrane-based separation field as it can filter ions and molecules. Recently, GO-based materials have emerged as excellent modifiers for vanadium redox flow battery (VRFB) application. Its high mechanical and chemical stability, nearly frictionless surface, high flexibility, and low cost make GO-based materials as proper materials for the membranes in VRFB. In VRFB, a membrane acts as the key component to determine the performance. Therefore, employing low vanadium ion permeability with excellent stability membrane in vanadium electrolytes is important to ensure high battery performance. Herein, recent progress of GO-modified membranes for VRFB is briefly reviewed. This review begins with current membranes used for VRFB, followed by the challenges faced by the membranes. In addition, the transport mechanism of vanadium ion and the stability properties of GO-modified membranes are also discussed to enlighten the role of GO in the modified membranes
Synthesis and properties of Chitosan nanoparticles cross-linked with tripolyphosphate
Chitosan nanoparticles (ChNPs) have been extensively examined for various biomedical applications due to their advantages include large surface area, biodegradability, and biocompatibility. The purpose of this research was to synthesize ChNPs using a simple ionic gelation technique by the interaction of low molecular weight chitosan (LMWC) and sodium tripolyphosphate (TPP) as a cross-linking agent. ChNPs, TPP, and LMWC were analysed by X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra that indicated the formation of ChNPs, attributing to the rearrangement of the nanoparticles after adding the TPP cross-linker into the LMWC solution. XRD analysis exhibited that ChNPs were amorphous, due to the effect of TPP cross-linker. Dynamic light scattering showed the nano-dimension of ChNPs with a hydrodynamic size of 68.50 nm. Thus, the obtained results indicated that the properties of chitosan were improved through converting it into nanoparticles using TPP initiated ionic gelation procedure
Green synthesis of silver nanoparticles using Hibiscus sabdariffa leaves extract
The present paper reports the synthesis of silver nanoparticles (Ag-NPs) by a green method using Hibiscus sabdariffa (H. sabdariffa) leaves extract as reductant and stabilizer. The synthesized Ag-NPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). UV-vis spectrum of synthesized Ag-NPs showed a peak at 378 nm. TEM analysis revealed that the particles were spherical and irregular in shape and has average size around 56.52 nm. This structure and size of particles were confirmed by AFM analysis. The UV-vis and FTIR spectrum provides evidence of the presence of caffeic acid component as a representative biomolecule in stabilising the nanoparticles based on previous studies. Hence, this study advocates that H. sabdariffa have potential for synthesizing nanoparticles
Copper/graphene based materials nanocomposites and their antibacterial study: a mini review
Due to their biocidal activity properties, graphene based materials have been widely studied especially in biomedical, agriculture and water treatment process which focus on mitigating the microbial resistance problem. However, the antibacterial performance of these materials alone are relatively weak and need to be improved in order to enhance their biological activity. Copper nanoparticles is a low cost metal also has the antibacterial properties which is almost similar with the silver and gold nanoparticles. The combination of these two materials had produced to a new potential material as another alternative for the antibacterial agents. Therefore, in this work, a brief review of copper/graphene based material nanocomposites and their antibacterial study was discussed
Fabrication of hydrophilic silica coating varnish on pineapple peel fiber based biocomposite
In the last several years, the interest on hydrophobic and hydrophilic solid subtract was increased due to many applications in daily life, agriculture and industry. The continuous effort has been made to fabricate suitable material with more efficient fabrication method. In this research, physical blending method have been used by mixing four components of modifying agent with organic beeswax varnish at different weight percentage. Those modifying agents consists of decamethylcyclopentasiloxane (D5), Silica nanoparticles (R812S), Polydimethylsiloxane (BP-9400) and non-ionic surfactant (Triton X-100) were mixed in the mass ratio of 52:3:34:1. The modified varnish produced was coated on Pineapple peel fiber (PAPF) biocomposite and were characterized using Water Contact Angle (WCA) instrument, Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). Based on the wettability index analysis; the value of water contact angle was reduced when increasing weight percent of modifying agents from 101.87 to 22.98°. The morphology of the surface was observed to have more silica nanoparticles, along with the increasing concentration of modifying agent. It also supported by FTIR which shows the presence of Si-O peak at 1030.88 cm-1. These results proved that the modifying agent and organic beeswax varnish had successfully produced hydrophilic coated on the PAPF surface
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