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As a large producer of pineapples, Indonesia also produces much pineapple peel waste. An effort to reduce this waste is to utilize it as a culture medium to produce bacterial cellulose (BC) pellicle. BC has properties of high mechanical strength, crystallinity, hydrophilicity, and high purity. This study produces a new biocomposite using BC pellicle with adding polyethylene glycol (PEG). This study aims to observe the effect of adding PEG4000 on BC/PEG biocomposite membrane structure. BC pellicle was produced using pineapple peel extract as medium fermentation and Acetobacter xylinum as a fermentation agent. After the fermentation process, produced pellicle was immersed in PEG 4000 at different concentrations (1, 2.5, and 5%wt). After that, the BC was dried using the freeze-drying method. The biocomposite BC/PEG4000 membrane was observed by X-ray Diffraction (XRD). The XRD result showed the BC membrane has diffractogram peaks found at 28 of 14, 16, and 22°. The addition of PEG4000 causes diffractogram new peaks at 28 of 19°. The higher addition of PEG4000 produces higher peak intensity. [ABSTRACT FROM AUTHOR]

Bacterial cellulose has many advantages when applied in various fields, such as medic. This research reported the fibrillation process effect on bacterial cellulose using a blender and HPH on bacterial cellulose produced from pineapple skin waste. The produced pellicle after the fermentation process was cleaned and received treatment from a blender and a High-Pressure Homogenization (HPH) machine. After that, the bacterial cellulose was dried using a freeze-drying method. Use scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) to observe bacterial cellulose. The SEM results showed that the HPH treatment created a more homogenous porosity in the bacterial cellulose. The XRD result presented that similar crystal positions were found at 14°, 16°, and 22°. The HPH treatment produced a higher crystallinity value. The FTIR test showed that the fibrillation process did not change the bonds of bacterial cellulose. [ABSTRACT FROM AUTHOR]

Chemical treatment is a standard method to improve natural fiber properties. Treatment using a chemical agent like Silane as Coupling Agent and CTAB (Cetyl Trimethyl Ammonium Bromide) as a surfactant can improve the natural fiber properties. The current study aims to observe the fiber surface morphology and obtain the mechanical properties of Sansevieria cylindrica fiber after being treated with a silane coupling agent and surfactant CTAB. The research was conducted by chemical treatment using Silane 5.0% and CTAB 5.0% on S.cylindrica fiber extracted from about a year and lengths up to 110 cm. The tensile test was performed using a single fiber tensile test, and the surface morphology was observed under Scanning Electron Microscopy (SEM). The results indicate that adding 5.0% silane coupling agent results in fiber strength of 281.5 MPa, elongation of 8.92%, and elastic modulus of 3.37 GPa. The addition of CTAB of 5.0% results in fiber strength of 237.4 MPa, elongation of 8.92%, and elastic modulus of 3.37 GPa. Increasing these properties has resulted from the bonding forming of silanols with hydroxyl groups of fiber. The morphology of the fiber surface shows a rough surface caused by removing impurities over the surface for the treatment of both coupling agents and CTAB. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles have properties as light absorbers to be used as light catalysts or solar cells. This study aimed to determine the effect of adding TiO2 nanoparticles to the structure and morphology of bacterial cellulose-based membranes produced from pineapple peel waste. The research was conducted by producing pellicles from pineapple peel extract. The pellicle was then disintegrated in 6 cycles using a high-pressure homogenizer at 150 bar. TiO2 variations were 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%wt. They were sonicated and dried in an oven for 8 hours at 60°C. The structure was analyzed using XRD, and SEM observed morphology. The results showed that in the BC membrane with additional TiO2, a new peak occurred on the diffractogram at 2θ=25.05°. It indicated the presence of TiO2 nanoparticles in the membrane. The diffraction peak occurred at 22.49° indicating that the cellulose belonged to Iβ cellulose. Additional 0% to 1% of TiO2 increased the membrane crystallinity index from 81.35% to 81.52%. The membrane crystallinity index decreased after an additional 1% TiO2, valuing 81.52% to 80.16% in the 2.5% sample. The membrane surface morphology showed that the TiO2 nanoparticles were still agglomerated and not evenly distributed on the BC membrane. [ABSTRACT FROM AUTHOR]

Polylactic Acid (PLA) is a popular material for 3D printing. PLA has the advantage of being biodegradable and derived from renewable resources. This study aims to determine the characteristic of recycled PLA extruded at various screw speeds. The extrusion process used a twin-screw extruder with screw speed as an independent variable consisting of 4 different screw speeds: 50 rpm, 60 rpm, 70 rpm, and 80 rpm, while the pulling speed and temperature of extrusion as control variables. The dependent variables are cross-sectional area, tensile strength and modulus elasticity obtained from tensile tests, fracture morphology observed using SEM, and structure observed using XRD. Results show the average cross-sectional area of filament increases along with higher screw speed. The overall tensile strength graph shows an increase in the average tensile strength of filament as screw speed increases, except for a speed of 70 rpm, where there is a decrease. The elastic modulus graph shows an unstable increase caused by flow instability. The fracture morphology of the filament gets rougher and more fibrous as the screw speed increases. XRD analysis shows that recycled PLA filament indicates peaks at 2θ=18° to 20.5° in 4 variables and that different screw speeds do not change the crystal structure of PLA. [ABSTRACT FROM AUTHOR]

Polylactic acid is an aliphatic polyester used as an environmentally friendly packaging application. The advantages of PLA are that it is easy to decompose and renewable and is made from renewable natural resources. Therefore, the material is extruded at different barrel temperatures to determine the effect of increasing the barrel temperature. This study aims to determine the changes in the mechanical properties, morphology, and structure of the polylactic acid filament by extrusion process with different barrel temperatures in the heating zone. Recycling is done in the third extrusion with different barrel temperature zone variations. Investigation of mechanical properties was determined by static tensile test, fracture morphology analysis of tensile test using SEM. The tensile test results show a gradual increase in tensile strength at each increase in the barrel temperature zone, from 60.48 MPa to an increase of 66.71 MPa, but at high barrel temperatures, the tensile strength decreases to 60.74 MPa. Morphological analysis of the tensile test fracture samples showed morphological changes, where morphological defects in the form of fibrous, voids, and scaly appeared after increasing the barrel temperature. Therefore, the barrel temperature parameter is not recommended to exceed 200℃ during the extrusion process. [ABSTRACT FROM AUTHOR]

Osmosis membranes have been widely used in industries for water purification, wastewater treatment, and biomedical applications. However, the current membranes still have some drawbacks, such as water flow resistance and vulnerability to fouling. Therefore, the development of more efficient and durable osmosis membranes is highly necessary. In this research, the researchers used bacterial nanocellulose extracted from Sargassum sp. as a material for producing more efficient osmosis membranes. The methods used in this study were experiments with two treatments: (1) control, and (2) Bacterial cellulose with a concentration of 1.0 wt% CuO nanoparticles. The nanocellulose was produced using a high-pressure homogenizer, followed by the synthesis of acetate nanocellulose and characterization of the nanocomposite membrane functionalized with CuO nanoparticles. The membranes were characterized using FTIR and XRD analysis. Bacterial cellulose from seaweed was successfully formed with a thickness of 1-3 cm. The results of the characterization analysis showed that the formed bacterial cellulose belonged to Cellulose type I with a crystalline degree ranging from 88.7% to 85.7%. The dry osmosis membranes were analyzed based on their functional groups using FTIR. The analysis revealed changes in transmittance at the peaks of O-H at wavenumbers 3122-3414 and Cu-O at wavenumber 424-673, resulting from the addition of CuO nanoparticles and causing changes in the value of the O-H bond in bacterial cellulose. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a natural polymer produced from microorganisms with characteristics, such as a fibrous with porous structure, impressive mechanical properties, and high purity. The synthesis of BC nanocomposites reinforced by ZnO nanoparticles has been applied to increase their properties. The study aims to identify the structure of BC nanocomposites after being reinforced by ZnO nanoparticles. The methods included BC synthesis using pineapple peel extract in static fermentation for 10 days, the alkalization procedure, and defibrillation of Bacterial Nanocellulose (BNC) by high-pressure homogenizer. ZnO was added as a reinforcement with concentrations of 2.5%, 5.0%, and 7.5%, sonicated and dried in an oven at 60oC for 20 hours. BNC/ZnO nanocomposite was characterized using X-ray diffraction. This work shows that membrane BC has peaks at 18°, 22°, and 26°. After the addition of ZnO, the dominant peak is obtained at a diffraction angle of 14°, 16°, 22°, and 26°, and the amount of peak is increased. The addition of ZnO does not affect the crystal size of the membrane, but it affects the crystalization of BC, which is the addition of 7.5% ZnO maximizes crystallinity until 87.45%. In the future, this membrane will be developed as membrane filtration for wastewater treatment. [ABSTRACT FROM AUTHOR]

Styrene is a plastic-type that is used as a heat-insulating material for buildings with properties difficult to be degraded, so that, this plastic should be reduced in utilization with an alternative biofoam. This study aims to present the influence of ZnO reinforcement on morphology and strength of cassava starch-based biofoam. The experiment started with biofoam synthesis using baking methods method. Biofoam made of cassava starch containing the ZnO of 0%, 3%, 6%, 9%. The resulting biofoam was observed using a scanning electron microscope and tensile test. The result indicates that the morphology of biofoam without the addition of ZnO had cavities with thick inter-cavity walls, while biofoam with variations of the addition of 3%, 6%, and 9% ZnO formed relatively the same cavities with thinner inter-cavity walls when compared to biofoam without ZnO addition. The highest strength value occurred in biofoam with the addition of 6% ZnO resulting in an average tensile strength of 0.9283 MPa. Nonetheless, when the ZnO content exceeded 6%, as demonstrated by the addition of 9% ZnO, the tensile strength of the biofoam declined to 0.7544 MPa. [ABSTRACT FROM AUTHOR]

The composite strength depends on the effectivity of interface interaction between the fiber and the matrix. The chemical treatment makes fiber surfaces more compatible with a hydrophobic polymer. So, this study aims to determine the influence of silane coupling agent concentration on the interfacial shear strength in the fiber composite of the Sansevieria cylindrica fiber. The methods included fibers treatment using ethanol as a dissolving and silane coupling agent with concentrations of 2.5%, 5%, 7.5%, and 10%. Fibers were embedded into the epoxy polymer for as long as 200 µm. The interfacial shear strength test was conducted through a single fiber pull-out test. Fiber morphology, crystallinity, and the functional group were observed using a scanning electron microscope and X-ray diffraction (XRD), respectively. As a result, the morphology of S. cylindrica fibers became rougher and showed a rougher surface after a silane concentration of 7.5%, but with the proper concentration, some fiber surfaces provided a good interface. Analysis using X-ray diffraction (XRD) on S. cylindrica fibers without treatment showed a crystalline index of 66%. Increasing silane concentration by 10% and the crystalline index by 75%. The treatment with a silane concentration of 0.0%, 2.5%, 5.0%, 7.5%, and 10.0% results in interfacial shear strength of 39.936, 59.300, 76.742, 83.965, and 91.321 MPa, respectively. The interfacial shear strength increases when the concentration of silane coupling agent increases, with the highest shear strength of 91.321 MPa at a silane concentration of 10%. The silane coupling agent changes hydroxyl groups into silanol groups in fibers, making a bond between the matrix and fibers. It can conclude that the treatment of a silane coupling agent increases the interfacial shear strength of the interface of S. cylindrica fiber-epoxy composite. [ABSTRACT FROM AUTHOR]

Cellulose produced from bacteria is a biopolymer that having high strength, purity and permeability so that it can be applied in various fields. The study aims to observe the morphology and structure of BC after being treated by a chemical reagent. The study was conducted using a BC pellicle that was produced from an extract of pineapple peel waste after being fermented for 10 days by Acetobacter xylinum. BC pellicle was treated by a chemical reagent solution (BmimCl, H2O2, and NaOH) by a concentration of 5%. BC pellicle was immersed in chemical reagent at 80 °C for 2 hours then dried in an oven for 6 hours at 70°C. The morphology observation was conducted under the Scanning Electron Microscope, and the structure was analysed using XRD apparatus. The results indicate that diffractogram of BC film after chemical pretreatment, the crystal size of BC film reduce from 10.01 nm (without treatment) to 3.67 nm, 3.62 nm, and 3.68 nm for pretreatment fo NaOH, H2O2, and BmimCl, respectively. The highest crystallinity of BC film was obtained by pretreatment using H2O2 with a crystallinity of 76.83%. The morphology of BC film indicated that pretreatment using NaOH, H2O2, and BmimCl cause peel of BC nanofiber so that the surface of BC film looks rougher and more porous. [ABSTRACT FROM AUTHOR]