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Bacterial cellulose (BC) is synthesized from extract of pineapple peel and Acetobacter xylinum as fermentation bacteria. This study aims to investigate the influence of graphene concentration on the morphology and crystalinity in bacterial nanocellulose (BNC) nanocomposites. To obtain bacterial nanocellulose (BNC), the previously manufactured pellicle BC was homogenized using a high-speed blender and a high-pressure homogenizer (HPH). Bacterial nanocellulose was combined with different concentrations of graphene (0.25, 0.5, and 1%), and then put into an ultrasonic homogenizer. Then, BNC-graphene solution was poured into a glass mold laminated with aluminium foil, and it was dried in an oven for 14 hours, 80°C. Scanning electron microscopy (SEM) was used to observe the morphology of nanocomposites membrane. X-Ray Diffraction is used to investigate the crystallinity of nanocomposites membrane. The structure of BNC-graphene nanocomposites membrane become more compact, according to the synthesized results. A few peaks at 2θ of 14.5°, 16.6°, 22.7° are seen in the XRD analysis, as well as a graphene diffraction pattern peak at 2θ of 13.7°. Nanocomposites membrane's crystallinity was reduced after graphene was added when compared to nanocomposites membrane without graphene. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BNC) composite membrane reinforced with titanium dioxide (TiO2) and addition polyethylene glycol (PEG) were analyzed in the study. Bacterial cellulose (BC) pellicle from pineapple peel waste extract. BC pellicle was cleaned with 1% NaOH. BC was mashed with a blender and carried out a high-pressure homogenizer (HPH) method of 5 cycles at a pressure of 150 bar, filtered through a vacuum filter. Composite membrane synthesized 10 grams BNC, 1% TiO2, and 1% PEG. All were mixed and dried in an oven for 14 hours at 80℃. Morphology and crystallinity were analyzed. SEM morphology of BNC membrane added with PEG made fibers look large because they were coated with PEG. BNC/ TiO2 added with PEG surfactant was able to disperse TiO2 evenly. Results of crystallinity membrane contained 4 diffraction peaks angle 2θ: 14.5°,16.8°, 22.6°, and 25.2°. Diffraction peaks BNC with BNC/PEG increase because PEG is a plasticizer making diffraction peaks larger. 1% TiO2 nanoparticles with the addition of 1% PEG caused crystallinity value and crystallinity index to decrease because the low interaction of PEG with TiO2 is hydrophobic, TiO2 is evenly dispersed in an aqueous solution and evenly distributed on the BNC matrix. [ABSTRACT FROM AUTHOR]

Bacterial Cellulose (BC) offers unique physical qualities such as high purity, crystallinity, and mechanical strength, as well as a high-water absorption capacity. Pineapple peel may be utilized as a source of cellulose, which is employed in a variety of applications. To improve the combination of BC and TiO2, TiO2 must be added, which affects the production of the cellulose membrane. The morphology of the membrane was studied using scanning electron microscopy (SEM). The membrane structure was studied using X-Ray Diffraction. SEM micrographs revealed that the control concentration increased the number of pores and had a small pore size of 81 nm, whereas the TiO2 concentration decreased the pore size. This drop is connected to the concentration increase. An XRD examination reveals the appearance of three peaks, the first at 14.12°, the second at 16.80°, and the third at 22.5°. The crystallinity index (Cl) and degree of crystallinity (Cr) increased with the addition of the specified concentration of TiO2, with the crystallinity index (CI) ranging from 66.8% to 76.1% and the degree of crystallinity (Cr) ranging from 50.3% to 68.6%. [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]

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]

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]

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]