Continuous Bamboo Fibers/Fire-Retardant Polyamide 11: Dynamic Mechanical Behavior of the Biobased Composite

A biobased composite was generated from bamboo fibers (BF) and a polyamide 11 (PA11) matrix. In order to fulfill security requirements, a PA11 already containing a flame retardant (FR) was chosen: This matrix is referred as PA11-FR. In this work, the effects of flame retardant (melamine cyanurate) on the composite properties were considered. In the calorimetric study, the glass transition and melting temperatures of PA11-FR were the same as those of PA11. The melamine cyanurate (MC) had no influence on these parameters. Thermogravimetric analysis revealed that PA11-FR was less stable than PA11. The presence of MC facilitated thermal decomposition regardless of the analysis atmosphere used. It is important to note that the presence of FR did not influence processing conditions (especially the viscosity parameter) for the biosourced composite. Continuous BF-reinforced PA 11-FR composites, single ply, with 60% of fibers were processed and analyzed using dynamic mechanical analysis. In shear mode, comparative data recorded for BF/PA11-FR composite and the PA11-FR matrix demonstrated that the shear glassy modulus was significantly improved: multiplied by a factor of 1.6 due to the presence of fibers. This result reflected hydrogen bonding between reinforcing fibers and the matrix, resulting in a significant transfer of stress. In tensile mode, the conservative modulus of BF/PA11-FR reached E’ = 8.91 GPa. Upon BF introduction, the matrix tensile modulus was multiplied by 5.7. It can be compared with values of a single bamboo fiber recorded under the same experimental conditions: 31.58 GPa. The difference is partly explained by the elementary fibers’ lack of alignment in the composite.

Mechanical Properties and Durability of Bamboo Fibers/Bamboo-Fiber-Mixed Spray Mortar for Slope Protection

Conventionally, short fibers such as steel and synthetic fibers have been mixed into spray mortar used for slope protection to enhance resistance against cracking and durability. However, in the quest of higher performance fiber-reinforced mortar with reduced impact on the environment, natural fibers such as bamboo fibers may play a vital role. Thus, the tensile strength and the bond strength of bamboo fibers used for spray mortar were examined by laboratory tests. The mechanical properties of bamboo-fiber-reinforced spray mortar were examined under cyclic wet and dry conditions along with its resistance against freezing and thawing by a spray test. It was confirmed that 0.75% mixture of bamboo fibers in spray mortar successfully improved mechanical properties and durability. These include adhesion strength to the base surface following exposure to cyclic wet/dry conditions and overall resistance against freezing/thawing. Moreover, higher compressive strength, flexural toughness and adhesion strength to the base surface were achieved by further mixing in vinylon fibers or fly ash in addition to bamboo fibers.

The Spatial Orientation and Interaction of Cell Wall Polymers in Bamboo Revealed with a Combination of Imaging Polarized FTIR and Directional Chemical Removal

The mechanical and physical properties of lignocellulosic materials are closely related to the orientation and interaction of the polymers within cell walls. In this work, Imaging Polarized FTIR, combined with directional chemical removal, was applied to characterize the spatial orientation and interaction of cell wall polymers in bamboo fibers and parenchyma cells from two bamboo species. The results demonstrate the cellulose in bamboo fibers is nearly axially oriented whereas it is almost transversely arranged in parenchyma cells. Xylan and lignin are both preferentially oriented alongside cellulose, but with less orientation degre in the parenchyma cells. After lignin removal, the average orientation of xylan and cellulose is little affected, suggesting a strong interaction between cellulose and xylan. Meanwhile, the alkaline treatment significantly weakens the orientation of lignin in both fibers and parenchyma cells, and more significant for the latter, indicating the easy-degradable nature of lignin in parenchyma cells. And, it seemed the lignin and xylan in fibers were more difficult to be removed as compared to parenchyma cells, supporting the assumption that stronger interaction exists between lignin and xylan in the fibers. In a word, it was believed parenchyma cells are more suitable for biorefinery owing to its less ordered and relatively loose molecular assembly, as compared to fibers.

Effects of Particle Size and Composite Composition of Carbon Microparticles as Reinforcement Components on Resin-Based Brake Pad Performance

This study aims to investigate the effect of particle size and composition of bamboo and clove leaves as reinforcement components on resin-based brake pad performance. Bamboo fibers contain cellulose and lignin, making them better mechanical properties compared to glass fibers. Clove leaves due to their containment of oil components can be used, playing roles in binding bamboo with resin material. In short, experiments were done by involving polymerization of polyester resin as an adhesive with methyl ethyl ketone peroxide (MEKP) at room temperature. The composition of polyester/MEKP/reinforcing components was fixed at a mass ratio of 10/1/1.76 and the particle size of the reinforcing components were 582 and 250 m. Reinforcing components were mixed carbonized bamboo fiber and dried clove leaves with a ratio of 4/1; 7/1; and 10/1. The results showed that smaller particles has better mechanical properties, and the more amount of bamboo particles give positive impacts on the material hardness. The best hardness value (reaching 24 N/cm2) and smallest pore volume (0.0213 cm3) were obtained when using the ratio of 10:1. While the smallest weight loss of mass at the rate of 0.1225 g/min was obtained by the ratio of 7/1. The largest friction coefficient and lowest wear rate were obtained by 4/1 with a value of 0.1108 and 1.08 g/s.mm2, respectively. This study demonstrates the use of biomass waste such as bamboo fiber and dried clove leaves as an alternative to asbestos and reduces the abundant waste of bamboo powder and dried clove leaves in Indonesia.

Cell Wall Pore Structures of Bamboo as Relation to Species and Tissue Types

Efficient convention of bamboo biomass into biofuel and biomaterials, as well as chemical treatment are both highly related to the porosity of cell wall. The present work characterizes the micropore and mesopore structure in cell walls of six different bamboo species and tissue types using CO2 and N2 adsorption. Two plantation wood species were also tested for comparison. Bamboo species normally showed lower cell wall porosity (2.64%-3.75%) than wood species (3.98%-5.06%), indicating a more compact structure for bamboo than wood. A distinct species dependence of cell wall pore structures and porosity was also observed. Furthermore, the cell wall pore structure and porosity are shown to be tissue-specific, as the parenchyma cells exhibit higher pore volume and porosity compared to bamboo fibers. The obtained results give new explanations on the known facts that both bamboo and bamboo fibers exhibit higher biomass recalcitrance as compared to wood and bamboo parenchyma cells, constructing the base of pretreatment optimization and subsequent processing for bamboo-derived biofuels and biomaterials.

THE STUDY OF BENDING BEAMS MECHANICALS PROPERTIES WITH MICRO REINFORCEMENT

research on fiber concrete is currently growing very rapidly. The alternative fibers used in the concrete mix-ture is to use natural fibers. In this study, researchers used bamboo fiber as a substitute for artificial fiber, where Bamboo has a good tensile strength. The aim of this study to increase beam strength in sustaining ex-ternal loads by added bamboo fibers. The content of fiber additional to the concrete mixture was 1.5% of the cement weight. The mix design of concrete using ratio of cement water 0.25. The plasticizer and filler added in the mixture with the content of 2% and 15% cement weight, respectively. Two reinforced concrete beam specimens and 24 concrete cylinder specimens used in the study. Tests carried out of 28 days, and 56 days for cylindrical concrete, while bending test conducted of CBR1 and CBR2 at 28 test life only. In study show that addition 1.5% bamboo fiber to reinforced concrete beams increased the flexural capacity and ductility of the beams

Adsorption properties and mechanism of uranium by three biomass materials

Wood fibers, bamboo fibers and rice husk were applied to the adsorption of uranium from aqueous solution to understand the uranium adsorption behavior and mechanism by these natural sorbents. The effects of time, adsorbent particle size, pH, adsorbent dosage, temperature and initial concentration were studied using batch technique. The adsorption mechanism was discussed by isothermal adsorption models, adsorption kinetic models. The results suggested that the three biomass adsorbents showed great efficiency of adsorption for uranium. The adsorption capacity of biosorbents of comparatively small particle size and large dosage is quite high. Uranium adsorption achieved a maximum adsorption amount at around pH 3 for wood fibers and bamboo fibers, and around pH 5 for rice husk. All isotherms fitted well to the Langmuir Freundlich and D-R equation, indicating that the adsorption process is favorable and dominated by ion exchange. Rice husk had a highest adsorption capacity, followed by bamboo fibers, while wood fibers had little uranium adsorption under the studied conditions, and the adsorption capacity was 12.22, 11.27 and 11.04 mg/g, respectively. The equilibrium data was well represented by the pseudo-second-order kinetics, indicating that the adsorption rate was controlled by chemical adsorption. Ion exchange was the main adsorption mechanism, and the exchange ions were mainly Na+ and K+.

STUDI PERBANDINGAN SIFAT MEKANIK SERAT BAMBU

Natural fibers have application in almost every item used in our daily routine and been contributing explicitly to the economic prosperity and sustainability in our lives. Among the natural fiber plants, bamboo is the most popular, because of its versatile applications and significant contribution to the environment. Bamboo fibers have been used in various application such as decoration, weaving, paper makin, textile, and high-performance composites for the past many years. They have several advantages such as superior tensile strength, low density, and high flexibility under flexible and compressive loads. In order to meet the requirements of each bamboo application, there is a need to study the mechanical properties of bamboo fibers. This study reviews mechanical properties of bamboo fibers for various species, extraction methods, plant age, sizes, and moisture contents. Keywords: bamboo fiber; bamboo extraction method; mechanical properties; mechanical testing; tensile strength AbstrakIndonesia kaya akan tanaman yang dapat diambil seratnya untuk diolah menjadi produk yang bermanfaat. Di antara tanaman penghasil serat alami, bambu adalah yang paling populer, karena memiliki aplikasi yang serba guna, mudah tumbuh, tidak memerlukan perawatan dan dapat mengurangi pencemaran udara. Serat bambu telah digunakan dalam berbagai aplikasi seperti dekorasi, perabot, tekstil, kertas dan komposit. Beberapa keunggulan serat bambu adalah memiliki kekuatan tarik yang besar, densitas yang rendah dan fleksibilitas yang tinggi. Dalam rangka memenuhi persyaratan masing-masing aplikasi dari serat bambu, diperlukan studi mengenai sifat mekanik serat bambu. Penelitian ini membandingkan beberapa penelitian yang sudah dilakukan mengenai sifat mekanik serat bambu berdasarkan spesies, metode pengolahan dari batang bambu menjadi serat, umur tanaman, ukuran serat dan kadar kelembaban. Serat bambu yang dihasilkan dapat memiliki sifat mekanik yang optimal jika bambu yang dipilih adalah dari spesies tertentu, memiliki kadar kelembaban yang rendah dan menggunakan metode ekstraksi yang tepat.

Comparison of colors, microstructure, chemical composition and thermal properties of bamboo fibers and parenchyma cells with heat treatment

The effects of heat treatment at various temperatures on mechanically separated bamboo fibers and parenchyma cells were examined in terms of color, microstructure, chemical composition, crystallinity, and thermal properties. The heat-treated parenchyma cells and fibers were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), chemical composition analysis, and thermogravimetric analysis (TGA). The results revealed that the colors of bamboo fibers and parenchyma cells were darkened as treatment temperature increased. The microstructure of the treated fibers and parenchyma cells slightly changed, yet the shape of starch granules in parenchyma cells markedly altered at a temperature of above 160 °C. The chemical compositions varied depending on the heat treatment temperature. When treated at 220 °C, the cellulose content was almost unchanged in fibers but increased by 15% in parenchyma cells; the hemicellulose content decreased and the lignin content increased regardless of fibers and parenchyma cells. The cellulose crystal structure was nearly unaffected by heat treatment, but the cellulose crystallinity of fibers changed more pronouncedly than that of parenchyma cells. The thermal stability of parenchyma cells after heat treatment was affected more substantially compared to fibers.