Water absorption pattern and dimensional stability of oil palm fiber-linear low density polyethylene composites

Development and Characterization of Natural-Fiber-Based Composite Panels

The emphasis on sustainability in materials related to the construction and transportation sectors has renewed interest in the usage of natural fibers. In this manuscript, a different perspective is taken in adopting oil palm fibers (OPF) to develop composite panels and understand their acoustic, mechanical, and water susceptibility (including warm water analysis) properties to provide an insight into the potential of these panels for further exploration. The binder for these composite panels is a water-based acrylic resin, and for reinforcement purposes, fly ash and other metal oxides are used. It is shown that the presence of fibers positively influences the acoustic absorption coefficient in the critical mid-frequency range of 1000-3000 Hz. Even the noise reduction coefficient values highlighting the octave band are higher by more than 50% in the presence of fibers as compared to traditional refractory boards. Quasistatic indentation and drop-weight tests have also highlighted the excellent performance of the composite panels developed in this work. Though the water immersion tests on composite panels and subsequent analysis showed relatively minor changes in their performance, the immersion of the panels in caustic warm water for 56 days has resulted in their severe degradation with a loss of more than 65% in flexural strength.

Bio-based composites fabricated from wood fibers through self-bonding technology

Green composite processing technology of wood fibers is an inevitable choice for global sustainable development. In this research, waste poplar powder with different particle sizes was used to prepare glue-free biocomposites with good mechanical and waterproof properties by hot-molding. The biocomposites made of larger size wood powder had better tensile strength (40.3 MPa) and the biocomposites made of smaller size wood powder had the greater bending strength (50.5 MPa). The thickness swelling rate of the biocomposites was only 4.26% after soaking in water for 24 h. The cross-section morphology of the biocomposites showed that the cell wall collapses enhanced the interfacial bonding. Chemical analysis showed that lignin repolymerized with cellulose and hemicellulose for the vitrification transition. In addition, the biocomposites with excellent mechanical properties had no formaldehyde release, which can replace the traditional density boards made of adhesives and applied as furniture materials and in line with the concept of cleaner production.

Taguchi Method and Taguchi-Pareto Scheme to Evaluate Diffusivity during the Development of Orange Peel Epoxy Composites

The diffusion parameters of orange peel epoxy composites are important elements in composite structure in that they explain how fast water and other fluids can diffuse through the composites as a sign of integrity test. In this article, we defined the optimal parametric settings for diffusivity parameters of orange peel epoxy composites. The Taguchi optimisation method used obtained an optimal parametric setting of P4Q4R1 in experiments conducted for three and seven days, respectively. The analysis of variance revealed significant contributions made by the initial and final weights, while the thickness parameter was found to be less significant. A variant of the Taguchi method called Taguchi-Pareto was introduced, which also underscores the thickness parameter as not economical to optimality. The specifications and dimensions obtained by Taguchi method or its variant may be useful design engineers when contemplating on how to reduce diffusivity and water uptake of composites.

Assessment of the physical properties of banana pseudo stem/ABS composites

The physical properties of Banana Pseudo Stem (BPS) reinforced Acrylonitrile Butadiene Styrene (ABS) composites with different fiber weight percentages were studied. BPS fibers were pretreated by using Sodium hydroxide solution with 5% concentration for 24 hours. ABS/BPS composites were prepared with 0, 10, 20 and 30 wt. % fibers. The Moisture Content (MC %) and Water Absorption (WA %) for BPS fiber were studied. The water absorption (WA %) and Thickness Swelling (TS %) of the composites were investigated. The scanning electron microscope (SEM) observation for fracture surfaces was also studied. The Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) analyses were used to measure the thermal stability and glass transition temperature (Tg) of BPS/ABS composites. Moreover, the melt flow index (MFI) and dimensional stability tests for the composites were studied.

3D Printable Filaments Made of Biobased Polyethylene Biocomposites

Two different series of biobased polyethylene (BioPE) were used for the manufacturing of biocomposites, complemented with thermomechanical pulp (TMP) fibers. The intrinsic hydrophilic character of the TMP fibers was previously modified by grafting hydrophobic compounds (octyl gallate and lauryl gallate) by means of an enzymatic-assisted treatment. BioPE with low melt flow index (MFI) yielded filaments with low void fraction and relatively low thickness variation. The water absorption of the biocomposites was remarkably improved when the enzymatically-hydrophobized TMP fibers were used. Importantly, the 3D printing of BioPE was improved by adding 10% and 20% TMP fibers to the composition. Thus, 3D printable biocomposites with low water uptake can be manufactured by using fully biobased materials and environmentally-friendly processes.