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• The mixture of boric acid and borax slow down PLA's fire speed by roughly 66 %. • Thermal degradation temperature lowered by the addition of boron compounds to PLA. • Flexural and Young's modulus prominently rise by roughly 20 % and 22 %, respectively. • 5 wt% boron compounds reinforced composites have better mechanical–thermal results. This study aims to understand how ulexite, boric acid-borax mixtures (1:1), and zinc borate fillers affect the thermal and mechanical properties of the poly (lactic acid) (PLA). For this purpose, three different boron fillers were added to the PLA matrix at four different concentrations of 3 %, 5 %, 8 %, and 12% wt. UL-94 test was conducted to comprehend the impacts of boron fillers on the fire resistance of the biocomposites. Thermogravimetric analysis was applied to determine the thermal stability, mass loss, and decomposition temperature of the samples. The biocomposite's significant mechanical properties, such as tensile strength, flexural strength, Young's modulus, and elongation at break, were assessed using tensile and three-point bending tests. Although the tensile and flexural strengths of PLA reduced, flexural and Young's modulus rose by roughly 20 % and 22 %, respectively, with rising boron filler rates. [ABSTRACT FROM AUTHOR]

This work deals with fibrous biocomposites prepared by using nettle and poly(lactic acid) fibers and employing carding and compression-molding processes. The role of carding process in determining the tensile strength of the biocomposites was analyzed. The tensile, bending and impact properties of the biocomposites were found to increase initially with the increase of nettle fiber content till 50 wt% and decrease afterwards. The thermogravimetric analysis inferred that the thermal stability of the biocomposites increased with the increase of nettle fiber content. The dynamic mechanical analysis showed that the biocomposites exhibited high storage modulus, low loss modulus, and low damping factor. Further, the biocomposites exhibited excellent biodegradability and their biodegradability increased with the increase of nettle fiber content. Overall, the biocomposite prepared with equal weight proportion of nettle and poly(lactic acid) showed high potential for automotive dashboard panel application. [ABSTRACT FROM AUTHOR]

Natural fibers are not as rigid as glass or carbon fibers. During composites extrusion and injection molding, they tend to bend and twist in the polymeric matrix, thus resulting in fiber waviness and decreased mechanical properties of natural fiber composites. The most widely used models for the estimation of interfacial shear strength (IFSS) and elastic modulus, which consider the fiber aspect ratio and mechanical properties of the fiber and matrix, do not consider these important features. In order to account for fiber waviness, an effective fiber length is proposed in this paper. The undulation of the fibers is approximated with a sinusoidal arc along with a calculated new length. The proposed correction factor depends on the wavelength and amplitude of the wave approximating the fiber. To verify this method, blends of polylactic acid (PLA) and polycarbonate (PC) (prepared with and without an interchange reactions catalyst) with addition to various percentages of cellulosic fibers (5 wt%, 10 wt% and 15 wt%) have been prepared and characterized. It has been demonstrated that by considering the corrected length values, it is possible to predict the mechanical properties and the effective reinforcement attained in the composites by using the most widely used models. In particular, the prediction of the elastic modulus is slightly affected by this correction, whereas the calculation of IFSS is strongly dependent on it. [ABSTRACT FROM AUTHOR]

This work aims the manufacture of injection molded polylactic acid (PLA)-based magnetic biocomposites, presenting an alternative approach to enhance the magnetic susceptibility of PLA-based biocomposites without resorting to the exclusive incorporation of magnetic nanoparticles whose long-term side effects are still unclear. Magnetic biocomposites were obtained by incorporating 5 wt% of iron doped biphasic calcium phosphate (FeBCP) powders into the PLA matrix and compared with similar composites containing 2 and 5 wt% of non-doped BCP powder, as well as neat PLA. The chemical, thermal, mechanical, and magnetic performances were evaluated. Biodegradability according to two sterilization methods used and cytotoxicity were also assessed. The composites with FeBCP exhibited a typical ferromagnetic-like behavior and presented a superior tensile strength even with low concentrations of FeBCP, when compared to PLA or non-doped composites, besides being cytocompatible. The presented proof of concept paves the way for future developments of new magnetic PLA-based biocomposites for biomedical applications. [Display omitted] • New generation of magnetic PLA-based composites preventing the use of MNP. • Magnetic BCP powders improved the mechanical performance of PLA-based composites. • Homogeneous distribution of magnetic BCP-based powders within PLA matrix was attained. • BCP powders improved the thermal stability of PLA. [ABSTRACT FROM AUTHOR]

Environmental awareness of the global waste problem has driven the development of new green composites made from either renewable or biodegradable materials. Among the variety of available green composites, natural composites based on poly-lactic acid (PLA) have shown noteworthy performance due to their short degradation time after disposal, good strength, and ease of processing by conventional methods. In particular, green composites manufactured with PLA matrix reinforced with Manicaria Saccifera fabric (MF) display mechanical properties that have shown to be very competitive compared with similar materials. In this study, the tensile properties of a green composite of PLA reinforced with MF are optimized by using a Taguchi method approach. The processing parameters, fabric chemical treatment parameters, compression molding parameters, and fiber content are analyzed simultaneously to yield the optimum biocomposite properties. The predicted optimum parameters are experimentally verified. Tensile tests and scanning electron microscope (SEM) analysis are used. Significant improvements on both the tensile strength (114.2%), and the elastic modulus (120.6%) of the biocomposite are achieved. [ABSTRACT FROM AUTHOR]