Acoustic, tomographic, and morphological properties of bismaleimide-modified PLA green composites

Abstract

The effect of N 0 -(o-phenylene)dimalemide and 2,2 0 dithiobis(benzothiazole) on the speed of sound, sound attenuation and loss factor, 3-D microstructure, fiber dispersion, and morphology of wood pulp-reinforced PLA composites produced by hot press was investigated. Analysis of the chemical composition and fiber length of the wood pulp fibers provided information about the mechanism of adhesion and crystallinity of the modified composites. It was found that the modified composites have quite similar sound attenuation values, whereas the 3-D tomography analysis suggests the creation of a closely compact, cross-linked microstructure with improved fiber dispersion at higher processing temperature. The occurrence of a uniform, single-phase morphology suggests good compatibility between N 0 -(o-phenylene)-dimalemide and 2,2 0 dithiobis(benzothiazole) to PLA. Fourier transform-infrared (FT-IR) spectrometry suggests the creation of a new bond involving scission of the N 0 -(o-phenylene)dimalemide molecule to PLA and/or wood pulp. XRD analysis showed that the largest increase in the crystallinity occurred in the modified PLA blends.

Characterization of microstructures in sisal fiber composites by Voronoi diagram

“…Therefore, improvement of interface adhesion and reduction of fiber polarity were able to effectively prevent the aggregation between the fibers, thereby enhancing fiber dispersion in the matrix. Raj et al 24 and Baltazar-y-Jimenez et al 25 had found the same result in their studies. From this table, with the same extrusion compounding, the tensile properties of composites were increased greatly with fiber treatments and the incorporation of MAPP, which mainly attributed to the improvement of interface adhesion and uniform fiber distribution.…”

Hybrid biocomposites with enhanced thermal and mechanical properties for structural applications

“…Larger difference between the theoretical values and the experimental results were observed for hybrid biocomposites. From the literature, this can be attributed to poor fiber–matrix adhesion or increased microstructure defects, and higher void frequency . These results suggest that hybrid biocomposites will exhibit less than optimal mechanical and thermal performance.…”

“…Sound absorption property of hybrid biocomposites were measured using scanning acoustic microscopy (SAM) at transmission frequency of 1–15 MHz as explained by Baltazar‐y‐Jimenez et al . For determination of fogging characteristics, SAE J1756 standard (photometric method) was used in Labthink FT‐F1 fogging tester.…”

Comparative studies of mechanical and morphological properties of polylactic acid and polypropylene based natural fiber composites

“…Now, many components of automobiles are fabricated using natural fiber based composites. [9][10][11][12] Polylactic acid (PLA), a corn derived, fully biodegradable polymer based natural fiber green composite, is becoming popular in existing areas of application, especially in exterior and interior components of automobiles. Though PLA is biodegradable and provides good esthetics and has good mechanical properties and easy processability, it is brittle in nature which limits its application in various areas.…”