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"Green" composites were fabricated using modified sisal fibers and agro‐waste derived resins from nonedible protein and starch in a simple and cost‐effective manner. Sisal fibers were modified using a novel combination of mercerization followed by heat treatment under a pre‐determined tension which improved their Young's modulus by over 200% (from 5.5 to 16.7 GPa) and tensile strength by about 50% (from 300 to 450 MPa). The non‐edible protein and starch were extracted from defatted karanja (Pongamia pinnata) and mango (Mangifera indica) seed cake wastes, respectively, to prepare the green resins. Composite specimens were fabricated using as‐received and modified fibers and agro‐waste derived resins using a hand lay‐up process followed by hot‐pressing. The tensile properties of the composites made with modified fibers showed significant improvement as compared to the composites made with as‐received fibers as well as other edible starch or protein‐based sisal composites. POLYM. COMPOS., 40:99–108, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The research and development of graphene and graphene‐based materials have been significantly increasing since they were invented. However, in many industries, the applications of graphene nanoflakes are still few, compared with other materials. This study presents the fabrication of highly conductive graphene thin film (GTF) papers to reduce the possible damage of lightning strikes on composite structures. Three concepts were presented in this project: (1) fabrication of a highly conductive functionalized nanosize GTF, (2) incorporation of the GTF into carbon fiber‐reinforced composite panels, and (3) introduction of 3D stitching concepts into composite structures to protect against the effects of lightning strikes. Experimental studies have shown that the highest electrical and thermal conductivity values measured on GTF papers are approximately 1,800 S/cm and 425 W/m.K, respectively. After GTF was incorporated into the carbon fiber‐reinforced composites, some delamination was observed between the GTF and the composite. Therefore, the 3D stitching concept was introduced to reduce this delamination. Four stitch configurations with different stitch lengths, thread‐to‐thread thicknesses, thread tensions, and thread thicknesses were used. Then, tensile tests were carried out on the prepared unidirectional fiber composite test coupons. Although the delamination was completely eliminated, tensile strength on some of the test configurations was reduced. This study will be useful in increasing the electrical and thermal conductivity values of composite surfaces in aircraft and wind energy industries. POLYM. COMPOS., 40:E517–E525, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Nanoparticles have received significant attention from the scientific community because of their exceptionally large surface-area-to-volume ratios along with their extraordinary properties, in comparison to bulk materials of the same kind. These materials have unique thermal, optical, electrical, mechanical, electronic, and biological properties, which make them suitable candidates for many applications with significantly improved performance. Carbon black (CB) is a powdered form of elemental carbon that is produced by the partial combustion or thermal decomposition of solid, liquid, or gaseous hydrocarbons under a controlled environment. Its physical appearance is a spherical-shaped, finely divided pellet or powder form of amorphous carbon that has a high surface-area-to-volume ratio. It's primarily used as a reinforcing agent in vehicle parts and rubbery automotive products (e.g., tires, tubes, tread, belts, hoses, miscellaneous) and non-automotive industrial applications (e.g., molded items, laser printing, and extruded products), which are employed in many countries, and consume approximately 90% of CB production. The remaining 10% of CB is divided among other special applications that include everyday products, such as coatings, plastics, lithium ion batteries, vehicles for large hydrogen storage, chemical sensors, super capacitors, and ultra-violet protection. Carbon black is mass-produced by controlled vapor-phase pyrolysis and the incomplete combustion of gaseous or liquid hydrocarbons. This book chapter summarizes recent advances in the fabrication, characterization, properties, and applications of CB nanoparticles in various industries. The new plasma technology for the production of superior quality CB has been studied extensively and compared with other techniques. [ABSTRACT FROM AUTHOR]