Current Materials Science - Volume 12, Issue 1, 2019

Background: This era has seen outstanding achievements in materials science through the advances in natural fiber-based composites. The new environmentally friendly and sustainability concerns have imposed the chemists, biologists, researchers, engineers, and scientists to discover the engineering and structural applications of natural fiber reinforced composites. Objective: To present a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials. Methods: The patent data have been taken from the external links of US patents such as IFI CLAIMS Patent Services, USPTO, USPTO Assignment, Espacenet, Global Dossier, and Discuss. Results: The present world scenario demands the usage of natural fibers from agricultural and forest byproducts as a reinforcement material for fiber reinforced composites. Natural fibers can be easily extracted from plants and animals. Recently natural fiber in nanoscale is preferred over micro and macro scale fibers due to its superior thermo-mechanical properties. However, the choice of macro, micro, and nanofibers depends on their applications. Conclusion: This document presents a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials.

Background: The vital role of smart materials in the field of aircraft, spacecraft, defence, electronics, electrical, medical and healthcare industries involve sensing and actuating for monitoring and controlling applications. The class of smart materials are also named as active materials or intelligent materials or adaptive materials. These materials act intelligently based upon the environmental conditions. Structures incorporated with smart materials are named as smart structures. Methods: The principal objective of the present paper is to explore a comprehensive review of various smart materials viz. piezoelectric materials, Shape Memory Alloy, micro sensors and fibre optic sensors. The significance of these intelligent materials in various fields are also deliberately presented in this work from the perspective of Patents and literatures test data. Results: Smart Materials possesses multifunctional capabilities. The smart materials viz. piezoelectric materials, Shape Memory Alloy, micro sensors and fibre optic sensors are embedded with structures like aircraft, spacecraft, automotive, bridges, and buildings for the purpose of exhibiting Structural Health Monitoring system. Smart materials are finding increasing applications in the present aircraft, spacecraft, automotive, electronics and healthcare industries. Conclusion: Innovative ideas would become reality by integrating the any structure with Smart Materials.

Background: In this article, we have studied the effect of cellulose fibers ratio on the fiber matrix interface damage of biocomposite materials based on a Polypropylene (PP) matrix. Methods: Few patents on the effect of cellulose fibers ratio on the fiber-matrix interface damage of biocomposite materials were published. We have investigated this damage, using a metaheuristic simulation based on the two Weibull probabilistic models which successively described the damage of the fiber and the matrix, our objective function is presented by the Cox model. Results: The results of our genetic modeling confirm that the level of damage is related to the mechanical stresses applied to the five studied materials Cotton-Polypropylene, Jute-Polypropylene, Flax- Polypropylene, Ramie-Polypropylene and Aramid-Polypropylene. Our genetic modeling indicates that the rate of cellulose in each fiber has a significant influence on the progressive degradation of the interface. The numerical simulation compared to the result obtained by genetic algorithm for the Aramid- Polypropylene composite shows that the level of degradation of the interface is greater compared to other biocomposite materials and that Cotton-Polypropylene has a very low interface damage compared to other biocomposites (82.5% cellulose). Conclusion: It can thus be said that the model correctly took into account the degradation phenomenon of a unidirectional composite and biocomposite and our calculations coincide perfectly with the conclusions of Antoine et al. who determined that the rate of cellulose in each fiber participates in the improvement of the mechanical properties of biocomposite materials.

Background: Mould growth on coated wood products during shipment is the foremost apprehension for most of the wood industries in India. Well finished wood products tend to get deposited by staining moulds superficially in high humidity conditions during shipment. Though wood disfiguring fungi (stain moulds) normally have no significant effect on the mechanical properties of timber, they only affect the aesthetic appearance of the material without destructing the wood cell wall. This causes a huge economic loss to the manufacturer due to disfigurement of the appearance of wood products. Methods: The aim of this work is to test and enhance antimicrobial property of Nitrocellulose lacquer wood finish to prevent mould deposition on coated wood products. The work was carried out to screen and evaluate the antimicrobial activity of commercial Nitrocellulose lacquer. Several patents regarding antimicrobial activity of nano metal oxides have been visited. In order to enhance the mould resistance of this coating, its combinations with neem oil and ZnO nanoparticles were prepared and tested against the growth of staining moulds: Aspergillus niger and Penicillium sp. on the wood substrate of Melia dubia. The study was carried out for 500 hours under favorable conditions (Temperature and Relative Humidity (RH)) for the mould growth. The growth was analysed on the basis of surface area affected by stain moulds on coated wood samples. Results: The growth analysis data inferred that the ZnO nanoparticles had significant effect against the growth of stain moulds. The presence of ZnO nanoparticles increased the mould growth resistance of Nitrocellulose lacquer coating to a great extent compared to the ability of neem oil for the same. This finding demonstrates the potential use of nano ZnO for increasing the effectiveness of NC lacquer against mould growth without hampering its other properties. Conclusion: 1 % nano ZnO concentration in Nitrocellulose lacquer wood coating increased its efficacy against staining mould growth by 95 %.

Background: Natural fiber reinforced materials with polymer matrix finds many applications in industries due to its excellent property. Fiber laminate composite materials have been researched around the globe and were tested to determine its beneficial properties for specific purposes. These composite materials have improved to withstand external loads. However, drilling of composite has remained a difficult task because of its anisotropic material properties. Methods: In this study abaca and kenaf woven mat with the carbon woven mat are laminated using epoxy resin (HY 951) and hardener (LY556) as matrix element while preparing the hybrid composite materials. The drilling operations are carried out using automatic feed computer controlled vertical axis drilling machine. Results: It is found that the drilling force, delamination peel up and push out for the composite material depended on feed rates, drill bit diameters and speeds respectively. The optimal input parameters are obtained using Taguchi L27 orthogonal array, Response Surface Methodology (RSM) and Analysis Of Variance (ANOVA) methods. It is observed that lower feed, smaller drill diameter and moderate speed provided high quality drilled hole. The drilled-hole quality, drilling damages are observed by using profile projector. Conclusion: The following conclusion can be drawn from the present investigation on drilling of reinforced composite materials drilled in different conditions. Feed rate is the important factor compared to the feed and the tool diameter. When feed rate is increased, thrust force also increases. However, thrust force decreases when the cutting speed increases. Feed influenced the thrust force instead of speed and torque during drilling. The drilling induced damages are minimum during lower feed and lower diameter drill. Hence, lower drill diameter, lower feed rate and medium speed are more suitable for drilling the hybrid composites.