Journal of Applied Research in Chemical-Polymer Engineering

Abstract Research subject: This research aims to revive outdated Kevlar fabrics for reuse in the manufacturing of polymer-based composite parts. As a polymer fiber with high tensile strength and significant resistance to impact and heat, Kevlar is used in various industries, including automotive, aerospace, and protective equipment manufacturing. This type of reinforcement alone does not give a good bond with polymer resins, and to create a strong bond, a conciliator (sizing agent) is used, which has a useful life. The physical and mechanical properties change over time due to environmental influences such as humidity, ultra-violet rays, and high temperature.
Research approach: In this research, among the thermal, mechanical, chemical, plasma, nanoparticles, and layering methods, the chemical method was chosen to revive outdated Kevlar fabrics. For this purpose, at first, three waste fabric samples were selected and finally, the tensile properties of regenerated and non-regenerated fabrics were compared according to the ASTM D638 standard tensile test.
Main results: The results showed that the chemically regenerated fabric had about 11.3% more tensile strength than non-regenerated fabrics, and the chemical regeneration process positively improved the mechanical properties of old Kevlar fibers. This achievement paves the way for the reutilization of aged fibers in advanced structures. This shows that the chemical regeneration process not only increases the mechanical strength of materials, but can also positively affect their durability and stability against environmental factors. In addition, this research provides an economic and ecological method for reviving old fibers, providing a basis for reducing industrial waste and reusing polymer materials.

Abstract The protective coatings and flexible packaging industries play a pivotal role in modern society. They contribute to human health, safety, comfort, and economic progress. Initially, these materials were produced from naturally occurring components; however, they have since evolved into intricate compositions designed to fulfill various performance criteria.  Currently, the majority of these materials are discarded in landfills, and their carbon content cannot be recovered or reused efficiently. In recent years, database statistics show a steady increase in research related to functional coatings, reflecting the growing interest in innovative and sustainable solutions. The global focus on reducing reliance on fossil fuel products and mitigating environmental impacts is accelerating efforts to integrate renewable resources into coating technologies. These technologies utilize bio-based raw materials, including biopolymers and natural oils, as well as biodegradable materials derived from microorganisms, plants, and animals. To address environmental concerns, leading coatings and packaging manufacturers have launched scientific and technical research to improve the sustainability of their products. Ongoing research focuses on the development of bio-derived materials, the adoption of energy-efficient manufacturing processes, the design of long-lasting products, and the use of sustainable and renewable resources. In addition, companies seek financial and competitive advantages through proactive internal initiatives. This highlights the urgent need for a circular economy model that overcomes current limitations in recycling and decomposition technologies. The authors stress the significance of comprehending society's tendency to prioritize and value sustainability, along with the financial and competitive advantages that may result from adopting proactive in-house efforts.