Polymer composites from natural fibers and recycled waste surgical masks during COVID-19 pandemic

The crucial role of face masks is highlighted in our day-to-day life during the COVID-19 pandemic. Polypropylene (PP)-based disposable face masks are widely used to hold back viral transmission. The discarded masks can create a huge burden of contamination on the environment. The purpose of this work is to recycle and reuse discarded masks to reduce environmental pollution. A simple and innovative technique to recycle surgical masks into composites of higher mechanical strength and antimicrobial properties is explored to reuse in packaging materials and cutleries. The surgical masks composed of PP fibers are recycled to use as a matrix material to reinforce with sisal and hemp fibers. The hot compression molding technique is used to sandwich the PP masks with natural fibers. The tensile strength of the composites is remarkably increased by 197% and 305% for sisal fiber composites and hemp fiber composites, respectively. The tensile elongation also increased to 574% for sisal fiber composites. The resulting composites exhibit notable antimicrobial properties against Staphylococcus aureus, a pathogen responsible for common staphylococcal food poisoning. The composites are found to be suitable to use as food contact cutleries and packaging materials.

Tunable Mechanical, Electrical, and Thermal Properties of Polymer Nanocomposites through GMA Bridging at Interface

Polymer nanocomposites (PNCs) have become an exciting field of current research and have attracted a huge interest among both academia and industry during the last few decades. However, the multifunctional single-nanocomposite film exhibiting the combination of desired structure and properties still remains a big challenge. Herein, we report a novel strategy to address these problems by using versatile polymer glycidyl methacrylate (GMA) as a bridging medium between the filler and the polymer matrix, resulting in high density of interfaces as well as strong interactions, which lead to generation of tunable thermal, mechanical, and electrical properties in the materials. The nanocomposites prepared by GMA bridging exhibit the remarkable combination of thermal (T _d = 342.2 °C, T _g = 150.1 °C ), mechanical (E = 7.6 Gpa and H = 0.45 Gpa ) and electrical (σ = 3.15 × 10^-5 S/cm) properties. Hence, the conjugation approaches related to GMA bridging facilitate a new paradigm for producing multifunctional polymer nanocomposites having a unique combination of multifunctional properties, which can be potentially used in next-generation polymer-based advanced functional devices.

Swift Heavy Ion Irradiation as a Tool for Homogeneous Dispersion of Nanographite Platelets within the Polymer Matrices: Toward Tailoring the Properties of PEDOT:PSS/Nanographite Nanocomposites

Performance of the polymer nanocomposites is dependent to a great extent on efficient and homogeneous dispersion of nanoparticles in polymeric matrices. The dispersion of nanographite platelets (NGPs) in polymer matrix is a great challenge because of the inherent inert nature of the NGPs, poor wettability toward polymer matrices, and easy agglomeration due to van der Waals interactions. In the present study, attempts have been made to use a new approach involving the irradiation of polymer nanocomposites through swift heavy ion (SHI) to homogeneously disperse the NGPs within the polymer matrices. Poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (

PEDOT

PSS)/nanographite nanocomposite (NC) films prepared by the solution blending method were irradiated with SHI (Ni ion beam, 80 MeV) at a fluence range of 1 × 10(10) to 1 × 10(12) ions/cm(2). XRD studies revealed that ion irradiation results in delamination and better dispersion of NGPs in the irradiated nanocomposite films compared to unirradiated films, which is also depicted through SEM, AFM, TEM, and Raman studies. In the irradiated polymer nanocomposite films, the conformation of PEDOT chains changes from coiled to extended coiled structure, which, along with homogeneously dispersed NGPs in irradiated NCs, shows an excellent synergistic effect facilitating charge transport. The remarkable improvement in conductivity from 1.9 × 10(-2) in unirradiated NCs to 0.45 S/cm in irradiated NCs is observed with marked improvement in sensing the response toward nitroaromatic vapors at room temperature. The temperature induced conductivity studies have been carried out for

PEDOT

PSS/nanographite NCs to comprehend the charge transport mechanism in NC films using the 3D Mott variable range hopping model also. The study reveals SHI as a novel method, addressing the challenge associated with the dispersion of NGPs within the polymer matrix for their enhanced performance toward various applications.