Direct methanol fuel cells (DMFCs) are an essential aspect of electricity and fuel concerns. Herein, we report a new combination of Palladium nanoparticles anchored on polydiphenylamine with reduced graphene oxide network (rGO/PDPA/Pd) nanohybrid synthesized via an in-situ chemical strategy. The rGO/PDPA/Pd electrocatalyst shows excellent electrocatalytic activity, lower oxidation potential (−0.1 V), improved current density (2.85 mA/cm²), excellent cyclic stability (94%), and longevity (1200 s) towards methanol oxidation reaction (MOR) in the alkaline medium, when compared to commercial Pd/C electrocatalyst. Significantly, the forward oxidation peak potential of rGO/PDPA/Pd electrocatalyst was shifted negatively by 110 mV as compared to commercial Pd/C electrocatalyst. These results suggest that rGO/PDPA/Pd electrocatalyst is considered as an effective anode catalyst for DMFCs.

With the escalation in continuous human curiosity, massive research work is going on in the field of inflatable structures and inflatable systems. These inflatable structures offer a great advantage for the building of emergency air shelters for civilian and military, industrial fuel and gas storage tanks, life rafts, lifeboats, etc. Even, more advanced inflatables like hull structure for lighter-than-air systems (LTA) and inflated radomes are employed in the defence sector. The advantage of inflatable structures lies on their excellent mechanical strength, lightweight, durability and they can be stored in a small volume. Specialty elastomers play an important role in developing inflatable structures because of their excellent properties towards weather resistance, UV and ozone resistance, stability against aging, and oxidation. In addition, they show good gas and vapour barrier properties. In the beginning of this review article, the structure and properties of specialty elastomers selected in this study have been discussed and then the gas transport mechanism through polymeric material is described. In the last part, the development of diverse types of inflatable systems used in industry, defence, and marine applications have been highlighted. More attention is given to the advanced application of inflatables in the defence sector. Throughout this review work, various literature and published work related to specialty elastomers application in inflatable systems have been reviewed. The main emphasis of this study is on the structure, properties and application of specialty elastomers in the advancement of inflatable structures.

Continuous lattice fabrication is a newly introduced method for additive manufacturing of fiber-reinforced thermoplastic composites that allows to deposit material where it is needed. The success of this technology lies in a printing head in which unconsolidated continuous fiber-reinforced composite is pulled through a pultrusion die before the material is extruded and deposited out of plane without the use of supporting structures. However, state-of-the-art composite feedstock like commingled yarns shows limits in achievable material quality and part dimensions due to the underlying fiber architecture where thermoplastic fibers are mingled with reinforcement filaments. Hybrid bicomponent fibers overcome these constraints because each individual reinforcement filament is clad in a thermoplastic sheath. This results in absence of time-consuming fiber impregnation steps that would negatively effect void content and material quality.

This study compares the material quality of pultrudates made from hybrid bicomponent fibers to that of commercially available commingled yarns at various processing conditions. Experiments are reported in which polycarbonate composite profiles with a diameter of 5 mm containing 50 vol% to 60 vol% E-glass fibers are pultruded at different die filling degrees, mold temperatures and pultrusion speeds. The results show that the pultrudates obtained from hybrid bicomponent fibers have lower void content than those manufactured under the same conditions from commingled yarns. We assess this to be caused by the difference in consolidation mechanism which in the case of the hybrid bicomponent fibers is dominated by coalescing of the thermoplastic sheaths compared to the Darcian flow-dominated consolidation of commingled yarns.

Laser sintering is a commonly used Additive Manufacturing (AM) technique applicable to a variety of applications in fields such as the automotive industry, healthcare, and consumer goods. As well as offering mechanical properties suitable for end-use part production, polymer laser sintering can produce more complex structures than many other AM techniques since it does not require support structures, and parts can be stacked in the build area for more efficient processing. A wide range of polymers should theoretically be processable by laser sintering. However, in practice this is not the case, with only a small number of polymers currently able to be processed reliably and consistently. This paper reviews research that has been undertaken to increase the processability, mechanical properties and functionality of laser sintering polymers through the addition of a range of organic and inorganic nanofillers. It examines key challenges, including dispersion of the nanophase, and methods that have been developed to overcome them. The effects of the nanophase on processability are explored, as well as the importance of key processing parameters. The latest developments on techniques for production of nanocomposite powders and characterisation of parts are discussed. The final properties of laser sintered parts that have been achieved and their potential applications are highlighted, and the current challenges and potential directions for future research are discussed.

The dramatic situation with the environmental impact of plastics waste we observe nowadays is related with their inherent peculiarity as materials – they do not change substantially their properties after converting into waste even into litter. Just this their peculiarity could help for partial solution of the problem – to convert the plastics waste via recycling into valuable materials and thus to reduce the amount of plastics litter. As a possible technology of polymer recycling the concept of microfibrillar composites (MFCs) is discussed when blends of two non-miscible polymers are melt blended, extruded, cold drawn and further compression- or injection molded for manufacturing of polymer-polymer composites. The MFC based on PET from Coca Cola bottle and low-density polyethylene are characterized by superior mechanical properties achieved via cold drawing.

It is stressed that the recycling does not solve the problem of the negative impact of plastics on the environment, it only postpones this solution. This is because after the end-of-life of the recycled plastics they are converted again in waste or litter.

Carbon fiber reinforced polymers (CFRP) offer outstanding lightweight potential and can play a key role for modern energy and mobility concepts. However, production of carbon fibers is energy- and cost-intensive, while at the same time waste rates of common manufacturing technologies are quite high and repair possibilities for damaged parts still limited. Therefore, holistic recycling approaches are urgently required in order to reach acceptable cost-efficiency and sustainability. What makes the recycling so challenging, is the fact that true recycling, i.e. re-usage of fibers in high-performance composites, requires preservation of a high fiber length and enabling of accurate fiber orientation. This generates a trade-off between the best possible exploitation of the fiber properties and the effort to minimize the recycling costs. Hence, this paper does not only give a brief overview of technologies to recover carbon fibers from waste and to process them to new CFRP components. In addition, different approaches are presented, that exploit the specific characteristics of semi-finished products based on recycled carbon fibers, in order to achieve process- or material-related multifunctionality. This includes quasi-plastic deformation behavior (enables deep-drawing or curved tow placement), improved surface quality through reduced fiber print-through, robust resin impregnation through supersaturated nonwovens, and high energy absorption.