Challenges and Opportunities of Self‐Healing Polymers and Devices for Extreme and Hostile Environments

To meet increasing demands for alternatives to fossil-based chemicals, environment-friendly and renewable energy materials are of great importance. Biomass-derived 2,5-bis-(hydroxylmethyl)furan (BHMF) has the potential to partly substitute petroleum-based aromatic diols during polymerization. This paper summarizes recent research on the synthesis of BHMF by the reaction of hydrogen from biomass-based 5-hydroxymethylfurfural through different reduction routes, including the Cannizzaro reaction, catalytic hydrogenation, and catalytic transfer hydrogenation. Applications of BHMF as a direct material and intermediate in fabricating polyurethane, self-healing materials, resins, and more, which utilize ring-opening, double-bond addition, and oxidation reactions, are discussed briefly. Additionally, the challenges and opportunities in the formation and application of BHMF in the future are discussed.

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Electron microscopy studies of plasma-sprayed materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074276 ◽

1983 ◽

Vol 41 ◽

pp. 70-71

Author(s):

K.R. Subramanian ◽

A.H. King ◽

H. Herman

Keyword(s):

Plasma Spraying ◽

Substrate Surface ◽

Flame Temperature ◽

Ceramic Coatings ◽

Metallic Substrates ◽

Hot Plasma ◽

Almost All ◽

Plasma Sprayed ◽

Hostile Environments ◽

Plasma Spraying Process

Plasma spraying is a technique which is used to apply coatings to metallic substrates for a variety of purposes, including hardfacing, corrosion resistance and thermal barrier applications. Almost all of the applications of this somewhat esoteric fabrication technique involve materials in hostile environments and the integrity of the coatings is of paramount importance: the effects of process variables on such properties as adhesive strength, cohesive strength and hardness of the substrate/coating system, however, are poorly understood.Briefly, the plasma spraying process involves forming a hot plasma jet with a maximum flame temperature of approximately 20,000K and a gas velocity of about 40m/s. Into this jet the coating material is injected, in powder form, so it is heated and projected at the substrate surface. Relatively thick metallic or ceramic coatings may be speedily built up using this technique.

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Continuous hydrogenolysis of acetal-stabilized lignin in flow

Green Chemistry ◽

10.1039/d0gc02928a ◽

2021 ◽

Author(s):

Wu Lan ◽

Yuan Peng Du ◽

Songlan Sun ◽

Jean Behaghel de Bueren ◽

Florent Héroguel ◽

...

Keyword(s):

Steady State ◽

Challenges And Opportunities

We performed a steady state high-yielding depolymerization of soluble acetal-stabilized lignin in flow, which offered a window into challenges and opportunities that will be faced when continuously processing this feedstock.

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Autonomous self-healing polyisoprene elastomers with high modulus and good toughness based on the synergy of dynamic ionic crosslinks and highly disordered crystals

Polymer Chemistry ◽

10.1039/d0py01034k ◽

2020 ◽

Vol 11 (41) ◽

pp. 6549-6558

Author(s):

Yohei Miwa ◽

Mayu Yamada ◽

Yu Shinke ◽

Shoichi Kutsumizu

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Self Healing ◽

High Modulus ◽

Disordered Crystals ◽

Ionic Crosslinks

We designed a novel polyisoprene elastomer with high mechanical properties and autonomous self-healing capability at room temperature facilitated by the coexistence of dynamic ionic crosslinks and crystalline components that slowly reassembled.

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