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Herein, poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-(methacrylohydroxyhexane azobenzene)s) (P(FHEMA-co-MAZOHE)s) were prepared by random copolymerization and were characterized by proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC) to confirm the structures and molecular weights respectively. Thermal variations were analyzed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) techniques. Finally, redox and photo stimuli-responsive properties were confirmed by cyclic voltammetry (CV) and ultraviolet–visible spectroscopy (UV–vis) respectively. The results revealed that (P(FHEMA-co-MAZOHE)s) can be useful as information storage materials.

The Burning rate of a solid propellant predominantly influences its internal ballistic behavior and it has been well known that incorporation of small quantities of certain classes of organic and inorganic substance to a propellant can drastically alter its burning rate characteristics. The inclusion of energetic materials and burning rate catalysts (BRCs) from the metallocene family (e.g., ferrocene (Fc) and 2,2-bis (ethylferrocenyl) propane also known as catocene (Cat)) has been a promising avenue for efficiently increasing the burning rate of propellants. Fc-based materials are dominantly used as burning rate catalysts in solid propellants because of their low volatility, higher compatibility with organic binders, microscopic homogeneities in distribution, broad range of burning rate adjustments, better ignitability and distinct catalytic features. However, in solid composite propellants, Fc-based polymers and derivatives show undesired properties of high migration, that is travelling out from propellant grain to surrounding insulation material on prolong storage, evaporation or sublimation loss during processing and curing as well as phase separation by crystallization in low-temperature applications, limiting their application as BRCs. This article outlines the latest synthetic advancements in the field of Fc-based BRCs, as well as highlighting their catalytic and anti-migration mechanisms.

Efficient composite solid propellants possess stable burning rate (BR) and low-pressure exponents. To achieve the ideal performance of propellants, addition of burning rate catalysts (BRC) to the propellants system is one of the best choice. BRC are of tremendous notable significance in composite propellants for their distinctive feature to positively enhance the operational efficiency of solid propellants. In this regard, many valuable kinds of BRC have been synthesized. Due to their better ignitability, ferrocene-based compounds are well-known class of BRC. However, considerable migration and diffusion tendency of this developed class of useful compounds during storage procedures of composite solid propellants limit their practical use as an ideal BRC. This article reviews recent advances in the active field of Fc-based derivatives. In gradual addition, this article also highlights recent progress of Fc-based derivatives as a BRCs and adequately discuss their significant improvements in anti-migration properties.

Different copolymers (poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-methacrylo-4-aminoazobenzene-co-methacrylic acid)s) (P(FHEMA-co-MAZO-co-MAA)s) were synthesized and their different properties were analyzed in this work. Methacrylic acid was introduced as a side group to possibly affect the photostability. The synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR) spectroscopy and gel permeation chromatography (GPC). Thermal studies were performed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) analysis, which showed that the copolymers were thermally stable under the operating conditions of the information storage devices. Redox studies and photoresponsive studies were performed by CV technique and UV/vis spectroscopy which showed that these copolymers contained good redox and photoresponsive properties. The obtained results paved the way towards the four states information storage of the materials.