Effect of curing reaction types on the structures and properties of acetylene-containing thermosets: towards optimization of curing procedure

High-temperature thermosets are usually prepared from resins containing alkynyl groups, and their properties depend much upon the curing process containing various types of curing reactions. However, how the curing process affects the properties remains unclear due to the complicated curing reactions. We used molecular dynamics simulations to investigate the effect of curing reaction types, including cyclotrimerization, Diels-Alder reaction, and radical reaction, on the structures and properties of imide oligomers terminated with alkynyl groups. The results show that the cycloadditions such as cyclotrimerization and Diels-Alder reaction endow the thermosets with rigid structures and high moduli. Compared with the cycloadditions, the radical reaction enables the formation of flexible cured structures, which can enhance the toughness of thermosets. The differences in thermal and mechanical properties caused by different curing types were elucidated by the relaxation processes of fragments in these cured systems and were explained by the variation of torsion energy in different curing forms. As this work aims to optimize the curing procedure to obtain high-performance resins with desired properties, different curing procedures were finally designed according to the theoretical studies, and the obtained cured polymers show significant differences in the properties from different curing ways. The results can guide the preparation of desired thermosetting resins by tuning the curing procedure.

Study on the Superhydrophobic Properties of an Epoxy Resin-Hydrogenated Silicone Oil Bulk Material Prepared by Sol-Gel Methods

A superhydrophobic material was prepared by a simple and easily accessed sol-gel method using epoxy resin (E-51) and γ-aminopropyltriethoxysilane (KH-550) as the precursors, aqueous ammonia (NH₄OH) as the catalyst and hydrogenated silicone oil (PMHS) as the hydrophobic modifier, and then pelleting the final product. The morphologies, surface chemical properties and thermal stability of the superhydrophobic bulk materials were characterized by scanning electron microscopy, Fourier infrared spectrometry and thermal analyzer. The hydrophobic properties and repairability of the as-prepared materials were also studied. The results showed that the prepared epoxy resin-hydrogenated silicone oil bulk materials were composed of tightly bound nanoparticles with a size of 50–100 nm in diameter. The material showed excellent superhydrophobic properties with a surface contact angle of 152°. The material also had good thermal resistance with a heat-resistant temperature of 300 °C and showed good repairability. The epoxy resin-hydrogenated silicone oil bulk superhydrophobic material exhibited excellent performance and showed wide application prospects.

Effect of epoxy monomer structure on the curing process and thermo-mechanical characteristics of tri-functional epoxy/amine systems: a methodology combining atomistic molecular simulation with experimental analyses

A methodology, which combined molecular simulation with experimental research, was established to expound the performance of a tri-functional epoxy/amine system.

Synthesis of amine-polyglycidol functionalised Fe3O4@SiO2nanocomposites for magnetic hyperthermia, pH-responsive drug delivery, and bioimaging applications

We report the biocompatible Fe₃O₄@SiO₂@APG-F nanocomposite for drug delivery and hyperthermia applications. The Fe₃O₄@SiO₂@APG-F nanocomposite could serve as a good hyperthermia agent, drug delivery carrier, and fluorescent contrast agent.