No abstract

The development of chemicals from renewable sources as replacements for current toxic and unsustainable petrochemicals is an area of expanding study and interest. Phenolic epoxies derived from lignin, an underutilized resource generated as waste by the pulp and paper industry, and furanyl–amine epoxy curing agents derived from cellulosic biomass, are already proven independently to yield thermosetting resins possessing adequate thermal and thermomechanical properties. In this work, the union of the aforementioned technologies is examined to determine the properties and characteristics of such highly bio‐derived epoxy and amine thermosets. Resins with bio‐derived carbon content greater than 97% are synthesized and characterized via Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). Lignin‐derived epoxy resins are found to be compatible with a cellulose‐derived furanyl diamine curing agent to produce thermosetting resins with good thermomechanical and thermogravimetric properties, rivaling the levels of properties exhibited by similar commercial petroleum‐derived systems, indicating viability for replacing petroleum‐based polymers in high‐temperature applications.

Abstract

The stability of metal–organic frameworks (MOFs) in water affects their ability to function as chemical catalysts, their capacity as adsorbents for separations in water vapor presence, and their usefulness as...

Metal−ceramic nanocomposites exhibit exceptional mechanical properties with a combination of high strength, toughness, and hardness that are not achievable in monolithic metals or ceramics, which make them valuable for applications in fields such as the aerospace and automotive industries. In this study, interpenetrating nanocomposites of three-dimensionally ordered macroporous (3DOM) tungsten−silicon oxycarbide (W−SiOC) were prepared, and their mechanical properties were investigated. In these nanocomposites, the crystalline tungsten and amorphous silicon oxycarbide phases both form continuous and interpenetrating networks, with some discrete free carbon nanodomains. The W− SiOC material inherits the periodic structure from its 3DOM W matrix, and this periodic structure can be maintained up to 1000 °C. In situ SEM micropillar compression tests demonstrated that the 3DOM W− SiOC material could sustain a maximum average stress of 1.1 GPa, a factor of 22 greater than that of the 3DOM W matrix, resulting in a specific strength of 640 MPa/(Mg/m 3 ) at 30 °C. Deformation behavior of the developed 3DOM nanocomposite in a wide temperature range (30−575 °C) was investigated. The deformation mode of 3DOM W−SiOC exhibited a transition from fracturedominated deformation at low temperatures to plastic deformation above 425 °C.