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Slag waste‐filled phenolic resin‐based automotive brake friction composites were formulated, fabricated, followed by mechanical, physical characterization, and tribo‐evaluation. According to economic commission for Europe regulation, the tribological performance of the composites was evaluated on a Krauss friction‐testing machine. The increase in slag waste content led to increased physical properties such as density, porosity, ash contents, and compressibility, whereas hardness, acetone extraction, and shear strength increased with increased phenolic resin content. The fade and friction performance has been observed to be highly dependent on the slag waste content, that is, both followed a consistent decrease with the increase in the phenolic resin content, whereas the frictional fluctuations have been observed to decrease with the increase in slag waste content. In particular, the composites containing 65 wt% slag waste and 5 wt% phenolic resin showed the highest friction coefficient (0.406), lowest fade (20.44%) and frictional fluctuation (0.209), but the wear (10.80 g) and disc temperature rise (618°C) remains highest. Composite with the lowest slag waste content of 50 wt% combined with the highest phenolic resin of 20 wt% showed higher recovery performance (120.63%), lowest wear (4.45 g) and disc temperature rise (536°C), but exhibits lowest friction coefficient (0.315) and friction stability (0.79) along with highest friction variability (0.60) and fluctuations (0.238). Friction and wear data analysis revealed the predominance of the fade factor for friction performance while the fade factor and disc temperature‐induced results significantly influence the wear performance. The worn surface micrograph showed higher phenolic resin‐filled composites form smooth contact plateaus that successfully reduced wear. [ABSTRACT FROM AUTHOR]

Insulating materials are ubiquitous in a built environment and play a critical role in reducing the energy consumed to maintain habitable indoor environments. Mineral wool insulation (MWI) products, including glass, stone, and slag variants, are the most widely used class of insulating materials in Europe and account for more than 50% of the total market by volume. MWI typically consists of two key components: a mesh of inorganic fibers that are several micrometers in diameter, and an organic thermosetting adhesive commonly referred to as the "binder." Traditional phenol‐formaldehyde‐urea (PFU) binders used in the manufacture of MWI are increasingly being scrutinized for the formaldehyde released during their manufacture and service lifetime. The recent classification of formaldehyde as a carcinogen by various safety organizations has accelerated a paradigm shift within the industry toward alternative binder technologies that minimize or indeed eliminate formaldehyde emissions. This review examines more recent strategies for achieving low‐ or zero‐added formaldehyde binders for MWI, with a particular focus on the patent literature. The chemistry underpinning traditional PFU binders is presented and compared to new strategies involving scavenging molecules that decrease formaldehyde emissions, as well as zero‐added formaldehyde binder technologies such as polyester, Maillard, and epoxide thermosets. [ABSTRACT FROM AUTHOR]