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Chiral polyureas of cinchona alkaloids were synthesized via repetitive Mizoroki‐Heck (MH) coupling reaction. The Pd‐catalyzed polycondensation of cinchona urea dimers 6 and aromatic diiodide 7 afforded the chiral polyureas (P1−P4). The catalytic activity of the chiral polymers was subsequently investigated. The asymmetric Michael addition of ketoesters to nitroolefins was successfully catalyzed by the polymeric organocatalysts (P1−P4) to give the corresponding Michael adducts with high catalytic activities and excellent enantionselectivities (up to >99% ee). The polymeric catalysts were insoluble in commonly used organic solvents. They were easily recovered and reused several times without any loss of the catalytic activity.

Waste date palm fiber (DPF) has recently emerged as a promising natural fiber due to its abundance, renewability, and low cost. The study discussed the use of DPF as reinforcement in composites, particularly in polybenzoxazine (PBz), epoxy resin (EP), and their copolymer (EP‐co‐PBz) composites. The waste DPF underwent an alkaline treatment process, resulting in a high‐performance material that exhibits exceptional interaction with the matrix. The composite samples were fabricated using 5–20 wt% of alkali treated DPFs with polybenzoxazines and epoxy resins. The study examined the thermal and morphological properties of the resulting composites and found that they exhibited remarkable enhancements in various properties. For instance, the PNaphz‐COOH reinforced 5 wt% DPFs composite showed a significant increase in Td5% and Td10%, while the EP‐co‐PBz reinforced DPFs composites exhibited a remarkable increase in char yield (Yc). The SEM analysis of the composite surface further validated these findings, highlighting the remarkable interfacial bonding between the DPFs and the matrix. The remarkable enhancements in thermal properties demonstrated in this study open up new possibilities for utilizing waste DPF in various applications.Highlights Waste date palm fiber enhances thermosetting polymer reinforcement for high‐performance composites. Alkaline treatment improves interfacial bonding between waste DPF and matrix. Composites reinforced with waste DPF exhibit outstanding thermal and morphological properties.