The present work provides a facile process route for the syntheses of pyrimidinone‐based benzoxazines by using stoichiometric quantities of pyrimidinone bisphenol (PBU) and paraformaldehyde, which are separately reacted with various types of amines under suitable experimental conditions. The molecular structure, curing characteristics, thermostability, hydrophobic behavior, and dielectric properties were analyzed using appropriate analytical methods. The polymerization temperature (Tp) of monomers such as PBU‐oda, PBU‐cha, PBU‐ffa, PBU‐a, and PBU‐fa was determined by differential scanning calorimetry (DSC), and the Tp values were noted at 205, 198, 203, 218, and 240°C, respectively. The percentage carbon residue at 850°C for poly(PBU‐oda), poly(PBU‐cha), poly(PBU‐ffa), poly(PBU‐a), and poly(PBU‐fa) were analyzed using thermogravimetric analysis (TGA). The water interface angle values for poly(PBU‐oda), poly(PBU‐cha), poly(PBU‐ffa), poly(PBU‐a), and poly(PBU‐fa) was found to be 141°, 134°, 142°, 136°, and 142°, respectively. The results from the dielectric studies indicate that the benzoxazines (PBU‐ffa and PBU‐a) composites reinforced with palm flower silica (PF‐SiO2) and boron nitride‐g‐C3N4 (BN‐g‐C3N4) were found to be suitable for low and high dielectric applications. From these diverse studies, it can be determined that pyrimidinone‐based benzoxazines to be utilized as high‐performance products in the form of encapsulants, potting agents, and composites for automotive and microprocessor applications.Highlights Pyrimidinone core bisphenol has developed through the efficient method. New pyrimidinone core bisphenol based benzoxazine resins have been developed. BN‐g‐C3N4 filled polybenzoxazine composites have prepared for high‐k applications. Palm flower ash filled polybenzoxazine composites have prepared low‐k applications. Thermal and morphological behavior of composites were studied.

: Plant extracts contain secondary metabolites which have the potential to act as reducing and stabilizing agents contributing to a greener and more efficient method to synthesize nanoparticles. Rapid growth of Nanotechnology has led to an increased demand in various fields. This review summarizes the use of potent medicinal plant extracts to synthesize metal nanoparticles, methods employed to characterize the properties of the nanoparticles and its application. Characterization of the nanoparticle based on its shape, size, chemical bonds, surface properties, hydrodynamic diameter and crystalline structure using techniques such as UV-Visible Spectroscopy, XRD (X-Ray Diffraction), TEM (Transmission Electron Microscopy), SEM (Scanning Electron Microscopy), EDS (X-ray energy dispersive spectroscopy), DLS (Dynamic Light Scattering), Zeta Potential and FTIR (Fourier Transform-Infrared Spectroscopy) are elaborated. The synthesized metal nanoparticles have wide ranges of applications such as the antimicrobial activity, antioxidative capability, anticancer effect, anti-diabetic properties, plant growth enhancement, dye degradation effects and anti-larval properties. Recent advances in nanotechnology with special emphasis to plant metabolites provide an insight about their usage as plant-derived edible nanoparticles (PDNPs). Applications, limitations and future prospects of this technology have also been briefly discussed.