In the present study, bio-based cuminaldehyde derived chalcone containing phenol 1-(4-hydroxyphenyl)-3-(4-isopropylphenyl)prop-2-en-1-one (HIP) was synthesized via Claisen-Schmidt condensation using a bio-derived aldehyde and p-hydroxyacetophenone. The structure of the synthesized HIP was confirmed through attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR), and high-resolution mass spectrometry (HRMS). A series of chalcone based benzoxazine monomers was subsequently synthesized through the Mannich condensation reaction and designated as CM-AN, CM-ODA, CM-DDA, and CM-FFA. ATR-FTIR, 1H NMR and 2D COSY 1H–1H NMR spectral techniques were employed to confirm the structure of monomer, while X-ray photoelectron spectroscopy (XPS) and solid-state 13C NMR analyses were performed to characterize the structure of poly(CM-FFA). Thermal behavior of the monomers was evaluated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The curing temperatures of the benzoxazines were found to be 173°C, 194°C, 223°C, and 216°C, respectively. The maximum degradation temperatures of the synthesized polymers were ranged between 422 and 452°C, respectively. Among the polymers, poly(CM-FFA) exhibited the highest initial and maximum degradation thermal stability. Optical properties were assessed using UV-Vis spectroscopy, which confirms the photoisomerization of the chalcone moiety and also revealing the band gap energies of 3.47 eV, 3.36 eV, 3.46 eV, and 3.44 eV through Tauc plot for the synthesized polymers. Hydrophobic characteristics were evaluated through water contact angle measurements, poly(CM-ODA) exhibiting the highest contact angle, indicating superior surface hydrophobicity. The durability of the polybenzoxazine coated fabric was assessed by subjecting it to multiple n-hexane washing cycles and exposing it to different pH solutions. In addition to that, analysis such as density functional theory (DFT), the antimicrobial activity, Minimum Inhibitory Concentration (MIC) assessment, coating stability tests, Taber abrasion resistance and corrosion inhibition efficiency were also performed. The results revealed that the synthesized polymer is applicable for coating applications in different environmental conditions. Swell tests were also performed to determine the crosslinking efficiency of the developed