From Linseed Oil to Smart NIPU Polymers: Sustainable, Reprocessable, Self‐Healing Coatings

OpenAlex İngilizce

ABSTRACT In this study, a series of bio‐based, self‐healing non‐isocyanate polyurethane (NIPU) elastomers were synthesized using epoxidized linseed oil, Priamine 1071, disulfide‐containing 4‐APDS, and cyclic carbonated GTGE (CCGTGE). Cyclic carbonate intermediates were successfully obtained and subsequently reacted with various multifunctional amines to generate crosslinked NIPU networks with tunable compositions. The structural and thermal characteristics of the materials were evaluated by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) analyses and dynamic mechanical analysis (DMA). Mechanical properties varied depending on crosslinking density, with higher CCGTGE content leading to increased stiffness and thermal resistance but reduced elasticity. Scanning electron microscope (SEM) imaging supported the observed mechanical trends by revealing differences in fracture surface morphology across formulations. Reprocessability was investigated via hot press cycling, and reprocessing efficiency was calculated based on elongation at break values. Samples containing disulfide linkages demonstrated superior recovery upon reprocessing, underlining the role of dynamic covalent bonds in promoting closed‐loop recyclability. These findings demonstrate a promising approach for designing sustainable, recyclable NIPU‐based coatings.