Core‐shell and interpenetrating‐network PU/AC hybrids: synthesis and comparison – waterborne polyurethane/polyacrylate hybrid dispersions

Purpose The purpose of this paper is to synthesise polyurethane/polyacrylate (PU/AC) core‐shell hybrid latex by emulsion polymerisation (PUA) and interpenetrating hybrid latex by soap‐free emulsion polymerisation techniques latex interpenetrating polymer networks (LIPN) and to compare their physico‐chemical and thermo‐mechanical properties. Design/methodology/approach The interactions between the PU and AC components in hybrid coatings were studied with infrared spectroscopy. Mechanical properties were determined by measuring Shore A hardness, pencil hardness and flexibility of dried films. A particle size analyser and scanning electron microscopy were used to investigate the morphology of hybrid resins. Differential scanning calorimetry and thermogravimetric analysis were performed to investigate the thermal stability of polymeric films. Findings The core‐shell hybrids had better physico‐chemical and thermo‐mechanical properties than LIPN hybrids, attributing better interpenetration and entanglement between PU/AC in emulsion polymerisation. Research limitations/implications The syntheses of hybrid polymers can be extended for various combinations of acrylate monomers with crosslinkers, as well as for different types of PU ionomers. Practical implications The comparative study provides a simple and practical solution to improve performance characteristics of PU/AC hybrid coatings, which also proves to be cost effective. Originality/value The findings are of interest to those in surface coatings and adhesive applications.