Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE UV-curable polyurethane acrylate (PUA) resins were prepared using isophorone diisocyanate (IPDI) and polyhydric alcohols as structural units. The water washability crosslinking density of the PUA resins was improved simultaneously.


ABSTRACT
Series water washable and UV-curable polyurethane acrylate (PUA) resins were prepared using isophorone diisocyanate (IPDI) and polyhydric alcohols as structural units. The structures of PUA resins with different types of polyols, different R values (NCO/OH ratios), and molecular weights were well characterized. Physical properties, water contact angle, and washability of PUA resins were examined. Mechanical properties, thermal stability, and curing shrinkage properties of PUA resins after photopolymerization were also investigated. The optimized formulation (IPDI-PPG-1000-2.5) (PPG: polypropylene glycol) exhibited its superior properties such as mechanical properties, thermal stability, water washable properties, and curing shrinkage rate with a Young's modulus of 325.20 MPa, a tensile strength of 7.25 MPa, and a temperature of 224.5°C at a mass loss of 5%, respectively. This PUA resin is capable of producing 3D physical entities via photopolymerization with smooth surfaces and clearly defined shapes. Also, no sticky touch on the surface was obtained after washing with water. This work provides an innovative strategy to prepare high-performance water washable PUA resin that could be applied in 3D printing.