Preparation castor oil-modified high bio-based waterborne polyurethane and its application

At present, the research hotspot of polyurethane synthesis focuses on developing bio-based materials with ecological and excellent performance. This paper synthesized a series of castor oil-modified bio-based waterborne polyurethanes (CWBPU) by adjusting the castor oil (CO) content. We used 1,5-pentamethylene diisocyanate and bio-based polyether polyols as base materials. CWBPU had the advantages of environmental protection and degradability, and the bio-based content was as high as 82%. Results showed that, with the increase of CO content from 0% to 8.97%, the tensile strength increased from 3.85 MPa to 8.86 MPa, and the elongation at break gradually decreased from 496.2% to 356.6%. The water contact angle of the films increased by about 30°, and the water absorption rate dropped from 17.44% to 7.6%. Compared with the uncoated leatherette paper, the longitudinal tear strength of the coated flush cover paper was twice that of the base paper, and the transverse tensile strength and burst resistance significantly enhanced.