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.

目前聚氨酯合成的研究热点集中在开发生态性能优良的生物基材料。本文通过调节蓖麻油（CO）含量合成了一系列蓖麻油改性生物基水性聚氨酯（CWBPU）。我们使用 1,5-五亚甲基二异氰酸酯和生物基聚醚多元醇作为基础材料。CWBPU具有环保、可降解等优点，生物基含量高达82%。结果表明，随着CO含量从0%增加到8.97%，拉伸强度从3.85 MPa增加到8.86 MPa，断裂伸长率从496.2%逐渐降低到356.6%。薄膜的水接触角增加了约30°，吸水率从17.44%下降到7.6%。与无涂层的人造革纸相比，