The use of non-degradable plastic mulch film causes significant environmental pollution and poses a threat to human and ecological safety. To address this issue, a viable solution is to develop bio-based and biodegradable paper mulch films to replace non-biodegradable ones in agricultural soils. In this study, a green and straightforward process was used to synthesize lignin-based polyurethane (LPU), which was then coated on cellulose paper (CP) of low basis weight of 30 g/m to fabricate a composite LPU/CP mulch film. An ultra-thin and lightweight LPU/CP mulch film was successfully fabricated with basis weight, thickness, and specific density of 40 g/m, 80 µm, and 0.5 g/cm, respectively. It was observed that surface coating was very effective in improving the physical strength of composite film as indicated by the improvement of tensile index from 19.3 N·m/g of CP to 65.0 N·m/g of LPU/CP mulch film. Moreover, LPU/CP mulch film presented excellent water resistance properties as suggested by the water contact angle of 107° and the water vapor transmission rate of 639.3 g/m·day. LPU/CP mulch film also shows a balance between degradability and durability that it starts to break down into fractions after being buried for 28 days as a result of microbiological degradation. This work provides a feasible technology for fabricating eco-friendly, cost-effective, and biodegradable paper mulch film.

中文翻译：

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木质素基聚氨酯（LPU）的合成及其在纤维素纸上涂覆LPU制备可降解地膜


不可降解塑料地膜的使用造成严重的环境污染，对人类和生态安全构成威胁。为了解决这个问题，一个可行的解决方案是开发生物基和可生物降解的纸地膜来替代农业土壤中的不可生物降解的地膜。在这项研究中，采用绿色、简单的工艺合成木质素基聚氨酯（LPU），然后将其涂覆在低定量30克/平方米的纤维素纸（CP）上以制造复合LPU/CP地膜。成功制备了超薄轻质 LPU/CP 地膜，基重、厚度和比重分别为 40 g/m、80 µm 和 0.5 g/cm。结果表明，表面涂层对于提高复合膜的物理强度非常有效，拉伸指数从 CP 的 19.3 N·m/g 提高到 LPU/CP 地膜的 65.0 N·m/g。此外，LPU/CP 地膜表现出优异的耐水性能，水接触角为 107°，水蒸气透过率为 639.3 g/m·day。 LPU/CP地膜还表现出可降解性和耐久性之间的平衡，在埋藏28天后，由于微生物降解，它开始分解成碎片。这项工作为制造环保、经济、可生物降解的纸质地膜提供了一种可行的技术。