Degradable Polyvinyl Alcohol Liquid Mulch Film Synergistically Reinforced by Cellulose and Lignin

Degradable polyvinyl alcohol (PVA) liquid mulch film is an effective alternative to traditional petroleum-based mulch. However, PVA has problems such as poor water resistance and high cost in practical applications. In this work, a liquid mulch film PCQ was prepared by simply blending quaternized lignin (QAL), carboxymethyl cellulose (CMC), and PVA. PCQ was characterized and analyzed through FT-IR, SEM, and other tests. The effects of QAL and CMC on the water resistance, barrier properties, water retention, soil-fixing properties, and degradation properties of PCQ were investigated. The results showed that the addition of QAL and CMC significantly enhanced the water resistance of the liquid mulch film and provided excellent UV shielding (90%) and water vapor shielding performance (249.3 g m-2 d-1). In addition, PCQ effectively immobilized topsoil, retained soil moisture, and improved seed germination. This study provides a new strategy for preparing environmentally friendly, low-cost, and degradable liquid mulch film.