Molecular Plant Breeding 2024, Vol.15, No.1, 34-41 http://genbreedpublisher.com/index.php/mpb 36 Figure 1 Starch structural formula (Adopted from Vamadevan and Bertoft, 2015) Image caption: (a) straight chain starch; (b) branched chain starch (Adopted from Vamadevan and Bertoft, 2015) 2.2 Cellulose Cellulose is one of the most abundant naturally occurring organic polymers and is a naturally occurring polysaccharide of D-glucose linked by β-1,4-glycosidic bonds (Praveen et al., 2019). Like starch, cellulose molecules have strong hydrogen bonding between them, are highly crystalline (Xue et al., 2022), and are insoluble in common solvents (Solberg et al., 2023), which makes it difficult to be plasticized and film-forming (Figure 2). Therefore, it is necessary to modify or blend cellulosic mulch materials in the preparation of cellulosic mulch materials (Liu et al., 2008). Early on, fully degradable agricultural films were produced from bagasse pulp as the main raw material, with a small amount of cotton pulp and starch (Qin et al., 2002). In recent years, the production of cellulosic composites and the related property verification experiments are increasing (Saberi, 2024). For example, jute/cotton mulch is based on cotton stalk fibers and waste cotton fibers as the main raw material, and its decomposition in the soil increases the nitrogen content of the soil and has better water infiltration, which can meet the requirements of agricultural production (Wang et al., 2018). Figure 2 Molecular structural formula of cellulose (Adopted from Heinze, 2016) 2.3PLA PLA is a linear macromolecule polymerized from small-molecule lactic acid produced by microbial fermentation of biomass raw materials (sugarcane, sugar beet, straw cellulose, cassava, etc.) and belongs to the class of poly (α-hydroxy ester) (Balla et al., 2021) (Figure 3). PLA is not only degradable and biocompatible, but also can be produced and processed using most common processing equipment, but its own brittleness will bring many defects to its membranes (Hayes et al., 2012). PLA-based biodegradable membranes need to be modified or blended when preparing them (Noda et al., 2004). For example, the use of Al layered dihydroxide in stearate-Mg3PLA films greatly improved the elongation at break (Mahboobeh et al., 2010); Muller et al. (2017) attempted to prepare a bilayered composite ground film by blending PLA with starch and examined the barrier, tensile, and optical properties of the composite film. The results showed that the composite ground film not only
RkJQdWJsaXNoZXIy MjQ4ODYzMg==