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The preparation of biodegradable polyurethane materials takes advantage of the high reactivity of the isocyanate groups in polyisocyanate components, as well as the biodegradability of natural polymers. In theory, natural polymers containing multiple hydroxyl groups can be used as one of the polyol components; through the reaction between these polyol components and the polyisocyanate components, molecular chains that can be broken down by microorganisms can be incorporated into the polyurethane material. When treated by the soil burial method, the material undergoes reactions such as hydrolysis and oxidation under the action of microbial enzymes; these molecular chains break down into fragments with lower relative molecular masses. After microorganisms absorb or consume these low-molecular-weight fragments, they convert them through metabolism into carbon dioxide, water, and biological energy, thereby achieving degradation. Due to the sensitivity of polyurethanes to common microorganisms, they are an ideal material for producing biodegradable materials; moreover, their structure can be designed freely. As a result, there are currently many types of biodegradable polyurethanes under investigation, including polyether-type and polyester-type polyurethanes, as well as polyurethanes modified with natural biodegradable polymers. Polyethers used in the synthesis of polyether polyurethanes include polyoxyethylene (PEO), polytetramethylether (PTMO), polypropylene oxide (PPO), and others. Compared to polyether-type ones, polyester-type polyurethanes are more prone to degradation, mainly because polyesters are easily hydrolyzed in living organisms. Commonly used polyesters include PCL, PLA, PGA, and their copolymers such as lactide/glycolic acid copolymer (PLGA), etc. Numerous studies have shown that these polyester soft segments also possess excellent biodegradability, allowing them to be safely degraded within living organisms. YOUNGDUKKIM et al. synthesized several polyester-based polyurethanes with different chemical structures, and investigated their biodegradability through hydrolysis, enzymatic degradation, and landfilling. Studies have found that polyurethanes synthesized using aliphatic diisocyanates and polyester polyols with numerous soft chain segments exhibit good biodegradability.