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With the increasing demand for range of new energy vehicles, in addition to improving the energy density and enlarging the size of the power battery, lightweighting the body structure is also an important method to improve the range of new energy vehicles. Due to their lower density and stronger strength compared to metals, fiberglass composite materials and carbon fiber composite materials are becoming increasingly widely used in new energy vehicle applications. Polyurethane resin is a polymer material that combines toughness and strength. Its performance advantages over epoxy and other resin systems in composite materials are gradually replacing other materials and becoming an important polymer material used in composite materials.