Multilayer polylactic acid composite plate and preparation method thereof

The invention discloses a multilayer polylactic acid composite plate and a preparation method thereof. The composite plate consists of three layers of structures, wherein the first layer is an anti-impact toughness-enhanced polylactic acid composite layer, the second layer is a high-performance fiber-enhanced polylactic acid composite layer, and the third layer is an anti-impact toughness-enhanced polylactic acid composite layer. The three layers of structures of the composite plate are respectively prepared and are formed after being subjected to hot rolling. The composite plate has the characteristics of high modulus, high intensity and high toughness and biodegradability, and the hardness of the outer layer can be adjusted as required.