Wholly-degradable poly(propylene carbonate) compound film material and preparation thereof

The invention discloses a completely-degradable poly (propylene carbonate) composite film material and a preparation method thereof. The composite film material is formed by blending and compounding poly (propylene carbonate) with polylactic acid, wherein the content of the polylactic acid is between 10 and 50 weight percent, and the content of the poly (propylene carbonate) is between 50 and 90 weight percent. The preparation method comprises the following steps that: the poly (propylene carbonate) and the polylactic acid are respectively dissolved in organic solvents and made into solutions; the two solutions are well mixed pro rata and volatilized at room temperature so as to eliminate most of the solvents, and then mixed liquid is cast in a plate glass mold; and after the mixed liquid is vacuum-dried to constant mass, a PPC-PLA composite film material can be obtained. The composite film material provided by the invention obviously improves the properties of the poly (propylene carbonate), effectively solves the increasingly serious white pollution problem, and has important significance for ecological environment protection. The preparation method is simple in process, convenient to operate, easy to realize, low in equipment dependence and little in material consumption.