Method for preparing resin composition for expandable polypropylene carbonate and expandable polypropylene carbonate prepared therefrom

The method of clam 4, wherein the resin composition for an expandable polypropylene carbonate further includes one or a mixture of two or more selected from 0.01 to 50 parts by weight of a flame retardant agent (F) and 1 to 20 parts by weight of an impact reinforcement agent (G).

The method of clam 4, wherein the polypropylene carbonate resin (a1) has a weight average molecular weight of 10,000 to 1,000,000.

The method of clam 4, wherein the thermoplastic resin (a2) is one or a mixture of two or more selected from the group consisting of polyethylene terephthalate glycol (PETG), polylactic acid, polyvinylacetate, polycaprolactone, polymethylmethacrylate, polyethylene-vinylacetate copolymer (EVA), polyethylenemethacrylate glycidylmethacrylate copolymer, polyethylene, polypropylene, polybutylene and copolyester having the following structure.

• (Where, —[R—O]z— represents polyol selected from the group consisting of (a) polyester polyol triol having a molecular weight of 200 to 10,000, (b) polyether glycol having a molecular weight of 200 to 10,000, and (c) polyester polyol diol having a molecular weight of 10,000 or less;
• m represents an integer of 2 to 10, n represents an integer of 0 to 18;
• p represents an integer of 2 to 10, and v, w, x and y each represent an integer of 0 to 100.)