Thermoresistant pla knife/fork/spoon and method for preparing same

A method for preparing a thermoresistant PLA knife/fork/spoon, wherein the method comprises the following steps:

• (1) preparing a knife/fork/spoon preform from a PLA knife/fork/spoon raw material via injection molding using an injection molding machine, the knife/fork/spoon preform comprising PLA that is not completely crystallized;
• and
• (2) subjecting the knife/fork/spoon preform to carbon dioxide soaking treatment at constant temperature and pressure to crystallize the uncrystallized PLA in the knife/fork/spoon preform, so as to obtain a PLA knife/fork/spoon product with a temperature resistance of 65° C. or above;
• wherein, a method of the carbon dioxide soaking treatment in step (2) comprises:
• placing PLA knife/fork/spoon preform in a temperature-adjustable closed container with high temperature and high pressure resistance, injecting the carbon dioxide into the closed container, and soaking at a constant temperature and under retained pressure;
• in step (2), a pressure retaining temperature is 45° C.-110° C., a pressure retaining pressure is 4-12 MPa, a pressure retaining time is 6-60 minutes, and a pressure release speed is 5-45 MPa/s;
• and
• the carbon dioxide is a supercritical carbon dioxide fluid or a subcritical carbon dioxide fluid.