Bioplastic compositions containing between 2 wt. % and 25 wt. % of at least one starch, between 40 wt. % and 65 wt. % of at least one plasticizer, and between 1 wt. % to 10 wt. % of at least one acid are used as insulation materials. A method of making a bioplastic composition includes the steps of heating a first aqueous mixture containing at least one plasticizer and at least one acid; adding at least one starch to the first aqueous mixture to produce a second aqueous mixture; heating and mixing the second aqueous mixture to produce a precipitate; and separating the precipitate from residual liquid of the second aqueous mixture to produce a bioplastic composition.