Patent ID: 8536238

Claim:
A process for preparing insulation sheets from post-consumer plastic articles, which process comprises: A) providing a plurality of post-consumer plastic articles, said plurality comprising articles made from polyethylene terephthalate, articles made from polystyrene, and optionally articles made from high density polyethylene or other types of plastic; B) crushing said plurality of post-consumer plastic articles to provide a mixture of plastic flakes; C) melt-blending said mixture of plastic flakes, or further reducing the size of particles within said mixture of plastic flakes, to thereby provide a homogeneous mixture of plastic material comprising from about 40 wt % to 100 wt % of a combination of polystyrene (PS) and polyethylene terephthalate (PET) in a PS/PET weight ratio of from about 9:1 to 2:8; and from 0 wt % to about 60 wt % of high density polyethylene; and less than about 5% of other types of plastic; and D) compression molding said homogeneous mixture of plastic material into insulation sheets having a thickness of from about 3 to 10 mm, said insulation sheets exhibiting a thermal conductivity k of from about 0.08 to 0.12 W/m · ° K.