Patent ID: 8106104

Claim:
A method for preparing a reformulated plastic-containing feed material wherein the reformulated plastic-containing feed material is blended from a plurality of batches of contaminated, reclaimed mixed waste plastic comprising gross contaminants, filler materials, and a major portion of linear short chain branched polyethylene (LSCBPE), the method comprising: preprocessing a plurality of different batches of contaminated, reclaimed mixed waste plastic by removing the gross contaminants, shredding the resultant product, densifying the shredded mixed waste plastic to a bulk density of at least about 16 pounds per cubic foot, and pulverizing the densified mixed waste plastic to a predetermined maximum particle size; selecting a sample from each of the plurality of batches of preprocessed mixed waste plastic; further reducing the particle size of the sample to obtain a more uniform particle size distribution; injection molding a substantially homogeneous composition from the mixed waste plastic within each sample; analyzing at least a portion of each injection molded composition to determine from a graph of the heat of melting versus temperature the heat flux required to melt the LSCBPE in the analyzed portion of the injection molded composition; calculating the LSCBPE content of the sample; calculating a reformulated blend including mixed waste plastic from at least some of the plurality of batches of mixed waste plastic based upon the LSCBPE content of the injection molded compositions; and blending a quantity of mixed waste plastic from the at least some of the plurality of batches of mixed waste plastic according to the calculated reformulated blend to produce a reformulated plastic-containing feed material having a desired LSCBPE content.