Isocyanate-modified rigid thermoplastic polymer compositions

A method for making a thermoplastic polymer comprising:

• combining at least one polymeric polyester diol, at least one monomeric diisocyanate, and, optionally, at least one supplemental monomeric diol in a reaction zone, optionally, in the presence of a catalyst;
• and
• reacting the combination in the reaction zone to form a thermoplastic polymer;
• wherein the thermoplastic polymer comprises:
• (a) residues of the at least one linear polymeric polyester diol, wherein said linear polymeric polyester diol comprises residues of—
• (i) at least one monomeric diacid;
• and
• (ii) at least one monomeric diol,
• wherein said linear polymeric polyester diol has a number average molecular weight of at least 400 Daltons;
• and
• (b) residues of the at least one diisocyanate monomer, wherein said residues of said diisocyanate monomer are present in said polymer in an amount of not more than 40 weight percent, based on the total weight of said polymer, and
• wherein said polymer has a tensile modulus of at least 1000 MPa.