Patent ID: 8455591
Filing Date: 2013-06-04
Classification: C08G,C08L

Abstract:
1. A method for producing a polymer polyol (Ia), the method comprising: a first step of polymerizing a monomer-containing mixture liquid (A1) comprising a polyol (a), an ethylenically unsaturated monomer (d), a radical polymerization initiator (k), and a dispersant (e), thereby obtaining a polymer polyol intermediate (B1); and a second step of polymerizing a monomer-containing mixture liquid (Δ2) comprising a polyol (a), an ethylenically unsaturated monomer (d), a radical polymerization initiator (k), a dispersant (e), and a base polymer polyol (h1) that is the intermediate (B1), wherein each of the first step and the second step is a polymerization method in which a mixture for polymerization obtained by mixing (a), (d), and (e), and optionally a diluent (c) is heated to a polymerization temperature, and thereafter the radical polymerization initiator (k) is added to the mixture for polymerization, each concentration of the ethylenically unsaturated monomer (d) in the monomer-containing mixture liquids (A1) and (A2) before the initiation of polymerization in each step is 7 mass % to 25 mass %, a polymer content in the base polymer polyol (h1) is 7 mass % to 25 mass %, a conversion ratio of the ethylenically unsaturated monomer (d) to a polymer in each step is not less than 80 mass %, a conversion rate of the ethylenically unsaturated monomer (d) into a polymer from initiation of the polymerization until the conversion ratio becomes 80 mass % is not less than 8 mass %/min, and a polymer content in a polymer polyol (Ia) obtained finally is 30 mass % to 45 mass %.