Fine Particle-Dispersed Polyol Composition, Method for Producing Polymer Polyol, and Method for Producing Polyurethane Resin

Abstract

A polyol composition comprising a polyol (a) and resin fine particles (b) dispersed in the polyol (a), and a method for producing the polyol composition are provided, wherein the resin fine particles (b) are particles such that an arithmetic standard deviation by volume of a particle size distribution of the particles, derived from respective values in 85 divisions of a range of 0.020 to 2000 μm determined by a laser diffraction/scattering particle size distribution analyzer, is not more than 0.6. A resin fine particle-dispersed polyol composition that, even if the resin particles dispersed in the polyol have a small particle diameter, allows the production of a polyurethane resin having an excellent mechanical strength such as elongation at break, and a method for producing the same, are provided.

1 . A polyol composition (I) comprising a polyol (a) and resin fine particles (b) dispersed in the polyol (a), wherein the resin fine particles (b) are particles such that an arithmetic standard deviation by volume of a particle size distribution of the particles, derived from respective values in 85 divisions of a range of 0.020 to 2000 μm determined by a laser diffraction/scattering particle size distribution analyzer, is not more than 0.6. 
   
   
       2 . The polyol composition (I) according to  claim 1 , wherein the resin fine particles (b) satisfy the following formula (I):
   [ P]/[Q]≧ 1.7 ×[R]   0.93   (1)   
     where [R] represents an arithmetic average particle diameter (μm), [P] represents a mode value (by volume: %), and [Q] represents a difference (μm) between the largest particle diameter and the smallest particle diameter. 
   
   
       3 . The polyol composition (I) according to  claim 1 , wherein an arithmetic average particle diameter [R] of the resin fine particles (b) is 0.3 μm to 3.0 μm. 
   
   
       4 . The polyol composition (I) according to  claim 1 , wherein a content of particles having a diameter of not less than 10 μm in the resin fine particles (b) is not more than 2 vol %. 
   
   
       5 . The polyol composition (I) according to  claim 1 , wherein a content of the resin fine particles (b) in the polyol composition (I) is 35 mass % to 65 mass %. 
   
   
       6 . The polyol composition (I) according to  claim 1 , wherein the resin fine particles (b) are polymer particles formed by polymerization of an ethylenically unsaturated monomer (d). 
   
   
       7 . The polyol composition (I) according to  claim 6 , formed by polymerization of the ethylenically unsaturated monomer (d) in the polyol (a) with a diluent (c) as required, in the presence of a radical polymerization initiator (k), in the presence or absence of a dispersant (e). 
   
   
       8 . The polyol composition (I) according to  claim 7 , formed by polymerization in the presence of the dispersant (e), the dispersant (e) being 1 mass % to 50 mass % based on the mass of the ethylenically unsaturated monomer (d). 
   
   
       9 . The polyol composition (I) according to  claim 7 , formed by polymerization in the presence of the diluent (c) having a solubility parameter (SP value) of 7 to 11, the diluent (c) being 1 mass % to 15 mass % based on the mass of the polyol composition (I). 
   
   
       10 . The polyol composition (I) according to any one of  claim 6 , wherein the monomer (d) comprises not more than 98 mass % of styrene, and 2 mass % to 15 mass % of α-alkenyl-group-containing alkylene oxide adduct. 
   
   
       11 . The polyol composition (I) according to  claim 6 , formed by a one-step polymerization method carried out by adding a radical polymerization initiator (k) into a mixture at a polymerization temperature comprising the polyol (a), the ethylenically unsaturated monomer (d), and a dispersant (e), as well as a diluent (c) as required. 
   
   
       12 . A method for producing a polyurethane resin by causing a polyol component and an organic polyisocyanate to react, in the presence of one or more selected from a catalyst, a blowing agent, and a foam stabilizer as required, wherein the polyol composition (I) according to any one of  claim 1  is used as at least a part of the polyol component. 
   
   
       13 . 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 (A2) 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 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 %.   
   
   
       14 . 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   an (i+1)th step of polymerizing a monomer-containing mixture liquid (Ai+1) comprising a polyol (a), an ethylenically unsaturated monomer (d), a radical polymerization initiator (k), a dispersant (e), and a base polymer polyol (hi) that is an intermediate (Bi), thereby obtaining a polymer polyol intermediate (Bi+1), where i is an integer incremented from 1 to n−1 whereby this step is repeated n−1 times, wherein the polymer polyol intermediate (Bi+1) is to be used as a base polymer polyol (hi+1) in a next step whereby the ethylenically unsaturated monomer (d) is polymerized likewise,   wherein   the total number n of repetition times is 3 to 7,   each concentration of the ethylenically unsaturated monomer (d) in the monomer-containing mixture liquids (A1) and (Ai+1) before the initiation of polymerization in each step is 7 mass % to 25 mass %,   a polymer content in the base polymer polyol (hi) is 7 mass % to 50 mass %, and   a polymer content in a polymer polyol (Ia) obtained finally is 30 mass % to 65 mass %.   
   
   
       15 . The method according to  claim 14 , wherein
 a conversion ratio of the ethylenically unsaturated monomer (d) to a polymer in each step is not less than 80 mass %, and   a conversion rate of the ethylenically unsaturated monomer (d) into a polymer from initiation of the polymerization until the conversion ratio becomes 80 mass % in each step is not less than 8 mass %/min.   
   
   
       16 . The method according to  claim 13 , wherein in a particle size distribution by volume of polymer particles in the polymer polyol (Ia), derived from respective values in 85 divisions of a range of 0.020 to 2000 μm determined by a laser diffraction/scattering particle size distribution analyzer, a content of particles having a diameter of not less than 10 μm in the polymer particles is not more than 2 vol %. 
   
   
       17 . The method according to  claim 13 , wherein in a particle size distribution of the polymer particles in the polymer polyol (Ia), derived from respective values in 85 divisions of a range of 0.020 to 2000 μm determined by a laser diffraction/scattering particle size distribution analyzer, an arithmetic standard deviation by volume of the polymer particles is not more than 0.6. 
   
   
       18 . The method according to  claim 13 , wherein a content of polyoxyalkylene ether in α-alkyenyl-group-containing compound in the ethylenically unsaturated monomer (d) is 2 mass % to 15 mass %. 
   
   
       19 . A method for producing a polyurethane resin, comprising the step of causing a polyol component and a polyisocyanate component to react, in the presence of one or more additives selected from a catalyst, a blowing agent, and a foam stabilizer as required, wherein the polymer polyol (Ia) obtained by the method according to  claim 13  is used as at least a part of the polyol component.