Allophanate group-containing polyisocyanate composition, polyurethane resin-forming composition, seal material, membrane module
An allophanate group-containing polyisocyanate composition that contributes to the formation of a polyurethane resin with fewer bubbles is provided. Disclosed is an allophanate group-containing polyisocyanate composition (C) including a reaction product of diphenylmethane diisocyanate (A) and a hydroxyl group-containing compound (B), wherein the hydroxyl group-containing compound (B) includes a hydroxyl group-containing polymethylsiloxane compound (B-1) in an amount of 1 ppm or more and 300 ppm or less.
1. An allophanate group-containing polyisocyanate composition (C) comprising a reaction product of diphenylmethane diisocyanate (A) and a hydroxyl group-containing compound (B),
wherein the reaction product includes an allophanate group,
the hydroxyl group-containing compound (B) includes a hydroxyl group-containing polymethylsiloxane compound (B-1) and a monool compound (B-2) having a molecular weight of 2,000 or less, and
a content of the hydroxyl group-containing polymethylsiloxane compound (B-1) in the reaction mixture is 1 ppm or more and 300 ppm or less with respect to a total amount of the diphenylmethane diisocyanate (A) and the hydroxyl group-containing compound (B), and
a content of the monool compound (B-2) in the reaction mixture is 19.2 mass % or more and 32.0 mass % or less with respect to a total amount of the diphenylmethane diisocyanate (A) and the hydroxyl group-containing compound (B).
2. The allophanate group-containing polyisocyanate composition (C) according to claim 1 , wherein the content of the hydroxyl group-containing polymethylsiloxane compound (B-1) is 1 ppm or more and 200 ppm or less.
3. The allophanate group-containing polyisocyanate composition (C) according to claim 1 , wherein the content of the hydroxyl group-containing polymethylsiloxane compound (B-1) is 1 ppm or more and 100 ppm or less.
4. A polyurethane resin-forming composition comprising the allophanate group-containing polyisocyanate composition (C) according to claim 1 and a polyol component (D).
5. A seal material comprising a cured product of the polyurethane resin-forming composition according to claim 4 .
6. A membrane module comprising:
a main body unit;
a membrane; and
a seal material sealing gaps between the main body unit and the membrane,
wherein the seal material is the seal material according to claim 5 .
7. The membrane module according to claim 6 ,
wherein the membrane is a plurality of lines of hollow fiber membranes, and
the seal material seals the gaps between the main body unit and at least a portion of the plurality of lines of hollow fiber membranes, and at least a portion of mutual gaps between the plurality of lines of hollow fiber membranes.