摘要 |
Disclosed is a method for producing a photocurable liquid resin characterized by comprising a step (A) wherein a conjugated diene polymer or conjugated diene/aromatic vinyl copolymer having a weight average molecular weight of 5,000-40,000 and a molecular weight distribution of not more than 3.0 is produced by polymerizing a conjugated diene monomer or a conjugated diene monomer and an aromatic vinyl monomer in a saturated hydrocarbon solvent using a dilithium initiator; a step (B) wherein a conjugated diene polymer based polyol or conjugated diene/aromatic vinyl copolymer based polyol is produced by reacting the conjugated diene polymer or conjugated diene/aromatic vinyl copolymer with an alkylene oxide; a step (C) wherein a hydrogenated conjugated diene polymer based polyol or hydrogenated conjugated diene/aromatic vinyl copolymer based polyol is produced by hydrogenating the conjugated diene polymer based polyol or conjugated diene/aromatic vinyl copolymer based polyol; and a step (D) wherein the hydrogenated conjugated diene polymer based polyol or hydrogenated conjugated diene/aromatic vinyl copolymer based polyol is reacted with a photocurable unsaturated hydrocarbon group-containing compound. Since the photocurable liquid resin has high water vapor barrier properties and excellent heat resistance while having adequate hardness as a rubber elastic material, it is suitable for sealing materials.
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