Aqueous polyol dispersion and preparation method thereof and application thereof

An aqueous polyol dispersion, comprising:

• a polycarbonate diol, a non-ionic emulsifier and water;
• wherein, the polycarbonate diol is at least one type of a polycarbonate diol comprising (a), (b), and (c), wherein:
• (a) is a terminal hydroxyl group;
• (b) is a repeating unit represented by formula (1);
• (c) is at least one of a repeating unit represented by formula (2), a repeating unit represented by formula (3) and a repeating unit represented by formula (4);
• in formula (2), n is either 4 or 5;
• in formula (3), m is either 4 or 5;
• in the polycarbonate diol,
• n
• l
• n
• 1
• +
• n
• 2
• +
• n
• 3
• +
• n
• 4
• =
• 25
• -
• 75
• ⁢
• %
• ;
• n
• 2
• n
• 1
• +
• n
• 2
• +
• n
• 3
• +
• n
• 4
• =
• 0
• -
• 75
• ⁢
• %
• ;
• n
• 3
• n
• 1
• +
• n
• 2
• +
• n
• 3
• +
• n
• 4
• =
• 0
• -
• 30
• ⁢
• %
• ;
• ⁢
• n
• 4
• n
• 1
• +
• n
• 2
• +
• n
• 3
• +
• n
• 4
• =
• 0
• -
• 30
• ⁢
• %
• ;
• n1 represents a molar amount of the repeating unit represented by formula (1);
• n2 represents a molar amount of the repeating unit represented by formula (2);
• n3 represents a molar amount of the repeating unit represented by formula (3);
• n4 represents a molar amount of the repeating unit represented by formula (4);
• a weight of the non-ionic emulsifier is 2-20% of a weight of the polycarbonate diol;
• the non-ionic emulsifier is a diblock emulsifier and/or a triblock emulsifier;
• wherein:
• the diblock emulsifier comprises a segment represented by formula (5);
• in formula (5), x and y are integers from 1 to 100, and x/(x+y)=35-85%;
• the triblock emulsifier comprises a segment represented by formula (6);
• in formula (6), x, y and z are integers from 1 to 100, and (x+z)/(x+y+z)=35-85%.