Graft polymer composition and its production process and uses

A production process for a graft polymer composition, which comprises the step of adding a monoethylenically unsaturated monomer component to a mixture of at least two polyether compounds in order to graft-polymerize the monoethylenically unsaturated monomer component at the same time onto the at least two polyether compounds, wherein the monoethylenically unsaturated monomer component includes an unsaturated carboxylic monomer as an essential component;

• wherein there is a difference of not less than 3 in number of carbon atoms in the end structural unit when the number of carbon atoms which compose each structural unit located at both ends is compared between the at least two polyether compounds under the following conditions (i) and (ii) where:
• (i) a portion ranging from an extremely located ether bond portion to an end is defined as the end structural unit, and when there is a difference in number of carbon atoms between both end structural units of each polyether compound, whichever is larger is defined as the number of carbon atoms in the end structural unit;
• and
• (ii) when an end is a structural unit derived from an alkylene oxide, the number of carbon atoms in this end structural unit is defined as zero.

A production process for a graft polymer composition, which comprises the step of blending graft polymers (A) and (A′) together, wherein:

• the graft polymer (A) is obtained by graft-polymerizing a monoethylenically unsaturated monomer component onto a polyether compound (a), wherein the monoethylenically unsaturated monomer component includes an unsaturated carboxylic monomer as an essential component;
• and
• the graft polymer (A′) is obtained by graft-polymerizing a monoethylenically unsaturated monomer component onto a polyether compound (a′), wherein the monoethylenically unsaturated monomer component includes an unsaturated carboxylic monomer as an essential component;
• wherein there is a difference of not less than 3 in number of carbon atoms in the end structural unit when the number of carbon atoms which compose each structural unit located at both ends is compared between the polyether compounds (a) and (a′) under the following conditions (i) and (ii) where:
• (i) a portion ranging from an extremely located ether bond portion to an end is defined as the end structural unit, and when there is a difference in number of carbon atoms between both end structural units of each polyether compound, whichever is larger is defined as the number of carbon atoms in the end structural unit;
• and
• (ii) when an end is a structural unit derived from an alkylene oxide, the number of carbon atoms in this end structural unit is defined as zero.