[Object] To provide a method for producing a vinyl ether polymer containing an oxyethylene chain in a stable and efficient manner, wherein decomposition of the monomer and generation of polyacetal are suppressed.

[Means for solving problem] The method for producing a vinyl ether polymer containing an oxyethylene chain according to the present invention comprises the step of polymerizing vinyl ether represented by the following formula (1):

##STR00001## wherein R.sup.1 represents an alkyl group having 1 to 3 carbons, and n represents an integer from 1 to 10,
in the presence of water as a polymerization solvent, a basic compound as an additive, and an organic azo-based compound as a radical polymerization initiator, and in pH of 5 or more.

A method for producing a hydroxyl group-containing vinyl ether polymer according to the present invention includes: a step of radical polymerizing at least one vinyl ether selected from vinyl ether having a hydroxyl group represented by the following formula (2): ##STR00001## wherein R.sup.7 represents an alkylene group which is straight-chained, branched or comprises an alicyclic structure, and p is 1, 2, or 3, in the presence of water as a polymerization solvent and an azo compound represented by the following formula (1) as a polymerization initiator: ##STR00002## wherein R.sup.1 to R.sup.4 each independently represent a hydrogen atom or an alkyl group and R.sup.5 and R.sup.6 each independently represent an alkoxy group optionally having a substituent group or an alkyl amino group optionally having a substituent group.

A method for producing a hydroxyl group-containing vinyl ether polymer according to the present invention includes: a step of radical polymerizing at least one vinyl ether selected from vinyl ether having a hydroxyl group represented by the following formula (2): ##STR00001## wherein R.sup.7 represents an alkylene group which is straight-chained, branched or comprises an alicyclic structure, and p is 1, 2, or 3, in the presence of water as a polymerization solvent and an azo compound represented by the following formula (1) as a polymerization initiator: ##STR00002## wherein R.sup.1 to R.sup.4 each independently represent a hydrogen atom or an alkyl group and R.sup.5 and R.sup.6 each independently represent an alkoxy group optionally having a substituent group or an alkyl amino group optionally having a substituent group.

The present disclosure relates to compositions that include at least one of

##STR00001##

where each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 includes at least one of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and/or a halogen atom, each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 may be different or the same, and 1z50,000.

The present disclosure relates to compositions that include at least one of

##STR00001##

where each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 includes at least one of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and/or a halogen atom, each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 may be different or the same, and 1z50,000.

A fluoropolymer of a monomer (I) represented by the general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 50% by mass or more based on all polymerization units constituting the fluoropolymer:

CX.sub.2?CXORfSO.sub.3MGeneral formula (I)

wherein X is independently F or CF.sub.3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and M is H, a metal atom, NR.sup.7.sub.4, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R.sup.7 is H or an organic group. Also disclosed are an aqueous solution and coating composition containing the fluoropolymer.

A fluoropolymer of a monomer (I) represented by the general formula (I), wherein a content of a polymerization unit (I) derived from the monomer (I) is 50% by mass or more based on all polymerization units constituting the fluoropolymer:

CX.sub.2?CXORfSO.sub.3MGeneral formula (I)

wherein X is independently F or CF.sub.3; Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and having an ether bond or a keto group; and M is H, a metal atom, NR.sup.7.sub.4, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R.sup.7 is H or an organic group. Also disclosed are an aqueous solution and coating composition containing the fluoropolymer.

The present invention relates to a refrigerator oil containing a polyvinyl ether-based compound (A) containing a structural unit (a1) having a methoxy group in a side chain thereof in an amount of 30 mol % or more and 100 mol % or less on a basis of 100 mol % of the whole amount of structural units excluding a terminal structural unit in a molecular structure thereof, a refrigerator oil composition containing the refrigerator oil, and a production method of the refrigerator oil.

To provide a method for producing a polymer that is capable of providing an alkenyl ether polymer having a molecular weight, a molecular weight distribution, and a composition that are controlled, with a vinyl ether having a hydroxyl group, and a block copolymer thereof. To provide a polymer obtained by the method as a macro chain transfer agent capable of performing reversible addition fragmentation chain transfer polymerization. Livingness can be imparted to radical polymerization of a hydroxyl group-containing vinyl ether by performing the radical polymerization in the presence of a particular RAFT agent and a radical polymerization initiator, and a block copolymer with another radically polymerizable vinyl monomer can be obtained by using the resulting living polymer as a macro chain transfer agent capable of performing reversible addition fragmentation chain transfer polymerization.

To provide a method for producing a polymer that is capable of providing an alkenyl ether polymer having a molecular weight, a molecular weight distribution, and a composition that are controlled, with a vinyl ether having a hydroxyl group, and a block copolymer thereof. To provide a polymer obtained by the method as a macro chain transfer agent capable of performing reversible addition fragmentation chain transfer polymerization. Livingness can be imparted to radical polymerization of a hydroxyl group-containing vinyl ether by performing the radical polymerization in the presence of a particular RAFT agent and a radical polymerization initiator, and a block copolymer with another radically polymerizable vinyl monomer can be obtained by using the resulting living polymer as a macro chain transfer agent capable of performing reversible addition fragmentation chain transfer polymerization.