Copolymer for separator, and secondary battery comprising same
The present disclosure relates to a copolymer, which contains: an acrylonitrile-based monomer unit in an amount in a range of greater than 0 wt % and 15 wt % or less; a hydroxyl group (—OH)-containing acrylate-based monomer unit in an amount in a range of greater than 0 wt % and 5 wt % or less; an acrylamide-based monomer unit in an amount in a range of greater than 80 wt % and less than 95 wt %; and an acrylic acid-based monomer unit in an amount in a range of greater than 0 wt % and 15 wt % or less, based on the total weight of the copolymer in an amount of 100 wt %, to a slurry composition containing the copolymer, to a separator, and to a secondary battery.
1 . A copolymer comprising:
an acrylonitrile-based monomer unit in an amount in a range of greater than 0 wt % and 15 wt % or less;
a hydroxyl group (—OH)-containing acrylate-based monomer unit in an amount in a range of greater than 0 wt % and 5 wt % or less;
an acrylamide-based monomer unit in an amount in a range of greater than 80 wt % and less than 95 wt %; and
an acrylic acid-based monomer unit in an amount in a range of greater than 0 wt % and 15 wt % or less, based on the total weight of the copolymer in an amount of 100 wt % %,
wherein an alkali metal is bound to a carboxylate group of at least one acrylic acid-based monomer unit,
wherein a secondary amine, a tertiary amine, or a combination thereof is bound to a carboxylate group of at least one acrylic acid-based monomer unit.
2 . The copolymer of claim 1 , wherein the copolymer is represented by Formula 1,
wherein in Formula 1,
R 1 to R 3 are each independently hydrogen, or a straight-chain or branched-chain hydrocarbon having 1 to 4 carbon atoms,
M comprises an alkali metal and at least one selected from the group consisting of a secondary amine and a tertiary amine,
n is an integer in a range of 0 to 500, and
m, l, x, and y satisfy m+l+x+y=1.
3 . The copolymer of claim 2 , wherein R 1 to R 3 in Formula 1 each independently comprise at least one selected from the group consisting of hydrogen, methyl, and ethyl.
4 . The copolymer of claim 2 , wherein M in Formula 1 comprises at least one selected from the group consisting of compounds represented by Formulas 2 to 5,
wherein in Formulas 2 and 3,
R 4 to R 6 are each independently a straight-chain or branched-chain hydrocarbon having 1 to 6 carbon atoms, and
wherein Formulas 4 and 5,
L 1 to L 3 are each independently an alkylene group having 1 to 6 carbon atoms, and
a to c are each independently an integer in a range of 0 to 2.
5 . The copolymer of claim 1 , wherein the copolymer is a random or block copolymer.
6 . The copolymer of claim 1 , wherein the copolymer has a number average molecular weight in a range of 5,000 to 1,000,000.
7 . A slurry composition comprising:
the copolymer of claim 1 ; and
inorganic particles.
8 . A separator comprising the slurry composition of claim 7 .