A polymer substrate, such as a polymer particle, is formed from a carboxyl functional monomer. In an example, the carboxyl functional monomer has a protection group in place of the OH of the carboxyl group. Once the monomer is polymerized, such a protection group can be removed, providing a polymer network with carboxyl functional sites. Such sites can be used to attach other functionality to the polymer substrate.

A polymer substrate, such as a polymer particle, is formed from a carboxyl functional monomer. In an example, the carboxyl functional monomer has a protection group in place of the OH of the carboxyl group. Once the monomer is polymerized, such a protection group can be removed, providing a polymer network with carboxyl functional sites. Such sites can be used to attach other functionality to the polymer substrate.

The invention relates to acrylonitrile-based cation exchangers, to a process for the production thereof and to the use thereof for decationization and/or softening of aqueous or organic solutions.

The invention relates to acrylonitrile-based cation exchangers, to a process for the production thereof and to the use thereof for decationization and/or softening of aqueous or organic solutions.

To provide an optical product including an anti-fog coating film having excellent anti-fog durability. An optical product including a transparent material and an anti-fog coating film disposed on a surface of the transparent material, in which the anti-fog coating film is obtained by drying and/or curing a coating film formed from an anti-fog coating composition, the anti-fog coating composition contains a polymer (A), a substrate component (B), and a surfactant (C), the polymer (A) includes a constituent unit derived from a compound (a) having an ethylenically unsaturated group and an ionic group, a constituent unit derived from a compound (b) having an ethylenically unsaturated group and an OH group and/or an NH.sub.2 group, and a constituent unit derived from a compound (c) represented by the following formula (c-1), and has a structure derived from a compound (d) having a thiol group and a hydrocarbon group having 4 or more carbon atoms at least at one terminal of a main chain.

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To provide an optical product including an anti-fog coating film having excellent anti-fog durability. An optical product including a transparent material and an anti-fog coating film disposed on a surface of the transparent material, in which the anti-fog coating film is obtained by drying and/or curing a coating film formed from an anti-fog coating composition, the anti-fog coating composition contains a polymer (A), a substrate component (B), and a surfactant (C), the polymer (A) includes a constituent unit derived from a compound (a) having an ethylenically unsaturated group and an ionic group, a constituent unit derived from a compound (b) having an ethylenically unsaturated group and an OH group and/or an NH.sub.2 group, and a constituent unit derived from a compound (c) represented by the following formula (c-1), and has a structure derived from a compound (d) having a thiol group and a hydrocarbon group having 4 or more carbon atoms at least at one terminal of a main chain.

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