Cross-linked poly (aspartic acid) product and method for producing same

A cross-linked poly(aspartic acid) product, wherein the cross-linked poly(aspartic acid) product is a reaction product of:

• a polysuccinimide (PSI),
• a compound (A:
• a1-A1-a2) containing a first functional group (a1) and a second functional group (a2), and
• a polyfunctional epoxy compound (B),
• wherein the cross-linked poly(aspartic acid) product contains a PSI-a1(A) bond formed by an addition reaction of the first functional group (a1) with the polysuccinimide (PSI),
• the cross-linked poly(aspartic acid) product contains a B-a2(A) bond formed by a reaction of the second functional group (a2) with the polyfunctional epoxy compound (B),
• the cross-linked poly(aspartic acid) product contains a cross-linked structure (PABAP) represented by PSI-a1-A1-a2-B-a2-A1-a1-PSI,
• the cross-linked structure (PABAP) is partially hydrolyzed, and
• wherein the second functional group of the compound (A) does not react with the polysuccinimide (PSI) or is less reactive with the polysuccinimide (PSI) than the first functional group,
• the first functional group (a1) is an amino group (NH2—),
• the second functional group (a2) is one or more selected from the group consisting of an amino group (NH2—) and a phosphonooxy group ((OH)2P(═O)—O—), and
• when the second functional group (a2) is an amino group (NH2—), the second functional group is less reactive with the polysuccinimide (PSI) than the first functional group (a1).