(Meth)acrylic-based flame retardant copolymer and method for manufacturing the same

1. A (meth)acrylic flame retardant copolymer comprising a phosphorus-based acrylic monomer and having an index of refraction of about 1.490 to about 1.590, wherein the phosphorus-based acrylic monomer has a structure represented by Formula 1:

wherein R 1 is —H or —(CH 2 )n-CH 3 , n is an integer from 0 to 5, and R 3 is

wherein t is an integer from 1 to 10, R 4 and R 5 are the same or different and are each independently —O(CH 2 ) q X, q is an integer from 0 to 3, and X is methyl, cyclohexyl, phenyl, methylphenyl, methylethylphenyl, propylphenyl, methoxyphenyl, cyclohexylphenyl, chlorophenol, bromophenyl, phenylphenyl or benzylphenyl.

2. The (meth)acrylic flame retardant copolymer according to claim 1 , further comprising: a (meth)acrylic monomer having an index of refraction from about 1.4950 to about 1.6500; and a reactive unsaturated monomer.

3. The (meth)acrylic flame retardant copolymer according to claim 2 , wherein the (meth)acrylic monomer has a structure represented by Formula 2, a structure represented by Formula 3, or a combination thereof:

wherein R 1 is —H or —(CH 2 )n-CH 3 , n is an integer from 0 to 5, m is an integer from 0 to 10, and X is cyclohexyl, phenyl, methylphenyl, methylethylphenyl, methoxyphenyl, propylphenyl, cyclohexylphenyl, chlorophenyl, bromophenyl, phenylphenyl or benzylphenyl,

wherein R 1 is —H or —(CH 2 )n-CH 3 , n is an integer from 0 to 5, m is an integer from 0 to 10, Y is oxygen or sulfur, and Ar is cyclohexyl, phenyl, methylphenyl, methylethylphenyl, methoxyphenyl, cyclohexylphenyl, chlorophenyl, bromophenyl, phenylphenyl or benzylphenyl.

4. The (meth)acrylic flame retardant copolymer according to claim 2 , wherein the reactive unsaturated monomer comprises a (meth)acrylic acid ester, unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, acid anhydride, unsaturated carboxylic acid ester containing hydroxyl group, unsaturated carboxylic acid amide or a combination thereof.

5. The (meth)acrylic flame retardant copolymer according to claim 4 , wherein the acrylic acid ester includes methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, or a combination thereof; the methacrylic acid ester includes methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, benzyl methacrylate or a combination thereof; the unsaturated carboxylic acid includes acrylic, acid methacrylic acid or a combination thereof the unsaturated carboxylic acid anhydride includes maleic anhydride; the unsaturated carboxylic acid ester containing hydroxyl group includes 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, monoglycerol acrylate or a combination thereof and the unsaturated carboxylic acid amide includes acrylic amide, methacrylic amide or a combination thereof.

6. The (meth)acrylic flame retardant copolymer according to claim 2 , wherein the flame retardant copolymer comprises: about 1 wt % to about 50 wt % of the phosphorus-based acrylic monomer; about 1 wt % to about 99 wt % of the (meth)acrylic monomer; and about 0 wt % to about 98 wt % of the reactive unsaturated monomer.

7. The (meth)acrylic flame retardant copolymer according to claim 1 , wherein the (meth)acrylic flame retardant copolymer has a flame retardancy of V2 or more, as measured on a 3.2 mm thick specimen in accordance with UL94.

8. The (meth)acrylic flame retardant copolymer according to claim 1 , wherein the (meth)acrylic flame retardant copolymer has a total light transmittance of about 85% or more, as evaluated on a 2.5 mm thick specimen in accordance with ASTM D1003.

9. The (meth)acrylic flame retardant copolymer according to claim 1 , wherein the (meth)acrylic flame retardant copolymer has a weight average molecular weight of about 5,000 g/mol to about 500,000 g/mol.

10. A resin composition comprising the (meth)acrylic flame retardant copolymer according to claim 1 .

11. The resin composition according to claim 10 , further comprising: at least one additive selected from the group consisting of flame retardants, surfactants, nucleating agents, coupling agents, fillers, plasticizers, impact modifiers, lubricants, antibacterial agents, release agents, heat stabilizers, antioxidants, light stabilizers, compatibilizers, organic additives, colorants, stabilizers, lubricating agents, antistatic agents, pigments, dyes, fire-proofing agents, and mixtures thereof.

12. A molded article produced from the resin composition according to claim 11 .

13. The (meth)acrylic flame retardant copolymer according to claim 1 , wherein X is cyclohexyl, phenyl, methylphenyl, methylethylphenyl, propylphenyl, methoxyphenyl, cyclohexylphenyl, chlorophenyl, bromophenyl, phenylphenyl or benzylphenyl.

14. The resin composition according to claim 10 , further comprising a polycarbonate resin, a polyethylene resin, a polystyrene resin, or a combination thereof.