Process of controlled radical polymerization of branched polyacrylates

1. A process of controlled radical polymerization, comprising the steps of:

i) performing controlled radical polymerization on a mixture comprising a mono-functional acrylate monomer, an initiator, a ligand, and a metal catalyst;

ii) permitting the controlled radical polymerization reaction to proceed until a desired level of conversion is attained, but prior to complete conversion, to obtain an intermediate polymerization product; and

iii) further reacting the intermediate polymerization product with an acrylate monomer having multiple acrylate functional groups to provide a branched polymer chain.

2. The process of claim 1 , wherein the controlled radical polymerization is a single electron transfer living radical polymerization.

3. The process of claim 1 , wherein the acrylate monomer having multiple acrylate functional groups is selected from the group consisting of 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,4-butanediol diacrylate, 1,3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, trans-1,4-cyclohexanediol dimethacrylate, N,N′-diallylacrylamide, diethylene glycol diacrylate, diethylene glycol dimethacrylate, 2,2-dimethylpropanediol dimethacrylate, dipropylene glycol dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, N,N′-hexamethylene bisacrylamide, 1,5-pentanediol dimethacrylate, 1,4-phenylene diacrylate, pentaerythritol triacrylate, 1,1,1-trimethylolpropane triacrylate, 1,1,1-trimethylolpropane trimethacrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, and combinations thereof.

4. The process of claim 1 , wherein said mono-functional acrylate monomer is a (meth)acrylate monomer is selected from the group consisting of (meth)acrylic acid, methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate, isobutyl(meth)acrylate, tert-butyl(meth)acrylate, n-pentyl(meth)acrylate, n-hexyl(meth)acrylate, cyclohexyl(meth)acrylate, n-heptyl(meth)acrylate, n-octyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, nonyl(meth)acrylate, decyl(meth)acrylate, dodecyl(meth)acrylate, phenyl(meth)acrylate, toluyl(meth)acrylate, benzyl(meth)acrylate, 2-methoxyethyl(meth)acrylate, 3-methoxybutyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, stearyl(meth)acrylate, glycidyl(meth)acrylate, 2-aminoethyl(meth)acrylate, [−](methacryloyloxypropyl)trimethoxysilane, (meth)acrylic acid-ethylene oxide adducts, trifluoromethylmethyl(meth)acrylate, 2-trifluoromethylethyl(meth)acrylate, 2-perfluoroethylethyl(meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl(meth)acrylate, 2-perfluoroethyl(meth)acrylate, perfluoromethyl(meth)acrylate, diperfluoromethylmethyl(meth)acrylate, 2-perfluoromethyl-2-perfluoroethylethyl(meth)acrylate, 2-perfluorohexylethyl(meth)acrylate, 2-perfluorodecylethyl(meth)acrylate and 2-perfluorohexadecylethyl(meth)acrylate, and combinations thereof.

5. The process of claim 1 , wherein said mono-functional acrylate monomer is a member selected from the group consisting of n-butyl acrylate, methyl methacrylate, methoxy ethylacrylate, ethyl acrylate, (meth)acrylonitrile, and combinations thereof.

6. The process of claim 1 , wherein said initiator is selected from the group consisting of mono-halogenated compounds, poly-halogenated compounds, and combinations thereof.

7. The process of claim 1 , wherein the initiator conforms to the formulas R—X or R′C(═O)OR, wherein X is a halogen and R is C 1 -C 6 alkyl.

8. The process of claim 1 , wherein the initiator is selected from the group consisting of diethyl meso-2,5-dibromoadipate, dimethyl 2,6-dibromoheptanedioate, ethylene glycol bis(2-bromopropionate), ethylene glycol mono-2-bromopropionate, trimethylolpropane tris(2-bromopropionate), pentaerythritol tetrakis (2-bromopropionate), 2,2-dichloacetophenone, methyl 2-bromopropionate, methyl 2-chloropropionate, N-chloro-2-pyrrolidinone, N-bromosuccinimide, polyethylene glycol bis(2-bromopropionate), polyethylene glycol mono(2-bromopropionate), 2-bromopropionitrile, dibromochloromethane, 2,2-dibromo-2-cyanoacetamide, α,α′-dibromo-ortho-xylene, α,α′-dibromo-meta-xylene, α,α′-dibromo-para-xylene, α,α′-dichloro-para-xylene, 2-bromopropionic acid, methyl trichloroacetate, para-tolunesulfonyl chloride, biphenyl-4,4′-disulfonyl chloride, diphenylether-4,4′-disulfonylchloride bromoform, iodoform carbon tetrachloride, and combinations thereof.

9. The process of claim 1 , wherein the initiator is diethyl meso-2,5-dibromoadipate or dimethyl 2,6-dibromoheptanedioate.

10. The process of claim 1 , wherein the ligand is selected from the group consisting of primary alkyl or aromatic amines, secondary alkyl or aromatic amines, tertiary alkyl or aromatic amines, linear polyamines, branched polyamines, dendritic polyamines, polyamides and combinations thereof.

11. The process of claim 1 , wherein the ligand is selected from the group consisting of tris(2-dimethylaminoethyl)amine, tris(2-aminoethyl)amine, 2,2-bipyridine N,N,N,N,N-pentamethyldiethylenetriamine, and combinations thereof.

12. The process of claim 1 , wherein the metal catalyst is selected from the group consisting of Cu(0), Cu 2 S, Cu 2 Te, Cu 2 Se, Mn, Ni, Pt, Fe, Ru, V, Au, Ag, Hg, Rh, Co, Ir, Os, Re, Mn, Cr, Mo, W, Nb, Ta, Zn and combinations thereof.

13. The process of claim 1 , wherein the metal catalyst is Cu(0).

14. The process of claim 1 , wherein the branched polymer chain from the process has a polydispersity of about 1.0 to about 1.3.

15. A branched polymer compound having a polydispersity of about 1.3 or less.

16. A branched polymer reaction product having a polydispersity of about 1.0 to about 1.9 formed by a process having the steps of:

i) performing controlled radical polymerization on a mixture comprising a mono-functional polymerizable component, an initiator, a ligand, and a metal catalyst;

ii) permitting the controlled radical polymerization reaction to proceed until a desired level of conversion is attained, but prior to complete conversion to obtain an intermediate polymerization product; and

iii) further reacting the intermediate polymerization product with an acrylate monomer having multiple acrylate functional groups to provide a branched polymer chain.

17. An article of manufacture comprising the branched polymer reaction product of claim 16 .

18. An adhesive, sealant, or coating composition comprising:

(a) a branched polymer reaction product having a polydispersity of about 1.0 to about 1.9 formed by a process having the steps of:

i) performing controlled radical polymerization on a mixture comprising a mono-functional acrylate monomer, an initiator, a ligand, and a metal catalyst;

ii) permitting the controlled radical polymerization reaction to proceed until a desired level of conversion is attained, but prior to complete conversion to obtain an intermediate polymerization product; and

iii) further reacting the intermediate polymerization product with an acrylate monomer having multiple acrylate functional groups to provide a branched polymer chain.

19. The composition of claim 18 , further comprising a cure system.

20. The composition of claim 18 , further comprising a component selected from the groups consisting of monomers, polymers, plasticizers, thickening agents, rheology agents, coloring agents, pigments, fillers, initiators, and combinations thereof.