Copolymer formulation for directed self assembly, methods of manufacture thereof and articles comprising the same
Disclosed herein is a method comprising disposing upon a substrate a composition comprising a block copolymer; where the block copolymer comprises a first polymer and a second polymer; where the first polymer and the second polymer of the block copolymer are different from each other and the block copolymer forms a phase separated structure; an additive polymer; where the additive polymer comprises a reactive moiety that is operative to react with a substrate upon which it is disposed; and where the additive polymer comprises a homopolymer that is the chemically and structurally the same as one of the polymers in the block copolymer or where the additive polymer comprises a random copolymer that has a preferential interaction with one of the blocks of the block copolymers; and a solvent; and annealing the composition.
1. A method comprising:
disposing upon a substrate a composition comprising:
an intimate mixture of complete volumes of:
a block copolymer; where the block copolymer comprises a first polymer and a second polymer; where the first polymer and the second polymer of the block copolymer are different from each other and the block copolymer forms a phase separated structure; where the block copolymer is poly(styrene-b-vinyl pyridine), poly(styrene-b-butadiene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-(ethylene-propylene)), poly(ethylene oxide-b-caprolactone), poly(butadiene-b-ethylene oxide), poly(styrene-b-t-butyl (meth)acrylate), poly(methyl methacrylate-b-t-butyl methacrylate), poly(ethylene oxide-b-propylene oxide), poly(styrene-b-tetrahydrofuran), poly(styrene-b-isoprene-b-ethylene oxide), poly(styrene-b-trimethylsilylmethyl methacrylate), poly(methyl methacrylate-b-dimethylsiloxane), poly(methyl methacrylate-b-trimethylsilylmethyl methacrylate), or a combination comprising at least one of the foregoing copolymers;
an additive polymer; where the additive polymer comprises a reactive moiety that is operative to react with the substrate upon which it is disposed; and where the additive polymer comprises a homopolymer that is the chemically and structurally the same as one of the polymers in the block copolymer or where the additive polymer comprises a random copolymer that has a preferential interaction with one of the blocks of the block copolymers and where the reactive moiety is an amine group, a silane group or an alkoxy group; and
a solvent; and
annealing the composition to facilitate bonding or complexation or coordination of the additive polymer to the substrate and domain separation between the first polymer and the second polymer of the block copolymer to form a morphology of periodic domains formed from the first polymer and the second polymer; where a longitudinal axis of the periodic domains are parallel to the substrate surface or wherein the domains are spherical; where the second polymer is present in an amount of either 8 to 15 volume percent or 20 to 30 volume percent based on a total volume of the block copolymer.
2. The method of claim 1 , further comprising removing at least one domain of the block copolymer.
3. The method claim 1 , where the additive polymer has the structure of formulas (7A) or (7B):
where the reactive species X is the reactive moiety, R 1 , R 2 and R 3 can be the same or different and can be a hydrogen, a C 1-10 alkyl group, a C 6 -C 14 aryl, a C 7 -C 13 alkylaryl or a C 7 -C 13 arylalkyl group.
4. The method of claim 1 , where the additive polymer is a polystyrene, a polysiloxane, a polymethylmethacrylate, a polyacrylate, a polyvinylacetate, a polydiene, a polyether a polyester, a polysiloxane, a polyorganogermane, or a combination comprising at least one of the foregoing polymers.
5. The method of claim 1 , where the additive polymer is a hydroxyl terminated polystyrene, a hydroxyl terminated polydimethylsiloxane, a hydroxyl terminated poly(methylmethacrylate-random-trifluoroethylmethacrylate), a hydroxyl terminated poly(methylmethacrylate-random-dodecafluoroheptylmethacrylate), or a combination comprising at least one of the foregoing additive polymers.
6. The method of claim 1 , where the first polymer or the second polymer of the block copolymer comprises a polymer derived from monomers of a vinyl aromatic monomer, an ethylenically unsaturated monomer, 1-butene, 1,3-butadiene, isoprene, vinyl acetate, dihydropyran, norbornene, maleic anhydride, siloxane, or a combination comprising at least one of the foregoing monomers.
7. The method of claim 6 , where the vinyl aromatic monomer is styrene, o-methyl styrene, p-methyl styrene, m-methyl styrene, α-methylstyrene, o-ethyl styrene, m-ethyl styrene, p-ethyl styrene, α-methyl-p-methyl styrene, 2,4-dimethyl styrene, monochlorostyrene, p-tert-butylstyrene, 4-tert-butylstyrene, hydroxy styrene, acetoxy styrene, or a combination comprising at least one of the foregoing vinyl aromatic monomers.
8. The method of claim 6 , where the ethylenically unsaturated monomer is represented by formula (2):
where R 1 is a hydrogen or an alkyl group having 1 to 10 carbon atoms, by the formula (3):
where R 1 is a hydrogen or an alkyl group having 1 to 10 carbon atoms and R 2 is a C 1-10 alkyl, a C 3-10 cycloalkyl, or a C 7-10 aralkyl group or by the formula (4):
where R 1 is a hydrogen or an alkyl group having 1 to 10 carbon atoms and R 3 is a C 2-10 fluoroalkyl group.