We describe a simple route to fabricate two dimensionally well-ordered, periodic nanopatterns using the self-assembly of brush block copolymers (brush BCPs). Well-developed lamellar microdomains oriented perpendicular to the substrate are achieved, without modification of the underlying substrates, and structures with feature sizes greater than 200 nm are generated due to the reduced degree of chain entanglements of brush BCPs. A near-perfect linear scaling law was found for the period, L, as a function of backbone degree of polymerization (DP) for two series of brush BCPs. The exponent increases slightly from 0.99 to 1.03 as the side chain molecular weight increases from ∼2.4 to ∼4.5 kg/mol–1 and saturated with further increase in the side chain molecular weight due to the entropic penalty associated with the packing of the side chains. Porous templates and scaffolds from brush BCP thin films are also obtained by selective etching of one component.

A simple method was developed to realize a self-assembled block copolymer (BCP) lamellar microdomain morphology with a full pitch of 5.4 nm through an acid hydrolysis of poly(solketal methacrylate-b-styrene) (PSM-b-PS). The acid hydrolysis transforms PSM-b-PS, having two hydrophobic blocks, into poly(glycerol monomethacrylate-b-styrene) (PGM-b-PS), having one hydrophilic and one hydrophobic block. This transformation markedly increases the segmental interaction parameter such that a phase-mixed PSM-b-PS can be transformed in the solid state into a microphase-separated BCP without the use of any additives. Correlation hole scattering of the PSM-b-PS in the phase mixed state yields a segmental interaction parameter (χ) given by χ = 0.0196 + 4.694/ T, where T is the absolute temperature. With the symmetric BCPs used in this study, the ordered lamellar microdomain pitch was determined by small-angle X-ray scattering (SAXS) as a function of the degree of polymerization (16 ≤ N ≤ 1246). For the lamellar microdomains of PGM-b-PS, the scattering profiles show many higher order reflections with an increase in the domain spacing (L 0 ). The lowest molar mass sample (M n = 2200 g/mol, N = 16) had sub-3 nm microdomains after conversion to PGMb-PS.

Low molecular weight P2VP-b-PS-b-P2VP triblock copolymer (poly(2-vinlypyridine)-block-polystyrene-block-poly(2-vinylpyridine)] is doped with copper chloride and microphase separated into lamellar line patterns with ultrahigh area density. Salt-doped P2VP-b-PS-b-P2VP triblock copolymer is self-assembled on the top of the nanoimprinted photoresist template, and metallic nanowires with long-range ordering are prepared with platinum-salt infiltration and plasma etching.

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