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We investigated reactive fluorinated (meth)acrylate monomers and macromonomers that caused segregation at the cured resin surface of a viscous hydroxy-containing monomer, glycerol 1,3-diglycerolate diacrylate (GDD), and decreased the demolding energy in ultraviolet (UV) nanoimprinting with spin-coated films under a condensable alternative chlorofluorocarbon gas atmosphere. The X-ray photoelectron spectroscopy and contact angle measurements used to determine the surface free energy suggested that a nonvolatile silicone-based methacrylate macromonomer with fluorinated alkyl groups segregated at the GDD-based cured resin surface and decreased the surface free energy, while fluorinated acrylate monomers hardly decreased the surface free energy because of their evaporation during the annealing of the spin-coated films. The average demolding energy of GDD-based cured resins with the macromonomer having fluorinated alkyl groups was smaller than that with the macromonomer having hydrocarbon alkyl groups. The fluorinated alkyl groups were responsible for decreasing the demolding energy rather than the polysiloxane main chains. We demonstrated that the GDD-based UV-curable resin with the fluorinated silicone-based macromonomer was suitable for step-and-repeat UV nanoimprinting with a bare silica mold, in addition to silica molds treated by chemical vapor surface modification with trifluoro-1,1,2,2-tetrahydropropyltrimethoxysilane (FAS3) and tridecafluoro-1,1,2,2-tetrahydrooctyltrimethoxysilane (FAS13).

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The authors prepared ultraviolet (UV)-cured resin films with glycerin 1,3-dimethacrylate (GDM), modified by the addition of reactive fluoroalkyl acrylates. The authors then measured the decrease in the surface free energy of these materials to investigate their potential for successful demolding in UV nanoimprinting with unmodified silica molds. The fluoroalkyl acrylates of CHF2-terminus hexadecafluoro-1,1,9-trihydrononyl acrylate (16F-AC) and octafluoro-1,1,5-trihydropentyl acrylate (8F-AC) and CF3-terminus heptafluoro-1,1,2,2-tetrahydrodecyl acrylate (17F-AC) were used. The addition of 16F-AC, with its fluorinated long alkyl chain, to GDM effectively decreased the surface free energies, in comparison with 8F-AC. The solubility of 17F-AC in GDM improved in the presence of the 16F-AC and 8F-AC. As a result, the cured resin films made with the ternary monomers of GDM, 17F-AC, and 16F-AC or 8F-AC showed low surface free energies at small fluorine atomic percentages in comparison with the cured resin films made with the binary monomers of GDM and 17F-AC, 16F-AC, or 8F-AC. X-ray photoelectron spectroscopy showed that the decrease in surface free energy in the ternary monomer system can be attributed to the effective surface segregation of the fluorinated alkyl moieties because of co-assembly of the fluoroalkyl acrylates. 16F-AC and 8F-AC function as surface segregation auxiliary agents for 17F-AC. Although it was difficult to perform repeated UV nanoimprinting in air, the ternary UV-curable resin with 17F-AC resulting in a low surface energy allowed step-and-repeat UV nanoimprinting using bare silica molds in a 1,1,1,3,3-petafluoropropane atmosphere.

The syntheses of novel graft copolyamides containing both of poly( ethylene oxide) (PEO) and polydimethylsiloxane (PDMS) in the side chains were carried out by a macromonomer method, in order to develop a new functional membrane material which were expected to possess the high permeability of PDMS and the functionality of PEO-metal complex. For this purpose, 3,5-bis(4-carboxyphenyloxy)phenyloxy-terminated PEO (BCPP-PEO) and 3,5-bis(4aminophenoxy)benzyloxypropyl-terminated PDMS (BAPB-PDMS) were synthesized as macromonomers. The polycondensations of BCPP-PEO and BAPB-PDMS yielded the desired PDMS/PEO alternately grafted aromatic polyamide (P A-g-SE). Copolymer membranes were prepared by solvent casting method, and the gas permeability of these membranes was evaluated. As a result, P A-g-SE membrane exhibited the higher gas permeability than PEO-grafted polyamide membrane (P A-g-PEO). Furthermore, the selectivity of olefin gas through the membrane was effectively advanced by the addition of Ag ion to the copolymer membrane.