Two- and Three-Dimensional Smectic Ordering of Single-Handed Helical Polymers(10)

Two- and Three-Dimensional Smectic Ordering of Single-Handed Helical Polymers

ARTICLESstate,assistedbyfoursetsofintramolecularhydrogen-bondinghelicalarraysofthependants.Inaddition,thehelicalstructuresofthepolyisocyanidesincludingthehelicalpitchandhanded-nesswereforthefirsttimedeterminedbyhigh-resolutionAFMobservationscombinedwithX-raydiffractionmeasurements.WeanticipatethatthehelicalpolyisocyanidesbearingPtandPdattheendsmayalsobeusedasanoveltemplatetoorganizeone-dimensionalarraysofinorganicmaterialsonthenanoscalebymodificationofthecatalyst,whichmaybeapplicabletothenext-generationoptical,electric,andmagneticdevices.

ExperimentalSection

Instruments.TheNMRspectraweremeasuredusingaVarianAS500spectrometer(Varian,PaloAlto,CA)operatingat500MHzfor1Hand125MHzfor13C,usingTMSastheinternalstandard.TheIRspectrawererecordedusingaJASCOFT/IR-680spectrometer(JASCO,Tokyo,Japan).TheabsorptionandCDspectrawereobtainedina1.0-mmquartzcellusingaJASCOV570spectrophotometerandaJASCOJ820spectropolarimeter,respectively.Thepolymerconcen-trationwascalculatedonthebasisofthemonomerunitsandwas0.2mg/mL.Theopticalrotationsweremeasuredina2-cmquartzcellonaJASCOP-1030polarimeter.SECwasperformedusingaJASCOPU-2080liquidchromatographequippedwithUV-visible(JASCOUV-2070)andCD(JASCOCD-2095)detectors.TwoTosohTSKgelMultiporeHXL-MSECcolumns(Tosoh,Tokyo,Japan)wereconnectedinseries,andTHFcontaining0.1wt%tetra-n-butylammoniumbromidewasusedastheeluentattheflowrateof1.0mL/min.Themolecularweightcalibrationcurvewasobtainedwithstandardpolystyrenes(Tosoh).TheWAXDmeasurementswerecarriedoutusingaRigakuRINTRAPID-RX-raydiffractometer(Rigaku,Tokyo,Japan)witharotating-anodegeneratorandgraphitemonochromatedCuKRradiation(0.15418nm)focusedthrougha0.3mmpinholecollimator,whichwassuppliedata45kVvoltageanda60mAcurrent,equippedwithacurvedimagingplatehavingaspecimen-to-platedistanceof120.0mm.TheX-rayphotographsweretakenatambienttemperature(20-25°C)fromtheedge-viewpositionwithabeamparalleltothefilmsurface.TheSEC-MALSmeasurementswereperformedusinganHLC-8220GPCsystem(Tosoh)equippedwithadifferentialrefrac-tometercoupledtoaDAWN-EOSMALSdeviceequippedwithasemiconductorlaser(λ)690nm)(WyattTechnology,SantaBarbara,CA)operatedat25°CusingtwoTSKgelMultiporeHXL-Mcolumns(Tosoh)inseries.Thescatteredlightintensitiesweremeasuredby18light-scatteringdetectorsatdifferentangles.Thedifferentialrefractiveindexincrement,dn/dc,ofthepolymerwithrespecttothemobilephaseat25°CwasalsomeasuredbyanOptilabrEXinterferometricrefractometer(WyattTechnology).TheAFMmeasurementswereperformedusingaNanoscopeIIIaorNanoscopeIVmicroscope(VeecoInstruments,SantaBarbara,CA)inairatambienttemperature(ca.25°C)withstandardsiliconcantilevers(NCH,NanoWorld,Neufcha tel,Switzerland)inthetappingmode.ThepolarizingopticalmicroscopicobservationswerecarriedoutwithanE600POLpolarizingopticalmicroscope(Nikon,Tokyo,Japan)equippedwithaDS-5MCCDcamera(Nikon)connectedtoaDS-L1controlunit(Nikon).Thesamplesolutionwasplacedonaglassplatewithacoverglasstodeveloptheplanarstructurebeforeobservationofthemicroscopictextureatambienttemperature(20-25°C).TheSR-SAXSmeasurementswereperformedattheInstituteofMaterialsStructureScience,Tsukuba,Japan(PhotonFactory),withsmall-angleX-rayequipmentinstalledonabeamline,BL15A,withtheapprovalofthePhotonFactoryProgramAdvisoryCommittee(No.2006G293).ThewavelengthoftheincidentX-raybeamwas0.1508nm.X-rayphotographsweretakenusingaflatimagingplateplaced2400mmfromthesamplepositionatambienttemperature(20-25°C).TheTEMobservationswereperformedusingaHitachiH-800instrumentoperatedat100kV.Thesamplewaspreparedbycastingaconcentratedsolutionofpoly-D-1(+)inchloro-234J.AM.CHEM.SOC.

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