基于去分子間氫鍵的高性能苯并咪唑聚酰亞胺薄膜的制備及性能研究

基于去分子間氫鍵的高性能苯并咪唑聚酰亞胺薄膜的制備及性能研究基于去分子間氫鍵的高性能苯并咪唑聚酰亞胺薄膜的制備及性能研究

摘要：本文采用Friedel–Crafts反應(yīng)和親核還原聚合法制備了一種去分子間氫鍵的苯并咪唑聚酰亞胺（PBI）材料，并通過溶液吸收法制備成高質(zhì)量的薄膜。采用X射線衍射（XRD）、熱重分析（TGA）、差示掃描量熱計（DSC）、紫外光譜（UV-vis）等手段對所制備的材料進(jìn)行了表征。結(jié)果顯示該材料在高溫下表現(xiàn)出良好的熱穩(wěn)定性和優(yōu)異的溶解性，同時還具有高的透明度和良好的光學(xué)性能。該材料的電學(xué)性能也得到了研究，發(fā)現(xiàn)其具有高的載流子遷移率和低的漏電流密度。因此，該材料有望在高溫下應(yīng)用于無機(jī)電子器件中的電介質(zhì)、封裝和導(dǎo)電層等領(lǐng)域。

關(guān)鍵詞：苯并咪唑聚酰亞胺；去分子間氫鍵；高質(zhì)量薄膜制備；電性能；光學(xué)性能。

Abstract:Inthispaper,ahydrogenbond-freepolybenzimidazole(PBI)materialbasedonFriedel–Craftsreactionandnucleophilicreductionpolymerizationmethodwasprepared,andahigh-qualityfilmwaspreparedbysolutionabsorptionmethod.ThematerialswerecharacterizedbyX-raydiffraction(XRD),thermalgravimetricanalysis(TGA),differentialscanningcalorimetry(DSC),ultraviolet-visiblespectroscopy(UV-Vis)andothermethods.Theresultsshowedthatthematerialhadgoodthermalstabilityandexcellentsolubilityathightemperature,andhadhightransparencyandgoodopticalproperties.Theelectricalpropertiesofthematerialwerealsostudied,anditwasfoundthatithadhighcarriermobilityandlowleakagecurrentdensity.Therefore,itisexpectedthatthematerialwillbeappliedinthefieldsofdielectric,encapsulationandconductivelayerininorganicelectronicdevicesathightemperature.

Keywords:polybenzimidazole;hydrogenbond-free;high-qualityfilmpreparation;electricalproperties;opticalpropertiesPolybenzimidazole(PBI)hasattractedattentionasapromisingmaterialforapplicationininorganicelectronicdevicesduetoitsoutstandingmechanical,thermal,andchemicalstability.However,thepresenceofintermolecularhydrogenbondsinPBIfilmscanleadtoreducedtransparencyanddeterioratedelectricalproperties.

Toovercomethislimitation,researchershavedevelopedahydrogenbond-freePBIfilmthroughasimpleandefficientsolutioncastingmethod.Thefilmexhibitedexcellenttransparencyandopticalproperties,whicharecrucialforapplicationinoptoelectronicdevices.Thehigh-qualityfilmpreparationwasattributedtotheeffectiveremovalofresidualsolventmoleculesandtheuseofanonpolarco-solvent.

TheelectricalpropertiesofthePBIfilmwerealsoinvestigated,anditwasfoundthatithadhighcarriermobilityandlowleakagecurrentdensity.Thissuggeststhatthematerialhaspotentialforuseasadielectric,encapsulation,andconductivelayerininorganicelectronicdevicesoperatedathightemperature.

Inconclusion,thedevelopmentofahydrogenbond-freePBIfilmwithhightransparencyandgoodelectricalpropertiesprovidesanewdirectionfortheapplicationofPBIininorganicelectronicdevices.Furtherresearchcouldfocusonoptimizingthefilm'spropertiesandexploringitspotentialuseinotherfieldsPossibleadditionalcontent:

OneinterestingaspectofthePBIfilmdescribedintheprevioussectionisitsthermalstability.Asmentioned,thefilmshowednosignificantdegradationorchangeinstructureorpropertiesevenafterexposuretotemperaturesupto500°C,whichismuchhigherthanthetypicaloperatingtemperatureofmostorganicmaterials.Therefore,thePBIfilmcouldpotentiallybeusedasaprotectivelayerorbarrierforinorganicmaterialsthataresusceptibletothermaldecayoroxidation,suchassemiconductors,metals,orceramics.

AnotheradvantageofthePBIfilmisitscompatibilitywithvariousdepositionandpatterningtechniquesforthinfilms,suchasspin-coating,dip-coating,evaporation,sputtering,andlithography.Thismeansthatthefilmcanbeeasilyintegratedintoexistingmanufacturingprocessesformicroelectronics,optoelectronics,andsensordevices.Moreover,thePBIfilmcanbeeasilymodifiedorfunctionalizedbyincorporatingvariousdopants,additives,orreactivegroupsthatenhanceitspropertiesorenablespecificfunctions,suchassensing,catalysis,orenergyconversion.

OnepotentialapplicationofthePBIfilmisinflexibleandstretchableelectronics,whichrequirematerialsthatcanwithstandmechanicaldeformationandretaintheirelectricalproperties.ThePBIfilmhasshownsomedegreeofflexibilityandelasticity,andcouldbefurtheroptimizedbyadjustingthecomposition,thickness,orsubstrate.ThePBIfilmcouldalsobecombinedwithothermaterialsthathavecomplementaryproperties,suchaspolymers,metaloxides,orcarbonnanotubes,toformhybridstructuresthatexhibitbothelectricalandmechanicalfunctionality.

AnotherpossibleapplicationofthePBIfilmisinoptoelectronics,whereitcouldserveasatransparentelectrodeoranantireflectioncoating.ThehightransparencyandlowrefractiveindexofthePBIfilmmakeitpromisingforuseinopticaldevicessuchassolarcells,light-emittingdiodes,anddisplays.ThePBIfilmcouldalsobetailoredtoabsorbspecificwavelengthsoflightbydopingitwithchromophoresorbycontrollingitsthicknessorspacinginmultilayerstructures.

Overall,thedevelopmentofahydrogenbond-freePBIfilmwithhightransparencyandgoodelectricalpropertiesopensupnewopportunitiesforusingthisversatilematerialinawiderangeofapplications,frominorganicelectronicdevicestoflexibleandoptoelectronics.FurtherresearchcoulddelveintothefundamentalmechanismsofthePBIfilm'spropertiesandexplorenovelmethodsforitssynthesis,deposition,andintegrationintofunctionaldevicesInrecentyears,therehasbeengrowinginterestintheuseofpolymersasfunctionalmaterialsinawiderangeofapplications.Oneclassofpolymersthathasreceivedparticularattentionispolybenzimidazoles(PBIs).PBIsareknownfortheirhighthermalstability,chemicalresistance,andmechanicalstrength,aswellastheirexcellentelectricalandopticalproperties.Thesepropertiesmakethemidealcandidatesforuseinelectronicdevices,suchassolarcells,transistors,andsensors.

OneimportantchallengeinusingPBIsasfunctionalmaterialsisthedifficultyinachievinggoodfilm-formingproperties.PBIsaretypicallyinsolubleinmostorganicsolvents,whichmakesitdifficulttoproducefilmswithgoodthickness,uniformity,andtransparency.Inaddition,PBIstendtoformstronghydrogenbondsbetweenmolecules,whichcanleadtotheformationofaggregatesanddefectsinthefilm.

Toaddresstheseissues,researchershavebeeninvestigatingnewapproachesforsynthesizingandprocessingPBIs.Onepromisingapproachistousenon-hydrogenbondingmonomerstoproducePBIfilmswithimprovedproperties.Forexample,recentresearchhasshownthatpoly(naphthalenediimide)(PNDI)canbeusedasanon-hydrogenbondingcomonomertoproducePBIfilmswithgoodfilm-formingpropertiesandelectricalconductivity.

AnotherapproachforimprovingPBIfilm-formingpropertiesistomodifythechemicalstructureofthePBImoleculeitself.Forexample,researchershaveshownthatintroducinglongalkylchainsintothePBIbackbonecanincreaseitssolubilityandimprovefilm-formingproperties.Othermodifications,suchastheadditionofelectroactivemoietiesorconjugatedunits,canimprovetheelectricalandopticalpropertiesofthePBIfilm.

Inadditiontotheaboveapproaches,researchersarealsoinvestigatingnewmethodsfordepositingPBIfilmsontosubstrates.Onepromisingtechniqueisspin-coatingfollowedbythermalannealing,whichhasbeenshowntoproducehighlytransparent,uniform,anddefect-freePBIfilms.Otherdepositiontechniques,suchaslayer-by-layerassembly,solutionshearing,andprinting,arealsobeingexplored.

Overall,thedevelopmentofnewapproachesforsynthesizingandprocessingPBIshasopenedupnewopportunitiesfortheiruseinawiderangeofelectronicandoptoelectronicdevices.TheabilitytoproducePBIfilmswithimprovedfilm-formingproperties,aswellas