PVDFPVA共混膜的研究李娜娜

PVDF/PVA＊李娜娜,肖长发,安树林(,,300160)　:　采用湿法相转化法制备了聚偏氟乙烯(PVDF)/聚乙烯醇(PVA)共混膜,研究了PVDF/PVA共混体系的相容性,并讨论了PVDF/PVA共混比、固含量、添加剂浓度、凝固条件与后处理对膜结构及性能的影响。结果表明,PVDF/PVA为不相容体系,在成膜过程中产生界面微孔;随PVA含量增加,PVDF/PVA共混膜水通量先增大后减小,在PVDF/PVA为8/2时呈较大值,截留率变化趋势则相反;PVA的存在明显改善了PVDF/PVA共混膜的亲水性,表现为随其含量增加共混膜接触角明显减小;随固含量增加,膜厚度增加,孔隙率降低,水通量减小,截留率升高;添加剂PEG600浓度为6%时,孔隙率高,水通量大,但截留率低;凝固浴种类直接影响膜结构及性能;热处理可完善膜结构从而获得性能更优的膜。选择适当的铸膜条件可制成较好的膜产品,而且共混膜通量明显大于各组分通量的加权,表明共混是一种改善PVDF膜性能的有效方法。:　PVDF/PVA;;;:　TQ028.8:A:1001-9731(2007)12-1975-061　　(PVDF),C—F,(486kJ/mol),PVDF、、,、,[1,2]。,PVDF,PVDF,,PVDF[3～5]。[6],PVDFPVDF/(PEG),PVDF/(PMMA),PVDF/(PAN),PVDF/6(PA6),PVDF/(CA)PVDF/(PEO)[7～12]。(PVA)[13],,PVDF,。。PVDF/PVA,PVDF/PVA、、、,PVDF,PVDF/PVA。2　　2.1　W#1300,;2099,;(DMSO),,;、、600,。2.2　PVDF/PVA,PVDF/PVADMSO,,,。PVDF/PVA(90/10、80/20、70/30、50/50,)PVDF9、PVDF8、PVDF7、PVDF5。,。2.3　2.3.1　0.1MPaPVDF/PVA。15min,,:J=VS×t(1)　　,V(ml),S(cm2),t(h)。2.3.2　2g/L,0.1MPa、,UV-2450280nm。:R=1-2C2C0+C1×100%(2)　　,C0,C1,C2。2.3.3　,:1975:PVDF/PVA＊:(973)(2006CB708602);(20040058002):2007-05-17:2007-08-13　　　　::　(1982-),,,,,。功　　能　　材　　料ε=1-ρbρt×100%(3)　　,ρb,ρt。2.3.4　FEIQuanta200(SEM)PVDF/PVA,,。2.3.5　JY-820PVDF/PVA8,,10s。3　3.1　Hansen,、[14],:δ=δ2d+δ2p+δ2h　　,d、p、h、。Hildebrandδ[15],:ΔHm=φ1φ2[(δd1-δd2)2+(δp1-δp2)2+(δh1-δh2)2]　　,φ1φ2,δd1δd2,δp1δp2,δh1δh2。,δ,δd,δp,δh,ΔHm,。:PVAδd1=16.3,δp1=19.2,δh1=3.3;PVDFδd2=16,δp2=14.3,δh2=23.9。δh1δh2,PVDF/PVA。3.2　PVDF/PVA1(a-1)、(f-1),PVDFPVA,PVDFPVA,PVA,PVDF7(1(a-1)、(b-1)、(c-1)、(d-1)())。PVDFPVAPVDF/PVA,,,PVA,,(1(a-2、b-2、c-2)())。PVA,PVDF/PVA,,(1(d-2、e-2)),PVDF7PVDFPVA,PVDF,PVDF5,PVA[16],PVA(1(e-3)())。1DMSO,PEG6000,20℃20%。图1　PVDF/PVA共混膜上、下表面及断面的SEM图像Fig1EffectofPVDF/PVAblendratioonmicrostructureofblendmembranes　　2。PVDFPVA0.1MPa。PVDF/PVA。,PVA1976200712(38),,PVDF8,PVDF/PVA,,。:PVDF/PVA,,,PVDF/PVA。PVA,,,,,、,;PVA,PVDFPVA,,(1(d-2、e-2)),。2DMSO,PEG6000,20℃20%。图2　PVDF/PVA共混比对共混膜水通量的影响Fig2EffectofPVDF/PVAblendratioonperform-anceofthemembranes　　PVDF,(7.83N/m),PVA。3,PVA,PVDF/PVA,PVA。,,PVA,。PVDF/PVA,,PVA[24],。,、3,,,,。,PVDF7。3DMSO,PEG6000,20℃20%。图3　PVDF/PVA共混比对共混膜接触角的影响Fig3EffectofPVDF/PVAblendratioonthecontactangleofPVDF/PVAblendmembranes3.3　4,,,,,。,,,,。4DM-SO,PVDF/PVA8/2,PEG6006%,20℃。4(a);(b)、SEM;(c)。图4　固含量对共混膜性能的影响Fig4Effectofpolymerconcentrationonperformanceofblendmembranes　　SEM,15%(5(a)),,,;20%(5(b)),,,;25%(5(c)),,,。5DMSO,PVDF/PVA8/2,PEG6006%,20℃。3.4　6、7,PEGPEG,,(7(a,b)),,,,,;PEG,[17],,,,(7(c)),,,,,;PEG,PEGPVA1977:PVDF/PVA功　　能　　材　　料,,,(7(d,e)),,,,。图5　不同固含量的PVDF/PVA共混膜SEM图像(×1000)Fig5Effectofpolymerconcentrationonmicrostructureofblendmembranes(×1000)图6　PEG600含量对共混膜孔隙率的影响及膜上、下表面SEM图和对水通量及截留率的影响Fig6EffectofPEG600concentrationonperformanceofthemembranes　　6DMSO,20%,PVDF/PVA8/2,PEG6000,20℃。7DMSO,20%,PVDF/PVA8/2,PEG6000,20℃。3.5　10min,,8。8DM-SO,20%,PVDF/PVA8/2,PEG6000,20℃。,,,,40℃,80℃,,,。,,,;,;PVA,,。图7　不同添加剂含量的PVDF/PVA共混膜SEM图像Fig7EffectofPEG600concentrationonmicrostructureofblendmembranes3.6　0.5mol/L、20%,(9、10),:,(9(a)),,(10(c)),,,,。(10(b))。,,,,,,。,()[18]。9DMSO,20%,PVDF/PVA8/2,PEG6000,20℃。10DMSO,20%,PVDF/PVA8/2,PEG6000,20℃。图8　热处理温度对共混膜孔隙率的影响及膜上、下1978200712(38)表面SEM图和水通量及截留率的影响Fig8Effectofheattreatmenttemperatureonper-formanceofthemembranes图9　凝胶浴种类对共混膜孔隙率的影响及膜上、下表面SEM图和水通量及截留率的影响Fig9Effectofcoagulationbathonperformanceofthemembranes图10　不同凝固浴的PVDF/PVA共混膜SEM图像(×700)Fig10Effectofpolymerconcentrationonmicrostructureofblendmembranes(×700)4　　PVDF/PVA,;PVA,PVDF/PVA,PVDF/PVA8/2,;PVAPVDF/PVA,;,,,,,20%;PEG600,PEG6006%,;,,,;,,,,40℃,,80℃,,,,,。:[1]　DohanyJE,RobbLE.PolyvinylideneFluoride,in:Kirk-OthmerEncyclopediaofChemicalTechnology[M].NewYork:Wiley,1980.64-74.[2]　LovingerAJ.[J].ApplSci,1982,1:195.[3]　BroseJ,Daniel,Friesen,etal.ManufactureofHydrophilicPoly(VinylideneFluoride)(PVDF)Membranes[P].US:5,476,590,1995.[4]　JanJ.FoulinginPolymericMembranemodifiedwithLowTemperaturePlasma[C].Missouri:ColumbiaUniversityofMissouri,1997.[5]　WangP,TanKL,KangET,etal.[J].JMembraneSci,2002,195:103.[6]　ChandavasuC,XanthosM,SirkarKK,etal.[J].JMem-braneSci,2003,211:167.[7]　UragamiT,NaitoY,SuginaraM.[J].PolymBull,1981,4:617.[8]　NunesSP,PeinemannKV.[J].JMembraneSci,1992,73:25.1979:PVDF/PVA功　　能　　材　　料[9]　TingyuL,WenchingL,LiyingH,etal.[J].PolymAdvTechnol,2005,16:413.[10]　MasciaL,HashimK.[J].JApplPolymSci,1997,66:1911.[11]　ZhanW,YawenL,ShumeiW,etal.[J].MembraneSciTechnol,2005,22:5.[12]　JingyuX,XinpingQ.[J].JPowerSources,2006,157:501.[13]　Turner,JohnShenJ,MitchelL,etal.[J].JApplPolymSci,1980,25:1287.[14]　VanKrevelenDW.PropertiesofPolymers-theirEstima-tetonandCorrelateionwithChemicalStructure[M].NewYork:Elsevier,1976.[15]　HildebrandJH,ScottRL.TheSolubilityofNon-elec-trolytesReinhold[M].NewYork:Wiley,1949.[16]　.[J].,1991,11(6):4.[17]　KestingRE.SyntheticPolymericMembranes[M].NewYork:AStructuralPerspective,1985.[18]　　,,.[J].,1992,18(2):84.PreparationandpropertiesofPVDF/PVAblendmembranesLINa-na,XIAOChang-fa,ANShu-lin(TheKeyLaboratoryofHollowFiberMembraneMaterialandProcessofMinistryofEducation,DepartmentofMaterialsScience&Engineering,TianjinPolytechnicUniversity,Tianjin300160,China)Abstract:ThemembranewaspreparedfromPVDF/PVAblendpolymerbyL-Sphaseinv