脂肪族水性聚氨酯的合成及結構與性能關系的研究.pdf

1、脂肪族水性聚氨醋的合成及結構與性能關系的研究摘要本論文以異佛爾酮二異氰酸酷(IPDI)為原料，合成了多種脂肪族水性聚氨酷。整個工作可以分為3個主要部分:(1)預聚體乳化過程中的相轉變行為研究(2)乳液的粒徑大小、分布及穩(wěn)定性研究(3)水性聚氨酷結構與性能的關系研究。一倩次系統(tǒng)地研究了脂肪族水性聚氨酷預聚體乳化過程中的相轉變行為。解釋了乳化進行的機理，討論了預聚體在有機溶劑中的聚集態(tài)結構。帶有離子基團的預聚體分子可以形成鏈段微離子聚集體。

2、通過考察預聚體加水乳化過程中粘度及電導率的變化，研究了其相轉變行為.研究結果表明:乳化過程包括鏈段微離子聚集體的解聚集和疏水鏈段的聚集過程。依據(jù)乳化體系粘度和電導率的變化，可以將乳化過程劃分為3個部分.隨著軟段分子量的升高，乳化體系的相轉變點后延聚酷體系的相轉變比聚醚體系的相轉變發(fā)生得早nNCOnox值越接近1，體系的粘度就越高，相轉變發(fā)生所需的水含量也越高狡基含量及中和度也對分散體系的相轉變產(chǎn)生影響。研究得出的規(guī)律為水性聚氨醋合成條件

3、的優(yōu)化提供了理論依據(jù)。以均苯四甲酸酚和聚乙二醇600為原料，設計合成了一種新型的離子非離子復合型親水單體(K600)。并以K600、異佛爾酮二異氰酸酷(IPDI)和聚酩二元醇為原料合成了自乳化聚氨醋乳液?？疾炝薑600對乳液外觀、粒徑大小及分布、粘度、凍融穩(wěn)定性、高溫穩(wěn)定性、抗電解質能力、pH值穩(wěn)定性的影響關系。結果表明:所得產(chǎn)物具有優(yōu)異的綜合穩(wěn)定性，可以耐受80℃的長期高溫20C18h凍融5次以上仍然穩(wěn)定可與10%NaCl溶液以任意比

4、例混合可在pH=114的范圍內性質穩(wěn)定。通過動態(tài)力學分析(DMA)、應力一應變行為、紅外光譜(FTIR)等手段研究了脂肪族水性聚氨醋的結構與性能關系.研究結果表明:聚酷型軟段和硬段之間的可以形成較強的氫鍵，相容性較好:聚醚型軟段與硬段之間形成的氫鍵較弱，軟硬段相容性較差。當軟段的分子量為1000時，聚酷和聚醚型水性Investigationpolyurethanesonthesynthesisofaliphaticwaterbornea

5、ndtherelationshipsofpropertieswithstructureAbstractThesynthesisofaliphaticwaterbomepolyurethanesandtherelationshipsofpropertieswithstructurewasstudied.Itconsistsofthreemainparts:(1)thestudyonthephaseinversionbehaviorsdur

6、ingemulsificationprocess(2)thestudyonparticlesizedistributionandstabilityofwaterbomepolyurethanes(3)theinvestigationontherelationshipsbetweenmorphologyandpropertiesSeveralaliphaticwaterbornepolyurethaneprepolymersareprep

7、aredfromisophoronediisocyanate(IPDI)dimethylolpropanicacid(DMPA)poly(butyleneadipate)(PBA)andpolypropyleneglycol(PPG).Theprepolymersareblockedwith2methoxyethanolfollowedbyneutralizationpendantcarboxylbytriethylamine(TEA)

8、thendilutedto50wt%withmethylethylketone(MEK)，emulsifiedbyaddingdeionizedwaterunderconstantagitation.Theprincipleofemulsificationisexplained.TheaggregatedstructureofprepolymersinorganicsolventisdiscussedTheprepolymermolec

9、uleswithionicgroupscanformsegmentsmicroioniclaticesTheemulsificationprocessandphaseinversionarecharacterizedbyusingthevariationofviscosityandconductivity.Theemulsificationprocessincludesthedissociationofthesegmentsmicroi

10、oniclaticesandtheaggregationofthehydrophobicsegments.Theinversionprocesscanbeclearlydividedintothreeregionsdependinguponthevariationofviscosityandconductivity.Theexperimentalresultsshowthatseveralfactorscanafectthephasei

11、nversionheavilyincludingthemolecularweightandtypeofsoftsegmentsthenrrconoeratiocarboxylcontentandneutralizationdegree.Withtheincreasingofthemolecularweightofsoftsegmentthephaseinversiondelay.Inadditionthephaseinversionof

12、PBAbasedprepolymeroccursearlythanthatofPPGbasedprepolymerwhiletheirsoftsegmentmolecularweightareequal.Highnriconoxrationotonlydecreasetheviscosityofbothprepolymersolutionandemulsificationsystembutalsomakephaseinversionoc

13、curearly.Withtheincreasingofcarboxylcontentthephaseinversionoccursearly.Inthemeantimeappropriatecarboxylcontentcandecreasetheviscosityofphaseinversionpointandleadtoeasyphaseinversion.Thedecreaseofneutralizationdegreecanc

14、ontributetolowviscosityandearlyphaseinversion.Selectingappropriateconditionscanoptimizetheemulsificationprocess.Anewtypeofhydrophilicmonomer(K600)withbothionicgroupsandnonionicsegmentswassynthesizedfrompolyethyleneoxide(

15、Mn=600)and1245benzenetetracarboxylicdianhydride(BTDA).ThesynthesisprocesswasmonitoredwithFTIR.SeveralselfemulsifiablepolyurethaneemulsionswerepreparedfromIPDIPBAandK600inaprepolymermixingprocessusingsubstantialamountsolv

16、ent.TheacidgroupsareneutralizedwithTEA.TheemulsionbasedonDMPAwaspreparedbythesameprocedureforcomparison.TheefectofK600contentonthecharacteristicsofemulsionssuchasvisualappearanceparticlesizeanddistributionviscositydurabi