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1、l。海交通入學(xué)博上后出站報告摘要聚苯并噫唑(PBO)是一類芳香族溶致性液晶高分子,¨_
2、丁獨(dú)特的剛性結(jié)構(gòu),使其具有優(yōu)異的性能,是訖今為Ir強(qiáng)度和模量最高的合成纖維.在很多高精尖領(lǐng)域有著廣泛的用途。本文以以間苯一酚為原料,通過兩種方法制備PBO單體4,6一:氮基問苯二酚鹽酸鹽(DAR.HCI)。方法一是通過五步反應(yīng),即酯化、Fries重排、腑化、Beckmann重排、水解,得到單體4,6二氦基間苯_二酚鹽酸鹽(DAR.HCI),方法:是通過磺化、硝化、水解、還原四步反應(yīng)制備出單體4,6一二氨基間苯二酚鹽酸鹽(DAR.HCI)單體,并用
3、FTIR、MS、元素分析、1HNMR和”CNMR等對DAR,HCl及中間體進(jìn)行了表征,結(jié)果表明.單體4.6一二氨基間苯一酚鹽酸鹽(DAR.HCI)純度高,已經(jīng)達(dá)到聚合級。在合成出高純度聚合級單體的基礎(chǔ)上,本文研究了PBO的聚合反應(yīng)。與傳統(tǒng)【:豈不同,本文首先將DAR.tlCl和對苯~二甲酸(TA)制備出4,6一一二氨基間苯二酚一對苯二甲酸復(fù)合鹽(DAR/TPA),然后,以多聚磷酸為反應(yīng)介質(zhì),進(jìn)行縮聚得到了特性粘度為24.5dl/g的PBO,這樣省去了傳統(tǒng)聚合中4,6一二氨基問苯二酚鹽酸鹽(DAR.HCI)脫鹽酸的過程,大大地縮短了反
4、應(yīng)時間,保證了兩單體DAR和TA等當(dāng)暈比聚合,避免了由3-DAR過量而出現(xiàn)的分子量小的現(xiàn)象。H
5、FTIR、MS、DSC和元素分析等對TPA結(jié)構(gòu)進(jìn)行r表征,并通過傅立:葉變換紅外光譜分析(FT-IR)、紫外一可見光譜分析、喇曼散射光譜分析、”C同體核磁共振分析和熱重分析等手段對PBO的結(jié)構(gòu)和熱性能進(jìn)行研究。if{I}交通大學(xué)博l一后出站報告AbstractPolybenzoxazole(PBO)isaclassofaromaticheterocycBerigid10dpolymerswithexcellentthermalstabil
6、ity,highmechanicalproperties(tensiIestrengthandmodulus)andgoodchemicalresistance,whichmakethemhighpotentialapplicationinmanyfieldsInthispaper,wedirectedoureffortstowardsthesynthesisofPBOanditsmonomer4,6一diaminoresorcinoldjhydrochloride(DAR.HCI).Twonovelsyntheticroutesf
7、oxthesynthesisof4,6一diaminoresorcinoldihydrochloride(DARHCI)wereadoptedusingresorcinolasrawmaterialsThefirstmethodcomprisesfivestepsincludingacylatingreaction,friesrearrangement,oximation,Beckmannrearrangementandhydrolysisreaction.Thesecondmethodinvolvesfourstepsinclud
8、ingsulfonation,nitratingreaction,hydrolysisreactionandreduction.Thestructuresof4,6-diaminoresorcinoldihydrochloride(DAR.HCl)anditsintermediateproductswerecharacterizedandconfirmedbyFTIR,MS,elementalanalysis,’HNMRand”CNMRetc,whichshowsthattheproducts4,6一diaminoresorcino
9、ldihydrochloride(DARHCI)frombothofmethodshavehighpuritywithhighyield.Basedonthesuccessfulsynthesisof4,6一diaminoresorcinoldihydiochloride,thesaltofPBO4,6一diaminoresorcinol/terephthalate(DAR/TPA)Waspreparedfrom4,6·diaminoresorcinoldihydrochlorideandterephtha]icacid,which
10、wascharacterizedbyFTIRspectroscopy,MS,DSCaswellaselementalanalysis.Poly(p-phenylenebenzobisoxazole)(PBO)wasthenprepar