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1、中文摘要本文對(duì)聚乙二醇單甲醚(mPEG)接枝殼聚糖進(jìn)行了研究。通過(guò)官能團(tuán)偶聯(lián)反應(yīng)將醛基化的聚乙二醇單甲醚接枝到不同分子量殼聚糖上,制得了梳形可分散于水的聚乙二醇單甲醚接枝殼聚糖(cS—g-mPEG),并對(duì)CS—g-mPEG的流變性、聚電解質(zhì)性質(zhì)進(jìn)行了研究。采用紅外光譜口TIR)、核磁共振(1H-NMR)、X-射線衍射(XRD)、差示掃描量熱(DSC)、熱失重(Tu)對(duì)cs.g-mPEG的結(jié)構(gòu)和性能進(jìn)行了表征。結(jié)果表明,聚乙二醇單甲醚與殼聚糖發(fā)生了接枝反應(yīng),CS.g—mPEG表現(xiàn)出不同于殼聚糖的性質(zhì)。用三聚磷酸鈉(TPP)與聚乙二醇單甲醚接枝殼聚糖通過(guò)離子凝膠法制得了亞微米粒,采用激光粒度儀
2、和透射電鏡對(duì)亞微米粒進(jìn)行了表征。結(jié)果表明,所制得的亞微米粒粒徑在100.800llln之間,呈現(xiàn)球形結(jié)構(gòu)。本文還通過(guò)氧化還原引發(fā)劑硝酸鈰銨(c舢∞引發(fā)殼聚糖主鏈開(kāi)環(huán),與聚乙二醇單甲醚甲基丙烯酸酯(mPEGMA)進(jìn)行自由基接枝,制得了聚乙二醇單甲醚甲基丙烯酸酯接枝殼聚糖(cs.g-mPEGMA)??疾榱朔磻?yīng)溫度、反應(yīng)時(shí)間、引發(fā)劑濃度、單體濃度對(duì)接枝率和接枝效率的影響。采用紅外光譜對(duì)cs.g.mPEGMA進(jìn)行了表征,并對(duì)CS.g-mPEGMA的溶液性質(zhì)進(jìn)行了初步探討。結(jié)果表明,這種方法可以將聚乙二醇單甲醚接枝到殼聚糖上,但接枝度較低。此外,本文還用碘甲烷將聚乙二醇單甲醚碘化后,在氧化銀催化下與
3、鄰苯二甲酸酐保護(hù)的殼聚糖反應(yīng),經(jīng)水合聯(lián)氨還原脫除鄰苯二甲酸基團(tuán)后制得了羥基接枝的聚乙二醇單甲醚接枝殼聚糖(cs.O-mPEG)。采用紅外光譜對(duì)Cs-O.mPEG結(jié)構(gòu)進(jìn)行了表征,結(jié)果表明聚乙二醇單甲醚確實(shí)接枝到了殼聚糖上,但是由于聚乙二醇單甲醚碘化度較低以及接枝反應(yīng)時(shí)催化劑的非均相催化使得接枝度低,具體工藝還有待于進(jìn)一步研究。關(guān)鍵詞;殼聚糖;聚乙二醇單甲醚;接枝反應(yīng);亞微米粒ABSTRACTThisthesisstudiedthegraftreactionbetweenmethoxypoly(ethyleneglyc01)(mPEG)andchitosan,andthepropertieso
4、fMethoxypoly(ethyleneglyc01)graftedchitosan(cs—g—mPEG).CS—g—mPEGsampleswimdifferentgraftdegreewerepreparedbythereactionofaldehyhydedmethoxypoly(ethyleneglyc01)and2-aminofunctionsofchitosan.Thecomb—s11apedCS—g-mPEGCanbedispersedinwater.TheirstructuresandpropertieswerecharacterizedbYFTm,1H-NMR,XRD,D
5、SCandTGTherheologlcalpropertiesofCS·g-mPEGwerestudiedbyUbbelohdeviscometer.CS—g-mPEGshowsdifferentpeopertiesfromchitosamSub-micropartieleswerepreparedbyCS-g-mPEGandtripolyphosphatethroughionizegelation.ThediameterandmorphologyweremeasuredbyBI·90PlusparticlesizeanalyzerandTEMrespectively.Theresults
6、indicatethatallthesub—microparticlespresentspherestructureswithdiametersbetween100nlTIand800am.Methoxypoly(ethyleneglyc01)methacrylate(mPEGMA)酎afIedchitosan(cs—g-mPEGMA)werepreparedbythereactionoftheVivylgroupsofmPEGMA謝thfreeradicalsonchitosanmainbonesinitiatedbyeerieammoniumnitrate(CAN).Theinflue
7、ncesofreactiontime,reactiontemperature,concentrationofCANandmPEGMAonthegraftdegreeandgraftefficiencywerestudied.ThestructureofCS-g-mPEGMAWascharacterizedbyFTIR,andtheirsolutionpropertieswerestudied.Theresultsindi