星形聚d，l乳酸的合成研究

1、重慶大學(xué)碩士學(xué)位論文星形聚D，L乳酸的合成研究姓名：余美玲申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：生物化工指導(dǎo)教師：張立武20090531重慶人學(xué)碩士學(xué)位論文英文摘要ABSTRACTPolylacticacidisbiode黟adableaIldthepolymersynthesizedbyreIlewablerawmat甜als，c觚beafhnd撇entalsoI“ontothe”whitepollution”andnleincreasingd印l

2、etionofoilresourcesComparcdwithlinearp01ylIlers，star—shapedp01yIIlershaVelowercrystallinit)r，meltViscosi饑molecularsurfacehaVeahighcrfhctionality，smallersize鋤domerpropertiesoffluiddyn鋤icsTherefore，weca|lobtainallighermole

3、cularweightiIltlleIowerViscosityatthes鋤etime，suchapolylacticacidcopolylIlercanf撕litateproduction髓dprocessingItisnecessarytesearchaIlddeVelopesimpleprocess，goodsolubilitylow—costaJldmorepracticalValueofthesta葉shapcdPolyla

4、cticacidFi咄1inearp01yD，L1acticacid(LPDLLA)wassyntheSizedbydirectlymeltp01ycondellsation盤omD，L—lacticacidItw嬲f(shuō)oundtllatmeappropriatereactionconditio邶arc弱f01lows：O5叭％ofSnCl22H20／TSAcatalyst，polym甜zationt鋤peran鵬ofl65℃，31【Pa

5、at18hSt小sh印edpolyD，Llacticacid(SPDLLA)waSs)，11t11esizedbydirectlymeltpolycondensationf硒mD，L一1acticacidusingpentaery螄tol粥acorcWhenmemolarratioofD，L一1a以cacid／pentae聊嘶tolis1000，st小shapcdSPDLLAwimt11ehi曲erspeci丘cViscosityabo

6、ut0556dL岔‘w嬲suCcess如llys)，IlmesizedButmepolymerizationtimeisshorteIledto12hourShlmes鋤emolecularweigllt，嬲tlledyn鋤icVol啪eofmestarshapedp01)，IIlerislowermaIlmelinearpolymer，tllemolecularweightofstarsh印edpolymerissi鰣ficantly

7、伊eater廿l粕melinearp01ymerinthes鋤especi矗cviscosit)，h1mes鋤ereactionconditions，mespeci丘cViscos時(shí)oflinearpolylacticacidwaslowerthaIltllatofstar—shapedpolylactide，iIldicatingmataddingasmall鋤ountofpentaeryttoltopolycondensationi

8、s觚e仃ectiVewaytosynthesizelli曲ermolecularweightofp01ylacticacidn喲u曲NMR觚alysis，indicatingnlatthehydroxylpe觚I叫l(wèi)lrit01havebeellinvolvedinthecondensationreactionwimtllelacticacidtofo咖afour猢SPDLLAUsinggelpeHneationdhromatograp

9、hy(GPC)detenninemolecularweightofSPDLLA，maxim啪weightaVeragemolecularweigllt(朋rw)=51408，men啪beraveragemoIecularweight@徹)=37250，polydisperSityindex(^fw／^徹)=137^舢／^徹islessm鋤15～2isoneoftheimportaIlts皿b01sfoI。obtainedpolymeri