Qhov sib txawv tseem ceeb ntawm PLA thiab PLGA yog PLA yog polylactic acid, uas yog tsim los ntawm cov tshuaj tiv thaiv condensation ntawm lactic acid, whereas PLGA yog poly (lactic-co-glycolic acid), uas yog synthesized los ntawm copolymerization ntawm glycolic acid thiab lactic acid.
Ob leeg PLA thiab PLGA yog cov khoom siv polymer uas muaj qhov kub thiab txias. Txawm li cas los xij, lawv txawv ntawm ib leeg vim PLA yog tsim los ntawm ib qho monomer thaum PGLA yog tsim los ntawm ob lub monomers.
PLA yog dab tsi?
Lub sij hawm PLA sawv cev rau polylactic acid. Nws yog thermoplastic polymer peb tuaj yeem faib ua polyester. Lub cev pob txha ntawm cov khoom siv polymer no yog (C3H4O2)n. Peb tuaj yeem tsim cov polymer no los ntawm cov tshuaj tiv thaiv condensation. Cov monomer siv rau qhov kev sib txuas no yog lactic acid. Thaum lub sij hawm condensation cov tshuaj tiv thaiv ntawm lactic acid, ib tug dej molecule yog tsim thiab tso tawm. Tsis tas li, peb tuaj yeem npaj cov PLA polymer no los ntawm lub nplhaib-qhib polymerization ntawm lactide. Lactide yog cyclic dimer ntawm qhov pib rov ua dua tshiab, lactic acid.
Daim duab 01: Rov Ua Haujlwm ntawm PLA
PLA yog cov khoom siv polymer ntau vim nws yog tsim los ntawm kev lag luam los ntawm cov khoom siv txuas ntxiv. Nws muaj qhov thib ob feem ntau noj ntawm bioplastics. Txawm li cas los xij, nws tsis yog siv los ua cov khoom lag luam polymer. Kev siv ntau ntawm PLA tau cuam tshuam los ntawm qee qhov ntawm nws lub cev thiab kev ua haujlwm tsis zoo, tab sis nws yog cov khoom siv yas siv ntau tshaj plaws hauv 3D luam ntawv daim ntawv thov.
Thaum xav txog kev tsim cov PLA, peb tuaj yeem tau txais cov monomer lactic acid los ntawm fermented cov hmoov txhuv nplej siab; e.g. Cov hmoov txhuv nplej siab, pob kws hmoov nplej, qab zib, qab zib beet pulp, thiab lwm yam. Txoj kev uas feem ntau siv rau kev tsim PLA yog lub nplhaib-qhib polymerization ntawm lactide nyob rau hauv lub xub ntiag ntawm hlau catalysts nyob rau hauv ib tug tov los yog ncua kev kawm ntawv.
Lactic acid yog ib qho chiral compound. Yog li, yog tias cov polymer no yog tsim los ntawm L, L-lactide, tom qab ntawd cov khoom polymer yog PLLA (poly-L-lactide). Peb tuaj yeem soj ntsuam tias PLA yog soluble hauv cov kuab tshuaj organic xws li benzene (kub hnyav), tetrahydrofuran, dioxane, thiab lwm yam. Thaum xav txog cov khoom siv kho tshuab ntawm PLA, nws tuaj yeem muaj xws li amorphous glassy polymer mus rau semi-crystalline polymer. Qee lub sij hawm, muaj cov crystalline polymers heev.
PLGA yog dab tsi?
Lo lus PLGA sawv cev rau poly (lactic-co-glycolic) acid. Nws yog copolymer uas yog tsim los ntawm lub nplhaib-qhib copolymerization ntawm ob lub monomers sib txawv: glycolic acid thiab lactic acid. Peb tuaj yeem tsim cov polymers no ua cov polymers random los yog block copolymer. Ntxiv mus, qhov ntau lawm no yuav tsum tau catalysts xws li tin (II) 2-ethylhexanoate. Thaum lub sij hawm tus txheej txheem ntawm no copolymerization, monomer units yuav txuas ib leeg ntawm ester bonds, yielding ib tug linear, aliphatic polyester polymer khoom.
Tsis tas li ntawd, nws muaj peev xwm tau txais ntau hom PLGA thaum peb siv cov khoom sib txawv ntawm cov monomer. Cov ntaub ntawv sib txawv no tau txhais raws li cov molar piv ntawm cov monomers siv rau txheej txheem polymerization. Ntxiv rau cov no, PLGA tuaj yeem sib txawv los ntawm tag nrho amorphous mus rau tag nrho cov qauv crystalline raws li cov qauv thaiv thiab cov molar piv ntawm cov polymer.
Daim duab 02: Rov ua dua Chav ntawm PLGA
Thaum xav txog qhov degradation ntawm PLGA, nws degrades ntawm hydrolysis ntawm nws ester linkages nyob rau hauv lub xub ntiag ntawm dej. Lub sij hawm uas yuav tsum tau rau qhov degradation ntawm PLGA nyob ntawm tus monomer piv uas yog siv rau nws cov khoom.
Qhov txawv ntawm PLA thiab PLGA yog dab tsi?
PLA thiab PGLA yog cov khoom siv thermoplastic polymer. Qhov sib txawv tseem ceeb ntawm PLA thiab PLGA yog PLA yog polylactic acid uas yog tsim los ntawm condensation cov tshuaj tiv thaiv ntawm lactic acid whereas PLGA yog poly (lactic-co-glycolic acid) uas yog synthesized ntawm copolymerization ntawm glycolic acid thiab lactic acid.
Hauv qab infographic tabulates qhov sib txawv ntawm PLA thiab PLGA kom ntxaws ntxiv.
Summary – PLA vs PLGA
Lub sij hawm PLA sawv cev rau polylactic acid thaum lub sij hawm PLGA sawv cev rau poly (lactic-co-glycolic) acid. Qhov sib txawv tseem ceeb ntawm PLA thiab PLGA yog PLA yog polylactic acid uas yog synthesized los ntawm condensation cov tshuaj tiv thaiv ntawm lactic acid whereas PGLA yog poly (lactic-co-glycolic acid) uas yog synthesized ntawm copolymerization ntawm glycolic acid thiab lactic acid.
