Harateguwe igisubizo kivanze na aside poly-L-lactique na Ethyl selulose muri chloroform hamwe nigisubizo kivanze cya PLLA na methyl selulose muri acide trifluoroacetic, hanyuma ivangwa rya PLLA / selulose ether ryateguwe no guta; Ibivanze byabonetse byaranzwe no guhindura amababi ya infrarafurike ya spekitroscopi (FT-IR), itandukanyirizo rya scanning calorimetry (DSC) na X-ray itandukanya (XRD). Hano hari hydrogen ihuza PLLA na selile ether, kandi ibice byombi birahuza igice. Hamwe no kwiyongera kwa selile ether yibintu bivanze, aho gushonga, kristu hamwe nuburinganire bwa kirisiti byose bizagabanuka. Iyo ibirimo MC birenze 30%, hafi ya amorphous ivanze irashobora kuboneka. Kubwibyo, selile ya selile irashobora gukoreshwa muguhindura aside poly-L-lactique kugirango itegure ibikoresho bya polymer byangirika nibintu bitandukanye.
Ijambo ryibanze: aside poly-L-lactique, selile ya Ethyl,methyl selulose, kuvanga, selile ya ether
Gutezimbere no gukoresha polymers karemano nibikoresho byangirika bya polymer bizafasha gukemura ikibazo cyibidukikije nibibazo byumutungo abantu bahura nabyo. Mu myaka ya vuba aha, ubushakashatsi bwakozwe kuri synthesis yibikoresho bya polymer biodegradable hifashishijwe ibikoresho bishobora kuvugururwa nkibikoresho fatizo bya polymer byashimishije abantu benshi. Acide Polylactique nimwe mubintu byingenzi byangirika bya alifatique polyester. Acide lactique irashobora kubyara fermentation yibihingwa (nkibigori, ibirayi, sucrose, nibindi), kandi birashobora no kubora na mikorobe. Nibikoresho bishobora kuvugururwa. Acide polylactique itegurwa na acide lactique na polycondensation itaziguye cyangwa gufungura polymerisation. Ibicuruzwa byanyuma byo kwangirika kwayo ni aside ya lactique, itazanduza ibidukikije. PIA ifite imiterere myiza yubukanishi, itunganijwe, ibinyabuzima bigabanuka hamwe na biocompatibilité. Kubera iyo mpamvu, PLA ntabwo ifite gusa porogaramu nini mu bijyanye n’ubuhanga bw’ibinyabuzima, ariko ifite n’amasoko manini ashobora kuba mu bijyanye n’imyenda, plastiki, n’imyenda.
Igiciro kinini cya acide poly-L-lactique hamwe nubusembwa bwayo nka hydrophobicity na brittleness bigabanya aho ikoreshwa. Mu rwego rwo kugabanya igiciro cyacyo no kunoza imikorere ya PLLA, gutegura, guhuza, morphologie, ibinyabuzima bigabanuka, imiterere yubukanishi, hydrophilique / hydrophobique iringaniza hamwe nimirima ikoreshwa na polylactique acide kopolymers hamwe nuruvange byizwe cyane. Muri byo, PLLA ikora uruvange ruhuza aside DL-lactique, okiside polyethylene, polyetinile acetate, polyethylene glycol, nibindi. muri kamere. Ibikomoka kuri selile ni ibikoresho bya kera bya polymer bisanzwe byakozwe n'abantu, icy'ingenzi muri byo ni selile ya selile na estul selile. M． Nagata n'abandi. yize sisitemu yo kuvanga PLLA / selile isanga ibyo bice byombi bidahuye, ariko ibintu byo korohereza no gutesha agaciro PLLA byagize ingaruka cyane kubigize selile. N． Ogata nabandi bize imikorere n'imiterere ya PLLA na selile ya acetate ya selile. Ipatanti y'Ubuyapani yize kandi ku binyabuzima bya PLLA na nitrocellulose. Y． Teramoto nabandi bize imyiteguro, ubushyuhe nubukanishi bwa PLLA na selile ya diacetate graft copolymers. Kugeza ubu, hari ubushakashatsi buke cyane kuri sisitemu yo kuvanga aside polylactique na selile ya ether.
Mu myaka yashize, itsinda ryacu ryagize uruhare mubushakashatsi bwa copolymerisation itaziguye no kuvanga ihinduka rya aside polylactique nizindi polymers. Kugirango duhuze ibintu byiza bya acide polylactique hamwe nigiciro gito cya selile hamwe nibiyikomokaho kugirango dutegure ibikoresho bya polymer biodegradable byuzuye, duhitamo selile (ether) nkibintu byahinduwe kugirango bivange. Ethyl selulose na methyl selulose nibintu bibiri byingenzi bya selile. Ethyl selulose ni amazi adashobora gushonga non-ionic selulose alkyl ether, ishobora gukoreshwa nkibikoresho byubuvuzi, plastiki, ibifunga hamwe nibikoresho byo kurangiza imyenda. Methyl selulose irashobora gushonga amazi, ifite ubushuhe buhebuje, guhuriza hamwe, gufata amazi hamwe no gukora firime, kandi ikoreshwa cyane mubijyanye nibikoresho byubaka, gutwikira, kwisiga, imiti no gukora impapuro. Hano, imvange ya PLLA / EC na PLLA / MC yateguwe hakoreshejwe uburyo bwo guta igisubizo, kandi haraganiriweho guhuza, imiterere yumuriro hamwe na kristalisiti ya PLLA / selile ya ether.
1. Igice cyubushakashatsi
1.1 Ibikoresho bibisi
Ethyl selulose (AR, Tianjin Huazhen Uruganda rwihariye rwa Shimi); methyl selulose (MC450), fosifate ya sodium dihydrogen, fosifori ya disodium hydrogène, Ethyl acetate, isooctanoate idasanzwe, chloroform (ibyavuzwe haruguru byose ni ibicuruzwa bya Shanghai Chemical Reagent Co., Ltd., kandi ubuziranenge ni urwego rwa AR); Acide L-lactique (urwego rwa farumasi, uruganda rwa PURAC).
1.2 Gutegura imvange
1.2.1 Gutegura aside polylactique
Acide Poly-L-lactique yateguwe nuburyo butaziguye bwa polycondensation. Gupima L-lactique acide yamazi hamwe nigice kinini cya 90% hanyuma ukayongeramo flask yamajosi atatu, dehidrate kuri 150 ° C mumasaha 2 munsi yumuvuduko usanzwe, hanyuma ukore amasaha 2 munsi yumuvuduko wa vacu 13300Pa, hanyuma amaherezo reba amasaha 4 munsi yicyuho cya 3900Pa kugirango ubone ibintu bya prepolymer idafite umwuma. Umubare wuzuye wa acide lactique aqueous ukuyemo amazi ukuyemo amazi ni igiteranyo cya prepolymer. Ongeramo chloride stannous (igice kinini ni 0.4%) na p-toluenesulfonic aside (igipimo cya chloride stannous na p-toluenesulfonic ni 1/1 molar ratio) sisitemu ya catalizator muri prepolymer yabonetse, naho muri kondegene hashyizwemo amashanyarazi ya molekile. gukuramo amazi make, kandi gukanika imashini byakomeje. Sisitemu yose yakiriwe ku cyuho cya 1300 Pa n'ubushyuhe bwa 150 ° C. mu masaha 16 kugirango ibone polymer. Kuramo polymer wabonye muri chloroform kugirango utegure igisubizo cya 5%, uyungurure kandi ugwe hamwe na ether ya anhydrous mumasaha 24, uyungurure imvura, hanyuma ubishyire mu ziko -0.1MPa vacuum kuri 60 ° C mumasaha 10 kugeza kuri 20 kugirango ubone byumye Polimeri. Uburemere bugereranije bwa molekulari ya PLLA yabonetse yiyemeje kuba 45000-58000 Daltons na chromatografiya ikora cyane (GPC). Ingero zabitswe muri desiccator irimo fosifore pentoxide.
1.2.2 Gutegura aside polylactique-Ethyl selulose ivanze (PLLA-EC)
Gupima urugero rukenewe rwa acide poly-L-lactique na Ethyl selulose kugirango ukore igisubizo cya chloroform 1%, hanyuma utegure igisubizo kivanze cya PLLA-EC. Ikigereranyo cya PLLA-EC igisubizo kivanze ni: 100/0, 80/20, 60/40, 40/60, 20/80, 0 / l00, umubare wambere ugereranya igice kinini cya PLLA, naho umubare wanyuma ugereranya u misa ya EC Igice. Ibisubizo byateguwe byavanze na magnetiki ya firimu mugihe cyamasaha 1-2, hanyuma bisukwa mumasahani yikirahure kugirango chloroform ihinduke muburyo busanzwe kugirango ikore firime. Filime imaze gushingwa, yashyizwe mu ziko rya vacuum kugirango yumuke ku bushyuhe buke mu masaha 10 kugirango ikure burundu chloroform muri firime. . Igisubizo kivanze ntigifite ibara kandi kibonerana, kandi firime ivanze nayo idafite ibara kandi iragaragara. Uruvange rwumye kandi rubikwa muri desiccator kugirango ruzakoreshwe nyuma.
1.2.3 Gutegura aside polylactique-methylcellulose ivanze (PLLA-MC)
Gupima urugero rukenewe rwa acide poly-L-lactique na methyl selulose kugirango ukore 1% trifluoroacetic acide. Filime ya PLLA-MC yateguwe nuburyo bumwe na firime ya PLLA-EC. Uruvange rwumye kandi rubikwa muri desiccator kugirango ruzakoreshwe nyuma.
1.3 Ikizamini cyimikorere
MANMNA IR-550 infrared spectrometer (Nicolet.Corp) yapimye infrarafarike ya polymer (tablet ya KBr). DSC2901 itandukanya scanning calorimeter (isosiyete TA) yakoreshejwe mugupima umurongo wa DSC wikitegererezo, igipimo cyo gushyuha cyari 5 ° C / min, kandi ubushyuhe bwinzibacyuho yikirahure, aho gushonga hamwe na kristu ya polymer byapimwe. Koresha Rigaku. D-MAX / Rb diffractometer yakoreshejwe mugupima imiterere ya X-ray itandukanya polymer kugirango yige imiterere ya kristu.
2. Ibisubizo n'ibiganiro
2.1 Ubushakashatsi butagira ingano
Fourier ihindura infragre spekitroscopi (FT-IR) irashobora kwiga imikoranire hagati yibigize uruvange uhereye kurwego rwa molekile. Niba abahuje ibitsina bombi bahujwe, guhinduranya inshuro, guhinduka mubukomere, ndetse no kugaragara cyangwa kubura impinga ziranga ibice bishobora kugaragara. Niba abahuje ibitsina bombi badahuje, urwego rwuruvange ni superpression ya ba homopolymers bombi. Mubice bya PLLA, hari impagarike irambuye ya C = 0 kuri 1755cm-1, impinga idakomeye kuri 2880cm-1 iterwa na C - H irambuye ihindagurika ryitsinda rya methine, naho umurongo mugari kuri cm 3500 cm-1 ni byatewe na terefone hydroxyl. Mubice bya EC, impinga iranga kuri cm 3483 cm-1 ni OH irambuye hejuru yinyeganyeza, byerekana ko hari amatsinda ya O - H asigaye kumurongo wa molekile, mugihe cm 2876-2978 cm-1 ari C2H5 irambuye hejuru yinyeganyeza, na 1637 cm-1 ni HOH Bending vibration peak (iterwa nicyitegererezo gikurura amazi). Iyo PLLA ivanze na EC, mumurongo wa IR mukarere ka hydroxyl mukarere ka PLLA-EC, impinga ya O - H ihinduka kuri wavenumber nkeya hamwe no kwiyongera kwa EC, kandi ikagera byibuze mugihe PLLA / Ec ari 40/60 wavenumber, hanyuma yimurirwa kuri wavenumbers yo hejuru, byerekana ko imikoranire hagati ya PUA na 0-H ya EC igoye. Mu karere ka C = O kunyeganyega ka 1758cm-1, impinga ya C = 0 ya PLLA-EC yimutse gato ku mubare muto w’umuvuduko wo hasi hamwe no kwiyongera kwa EC, byerekanaga ko imikoranire hagati ya C = O na OH ya EC yari ifite intege nke.
Muri spekrogramu ya methylcellulose, impinga iranga kuri 3480cm-1 ni O - H irambuye impagarike yo kunyeganyega, ni ukuvuga ko hari amatsinda O-H asigaye ku ruhererekane rwa MC, naho HOH yunamye hejuru ya 1637cm-1, na MC igereranyo EC ni hygroscopique. Kimwe na sisitemu yo kuvanga PLLA-EC, muri infragre ya ecran ya hydroxyl yo mukarere ka PLLA-EC, impinga ya O - H ihinduka hamwe no kwiyongera kwibirimo bya MC, kandi ifite numero ntarengwa yumurongo mugihe PLLA / MC ari 70/30. Mu karere ka C = O kunyeganyega (1758 cm-1), impinga ya C = O ihinduka gato kuri wavenumbers yo hepfo hiyongereyeho MC. Nkuko twabivuze mbere, hari amatsinda menshi muri PLLA ashobora gukora imikoranire idasanzwe nizindi polymers, kandi ibisubizo bya infragre spracre bishobora kuba ingaruka zifatika zidasanzwe zishoboka. Muri sisitemu yo kuvanga PLLA na selulose ether, hashobora kubaho uburyo butandukanye bwa hydrogène ihuza hagati ya ester itsinda rya PLLA, hydroxyl ya terminal hamwe na ether ya selile ya ether (EC cyangwa MG), hamwe na hydroxyl isigaye. PLLA na EC cyangwa MCs birashobora guhuzwa igice. Bishobora guterwa no kubaho n'imbaraga za hydrogène nyinshi, bityo impinduka mukarere ka O - H zirahambaye. Ariko, kubera inzitizi zikomeye zitsinda rya selile, isano ya hydrogène iri hagati ya C = O ya PLLA nitsinda O - H rya selile ether rifite intege nke.
2.2 Ubushakashatsi bwa DSC
Imirongo ya DSC ya PLLA, EC na PLLA-EC ivanze. Ubushyuhe bwikirahure Tg ya PLLA ni 56.2 ° C, ubushyuhe bwo gushonga bwa kirisiti Tm ni 174.3 ° C, naho kristu ni 55.7%. EC ni polymer amorphous ifite Tg ya 43 ° C kandi nta bushyuhe bwo gushonga. Tg yibice bibiri bigize PLLA na EC biregeranye cyane, kandi uturere twombi twinzibacyuho turuzuzanya kandi ntidushobora gutandukanywa, biragoye rero kuyikoresha nkigipimo cyo guhuza sisitemu. Ubwiyongere bwa EC, Tm ya PLLA-EC ivanze yagabanutseho gato, kandi kristu yagabanutse (kristalitike yicyitegererezo hamwe na PLLA / EC 20/80 yari 21.3%). Tm yo kuvanga yagabanutse hamwe no kwiyongera kwa MC. Iyo PLLA / MC iri munsi ya 70/30, Tm yuruvange biragoye kubipima, ni ukuvuga hafi ya amorphous ivanze irashobora kuboneka. Kugabanuka kw'ikibanza cyo gushonga kivanze na kristaline polymers hamwe na amorphous polymers mubisanzwe biterwa nimpamvu ebyiri, imwe ningaruka zo kugabanya ibice bya amorphous; izindi zishobora kuba ingaruka zubaka nko kugabanuka kwa kristu itunganijwe cyangwa ingano ya kristu ya polymer. Ibisubizo bya DSC byagaragaje ko muri sisitemu yo kuvanga PLLA na selile ya ether, ibyo bice byombi byari bihujwe igice, kandi uburyo bwo gutegera kwa PLLA muvanga bwarahagaritswe, bituma igabanuka rya Tm, kristu n’ubunini bwa kristu ya PLLA. Ibi birerekana ko ibice bibiri bigize sisitemu ya PLLA-MC bishobora kuba byiza kuruta ibya sisitemu ya PLLA-EC.
2.3 Gutandukanya X-ray
Umurongo wa XRD wa PLLA ufite impinga ikomeye kuri 2θ ya 16.64 °, ibyo bikaba bihuye nindege ya kristu 020, mugihe impinga ya 2θ ya 14.90 °, 19.21 ° na 22.45 ° ihwanye na 101, 023, na 121 kristu. Ubuso, ni ukuvuga, PLLA ni α-kristalline. Ariko, ntamiterere ya kirisiti ihanitse mugutandukanya umurongo wa EC, byerekana ko ari imiterere ya amorphous. Iyo PLLA ivanze na EC, impinga ya 16,64 ° yagutse buhoro buhoro, ubukana bwayo bwaragabanutse, kandi bwimuka gato bugana ku mfuruka yo hepfo. Iyo ibiri muri EC byari 60%, impinga ya kristu yari yatatanye. Impanuka ya x-ray itandukanya impagarike yerekana kristu nini nubunini bunini. Mugihe kinini cyo gutandukanya impinga, ingano ingano. Guhinduranya impinga ya diffaction kumpande ntoya yerekana ko intera yintete yiyongera, ni ukuvuga, ubusugire bwa kristu bugabanuka. Hariho hydrogene ihuza PLLA na Ec, kandi ingano yingano hamwe na kristu ya PLLA bigabanuka, ibyo bikaba biterwa nuko EC ihuza igice na PLLA kugirango ikore amorphous, bityo bigabanye ubusugire bwimiterere ya kristu yuruvange. Ibisubizo bya X-ray bitandukanya PLLA-MC nabyo byerekana ibisubizo bisa. Imirasire ya X-ray yerekana ingaruka zigereranyo cya PLLA / selile ya ether kumiterere yuruvange, kandi ibisubizo birahuye rwose nibisubizo bya FT-IR na DSC.
3. Umwanzuro
Sisitemu yo kuvanga aside poly-L-lactique na selulose ether (ethyl selulose na methyl selulose) yize hano. Guhuza ibice bibiri muri sisitemu yo kuvanga byizwe hakoreshejwe FT-IR, XRD na DSC. Ibisubizo byerekanaga ko guhuza hydrogène byabayeho hagati ya PLLA na selile ether, kandi ibice bibiri muri sisitemu byari bihuje igice. Igabanuka ryikigereranyo cya PLLA / selulose ether itera kugabanuka kumwanya wo gushonga, kristu, hamwe nuburinganire bwa kristu ya PLLA muruvange, bikavamo gutegura imvange ya kristu zitandukanye. Kubwibyo, selile ether irashobora gukoreshwa muguhindura aside poly-L-lactique, izahuza imikorere myiza ya acide polylactique hamwe nigiciro gito cya selile ya ether, ifasha mugutegura ibikoresho bya polymer byuzuye biodegradable.
Igihe cyo kohereza: Mutarama-13-2023