Ua hoʻomākaukauʻia ka hopena hui pūʻia o ka poly-L-lactic acid a me ka ethyl cellulose i loko o ka chloroform a me ka hopena o ka PLLA a me ka methyl cellulose i loko o ka waikawa trifluoroacetic, a ua hoʻomākaukauʻia ka hui PLLA / cellulose ether ma ka hoʻoleiʻana;Ua ʻike ʻia nā huila i loaʻa e ka lau transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) a me X-ray diffraction (XRD).Aia kahi paʻa hydrogen ma waena o PLLA a me cellulose ether, a ʻokoʻa nā ʻāpana ʻelua.Me ka hoʻonui ʻana i ka ʻike o ka cellulose ether i loko o ka hui ʻana, e emi ana ka helu heheʻe, crystallinity a me ka pono aniani o ka hui ʻana.Ke ʻoi aku ka kiʻekiʻe o ka ʻike MC ma mua o 30%, hiki ke loaʻa nā huila amorphous.No laila, hiki ke hoʻohana ʻia ka cellulose ether e hoʻololi i ka poly-L-lactic acid e hoʻomākaukau ai i nā mea polymer degradable me nā waiwai like ʻole.
Hua'ōlelo: poly-L-lactic acid, ethyl cellulose,methyl cellulose, huipu ana, cellulose etera
ʻO ka hoʻomohala ʻana a me ka hoʻohana ʻana i nā polymers kūlohelohe a me nā mea polymer synthetic degradable e kōkua i ka hoʻoponopono ʻana i ka pilikia kaiapuni a me nā pilikia waiwai e kū nei nā kānaka.I nā makahiki i hala iho nei, ʻo ka noiʻi e pili ana i ka synthesis o nā mea polymer biodegradable me ka hoʻohana ʻana i nā kumuwaiwai hou e like me ka polymer raw material ua hoʻokipa nui ʻia.ʻO ka polylactic acid kekahi o nā polyesters aliphatic degradable koʻikoʻi.Hiki ke hana ʻia ka ʻakika lactic ma ka fermentation o nā mea kanu (e like me ke kulina, ʻuala, sucrose, etc.), a hiki ke hoʻopau ʻia e nā microorganism.He kumu waiwai hou ia.Hoʻomākaukau ʻia ka polylactic acid mai ka lactic acid e ka polycondensation pololei a i ʻole polymerization wehe ʻana i ke apo.ʻO ka huahana hope loa o kona hoʻohaʻahaʻa ʻana he lactic acid, ʻaʻole ia e hoʻohaumia i ke kaiapuni.Loaʻa i ka PIA nā waiwai mechanical maikaʻi loa, hiki ke hana, biodegradability a me ka biocompatibility.No laila, ʻaʻole i loaʻa i ka PLA kahi ākea ākea o nā noi ma ke kahua o ka ʻenekinia biomedical, akā loaʻa nō hoʻi nā mākeke koʻikoʻi nui i nā ʻano o ka uhi, plastics, a me nā textiles.
ʻO ke kumu kūʻai kiʻekiʻe o ka poly-L-lactic acid a me kāna mau hemahema hana e like me ka hydrophobicity a me ka brittleness e kaupalena i kāna mau noi.I mea e hōʻemi ai i kona kumukūʻai a hoʻomaikaʻi i ka hana o ka PLLA, ua aʻo hohonu ʻia ka hoʻomākaukau, hoʻohālikelike, morphology, biodegradability, mechanical properties, hydrophilic/hydrophobic balance a me nā kahua noi o nā polylactic acid copolymers a me nā huila.Ma waena o lākou, hana ʻo PLLA i kahi hui kūpono me ka poly DL-lactic acid, polyethylene oxide, polyvinyl acetate, polyethylene glycol, etc. ʻO ka cellulose kahi mea polymer kūlohelohe i hoʻokumu ʻia e ka condensation o β-glucose, a ʻo ia kekahi o nā kumuwaiwai hou loa. ma ke ano.ʻO ka cellulose derivatives nā mea polymer kūlohelohe mua loa i hoʻomohala ʻia e nā kānaka, ʻo ka mea nui o ia mau cellulose ethers a me cellulose esters.M.Nagata et al.ua aʻo i ka PLLA/cellulose blend system a ʻike ʻia ʻaʻole kūpono nā ʻāpana ʻelua, akā ua hoʻopilikia nui ʻia ka crystallization a me nā waiwai degradation o PLLA e ka mea cellulose.N.Ua aʻo ʻo Ogata et al i ka hana a me ke ʻano o ka PLLA a me ka cellulose acetate blend system.Ua aʻo pū ka patent Iapana i ka biodegradability o PLLA a me nā hui nitrocellulose.Y.Ua aʻo ʻo Teramoto et al i ka hoʻomākaukau ʻana, nā mea wela a me nā mea mechanical o PLLA a me cellulose diacetate graft copolymers.I kēia manawa, he liʻiliʻi loa nā haʻawina e pili ana i ka hui ʻana o ka polylactic acid a me ka cellulose ether.
I nā makahiki i hala iho nei, ua komo kā mākou hui i ka noiʻi ʻana i ka copolymerization pololei a me ka hoʻohui ʻana i ka hoʻololi ʻana o ka polylactic acid a me nā polymers ʻē aʻe.No ka hoʻohui ʻana i nā waiwai maikaʻi loa o ka polylactic acid me ke kumu kūʻai haʻahaʻa o cellulose a me kāna mau derivatives e hoʻomākaukau ai i nā mea polymer biodegradable piha, koho mākou i ka cellulose (ether) i mea hoʻololi no ka hoʻohui ʻana i ka hoʻololi.ʻO ka Ethyl cellulose a me ka methyl cellulose ʻelua mau ether cellulose koʻikoʻi.ʻO ka Ethyl cellulose kahi wai-insoluble non-ionic cellulose alkyl ether, hiki ke hoʻohana ʻia e like me nā mea lapaʻau, plastics, adhesives a me nā mea hoʻopau textile.ʻO ka methyl cellulose ka wai-soluble, he maikaʻi loa ka wettability, cohesiveness, ka mālama ʻana i ka wai a me nā waiwai hana kiʻiʻoniʻoni, a hoʻohana nui ʻia i nā kahua o nā mea kūkulu hale, nā uhi, nā mea hoʻonaninani, nā lāʻau lapaʻau a me ka hana pepa.Ma ʻaneʻi, ua hoʻomākaukau ʻia nā huila PLLA/EC a me PLLA/MC e ke ʻano hoʻoheheʻe ʻana, a ua kūkākūkā ʻia ke kūlike, nā waiwai wela a me nā waiwai crystallization o PLLA/cellulose ether blends.
1. Māhele hoʻokolohua
1.1 Mea maka
Ethyl cellulose (AR, Tianjin Huazhen Special Chemical Reagent Factory);methyl cellulose (MC450), sodium dihydrogen phosphate, disodium hydrogen phosphate, ethyl acetate, stannous isooctanoate, chloroform (ʻo ia nā huahana a pau o Shanghai Chemical Reagent Co., Ltd., a ʻo ka maʻemaʻe ʻo AR grade);L-lactic acid (kahi lāʻau lapaʻau, hui PURAC).
1.2 Hoʻomākaukau i nā hui
1.2.1 Hoʻomākaukau i ka waika polylactic
Ua hoʻomākaukau ʻia ka poly-L-lactic acid e ke ʻano polycondensation pololei.E kaupaona i ka wai wai L-lactic acid me ka hakina nui o 90% a e hoʻohui i loko o kahi ipu ʻāʻī ʻekolu, e hoʻomaloʻo i ka wai ma 150°C no 2 mau hola ma lalo o ke kaomi maʻamau, a laila e hana no 2 mau hola ma lalo o ke kaomi ʻana o 13300Pa, a hope loa. e hana no 4 mau hola ma lalo o kahi mānoanoa o 3900Pa e loaʻa ai kahi mea prepolymer dehydrated.ʻO ka nui o ka waiʻawaʻawaʻawaʻawaʻawaʻawaʻawaʻawa i hoʻemiʻia ka wai i hoʻopukaʻia,ʻo ia ka nui o ka prepolymer.E hoʻohui i ka stannous chloride (ʻo ka hapa nui he 0.4%) a me ka p-toluenesulfonic acid (ka lākiō o ka stannous chloride a me ka p-toluenesulfonic acid he 1/1 molar ratio) catalyst system i ka prepolymer i loaʻa, a ma ka condensation Ua hoʻokomo ʻia nā kānana Molecular i loko o ka paipu. e komo i kahi wai liʻiliʻi, a mālama ʻia ka hoʻoulu ʻana mechanical.Hoʻopili ʻia ka ʻōnaehana holoʻokoʻa ma kahi ʻāpana o 1300 Pa a me kahi mahana o 150 ° C. no 16 mau hola e loaʻa ai kahi polymer.E hoʻoheheʻe i ka polymer i loaʻa i loko o ka chloroform e hoʻomākaukau i kahi hopena 5%, kānana a hoʻoheheʻe me ka anhydrous ether no 24 mau hola, kānana i ka precipitate, a waiho i loko o ka umu -0.1MPa ma 60 ° C no 10 a 20 mau hola e loaʻa ai ka maloʻo maʻemaʻe. PLLA polimer.Ua hoʻoholo ʻia ka paona molekala pili o ka PLLA i loaʻa he 45000-58000 Daltons e ka chromatography wai kiʻekiʻe (GPC).Ua mālama ʻia nā laʻana i loko o kahi desiccator me ka phosphorus pentoxide.
1.2.2 Hoʻomākaukau ʻana o ka polylactic acid-ethyl cellulose blend (PLLA-EC)
E kaupaona i ka nui o ka poly-L-lactic acid a me ka ethyl cellulose e hana i ka solution chloroform 1% i kēlā me kēia, a laila e hoʻomākaukau i ka solution huikau PLLA-EC.ʻO ka lakio o ka PLLA-EC i hui pū ʻia: 100/0, 80/20, 60/40, 40/60, 20/80, 0/l00, ʻo ka helu mua ka hakina nui o PLLA, a ʻo ka helu hope e hōʻike ana i ka nuipaʻa o EC Fraction.Ua hoʻoulu ʻia nā mea hoʻonā i hoʻomākaukau ʻia me kahi mea hoʻonā magnetic no 1-2 mau hola, a laila ninini ʻia i loko o kahi kīʻaha aniani e hiki ai i ka chloroform ke evaporate kūlohelohe e hana i kahi kiʻiʻoniʻoni.Ma hope o ka hoʻokumu ʻia ʻana o ke kiʻiʻoniʻoni, ua waiho ʻia i loko o ka umu maloʻo e maloʻo i ka haʻahaʻa haʻahaʻa no 10 mau hola e hoʻopau loa i ka chloroform i loko o ke kiʻi..ʻAʻole waihoʻoluʻu a ʻākala ka hoʻonā hui ʻana, a ʻo ka kiʻiʻoniʻoni hui pū kekahi ʻaʻohe kala a me ka ʻike.Ua maloʻo ka hui ʻana a mālama ʻia i loko o kahi desiccator no ka hoʻohana ʻana ma hope.
1.2.3 Ka hoʻomākaukau ʻana i ka huila polylactic acid-methylcellulose (PLLA-MC)
E kaupaona i ka nui o ka poly-L-lactic acid a me ka methyl cellulose e hana ai i 1% trifluoroacetic acid solution.Ua hoʻomākaukau ʻia ke kiʻi huila PLLA-MC ma ke ʻano like me ke kiʻi hui PLLA-EC.Hoʻomaloʻo ʻia ka hui ʻana a mālama ʻia i loko o kahi desiccator no ka hoʻohana ʻana ma hope.
1.3 Hoao hana
MANMNA IR-550 infrared spectrometer (Nicolet.Corp) ana i ka infrared spectrum o ka polymer (KBr papa).DSC2901 differential scanning calorimeter (TA hui) ua hoʻohana 'ia e ana i ka DSC pihi o ka hāpana, ka wela wela o 5 ° C / min, a me ke aniani hoʻololi wela, helu hehee a me ka crystallinity o ka polymer ua ana.E hoʻohana iā Rigaku.Ua hoʻohana ʻia ka D-MAX/Rb diffractometer no ka hoʻāʻo ʻana i ke kumu hoʻohālikelike X-ray o ka polymer e aʻo ai i nā waiwai crystallization o ka hāpana.
2. Nā hopena a me ke kūkākūkā
2.1 Ka noiʻi ʻike kikoʻī infrared
Hiki i ka Fourier transform infrared spectroscopy (FT-IR) ke aʻo i ka pilina ma waena o nā ʻāpana o ka hui ʻana mai ke ʻano o ka pae mole.Inā kūpono nā homopolymers ʻelua, hoʻololi i ka alapine, hoʻololi i ka ikaika, a hiki ke ʻike ʻia ke ʻano a i ʻole ka nalo ʻana o nā piko o nā ʻāpana.Inā ʻaʻole kūpono nā homopolymers ʻelua, ʻo ke kiko o ka hui ʻana he superposition wale nō o nā homopolymers ʻelua.I loko o ka spectrum PLLA, aia kahi kiʻekiʻe haʻalulu o C=0 ma 1755cm-1, kahi piko nāwaliwali ma 2880cm-1 i hoʻokumu ʻia e ka C-H o ka haʻalulu o ka pūʻulu methine, a ʻo kahi hui ākea ma 3500 cm-1. ma muli o nā pūʻulu hydroxyl terminal.Ma ka spectrum EC, ʻo ka peak hiʻona ma 3483 cm-1 ʻo ia ka OH stretching vibration peak, e hōʻike ana aia nā pūʻulu O-H i koe ma ke kaulahao mole, ʻoiai ʻo 2876-2978 cm-1 ka C2H5 stretching vibration peak, a me 1637. ʻO ka cm-1 ʻo ia ka HOH Bending vibration peak (ma muli o ka wai hoʻoheheʻe wai).Ke hui pū ʻia ʻo PLLA me EC, ma ka IR spectrum o ka ʻāina hydroxyl o ka hui ʻana o PLLA-EC, hoʻololi ka piko O-H i haʻahaʻa haʻahaʻa haʻahaʻa me ka piʻi ʻana o ka maʻiʻo EC, a hiki i ka liʻiliʻi i ka wā PLLA / Ec he 40/60 helu hawewe, a laila hoʻololi i nā helu hawewe kiʻekiʻe, e hōʻike ana he paʻakikī ka pilina ma waena o PUA a me 0-H o EC.Ma ka ʻāpana haʻalulu C=O o 1758cm-1, ua neʻe iki ke kiʻekiʻe C=0 o PLLA-EC i ka helu haʻahaʻa haʻahaʻa me ka piʻi ʻana o EC, i hōʻike ʻia ua nāwaliwali ka pilina ma waena o C=O a me OH o EC.
Ma ka spectrogram o ka methylcellulose, ka piko hiʻona ma 3480cm-1 ka O-H kikoo vibration peak, 'o ia hoʻi, he koena O-H pūʻulu ma ka MC molecular kaulahao, a me ka HOH kulou haʻalulu peak ma 1637cm-1, a ʻoi aku ka hygroscopic o ka MC ratio EC.E like me ka PLLA-EC blend system, ma ka infrared spectra of the hydroxyl region of the PLLA-EC blend, ka O-H peak e hoololi me ka hoonui ana i ka MC content, a loaʻa ka helu hawewe haʻahaʻa i ka PLLA/MC. 70/30.Ma ka ʻāpana haʻalulu C=O (1758 cm-1), hoʻololi iki ka piko C=O i nā helu haʻahaʻa haʻahaʻa me ka hoʻohui ʻana o MC.E like me kā mākou i ʻōlelo ai ma mua, nui nā pūʻulu ma PLLA hiki ke hana i nā pilina kūikawā me nā polymers ʻē aʻe, a ʻo nā hopena o ka spectrum infrared ka hopena i hui pū ʻia o ka nui o nā pilina kūikawā.I loko o ka ʻōnaehana hui o PLLA a me cellulose ether, aia nā ʻano paʻa hydrogen like ʻole ma waena o ka pūʻulu ester o PLLA, ka pūʻulu hydroxyl terminal a me ka pūʻulu ether o cellulose ether (EC a i ʻole MG), a me nā pūʻulu hydroxyl i koe.Hiki i nā PLLA a me EC a i ʻole nā MC ke kūpono i kekahi hapa.Ma muli paha o ke ola ʻana a me ka ikaika o nā paʻa hydrogen lehulehu, no laila ʻoi aku ka nui o nā loli o ka ʻāpana O-H.Eia nō naʻe, ma muli o ke kāohi steric o ka pūʻulu cellulose, nāwaliwali ka pilina hydrogen ma waena o ka hui C=O o PLLA a me ka pūʻulu O-H o cellulose ether.
2.2 noiʻi DSC
Nā pihi DSC o PLLA, EC a me PLLA-EC hui pū.ʻO ka mahana hoʻololi aniani Tg o PLLA he 56.2°C, ʻo ka wela hoʻoheheʻe aniani Tm he 174.3°C, a ʻo ka crystallinity he 55.7%.He polimer amorphous ʻo EC me kahi Tg o 43°C a ʻaʻohe wela hoʻoheheʻe.ʻO ka Tg o nā ʻāpana ʻelua o PLLA a me EC ua kokoke loa, a ua uhi ʻia nā ʻāpana hoʻololi ʻelua a ʻaʻole hiki ke hoʻokaʻawale ʻia, no laila paʻakikī ke hoʻohana ʻana ia mea ma ke ʻano he criterion no ka pili ʻana o ka ʻōnaehana.Me ka hoʻonui ʻana o EC, ua emi iki ka Tm o ka hui ʻana o PLLA-EC, a ua emi ka crystallinity (ʻo ka crystallinity o ka hāpana me PLLA/EC 20/80 he 21.3%).Ua emi ka Tm o nā hui me ka hoʻonui ʻana o ka ʻike MC.Ke emi ka PLLA/MC ma mua o 70/30, paʻakikī ke ana ʻana o ka Tm o ka hui ʻana, ʻo ia hoʻi, hiki ke loaʻa ka hui ʻana amorphous.ʻO ka hoʻohaʻahaʻa ʻana i ka helu heheʻe o ka hui ʻana o nā polymers crystalline me nā polymers amorphous ma muli o nā kumu ʻelua, ʻo kekahi ka hopena dilution o ka mea amorphous;ʻo nā hopena hoʻolālā ʻē aʻe e like me ka hoʻemi ʻana i ka perfect crystallization a i ʻole ka nui aniani o ka polymer crystalline.Ua hōʻike nā hopena o DSC i loko o ka ʻōnaehana hui o PLLA a me cellulose ether, ʻokoʻa nā ʻāpana ʻelua, a ua kāohi ʻia ke kaʻina hana crystallization o PLLA i loko o ka hui ʻana, ka hopena o ka emi ʻana o Tm, crystallinity a me ka nui aniani o PLLA.Hōʻike kēia e ʻoi aku ka maikaʻi o ka hoʻohālikelike ʻelua o ka ʻōnaehana PLLA-MC ma mua o ka ʻōnaehana PLLA-EC.
2.3 X-ray diffraction
ʻO ka pihi XRD o PLLA ka piko ikaika loa ma 2θ o 16.64°, e pili ana i ka mokulele aniani 020, aʻo nā piko ma 2θ o 14.90°, 19.21° a me 22.45° pili me 101, 023, a me 121 mau aniani.ʻO ka ʻili, ʻo ia hoʻi, ʻo PLLA ka ʻōnaehana α-crystalline.Eia nō naʻe, ʻaʻohe kiʻekiʻe kiʻekiʻe kiʻekiʻe o ka ʻāpana ʻokoʻa o EC, e hōʻike ana he hale amorphous ia.I ka hui ʻana o PLLA me EC, ua hoʻomāhuahua ʻia ka piko ma 16.64°, nāwaliwali kona ikaika, a neʻe iki i kahi kihi haʻahaʻa.I ka 60% o ka maʻiʻo EC, ua hoʻopuehu ka piko crystallization.Hōʻike nā peaks diffraction x-ray haiki i ka crystallinity kiʻekiʻe a me ka nui o ka palaoa.ʻOi aku ka laulā o ka piko diffraction, ʻoi aku ka liʻiliʻi o ka nui o ka palaoa.ʻO ka hoʻololi ʻana o ka piko ʻokoʻa i kahi kihi haʻahaʻa e hōʻike ana i ka piʻi ʻana o ka spacing palaoa, ʻo ia hoʻi, e emi ana ka pono o ke aniani.Aia kahi paʻa hydrogen ma waena o PLLA a me Ec, a emi ka nui o ka palaoa a me ka crystallinity o PLLA, ʻo ia paha no ka mea ʻokoʻa ʻo EC me PLLA e hana i kahi ʻano amorphous, a laila e hōʻemi ana i ka pono o ke ʻano aniani o ka hui.Hōʻike pū nā hopena ʻokoʻa X-ray o PLLA-MC i nā hopena like.Hōʻike ka ʻōkuhi X-ray diffraction i ka hopena o ka ratio o PLLA/cellulose ether ma ke ʻano o ka hui ʻana, a ua kūlike nā hopena me nā hopena o FT-IR a me DSC.
3. Ka hopena
Ua aʻo ʻia ka ʻōnaehana hui o ka poly-L-lactic acid a me ka cellulose ether (ethyl cellulose a me ka methyl cellulose).Ua aʻo ʻia ka hoʻohālikelike ʻana o nā ʻāpana ʻelua i ka ʻōnaehana hui ʻia e FT-IR, XRD a me DSC.Ua hōʻike ʻia nā hopena i loaʻa ka hoʻopaʻa hydrogen ma waena o PLLA a me cellulose ether, a ʻo nā ʻāpana ʻelua i loko o ka ʻōnaehana ua kūpono kekahi.ʻO ka emi ʻana o ka ratio PLLA/cellulose ether i ka emi ʻana o ka helu heheʻe, crystallinity, a me ka pono aniani o PLLA i ka hui ʻana, ka hopena i ka hoʻomākaukau ʻana i nā huila o nā crystallinity like ʻole.No laila, hiki ke hoʻohana i ka cellulose ether e hoʻololi i ka poly-L-lactic acid, kahi e hui pū ai i ka hana maikaʻi loa o ka polylactic acid a me ke kumu kūʻai haʻahaʻa o ka cellulose ether, kahi kūpono i ka hoʻomākaukau ʻana i nā mea polymer biodegradable piha.
Ka manawa hoʻouna: Jan-13-2023