I-hydroxypropyl methylcelluloseluhlobo lwe-non-ionic cellulose mixed ether. Ngokungafaniyo ne-ionic methyl carboxymethyl cellulose mixed ether, ayisebenzi neentsimbi ezinzima. Ngenxa yemilinganiselo eyahlukeneyo yomxholo we-methoxyl kunye nomxholo we-hydroxypropyl kwi-hydroxypropyl methylcellulose kunye ne-viscosities ezahlukeneyo, kukho iintlobo ezininzi ezineempawu ezahlukeneyo, umzekelo, umxholo ophezulu we-methoxyl kunye nomxholo ophantsi we-hydroxypropyl Ukusebenza kwayo kusondele kwe-methyl cellulose, ngelixa ukusebenza komxholo ophantsi we-methoxyl kunye nomxholo ophezulu we-hydroxypropyl kusondele kwe-hydroxypropyl methyl cellulose. Nangona kunjalo, kuhlobo ngalunye, nangona kukho inani elincinci le-hydroxypropyl okanye inani elincinci leqela le-methoxyl, kukho umahluko omkhulu ekunyibilikeni kwi-organic solvents okanye kubushushu be-flocculation kwizisombululo zamanzi.
(1) Iipropati zokunyibilika kwe-hydroxypropyl methylcellulose
① Ukunyibilika kwe-hydroxypropyl methylcellulose emanziniI-hydroxypropyl methylcelluloseNgokwenene luhlobo lwe-methylcellulose oluguqulwe yi-propylene oxide (i-methoxy-propylene), ngoko ke iseneempawu ezifanayo ne-methyl cellulose ineempawu ezifanayo zokunyibilika kwamanzi abandayo kunye nokunganyibiliki kwamanzi ashushu. Nangona kunjalo, ngenxa yeqela le-hydroxypropyl eliguquliweyo, ubushushu bayo be-gelation emanzini ashushu buphezulu kakhulu kunobo be-methyl cellulose. Umzekelo, i-viscosity yesisombululo samanzi se-hydroxypropyl methylcellulose esine-2% methoxy content substitution degree DS=0.73 kunye nomxholo we-hydroxypropyl MS=0.46 yi-500 mpa·s kwi-20°C, kwaye ubushushu bayo be-gel bunokufikelela kufutshane ne-100°C, ngelixa i-methyl cellulose kubushushu obufanayo imalunga ne-55°C kuphela. Ngokuphathelele ukunyibilika kwayo emanzini, ikwaphuculwe kakhulu. Umzekelo, i-hydroxypropyl methylcellulose ecoliweyo (emilo yegranular 0.2 ~ 0.5mm kwi-20°C ene-4% yesisombululo samanzi esinobumanzi se-2pa•s ingathengwa kubushushu begumbi, inyibilika lula emanzini ngaphandle kokupholisa.
② Ukunyibilika kwe-hydroxypropyl methylcellulose kwizinyibilikisi zendalo, ukunyibilika kwe-hydroxypropyl methylcellulose kwizinyibilikisi zendalo kukwangcono kunokwe-methylcellulose. I-Methylcellulose kufuneka ibe ne-methoxyl substitution degree ye-2.1. Iimveliso ezingentla, kodwa eziqulethe i-hydroxypropyl MS=1.5~1.8 kunye ne-methoxy DS=0.2~1.0, i-hydroxypropyl methylcellulose ene-viscosity ephezulu ene-total degree of substitution engaphezulu kwe-1.8 inyibilika kwizisombululo ze-anhydrous methanol kunye ne-ethanol, kwaye ine-thermos-plasticity kunye nokunyibilika kwamanzi. Ikwanyibilika kwi-hydrocarbons ezine-chlorine ezifana ne-methylene chloride kunye ne-chloroform, kunye nezinyibilikisi zendalo ezifana ne-acetone, isopropanol kunye ne-diacetone alcohol. Ukunyibilika kwayo kwi-organic solvents kungcono kunokunyibilika kwamanzi.
(2) Izinto Ezichaphazela Ukuqina Kwe-Hydroxypropyl Methyl Cellulose Ukumisela okuqhelekileyo kwe-hydroxypropyl methyl cellulose kufana nokwezinye ii-ether ze-cellulose. Kulinganiswa kwi-20°C ngesisombululo samanzi esiyi-2% njengomgangatho. Ukuqina kwemveliso efanayo kuyanda ngokunyuka koxinzelelo. Kwiimveliso ezinee-molecular weights ezahlukeneyo kuxinzelelo olufanayo, imveliso enobunzima obukhulu be-molecular inobunzima obuphezulu. Ubudlelwane bayo nobushushu bufana nobe-methyl cellulose. Xa ubushushu bunyuka, ukuqina buqala ukwehla, kodwa xa bufikelela kubushushu obuthile, ukuqina bunyuka ngequbuliso kwaye kwenzeka i-gelation. Ubushushu be-gel beemveliso ze-viscosity eziphantsi buphezulu. Inqaku layo le-gel alinxulumananga kuphela ne-viscosity ye-ether, kodwa linxulumene nomlinganiselo wokwakheka kweqela le-methoxyl kunye neqela le-hydroxypropyl kwi-ether kunye nobukhulu be-total substitution degree. Kufuneka kuqatshelwe ukuba i-hydroxypropyl methylcellulose nayo yi-pseudoplastic, kwaye isisombululo sayo sizinzile kubushushu begumbi ngaphandle kokonakala kwe-viscosity ngaphandle kokuba kunokwenzeka ukuba i-enzyme yonakale.
(3) Ukunyamezelana kwetyuwa ye-hydroxypropyl methylcellulose Ekubeni i-hydroxypropyl methylcellulose yi-ether engeyiyo i-ionic, ayifakwanga kwi-water media, ngokungafaniyo nezinye ii-ionic cellulose ethers, ezifana ne-carboxymethyl Base cellulose, kwisisombululo sokusabela kunye nee-heavy metal ion kunye ne-precipitate. Iityuwa eziqhelekileyo ezifana ne-chloride, i-bromide, i-phosphate, i-nitrate, njl. aziyi kuncipha xa zongezwa kwisisombululo sayo samanzi. Nangona kunjalo, ukongezwa kwetyuwa kunempembelelo ethile kubushushu be-flocculation yesisombululo sayo samanzi. Xa uxinzelelo lwetyuwa lusanda, ubushushu bejeli buyancipha. Xa uxinzelelo lwetyuwa lungaphantsi kwendawo ye-flocculation, i-viscosity yesisombululo idla ngokunyuka. Ke ngoko, inani elithile letyuwa longezwa, xa lisetyenziswa, linokufezekisa isiphumo sokutyeba ngakumbi ngokwezoqoqosho. Ke ngoko, kwezinye izicelo, kungcono ukusebenzisa umxube we-cellulose ether kunye netyuwa kunoxinzelelo oluphezulu lwesisombululo se-ether ukufezekisa isiphumo sokutyeba.
(4) I-Hydroxypropyl methylcellulose acid kunye nokumelana ne-alkali I-Hydroxypropyl methylcellulose iqhele ukuba izinzile kwii-asidi kunye ne-alkalis, kwaye ayichaphazeleki kuluhlu lwe-pH 2 ~ 12. Ingamelana nomlinganiselo othile we-asidi ekhanyayo, efana ne-formic acid, i-acetic acid, i-citric acid, i-succinic acid, i-phosphoric acid, i-boric acid, njl. Kodwa i-acid exutyiweyo inefuthe lokunciphisa i-viscosity. Ii-alkalis ezifana ne-caustic soda, i-caustic potash kunye namanzi ekalika azinampembelelo kuyo, kodwa zinokunyusa kancinci i-viscosity yesisombululo, zize zinciphise kancinci.
(5) Ukuxubana kwe-hydroxypropyl methylcellulose Isisombululo se-hydroxypropyl methylcellulose sinokuxutywa neekhompawundi ze-polymer ezinyibilikayo emanzini ukuze zibe sisisombululo esifanayo nesicacileyo esine-viscosity ephezulu. Ezi khompawundi ze-polymer ziquka i-polyethylene glycol, i-polyvinyl acetate, i-polysilicone, i-polymethylvinyl siloxane, i-hydroxyethyl cellulose, kunye ne-methyl cellulose. Iikhompawundi ze-molecular eziphezulu zendalo ezifana ne-gum arabic, i-locust bean gum, i-karaya gum, njl. nazo zihambelana kakuhle nesisombululo sayo. I-Hydroxypropyl methylcellulose ingaxutywa ne-mannitol ester okanye i-sorbitol ester ye-stearic acid okanye i-palmitic acid, kwaye ingaxutywa ne-glycerin, i-sorbitol kunye ne-mannitol, kwaye ezi khompawundi zingasetyenziswa njenge-hydroxypropyl methylcellulose Plasticizer ye-cellulose.
(6) I-enyibilikayo emanzini enganyibilikiyoii-ether ze-cellulosei-hydroxypropyl methylcellulose inokwenza i-surface cross-linking kunye ne-aldehydes, ukuze ezi ethers zinyibilikayo emanzini zingene kwisisombululo kwaye zinganyibiliki emanzini. Ii-aldehydes ezenza i-hydroxypropyl methylcellulose inganyibiliki ziquka i-formaldehyde, i-glyoxal, i-succinic aldehyde, i-adipaldehyde, njl. Xa usebenzisa i-formaldehyde, kufuneka kunikwe ingqalelo ekhethekileyo kwixabiso le-pH yesisombululo, apho i-glyoxal isabela ngokukhawuleza, ngoko ke i-glyoxal isetyenziswa kakhulu njenge-agent ye-crosslinking kwimveliso yemizi-mveliso. Umthamo wolu hlobo lwe-agent ye-crosslinking kwisisombululo yi-0.2% ~ 10% yobunzima be-ether, kungcono i-7% ~ 10%, umzekelo, i-3.3% ~ 6% ye-glyoxal yeyona ifanelekileyo. Ngokubanzi, ubushushu bonyango yi-0 ~ 30℃, kwaye ixesha liyi-1 ~ 120min. I-crosslinking reaction kufuneka yenziwe phantsi kweemeko ze-asidi. Ngokubanzi, i-pH yesisombululo ilungiswa ibe malunga ne-2~6 ngokongeza i-asidi enamandla engaphiliyo okanye i-asidi ye-carboxylic ye-organic kwisisombululo, kungcono ukuba ibe phakathi kwe-4~6, emva koko kongezwa ii-aldehydes ukuze kwenziwe i-reaction ye-crosslinking. I-asidi esetyenzisiweyo ine-hydrochloric acid, i-sulfuric acid, i-phosphoric acid, i-formic acid, i-acetic acid, i-hydroxy-acetic acid, i-succinic acid okanye i-citric acid njl., apho i-formic acid okanye i-acetic acid kuyacetyiswa, kwaye i-formic acid ifanelekile. I-asidi kunye ne-aldehyde zingongezwa ngaxeshanye ukuvumela isisombululo ukuba singene kwi-cross-linking reaction ngaphakathi koluhlu lwe-pH olufunekayo. Olu tshintsho ludla ngokusetyenziswa kwinkqubo yokugqibela yonyango kwinkqubo yokulungiselela ii-cellulose ethers. Emva kokuba i-cellulose ether inganyibiliki, kulula ukuyisebenzisa.
Amanzi angama-20~25℃ okuhlamba nokucoca. Xa imveliso isetyenziswa, izinto ze-alkaline zingongezwa kwisisombululo semveliso ukuze kulungiswe i-pH yesisombululo ukuba ibe yi-alkaline, kwaye imveliso iya kunyibilika kwisisombululo ngokukhawuleza. Le ndlela ikwasebenza nakwindlela yokulungisa ifilimu emva kokuba isisombululo se-cellulose ether senziwe ifilimu ukuze sibe yifilimu enganyibilikiyo.
(7) Ukumelana ne-enzyme ye-hydroxypropyl methylcellulose ngokwethiyori yi-cellulose derivatives, njengeqela ngalinye le-anhydroglucose, ukuba kukho iqela elibambene ngokuqinileyo, akulula ukosulelwa ziintsholongwane, kodwa eneneni imveliso egqityiweyo Xa ixabiso lokutshintshwa lidlula i-1, liya konakaliswa zii-enzyme, oko kuthetha ukuba inqanaba lokutshintshwa kweqela ngalinye kwi-cellulose chain alifani ngokwaneleyo, kwaye iintsholongwane zinokubola kwiqela le-anhydroglucose elingafakwanga endaweni enye ukuze lenze iiswekile, njengezondlo ukuze iintsholongwane zifunxe. Ke ngoko, ukuba inqanaba lokutshintshwa kwe-cellulose ether liyanda, ukumelana nokubola kwe-enzymatic ye-cellulose ether nako kuya kwanda. Ngokweengxelo, phantsi kweemeko ezilawulwayo, iziphumo ze-hydrolysis zee-enzymes ezenziweyo, i-viscosity eseleyo ye-hydroxypropyl methylcellulose (DS=1.9) yi-13.2%, i-methylcellulose (DS=1.83) yi-7.3%, i-methylcellulose (DS=1.66) yi-3.8%, kwaye i-hydroxyethyl cellulose yi-1.7%. Kuyabonakala ukuba i-hydroxypropyl methylcellulose inamandla okulwa nee-enzyme. Ke ngoko, ukumelana okuhle kwee-enzyme ze-hydroxypropyl methylcellulose, kunye neempawu zayo ezilungileyo zokusasazeka, ukuqina kunye nokwenza ifilimu, isetyenziswa kwiingubo ze-emulsion zamanzi, njl.njl., kwaye ngokubanzi akufuneki kongezwe izigcini. Nangona kunjalo, ukuze kugcinwe isisombululo ixesha elide okanye ungcoliseko olunokwenzeka oluvela ngaphandle, izigcini zingongezwa njengesilumkiso, kwaye ukhetho lunokugqitywa ngokweemfuno zokugqibela zesisombululo. I-Phenylmercuric acetate kunye ne-manganese fluorosilicate zizivigcini ezisebenzayo, kodwa zonke zinobuthi, kufuneka kuqwalaselwe ukusebenza. Ngokubanzi, i-1~5mg ye-phenylmercury acetate ingongezwa kwisisombululo ngelitha nganye yedosi.
(8) Ukusebenza kwei-hydroxypropyl methylcelluloseIfilimu iHydroxypropyl methylcellulose ineempawu ezintle kakhulu zokwenza ifilimu. Isisombululo sayo samanzi okanye isisombululo se-organic solvent sigqunywe kwipleyiti yeglasi, kwaye asibi nambala kwaye sibonakale emva kokomiswa. Kwaye siqinile. Sinokumelana nokufuma okuhle kwaye sihlala siqinile kumaqondo obushushu aphezulu. Ukuba i-hygroscopic plasticizer yongezwa, ukwandiswa kwayo kunye nokuguquguquka kwayo kunokuphuculwa. Ngokuphathelele ukuphucula ukuguquguquka, ii-plasticizers ezifana ne-glycerin kunye ne-sorbitol zezona zifanelekileyo. Ngokubanzi, uxinaniso lwesisombululo yi-2% ~ 3%, kwaye ubungakanani be-plasticizer yi-10% ~ 20% ye-cellulose ether. Ukuba umxholo we-plasticizer uphezulu kakhulu, i-colloidal dehydration shrinkage iya kwenzeka xa kufuma okuphezulu. Amandla okuxinana kwefilimu ene-plasticizer eyongeziweyo makhulu kakhulu kunaleyo ingenayo i-plasticizer, kwaye iyanda xa kunyuswa ubungakanani obongeziweyo. Ngokuphathelele i-hygroscopicity yefilimu, iyanda xa kunyuswa ubungakanani be-plasticizer.
Ixesha leposi: Epreli-25-2024