Hunhu hwehydroxypropyl methylcellulose

Hydroxypropyl methylcellulose HPMC imhando ye non-ionic cellulose mixed ether. Kusiyana ne ionic methyl carboxymethyl cellulose mixed ether, haibatikane nesimbi dzinorema. Nekuda kwehuwandu hwakasiyana hwe methoxyl nehuwandu hwe hydroxypropyl mu hydroxypropyl methylcellulose uye viscosities dzakasiyana, kune mhando dzakawanda dzine hunhu hwakasiyana, semuenzaniso, huwandu hwakawanda hwe methoxyl uye huwandu hwakaderera hwe hydroxypropyl. Kushanda kwayo kwakafanana nekwe methyl cellulose, nepo huwandu hwakaderera hwe methoxyl uye huwandu hwakawanda hwe hydroxypropyl hwakaenzana nehwe hydroxypropyl methyl cellulose. Zvisinei, mumhando yega yega, kunyangwe huwandu hushoma hwe hydroxypropyl kana huwandu hushoma hwe methoxyl group huripo, kune misiyano mikuru mukunyungudika mu organic solvents kana tembiricha ye flocculation mu aqueous solutions.

(1) Hunhu hwekunyungudika kwehydroxypropyl methylcellulose

①Kunyungudika kwehydroxypropyl methylcellulose mumvura Hydroxypropyl methylcellulose chaizvoizvo rudzi rwemethylcellulose yakagadziridzwa nepropylene oxide (methoxypropylene), saka ichiri nechimiro chakafanana nemethyl cellulose Cellulose ine hunhu hwakafanana hwekunyungudika kwemvura inotonhora uye kusanyungudika kwemvura inopisa. Zvisinei, nekuda kweboka rehydroxypropyl rakagadziriswa, tembiricha yayo ye gelation mumvura inopisa yakakwira zvikuru kupfuura yemethyl cellulose. Semuenzaniso, viscosity yehydroxypropyl methylcellulose aqueous solution ine 2% methoxy content substitution degree DS=0.73 uye hydroxypropyl content MS=0.46 i500 mpa·s pa20°C, uye tembiricha yayo yegel Inogona kusvika pedyo ne100°C, nepo methyl cellulose patembiricha imwechete iri 55°C chete. Kana iri yekunyungudika kwayo mumvura, yakagadziridzwawo zvikuru. Semuenzaniso, hydroxypropyl methylcellulose yakapwanywa (yakaumbwa negranular shape 0.2 ~ 0.5mm pa20°C ine viscosity ye4% yemvura ye2pa•s inogona kutengwa paIri tembiricha yemukamuri, inonyungudika nyore nyore mumvura isina kutonhora.

②Kunyungudika kwehydroxypropyl methylcellulose muzvinhu zvinonyungudika zveorganic Kunyungudika kwehydroxypropyl methylcellulose muzvinhu zvinonyungudika zveorganic kuri naniwo pane kwemethylcellulose. Pazvigadzirwa zviri pamusoro pe2.1, high-viscosity hydroxypropyl methylcellulose ine hydroxypropyl MS=1.5~1.8 uye methoxy DS=0.2~1.0, ine huwandu hwese hwekutsiva pamusoro pe1.8, inonyungudika muanhydrous methanol ne ethanol solutions. Yepakati, uye thermoplastic uye inonyungudika mumvura. Inonyungudikawo mu chlorinated hydrocarbons dzakadai semethylene chloride ne chloroform, uye organic solvents dzakadai seacetone, isopropanol uye diacetone alcohol. Kunyungudika kwayo muzvinhu zvinonyungudika zveorganic kuri nani pane mvura inonyungudika.

(2) Zvinhu zvinokanganisa viscosity yehydroxypropyl methylcellulose Kuongororwa kwe viscosity yehydroxypropyl methylcellulose kwakafanana nemamwe ma cellulose ethers, uye kunoyerwa pa20°C ne 2% aqueous solution seyakajairwa. Viscosity yechigadzirwa chimwe chete inowedzera nekuwedzera kwe concentration. Kune zvigadzirwa zvine mamorekuru akasiyana ane concentration imwe chete, chigadzirwa chine mamorekuru akawanda chine viscosity yakakwira. Hukama hwayo netembiricha hwakafanana nehwe methyl cellulose. Kana tembiricha yakwira, viscosity inotanga kudzikira, asi kana yasvika patembiricha yakati,

Viscosity inomuka kamwe kamwe uye gelation inoitika. Tembiricha yegel yezvigadzirwa zvine viscosity yakaderera yakakwira. Nzvimbo yayo yegel haina kungova ne viscosity ye ether chete, asiwo ine chekuita nehuwandu hwekuumbwa kwe methoxyl group ne hydroxypropyl group mu ether uye saizi ye total substitution degree. Zvinofanira kucherechedzwa kuti hydroxypropyl methylcellulose ipseudoplastic zvakare, uye mhinduro yayo yakagadzikana patembiricha yemumba isina kuora kwe viscosity kunze kwekunge paine mukana we enzyme degradation.

(3) Kushivirira munyu kwehydroxypropyl methylcellulose Sezvo hydroxypropyl methylcellulose isiri ionic ether, haisanganisike mumvura, kusiyana nemamwe ma ionic cellulose ethers. Semuenzaniso, carboxymethyl cellulose inosangana nema heavy metal ions uye inobuda mumushonga. Munyu wakajairika wakadai sechloride, bromide, phosphate, nitrate, nezvimwewo hauzopindi mvura kana wawedzerwa mumushonga wayo wemvura. Zvisinei, kuwedzerwa kwemunyu kune simba pakupisa kwe flocculation kwemushonga wayo wemvura. Kana munyu wakawanda, tembiricha yegel inoderera. Kana munyu wakawanda uri pasi pe flocculation point, viscosity yemushonga inowanzo kuwedzera. Nokudaro, huwandu hwakati hwemunyu hunowedzerwa. , mukushandiswa, inogona kuwana thickening effect zvishoma nezvishoma. Nokudaro, mune zvimwe zvinoshandiswa, zviri nani kushandisa musanganiswa we cellulose ether nemunyu pane huwandu hwakawanda hwe ether solution kuti uwane thickening effect.

(4) Hydroxypropyl methylcellulose acid uye alkali resistance Hydroxypropyl methylcellulose inowanzo gadzikana kune acids uye alkalis, uye haikanganisike muhuwandu hwe pH 2 ~ 12. Inogona kutsungirira huwandu hwakati hweLight acids, senge formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, nezvimwewo. Asi concentrated acid ine simba rekuderedza viscosity. Alkalis dzakadai se caustic soda, caustic potash uye lime water hadzina simba pairi, asi dzinogona kuwedzera viscosity yemushonga zvishoma, uye dzozoideredza zvishoma nezvishoma.

(5) Kusanganiswa kwehydroxypropyl methylcellulose Hydroxypropyl methylcellulose solution inogona kusanganiswa nepolymer compounds dzinonyungudika mumvura kuti ive mhinduro yakafanana uye yakajeka ine viscosity yakakwira. Ma polymer compounds aya anosanganisira polyethylene glycol, polyvinyl acetate, polysilicone, polymethylvinylsiloxane, hydroxyethyl cellulose, uye methyl cellulose. Ma molecules echisikigo akadai segum arabic, locust bean gum, karaya gum, nezvimwewo ane hukama hwakanaka ne solution yayo. Hydroxypropyl methylcellulose inogonawo kusanganiswa ne mannitol ester kana sorbitol ester ye stearic acid kana palmitic acid, uye inogonawo kusanganiswa ne glycerin, sorbitol ne mannitol, uye ma compositions aya anogona kushandiswa se hydroxypropyl methylcellulose Plasticizer ye cellulose.

(6) Maether e-cellulose asinganyunguduke mumvura ehydroxypropyl methylcellulose anogona kusanganiswa ne aldehydes pamusoro, kuitira kuti aya maether anonyunguduka mumvura anyunguduke mumvura uye asanyunguduke. Ma aldehydes anoita kuti hydroxypropyl methylcellulose isanyunguduke anosanganisira formaldehyde, glyoxal, succinic aldehyde, adipaldehyde, nezvimwewo. Pakushandisa formaldehyde, kutarisisa kwakakosha kunofanirwa kupihwa kune pH yemushonga, iyo glyoxal inokurumidza kuita, saka glyoxal inowanzo shandiswa se crosslinking agent mukugadzirwa kwemaindasitiri. Huwandu hwemhando iyi ye crosslinking agent mumushonga i0.2%~10% yehuremu hwe ether, zviri nani 7%~10%, semuenzaniso, 3.3%~6% ye glyoxal ndiyo yakakodzera. Kazhinji, kurapwa

Tembiricha iri 0~30℃, uye nguva yacho i1~120min. Kupindirana kwekubatanidza kunofanirwa kuitwa mumamiriro ezvinhu ane acidic. Kazhinji, mhinduro inotanga yawedzerwa ne inorganic strong acid kana organic carboxylic acid kugadzirisa pH yemhinduro kusvika pa2~6, zviri nani pakati pe4~6, wobva wawedzera aldehydes kuti uite cross-linking reaction. Asidhi inoshandiswa ine hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid kana citric acid nezvimwewo, umo formic acid kana acetic acid zvinokurudzirwa, uye formic acid ndiyo yakanakisisa. Asidhi nealdehyde zvinogonawo kuwedzerwa panguva imwe chete kuti mhinduro iite cross-linking reaction mukati me pH range inodiwa. Kupindirana uku kunowanzo shandiswa mukugadzirisa kwekupedzisira mukugadzirira cellulose ethers. Mushure mekunge cellulose ether isisanyungudike, zviri nyore kushandisa.

Mvura ye20~25℃ yekugeza nekuchenesa. Kana chigadzirwa ichi chichishanda, zvinhu zvine alkaline zvinogona kuwedzerwa mumushonga wechigadzirwa kuti zvigadzirise pH yemushonga kuti ive alkaline, uye chigadzirwa chichanyunguduka mumushonga nekukurumidza. Nzira iyi inoshandawo pakugadzirisa firimu mushure mekunge mhinduro ye cellulose ether yagadzirwa kuita firimu kuti ive firimu risinganyungudike.

(7) Kuramba kwe enzyme ye hydroxypropyl methylcellulose inyaya ye cellulose derivatives, senge boka rega rega re anhydroglucose, kana paine boka rakatsiga rakabatana, hazvisi nyore kutapukirwa ne microorganisms, asi kutaura chokwadi chigadzirwa chakapedzwa Kana kukosha kwekutsiva kuchidarika 1, kuchaderedzwawo nema enzymes, zvinoreva kuti mwero wekutsiva weboka rega rega pane cellulose chain hauna kufanana zvakakwana, uye microorganisms dzinogona kuparara paboka re anhydroglucose risina kutsiviwa kuti rigadzire shuga, sekudya kunovaka muviri kuti microorganisms dzitore. Saka, kana mwero wekutsiva cellulose ne etherification ukawedzera, kuramba kwe enzymatic erosion ye cellulose ether kuchawedzerawo. Zvinoenderana nemishumo, pasi pemamiriro ezvinhu akadzorwa, hydrolysis inobuda muma enzymes, viscosity yakasara ye hydroxypropyl methylcellulose (DS=1.9) iri 13.2%, methylcellulose (DS=1.83) iri 7.3%, methylcellulose (DS=1.66) iri 3.8%, uye hydroxyethyl cellulose iri 1.7%. Zvinogona kuonekwa kuti hydroxypropyl methylcellulose ine simba rakasimba rekurwisa ma enzyme. Nokudaro, kuramba kwakanaka kwema enzyme kwe hydroxypropyl methylcellulose, pamwe chete nekupararira kwayo kwakanaka, kukora uye kugadzira firimu, inoshandiswa mu water-emulsion coatings, nezvimwewo, uye kazhinji haidi kuwedzera ma preservatives. Zvisinei, kuti mhinduro ichengetwe kwenguva refu kana kusvibiswa kunogona kubva kunze, ma preservatives anogona kuwedzerwa senzira yekudzivirira, uye sarudzo inogona kusarudzwa zvichienderana nezvinodiwa zvekupedzisira zvemhinduro. Phenylmercuric acetate uye manganese fluorosilicate ma preservatives anoshanda, asi ese ane Toxicity, kutarisirwa kunofanira kupihwa pakushanda. Kazhinji, 1~5mg yephenylmercury acetate inogona kuwedzerwa mumushonga pa litre imwe neimwe yemuyero.

(8) Kushanda kwefirimu rehydroxypropyl methylcellulose Hydroxypropyl methylcellulose ine hunhu hwakanaka hwekuumba firimu. Mhinduro yayo yemvura kana organic solvent inoputirwa pagirazi, uye inova isina ruvara uye yakajeka mushure mekuoma. Uye firimu yakasimba. Ine hunyoro hwakanaka uye inoramba yakasimba pakupisa kwakanyanya. Kana hygroscopic plasticizer ikawedzerwa, kureba kwayo uye kuchinjika kwayo kunogona kuwedzerwa. Panyaya yekuvandudza kuchinjika, mapurasitiki akadai seglycerin nesorbitol ndiwo anonyanya kukodzera. Kazhinji, huwandu hwemhinduro i2% ~ 3%, uye huwandu hweplasticizer i10% ~ 20% ye cellulose ether. Kana zviri mukati me plasticizer zvakawandisa, colloidal dehydration shrinkage ichaitika pahunyoro hwakawanda. Simba rekumanikidza refirimu rine

Chinoiswa mupurasitiki chakakura kupfuura chisina chinobva mupurasitiki, uye chinowedzera kana huwandu hwacho hukawedzera. Kana iri hygroscopicity yefirimu, chinowedzerawo kana huwandu hwepurasitiki hukawedzera.


Nguva yekutumira: Mbudzi-24-2022