Hydroxypropyl methylcelluloseimhando 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 kushanda kwehuwandu hwakaderera hwe methoxyl uye huwandu hwakawanda hwe hydroxypropyl kwakafanana nekwe hydroxypropyl methyl cellulose. Zvisinei, mumhando yega yega, kunyangwe huwandu hushoma hwe hydroxypropyl group 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
① Kunyungudika kwehydroxypropyl methylcellulose mumvuraHydroxypropyl methylcelluloseChaizvoizvo imhando yemethylcellulose yakagadziriswa nepropylene oxide (methoxy-propylene), saka ichiri nehunyanzvi hwakafanana nemethyl cellulose ine hunhu hwakafanana hwekunyungudika kwemvura inotonhora uye kusanyungudika kwemvura inopisa. Zvisinei, nekuda kweboka rehydroxypropyl rakagadziriswa, tembiricha yayo ye gelation mumvura inopisa yakakwira zvakanyanya 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 padyo 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 patembiricha yemumba, inonyungudika nyore nyore mumvura isina kutonhora.
② Kunyungudika kwehydroxypropyl methylcellulose mu organic solvents, kunyungudika kwehydroxypropyl methylcellulose mu organic solvents kuri naniwo kupfuura kwemethylcellulose. Methylcellulose inofanira kuva ne methoxyl substitution degree ye2.1. Zvigadzirwa zvataurwa pamusoro apa, asi zvine hydroxypropyl MS=1.5~1.8 uye methoxy DS=0.2~1.0, high-viscosity hydroxypropyl methylcellulose ine total degree of substitution iri pamusoro pe1.8 inonyungudika mu anhydrous methanol uye ethanol solutions, uye ine thermos-plasticity uye water solubility. Inonyungudikawo mu chlorinated hydrocarbons dzakadai se methylene chloride ne chloroform, uye organic solvents dzakadai se acetone, isopropanol uye diacetone alcohol. Kunyungudika kwayo mu organic solvents kuri nani pane water solubility.
(2) Zvinhu Zvinokanganisa Kusviba kweHydroxypropyl Methyl Cellulose Kuongororwa kweviscosity yehydroxypropyl methyl cellulose kwakafanana nekwemamwe ma cellulose ethers. Inoyerwa pa20°C ne 2% aqueous solution seyakajairwa. Viscosity yechigadzirwa chimwe chete inowedzera nekuwedzera kwekusviba. Kune zvigadzirwa zvine mamorekuru akasiyana pahuwandu hwakafanana, chigadzirwa chine mamorekuru akawanda chine viscosity yakakwira. Hukama hwayo netembiricha hwakafanana nehwemethyl cellulose. Kana tembiricha yakwira, viscosity inotanga kudonha, asi kana yasvika patembiricha yakati, viscosity inomuka kamwe kamwe uye gelation inoitika. Tembiricha yegel yezvigadzirwa zvine viscosity yakaderera yakakwira. Poindi yayo yegel haina kungoenderana nekusviba kweether chete, asiwo ine chekuita ne composition ratio ye methoxyl group ne hydroxypropyl group mu ether nehukuru hwe total substitution degree. Zvinofanira kucherechedzwa kuti hydroxypropyl methylcellulose ipurasitikiwo, uye mhinduro yayo inogara yakagadzikana patembiricha yemumba pasina kuora kwe viscosity kunze kwekunge paine mukana wekuora kwe enzyme.
(3) Kushivirira munyu kwehydroxypropyl methylcellulose Sezvo hydroxypropyl methylcellulose isiri ionic ether, haina ionized mumvura, kusiyana nemamwe ma ionic cellulose ethers, akadai se carboxymethyl Base cellulose, mumushonga wekuita nema heavy metal ions uye precipitate. Munyu wakajairika wakadai se chloride, bromide, phosphate, nitrate, nezvimwewo hauzonyuki 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 inowanzowedzera. Naizvozvo, huwandu hwakati hwemunyu hunowedzerwa, mukushandiswa, hunogona kuita kuti munyu uwedzere hupfumi. Nokudaro, mune zvimwe zvinoshandiswa, zviri nani kushandisa musanganiswa we cellulose ether nemunyu pane huwandu hwakawanda hwemushonga we ether kuti uwane mugumisiro wekunyukidza.
(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 hweasidhi yakareruka, 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, polymethylvinyl siloxane, 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) Chinhu chisinganyungudike mumvuraethers dze celluloseyehydroxypropyl methylcellulose inogona kuita cross-linking pamusoro nealdehydes, kuitira kuti aya ma ether anonyungudika mumvura anyungudike mumushonga uye asanyungudike mumvura. Ma aldehydes anoita kuti hydroxypropyl methylcellulose isanyungudike anosanganisira formaldehyde, glyoxal, succinic aldehyde, adipaldehyde, nezvimwewo. Pakushandisa formaldehyde, kutarisisa kwakanyanya kunofanirwa kupihwa kune pH yemushonga, iyo glyoxal inokurumidza kuita, saka glyoxal inowanzo shandiswa se crosslinking agent mukugadzirwa kwemaindasitiri. Chiyero chemhando iyi ye crosslinking agent mumushonga i0.2%~10% yehuremu hwe ether, zviri nani 7%~10%, semuenzaniso, 3.3%~6% ye glyoxal ndiyo yakakodzera. Kazhinji, tembiricha yekurapa i0~30℃, uye nguva i1~120min. Crosslinking reaction inofanira kuitwa mumamiriro ezvinhu ane acidic. Kazhinji, pH yemushonga inogadziriswa kuita 2~6 nekuwedzera inorganic strong acid kana organic carboxylic acid mumushonga, zviri nani pakati pe4~6, uye maaldehydes anowedzerwa kuti aite crosslinking reaction. Asidhi inoshandiswa ine hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxy-acetic acid, succinic acid kana citric acid nezvimwewo, umo formic acid kana acetic acid zvinokurudzirwa, uye formic acid ndiyo yakanakisisa. Acid nealdehyde zvinogonawo kuwedzerwa panguva imwe chete kuti mhinduro iite cross-linking reaction mukati me pH range inodiwa. Iyi reaction inowanzo shandiswa mukurapa kwekupedzisira mukugadzirira cellulose ethers. Kana cellulose ether isisina kunyungudika, 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, sezvinovaka muviri kuti microorganisms dzitore. Saka, kana mwero wekutsiva cellulose ne etherification ukawedzera, kuramba kwe enzyme erosion ye cellulose ether kuchawedzerawo. Zvinoenderana nemishumo, pasi pemamiriro ezvinhu akadzorwa, mhedzisiro yehydrolysis yemaenzymes akagadzirwa, iyo residual viscosity yehydroxypropyl 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 maenzyme. Nokudaro, hydroxypropyl methylcellulose inodzivisa maenzyme zvakanaka, 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, kutarisisa kunofanira kupihwa pakushanda. Kazhinji, 1~5mg yephenylmercury acetate inogona kuwedzerwa mumushonga pa litre imwe neimwe yemuyero.
(8) Kuitwa kwehydroxypropyl methylcelluloseFirimu 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 huwandu hweplasticizer hwakanyanya, colloidal dehydration shrinkage hunoitika kana hunyoro hwakawanda. Simba rekudhonza refirimu rine plasticizer rakawedzerwa rakakura kupfuura risina plasticizer, uye rinowedzera nekuwedzera kwehuwandu hwakawedzerwa. Kana iri hygroscopicity yefirimu, inowedzerawo nekuwedzera kwehuwandu hweplasticizer.
Nguva yekutumira: Kubvumbi-25-2024