Saamaynta dhumucda ee hydroxypropyl methylcellulose

Hydroxypropyl methylcellulose wuxuu ku siinayaa hoobiye qoyan oo leh viscosity aad u fiican, kaas oo si weyn u kordhin kara awoodda isku xirnaanta ee u dhaxaysa hoobiye qoyan iyo lakabka saldhigga, iyo hagaajinta waxqabadka anti-sag ee hoobiye.Waxaa si weyn loo isticmaalaa in lagu dhejiyo hoobiye, nidaamka dahaarka derbiga dibadda iyo xidhitaanka leben hoobiye.Saamaynta dhumucdeeda ee ether cellulose sidoo kale waxay kordhin kartaa isku midka ah iyo awoodda ka-hortagga kala-firdhinta walxaha cusub ee sibidhka ku salaysan, ka hortagga delamination, kala-soocidda iyo dhiig-baxa hoobiye iyo shubka, waxaana loo isticmaali karaa shubka fiber-ka, shubka biyaha hoostiisa iyo shubka is-xakamaynta. .

Hydroxypropyl methylcelluloseHPMCwaxay kordhisaa viscosity ee walxaha sibidhka ku salaysan ee ka soo baxa xuubka etherka cellulose.Tusmada "viscosity" waxaa badanaa loo isticmaalaa si loo qiimeeyo viscosity of cellulose ether xal.Viscosity of ether cellulose guud ahaan waxa loola jeedaa xal ether cellulose oo leh xad gaar ah (sida 2%).Xawaaraha (ama heerka wareega, sida 20 rpm), qiimaha viscosity ee lagu cabiray qalab cabbireed cayiman (sida viscometer wareeg ah).

Viscosity waa halbeeg muhiim ah oo lagu qiimeeyo waxqabadka etherka cellulose.Marka uu sareeyo viscosity ee xalka hydroxypropyl methylcellulose, ayaa si fiican u nuugaya walxaha sibidhka ku salaysan, way ka sii fiicnaanaysaa adhesionka substrate-ka, iyo sida ugu wanaagsan ee ka hortagga sagging iyo ka hortagga kala firdhinta.Xoog badan, laakiin haddii uu viscositykiisu aad u weyn yahay, waxay saamayn doontaa dareeraha iyo shaqaynta alaabta sibidhka ku salaysan (sida ku dhejinta mindida dhejiska marka lagu dhejiyo dhismaha hoobiye).Sidaa darteed, viscosity ether cellulose ee loo isticmaalo hoobiye-qalalan-qallalan inta badan waa 15,000 ~ 60,000 mPa.S-1, hoobiyeyaasha is-miidaaminta iyo shubka is-xakamaynta, kuwaas oo u baahan dheecaan sare, waxay u baahan yihiin viscosity hoose ee eter cellulose.

Intaa waxaa dheer, saameynta dhumucda ee hydroxypropyl methylcellulose waxay kordhin doontaa baahida biyaha ee walxaha ku salaysan sibidhka, taas oo kordhinaysa dhalidda hoobiye.

Viscosity ee xalalka hydroxypropyl methylcellulose waxay kuxirantahay arrimahan soo socda:

Miisaanka molecular (ama heerka polymerization) iyo fiirsashada ether cellulose, heerkulka xalka, heerka dhogorta iyo habka tijaabada.

1. Heerka sare ee polymerization of cellulose ether iyo miisaanka molecular weyn, sare viscosity ee xal aqueous;

2. The sare qiyaasta (ama fiirsashada) ee ether cellulose, sare viscosity ee ay xal aqueous, laakiin taxadar waa in la qaadaa si loo doorto qiyaasta ku haboon marka la isticmaalayo, si aanay u saamayn waxqabadka hoobiye iyo shubka haddii qiyaasta ayaa aad u sareysa;

3. Sida dareerayaasha intooda badan, viscosity of cellulose ether xal waxay hoos u dhigi doontaa korodhka heerkulka, iyo xoojinta sare ee ether-ka cellulose, saamaynta heerkulka;

4. Xalka cellulose ether inta badan waa pseudoplastic, kaas oo leh hantida khafiifinta xiirta.Markasta oo uu bato heerka dhogorta inta lagu jiro baaritaanka, ayaa hoos u dhigaya viscosity-ga.

Sidaa darteed, isku-xidhka hoobiyeyaasha ayaa hoos u dhici doona sababtoo ah xooga dibadda ah, taas oo faa'iido u leh dhismaha xoqidda hoobiye, si ay hoobiyeyaashu u yeeshaan karti shaqo iyo isku-xirnaan wanaagsan isla mar ahaantaana.Si kastaba ha noqotee, xalka ether-ka cellulose wuxuu soo bandhigi doonaa sifooyinka dheecaanka Newtonian marka xoogasaarku aad u yar yahay oo mawgu yar yahay.Marka fiirsigu kordho, xalku si tartiib tartiib ah ayuu u soo bandhigi doonaa sifooyinka dareeraha pseudoplastic, iyo inta badan feejignaanta, waxay sii caddahay pseudoplasticity.