Methylcellulose (MC)
Tsarin kwayoyin halitta na methylcellulose (MC) shine:
[C6H7O2(OH)3-h(OCH3)n\]x
Tsarin samarwa shine a yi cellulose ether ta hanyar jerin halayen bayan an yi wa audugar da aka tace magani da alkali, kuma ana amfani da methyl chloride a matsayin wakilin etherification. Gabaɗaya, matakin maye gurbin shine 1.6~2.0, kuma narkewar shi ma ya bambanta da matakan maye gurbin daban-daban. Yana cikin cellulose ether wanda ba ionic ba.
Methylcellulose yana narkewa a cikin ruwan sanyi, kuma zai yi wuya a narke a cikin ruwan zafi. Maganin ruwansa yana da ƙarfi sosai a cikin kewayon pH = 3 ~ 12.
Yana da kyau a yi amfani da sitaci, guar gum, da sauransu, da kuma wasu nau'ikan surfactants. Idan zafin ya kai zafin gelation, gelation yana faruwa.
Rikewar methylcellulose a cikin ruwa ya dogara da adadin da aka ƙara masa, danko, kyawun barbashi da kuma yawan narkewar sa.
Gabaɗaya, idan adadin ƙarin ya yi yawa, ƙarancin ya yi ƙanƙanta, kuma ɗanɗanon ya yi yawa, ƙimar riƙe ruwa yana da yawa. Daga cikinsu, adadin ƙarin yana da babban tasiri akan ƙimar riƙe ruwa, kuma matakin ɗanɗanon ba ya daidai da matakin riƙe ruwa kai tsaye. Yawan narkewar ya dogara ne akan matakin gyaran saman ƙwayoyin cellulose da ƙarancin barbashi.
Daga cikin ƙwayoyin cellulose da ke sama, methyl cellulose da hydroxypropyl methyl cellulose suna da yawan riƙe ruwa.
Carboxymethylcellulose (CMC)
Carboxymethyl cellulose, wanda kuma aka sani da sodium carboxymethyl cellulose, wanda aka fi sani da cellulose, cmc, da sauransu, wani nau'in polymer ne mai layi na anionic, gishirin sodium na cellulose carboxylate, kuma yana da sabuntawa kuma ba ya ƙarewa. Kayan sinadarai.
Ana amfani da shi galibi a masana'antar sabulun wanki, masana'antar abinci da kuma ruwan haƙa mai a filin mai, kuma adadin da ake amfani da shi a fannin kayan kwalliya ya kai kusan kashi 1%.
Ana yin sinadarin ionic cellulose ether daga zare na halitta (auduga, da sauransu) bayan an yi maganin alkali, ana amfani da sodium monochloroacetate a matsayin maganin etherification, sannan ana yin jerin magungunan amsawa.
Matsakaicin matakin maye gurbin gabaɗaya shine 0.4 ~ 1.4, kuma aikin sa yana da matuƙar tasiri ta hanyar matakin maye gurbin.
CMC tana da kyakkyawan ikon ɗaurewa, kuma ruwan da ke cikinta yana da kyakkyawan ikon dakatarwa, amma babu ainihin ƙimar lalata filastik.
Lokacin da CMC ya narke, depolymerization yana faruwa a zahiri. Danko yana fara tashi yayin narkewa, yana ratsawa ta matsakaicin, sannan ya faɗi zuwa wani wuri mai faɗi. Danko da ya haifar yana da alaƙa da depolymerization.
Matsayin depolymerization yana da alaƙa da adadin ƙarancin mai narkewa (ruwa) a cikin tsarin. A cikin tsarin mai narkewa mara kyau, kamar man goge baki wanda ke ɗauke da glycerin da ruwa, CMC ba zai cire polymeris gaba ɗaya ba kuma zai kai ga ma'aunin daidaito.
Idan aka samu isasshen ruwa, CMC da aka maye gurbinsa da ruwa mai kyau zai fi sauƙin cire polymerize fiye da CMC da aka maye gurbinsa da ruwa mai yawa.
Hydroxyethylcellulose (HEC)
Ana yin HEC ta hanyar shafa auduga mai kyau da alkali, sannan a yi amfani da ethylene oxide a matsayin wakilin etherification a gaban acetone. Matsakaicin maye gurbinsa gabaɗaya shine 1.5 ~ 2.0. Yana da ƙarfi mai ƙarfi kuma yana da sauƙin sha danshi.
Hydroxyethyl cellulose yana narkewa a cikin ruwan sanyi, amma yana da wuya a narke a cikin ruwan zafi. Maganin sa yana da ƙarfi a zafin jiki mai yawa ba tare da yin gel ba.
Yana da daidaito ga acid da tushe na yau da kullun. Alkalis na iya hanzarta narkewarsa kuma ya ƙara ɗanɗanonsa. Watsewarsa a cikin ruwa ya ɗan fi muni fiye da na methyl cellulose da hydroxypropyl methyl cellulose.
Cellulose na Hydroxypropyl Methyl (HPMC)
Tsarin kwayoyin halitta na HPMC shine:
\[C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3\]n\]x
Hydroxypropyl methylcellulose nau'in cellulose ne wanda fitarwa da amfaninsa ke ƙaruwa cikin sauri.
Wani gaurayen ether ne wanda ba na ionic ba wanda aka yi da auduga mai tsafta bayan an yi alkali, ana amfani da propylene oxide da methyl chloride a matsayin wakilin etherification, ta hanyar jerin halayen. Matsakaicin maye gurbin gabaɗaya shine 1.2 ~ 2.0.
Abubuwan da ke cikinsa sun bambanta saboda bambancin rabon abubuwan da ke cikin methoxyl da abubuwan da ke cikin hydroxypropyl.
Hydroxypropyl methylcellulose yana narkewa cikin ruwan sanyi cikin sauƙi, amma zai fuskanci matsala wajen narkewa a cikin ruwan zafi. Amma zafin gelation ɗinsa a cikin ruwan zafi ya fi na methyl cellulose girma sosai. Narkewar da ke cikin ruwan sanyi kuma yana da kyau sosai idan aka kwatanta da methyl cellulose.
Dankowar hydroxypropyl methylcellulose yana da alaƙa da nauyin kwayoyin halittarsa, kuma girman nauyin kwayoyin halittar, haka nan girman dankowar. Zafin jiki kuma yana shafar dankowar sa, yayin da zafin jiki ke ƙaruwa, dankowar yana raguwa. Duk da haka, babban dankowar sa yana da ƙarancin tasirin zafin jiki fiye da methyl cellulose. Maganin sa yana da karko idan aka adana shi a zafin jiki na ɗaki.
Rikewar ruwa na hydroxypropyl methylcellulose ya dogara da adadin ƙarinsa, dankonsa, da sauransu, kuma yawan riƙewar ruwa a daidai adadin ƙarinsa ya fi na methyl cellulose girma.
Hydroxypropyl methylcellulose yana da daidaito ga acid da alkali, kuma ruwan da ke cikinsa yana da daidaito sosai a cikin pH = 2 ~ 12. Caustic soda da ruwan lemun tsami ba su da wani tasiri sosai a kan aikinsa, amma alkali na iya hanzarta narkewarsa da kuma ƙara dankonsa.
Hydroxypropyl methylcellulose yana da daidaito idan aka kwatanta da gishirin da aka saba samu, amma idan yawan gishirin ya yi yawa, danko na sinadarin hydroxypropyl methylcellulose yana ƙaruwa.
Ana iya haɗa Hydroxypropyl methylcellulose da mahaɗan polymer masu narkewa cikin ruwa don samar da mafita mai kama da juna kuma mafi girma. Kamar polyvinyl alcohol, sitaci ether, kayan lambu gum, da sauransu.
Hydroxypropyl methylcellulose yana da juriya ga enzyme fiye da methylcellulose, kuma maganin sa ba shi da yuwuwar ya lalace ta hanyar enzyme fiye da methylcellulose.
Lokacin Saƙo: Fabrairu-14-2023