A cikin turmi da aka shirya, adadin ƙarin cellulose ether yana da ƙasa sosai, amma yana iya inganta aikin turmi mai jika sosai, kuma babban ƙari ne wanda ke shafar aikin ginin turmi. Zaɓin da ya dace na ethers cellulose iri-iri, ɗanɗano daban-daban, girman barbashi daban-daban, matakan ɗanɗano daban-daban da ƙarin adadin zai yi tasiri mai kyau akan inganta aikin turmi busasshe. A halin yanzu, turmi da yawa na dutse da na filastik ba su da aikin riƙe ruwa mai kyau, kuma ruwan zai rabu bayan 'yan mintuna kaɗan na tsayawa. Rike ruwa muhimmin aiki ne na methyl cellulose ether, kuma aiki ne da yawancin masana'antun turmi busasshe na cikin gida, musamman waɗanda ke yankunan kudu masu yanayin zafi mai yawa, ke mai da hankali a kai. Abubuwan da ke shafar tasirin riƙe ruwa na turmi busasshe sun haɗa da adadin da aka ƙara na MC, ɗanɗano na MC, ɗanɗano na barbashi da zafin yanayin amfani.
1. Ra'ayi
Cellulose ether wani nau'in polymer ne da aka yi daga cellulose na halitta ta hanyar gyaran sinadarai. Cellulose ether wani nau'in cellulose ne da aka samo daga cellulose na halitta. Samar da cellulose ether ya bambanta da polymers na roba. Mafi mahimmancin kayansa shine cellulose, wani mahaɗin polymer na halitta. Saboda takamaiman tsarin cellulose na halitta, cellulose kanta ba ta da ikon yin aiki tare da wakilan etherification. Duk da haka, bayan maganin maganin kumburi, haɗin hydrogen mai ƙarfi tsakanin sarƙoƙin kwayoyin halitta da sarƙoƙi suna lalacewa, kuma sakin ƙungiyar hydroxyl mai aiki ya zama cellulose mai amsawa. Sami cellulose ether.
Halayen ethers na cellulose sun dogara ne akan nau'in, adadi da rarrabawar abubuwan maye. Rarraba ethers na cellulose kuma ya dogara ne akan nau'in abubuwan maye, matakin etherification, narkewa da halayen aikace-aikacen da suka shafi hakan. Dangane da nau'in abubuwan maye akan sarkar kwayoyin halitta, ana iya raba shi zuwa monoether da gauraye ether. MC da muke amfani da shi yawanci shine monoether, kuma HPMC gauraye ether ne. Methyl cellulose ether MC shine samfurin bayan an maye gurbin ƙungiyar hydroxyl akan sashin glucose na cellulose na halitta da methoxy. Samfuri ne da aka samu ta hanyar maye gurbin wani ɓangare na ƙungiyar hydroxyl akan naúrar tare da rukunin methoxy da wani ɓangare tare da rukunin hydroxypropyl. Tsarin tsarin shine [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethyl methyl cellulose ether HEMC, waɗannan sune manyan nau'ikan da ake amfani da su sosai kuma ana sayarwa a kasuwa.
Dangane da narkewar sinadaran, ana iya raba shi zuwa ionic da non-ionic. Ethers cellulose marasa ionic masu narkewa cikin ruwa galibi sun ƙunshi jerin alkyl ethers guda biyu da hydroxyalkyl ethers. Ana amfani da Ionic CMC galibi a cikin sabulun sabulu na roba, buga yadi da rini, binciken abinci da mai. Ana amfani da Non-ionic MC, HPMC, HEMC, da sauransu galibi a cikin kayan gini, shafa latex, magani, sinadarai na yau da kullun, da sauransu. Ana amfani da su azaman mai kauri, wakilin riƙe ruwa, mai daidaita, mai wargazawa da wakilin samar da fim.
Na biyu, riƙe ruwa na cellulose ether
Rikewar cellulose ether a cikin ruwa: A cikin samar da kayan gini, musamman busasshen turmi, cellulose ether yana taka muhimmiyar rawa, musamman a cikin samar da turmi na musamman (turmi da aka gyara), abu ne mai mahimmanci kuma mai mahimmanci.
Muhimmin rawar da cellulose ether mai narkewa a cikin turmi ke takawa a cikin turmi galibi yana da fannoni uku, ɗaya shine ingantaccen ƙarfin riƙe ruwa, ɗayan kuma shine tasirin da ke kan daidaito da thixotropy na turmi, na uku kuma shine hulɗa da siminti. Tasirin riƙe ruwa na cellulose ether ya dogara ne akan sha ruwa na layin tushe, abun da turmi ke ciki, kauri na layin turmi, buƙatar ruwa na turmi, da lokacin saita kayan saitawa. Rike ruwa na cellulose ether da kansa ya fito ne daga narkewa da bushewar cellulose ether da kanta. Kamar yadda muka sani, kodayake sarkar kwayoyin cellulose tana ɗauke da adadi mai yawa na ƙungiyoyin OH masu ruwa sosai, ba ya narkewa a cikin ruwa, saboda tsarin cellulose yana da babban matakin crystallinity.
Ikon ruwa na ƙungiyoyin hydroxyl kaɗai bai isa ya rufe ƙarfin haɗin hydrogen da ƙarfin van der Waals tsakanin ƙwayoyin ba. Saboda haka, yana kumbura kawai amma ba ya narkewa a cikin ruwa. Lokacin da aka shigar da wani madadin cikin sarkar ƙwayoyin halitta, ba wai kawai madadin yana lalata sarkar hydrogen ba, har ma haɗin hydrogen na interchain yana lalacewa saboda haɗin madadin tsakanin sarƙoƙi maƙwabta. Mafi girman madadin, mafi girman nisa tsakanin ƙwayoyin halitta. Mafi girman nisa. Mafi girman tasirin lalata haɗin hydrogen, cellulose ether yana narkewa cikin ruwa bayan layin cellulose ya faɗaɗa kuma maganin ya shiga, yana samar da mafita mai ƙarfi. Lokacin da zafin jiki ya tashi, ruwan polymer ɗin yana rauni, kuma ruwan da ke tsakanin sarƙoƙi yana fitar da shi. Lokacin da tasirin bushewa ya isa, ƙwayoyin suna fara taruwa, suna samar da gel mai girma uku kuma suna naɗewa.
Abubuwan da ke shafar riƙe ruwa na turmi sun haɗa da danko na cellulose ether, adadin ƙari, ƙarancin barbashi da zafin amfani:
Girman danko na cellulose ether, haka nan ingancin aikin riƙe ruwa yake. Danko muhimmin ma'auni ne na aikin MC. A halin yanzu, masana'antun MC daban-daban suna amfani da hanyoyi da kayan aiki daban-daban don auna danko na MC. Manyan hanyoyin sune Haake Rotovisko, Hoppler, Ubbelohde da Brookfield. Ga samfurin iri ɗaya, sakamakon danko da aka auna ta hanyoyi daban-daban ya bambanta sosai, kuma wasu ma suna da bambance-bambance ninki biyu. Saboda haka, lokacin kwatanta danko, dole ne a yi shi tsakanin hanyoyin gwaji iri ɗaya, gami da zafin jiki, rotor, da sauransu.
Gabaɗaya dai, idan girman danko ya yi yawa, to tasirin riƙe ruwa zai fi kyau. Duk da haka, idan girman danko ya yi yawa da kuma girman nauyin kwayoyin halitta na MC, raguwar narkewar sa zai yi mummunan tasiri ga ƙarfi da aikin ginin turmi. Yayin da girman danko ya yi yawa, to tasirin kauri a turmi zai bayyana, amma ba daidai yake ba. Yayin da girman danko ya yi yawa, tofin da ya yi yawa zai yi yawa, wato, yayin gini, yana bayyana a matsayin manne wa abin gogewa da kuma mannewa mai yawa ga substrate. Amma ba shi da amfani a ƙara ƙarfin tsarin turmi da ya yi yawa. A lokacin gini, aikin hana sag ba a bayyane yake ba. Akasin haka, wasu ethers na methyl cellulose masu matsakaici da ƙarancin danko amma waɗanda aka gyara suna da kyakkyawan aiki wajen inganta ƙarfin tsarin turmi da ya yi yawa.
Mafi girman adadin cellulose ether da aka ƙara a cikin turmi, mafi kyawun aikin riƙe ruwa, da kuma yawan ɗanko, mafi kyawun aikin riƙe ruwa.
Dangane da girman barbashi, gwargwadon yadda barbashi ya fi kyau, haka nan ma riƙe ruwa zai fi kyau. Bayan manyan barbashi na cellulose ether sun haɗu da ruwa, saman zai narke nan take ya samar da gel don naɗe kayan don hana ƙwayoyin ruwa ci gaba da shiga. Wani lokaci ba za a iya warwatse shi gaba ɗaya ba ko da bayan an daɗe ana juyawa, yana samar da ruwan da ke ɗauke da gajimare ko haɗuwa. Yana shafar riƙe ruwa na cellulose ether, kuma narkewa yana ɗaya daga cikin abubuwan da ke haifar da zaɓar cellulose ether.
Fineness kuma muhimmin ma'aunin aiki ne na methyl cellulose ether. Ana buƙatar MC da ake amfani da shi don busasshen turmi ya zama foda, tare da ƙarancin ruwa, kuma fineness ɗin yana buƙatar kashi 20% ~ 60% na girman barbashi ya zama ƙasa da 63um. Fineness ɗin yana shafar narkewar methyl cellulose ether. MC mai kauri yawanci yana da granular, kuma yana da sauƙin narkewa a cikin ruwa ba tare da haɗuwa ba, amma saurin narkewa yana da jinkiri sosai, don haka bai dace da amfani da shi a cikin busasshen turmi ba. A cikin busasshen turmi, MC yana warwatse tsakanin kayan siminti kamar tarawa, filler mai kyau da siminti, kuma foda mai kyau kawai zai iya guje wa haɗar methyl cellulose ether lokacin haɗawa da ruwa. Lokacin da aka ƙara MC da ruwa don narkar da agglomerates, yana da matukar wahala a warwatse da narkar da shi.
Tsantsar MC ba wai kawai ɓatarwa ba ce, har ma tana rage ƙarfin turmi na gida. Idan aka shafa irin wannan turmi busasshe a babban yanki, saurin wargaza turmi busasshe na gida zai ragu sosai, kuma tsagewa za su bayyana saboda lokutan wargazawa daban-daban. Ga turmi da aka fesa tare da ginin injiniya, buƙatar laushi ya fi girma saboda ɗan gajeren lokacin haɗawa.
Ingancin MC kuma yana da wani tasiri a kan riƙe ruwa. Gabaɗaya, ga ethers na methyl cellulose masu ɗanko iri ɗaya amma suna da ɗanko daban-daban, a ƙarƙashin adadin ƙari iri ɗaya, mafi ƙanƙanta mafi ƙanƙanta mafi kyawun tasirin riƙe ruwa.
Rikewar ruwa na MC yana da alaƙa da zafin da ake amfani da shi, kuma riƙewar ruwa na methyl cellulose ether yana raguwa tare da ƙaruwar zafin jiki. Duk da haka, a aikace-aikacen kayan aiki na gaske, ana amfani da turmi busasshe a kan abubuwan da ke da zafi a yanayin zafi mai yawa (fiye da digiri 40) a wurare da yawa, kamar shafa fenti a bango a ƙarƙashin rana a lokacin rani, wanda sau da yawa yana hanzarta Warkewa da siminti da taurare busasshen turmi. Ragewar yawan riƙe ruwa yana haifar da jin cewa ƙarfin aiki da juriyar tsagewa suna shafar, kuma yana da matuƙar mahimmanci a rage tasirin abubuwan zafin jiki a ƙarƙashin wannan yanayin.
Duk da cewa a halin yanzu ana ɗaukar ƙarin methyl hydroxyethyl cellulose ether a matsayin sahun gaba a ci gaban fasaha, dogaro da su kan zafin jiki zai haifar da raguwar aikin busasshen turmi. Duk da cewa adadin methyl hydroxyethyl cellulose ya ƙaru (tsarin bazara), ƙarfin aiki da juriyar tsagewa har yanzu ba za su iya biyan buƙatun amfani ba. Ta hanyar wasu jiyya na musamman akan MC, kamar ƙara matakin etherification, da sauransu, ana iya kiyaye tasirin riƙe ruwa a mafi yawan zafin jiki, don haka zai iya samar da ingantaccen aiki a ƙarƙashin mawuyacin yanayi.
3. Kauri da Taushi na Cellulose Ether
Kauri da kuma girman sinadarin cellulose ether: Aiki na biyu na sinadarin cellulose ether—tasirin kauri ya dogara ne akan: matakin polymerization na cellulose ether, yawan sinadarin, saurin yankewa, zafin jiki da sauran yanayi. Siffar sinadarin gel na maganin ta kebanta da sinadarin alkyl cellulose da kuma siffar da aka gyara. Siffar sinadarin gel tana da alaƙa da matakin maye gurbinsa, yawan sinadarin da kuma ƙarin sinadarai. Ga siffar sinadarin hydroxyalkyl da aka gyara, siffar sinadarin gel kuma tana da alaƙa da matakin gyara na hydroxyalkyl. Ga siffar sinadarin MC da HPMC da aka rage, ana iya shirya siffar sinadarin 10%-15%, matsakaicin danko MC da HPMC za a iya shirya siffar sinadarin 5%-10%, yayin da babban danko MC da HPMC za su iya shirya siffar sinadarin 2%-3% kawai, kuma yawanci ana kimanta siffar sinadarin cellulose ether da kashi 1%-2%.
Babban sinadarin cellulose ether mai nauyin kwayoyin halitta yana da ingantaccen kauri. A cikin wannan maganin tattarawa, polymers masu nauyin kwayoyin halitta daban-daban suna da bambance-bambancen viscosities. Babban mataki. Ana iya cimma dankowar da aka nufa ne kawai ta hanyar ƙara yawan cellulose ether mai nauyin kwayoyin halitta. Dankowar sa ba ta dogara sosai kan yawan yankewa ba, kuma babban dankowar ya kai dankowar da aka nufa, kuma adadin da ake buƙata na ƙarin yana da ƙarami, kuma dankowar ya dogara ne akan ingancin kauri. Saboda haka, don cimma daidaito, dole ne a tabbatar da wani adadin cellulose ether (tattarawar maganin) da dankowar mafita. Zafin gel na maganin kuma yana raguwa a layi tare da ƙaruwar yawan maganin, da kuma gels a zafin ɗaki bayan ya kai wani adadin. Yawan gelling na HPMC yana da yawa a zafin ɗaki.
Haka kuma ana iya daidaita daidaito ta hanyar zaɓar girman barbashi da zaɓar ƙwayoyin cellulose masu matakai daban-daban na gyare-gyare. Abin da ake kira gyare-gyare shine gabatar da wani mataki na maye gurbin ƙungiyoyin hydroxyalkyl akan tsarin kwarangwal na MC. Ta hanyar canza ƙimar maye gurbin dangi na ƙungiyoyin biyu, wato, ƙimar maye gurbin dangi na DS da ms na ƙungiyoyin methoxy da hydroxyalkyl waɗanda muke yawan faɗi. Ana iya samun buƙatun aiki daban-daban na cellulose ether ta hanyar canza ƙimar maye gurbin dangi na maye gurbin biyu.
Alaƙa tsakanin daidaito da gyare-gyare: ƙara cellulose ether yana shafar yawan turmi, canza rabon ruwa da siminti shine tasirin kauri, mafi girman adadin, mafi girman yawan amfani da ruwa.
Dole ne ƙwayoyin cellulose da ake amfani da su a cikin kayan gini na foda su narke da sauri a cikin ruwan sanyi kuma su samar da daidaito mai dacewa ga tsarin. Idan aka ba da wani takamaiman matakin yankewa, har yanzu yana zama toshewar flocculent da colloidal, wanda samfuri ne mara inganci ko mara inganci.
Akwai kuma kyakkyawar alaƙa tsakanin daidaiton manna siminti da kuma yawan sinadarin cellulose ether. Cellulose ether na iya ƙara yawan sinadarin turmi sosai. Mafi girman yawan sinadarin, haka nan tasirin yake bayyana. Maganin ruwa mai ƙarfi na cellulose ether yana da yawan sinadarin thixotropy, wanda kuma babban siffa ne na cellulose ether. Maganin ruwa na polymers na MC yawanci suna da sinadarin pseudoplastic da wanda ba shi da sinadarin thixotropic a ƙasa da zafin gel ɗinsu, amma halayen kwararar Newtonian a ƙarancin saurin yankewa. Pseudoplasticity yana ƙaruwa tare da nauyin kwayoyin halitta ko yawan sinadarin cellulose ether, ba tare da la'akari da nau'in sinadarin da kuma matakin maye gurbinsa ba. Saboda haka, ƙwayoyin cellulose masu irin wannan yanayin ɗanko, komai MC, HPMC, HEMC, za su nuna irin wannan yanayin rheological matuƙar yawan sinadarin da zafin jiki suna nan a tsaye.
Ana samar da gels na tsari lokacin da aka ɗaga zafin jiki, kuma kwararar thixotropic mai yawa tana faruwa. Babban taro da ƙarancin ɗanko na cellulose ethers suna nuna thixotropy ko da ƙasa da zafin gel. Wannan kadara tana da babban fa'ida ga daidaitawar daidaitawa da raguwa a cikin ginin turmi. Ya kamata a yi bayani a nan cewa mafi girman ɗanko na cellulose ether, mafi kyawun riƙe ruwa, amma mafi girman ɗanko, mafi girman nauyin ƙwayoyin cellulose ether, da raguwar narkewar sa, wanda ke da mummunan tasiri akan yawan turmi da aikin gini. Mafi girman ɗanko, mafi girman tasirin kauri akan turmi, amma ba cikakke bane. Wasu matsakaici da ƙarancin ɗanko, amma cellulose ether da aka gyara yana da mafi kyawun aiki wajen inganta ƙarfin tsarin turmi mai danshi. Tare da ƙaruwar ɗanko, riƙewar ruwa na cellulose ether yana inganta. 4. Ragewar cellulose ether
Ragewar sinadarin cellulose ether: Aiki na uku na sinadarin cellulose ether shine jinkirta tsarin sinadarin siminti. Cellulose ether yana ba da turmi da wasu fa'idodi masu amfani, kuma yana rage zafin siminti da wuri kuma yana jinkirta tsarin sinadarin siminti. Wannan ba shi da kyau ga amfani da turmi a yankunan sanyi. Wannan tasirin ragewar yana faruwa ne sakamakon shaƙar ƙwayoyin cellulose ether akan samfuran sinadarin kamar CSH da ca(OH)2. Saboda ƙaruwar danko na maganin rami, sinadarin cellulose ether yana rage motsi na ions a cikin maganin, wanda hakan ke jinkirta tsarin sinadarin.
Lokacin Saƙo: Fabrairu-04-2023