Focus on Cellulose ethers

Indlela yohlalutyo lweepropati ze-physicochemical ze-cellulose ether

Indlela yohlalutyo lweepropati ze-physicochemical ze-cellulose ether

Umthombo, isakhiwo, iipropati kunye nokusetyenziswa kwe-cellulose ether zaziswa. Ngenxa yovavanyo lwesalathisi sepropathi ye-physicochemical yomgangatho woshishino lwe-cellulose ether, indlela esulungekisiweyo okanye ephuculweyo yabekwa phambili, kwaye ukwenzeka kwayo kwahlalutywa ngokuvavanywa.

Amagama angundoqo:i-cellulose ether; Iimpawu zomzimba kunye neekhemikhali; Indlela yohlalutyo; Ukubuza ngovavanyo

 

I-Cellulose yeyona ndawo ininzi yepolymer yendalo emhlabeni. Uluhlu lwee-derivatives lunokufumaneka ngokuguqulwa kweekhemikhali ze-cellulose. I-cellulose ether yimveliso ye-cellulose emva kwe-alkalization, i-etherification, ukuhlamba, ukuhlanjululwa, ukugaya, ukomisa kunye namanye amanyathelo. Izinto ezingundoqo ze-cellulose ether yi-cotton, i-kapok, i-bamboo, i-wood, njl., phakathi kwayo umxholo we-cellulose kumqhaphu uphezulu, ukuya kuthi ga kwi-90 ~ 95%, yinto efanelekileyo yokuvelisa i-cellulose ether, kwaye i-China ilizwe elikhulu lemveliso yomqhaphu, ekwakhuthaza nophuhliso lweshishini le-ether cellulose yaseTshayina ukuya kumlinganiselo othile. Okwangoku, ukuveliswa, ukusetyenzwa kunye nokusetyenziswa kwefiber ether kukhokela ihlabathi.

I-cellulose ether ekutyeni, amayeza, izithambiso, izinto zokwakha, iphepha, kunye namanye amashishini anoluhlu olubanzi lwezicelo. Ineempawu ze-solubility, i-viscosity, ukuzinza, ukungabi nabutyhefu kunye ne-biocompatibility. Umgangatho wovavanyo lwe-cellulose etere JCT 2190-2013, kubandakanywa ukucoceka kwe-etere ye-cellulose, ireyithi yokulahleka kwesisindo esomileyo, uthuthu lwesulfate, i-viscosity, ixabiso le-pH, ukuhanjiswa kunye nezinye izikhombisi zomzimba kunye nemichiza. Nangona kunjalo, xa i-cellulose ether isetyenziswe kumashishini ahlukeneyo, ngaphezu kohlalutyo lomzimba kunye neekhemikhali, umphumo wesicelo se-cellulose ether kule nkqubo unokuvavanywa ngakumbi. Umzekelo, ukugcinwa kwamanzi kwishishini lokwakha, ukwakhiwa kodaka, njl.; Ukubambelela kwishishini lokuncamathelisa, ukuhamba, njl.; Ukushukuma kwemihla ngemihla kushishino lweekhemikhali, ukunamathela, njl. Uhlalutyo lomzimba kunye neekhemikhali ze-cellulose ether ziyimfuneko kwimveliso, ukusetyenzwa okanye ukusetyenziswa. Ngokusekelwe kwi-JCT 2190-2013, eli phepha liphakamisa amacebo amathathu okucoca okanye okuphucula uhlalutyo lweempawu ze-physicochemical ze-cellulose ether, kwaye ziqinisekisa ukuba zinokwenzeka ngokusebenzisa iimvavanyo.

 

1. Izinga lokulahleka kwesisindo esomileyo

Ukomisa izinga lokulahleka kwesisindo sesona salathisi se-cellulose ether, ebizwa ngokuba ngumxholo womswakama, ohambelana namacandelo asebenzayo, ubomi beshelufu njalo njalo. Indlela yokuvavanya esemgangathweni yindlela yobunzima be-oven: Malunga neesampulu ze-5g zaye zalinganiswa kwaye zafakwa kwibhotile enobunzulu obungadlulanga kwi-5mm. I-cap cap yafakwa phantsi kwi-oven, okanye i-cap cap ivuliwe kwaye yomiswa kwi-105 ° C ± 2 ° C nge-2 h. Emva koko i-cap cap ikhutshwe kwaye ipholile kwiqondo lokushisa kwi-dryer, ilinganiswe, kwaye yomiswe kwi-oven ye-30 min.

Kuthatha i-2 ~ 3 iiyure ukufumana umxholo wokufuma wesampulu ngale ndlela, kwaye umxholo wokufuma uhambelana nezinye izalathisi kunye nokulungiswa kwesisombululo. Izalathisi ezininzi zinokuqhutywa kuphela emva kokuba uvavanyo lokunyakama lugqityiwe. Ngoko ke, le ndlela ayifanelekanga ekusebenziseni okusebenzayo kwiimeko ezininzi. Umzekelo, umgca wemveliso wezinye iifektri ze-cellulose ether kufuneka zibone umthamo wamanzi ngokukhawuleza, ngoko banokusebenzisa ezinye iindlela zokubona umthamo wamanzi, njengemitha yokufuma ekhawulezayo.

Ngokwendlela yokukhangela isiqulatho sokufuma esisemgangathweni, ngokuhambelana namava ovavanyo angaphambili, ngokuqhelekileyo kufuneka ukuba umise isampulu ibe nobunzima obungaguqukiyo kwi-105℃, 2.5h.

Iziphumo zovavanyo lwesiqulatho sokufuma se-cellulose ether ezahlukeneyo phantsi kweemeko ezahlukeneyo zovavanyo. Ingabonwa ukuba iziphumo zovavanyo lwe-135℃ kunye ne-0.5 h zisondele kakhulu kwezo zendlela esemgangathweni kwi-105℃ kunye ne-2.5h, kwaye ukuphambuka kweziphumo zemitha yokufuma ngokukhawuleza kukhulu. Emva kokuba iziphumo zovavanyo ziphume, iimeko ezimbini zokufumanisa i-135 ℃, i-0.5 h kunye ne-105 ℃, i-2.5 h yendlela eqhelekileyo iqhutyelwe ukubonwa ixesha elide, kwaye iziphumo azizange zihluke kakhulu. Ke ngoko, indlela yovavanyo ye-135℃ kunye ne-0.5 h inokwenzeka, kwaye ixesha lovavanyo lokufuma linokufinyezwa malunga ne-2 h.

 

2. Uthuthu lwesulfate

I-Sulfate ash cellulose ether isalathiso esibalulekileyo, esihambelana ngqo nokubunjwa kwayo okusebenzayo, ukucoceka kunye nokunye. Indlela yovavanyo oluqhelekileyo: Yomisa isampuli kwi-105 ℃ ± 2 ℃ ukuze ugcine, ulinganise malunga ne-2 g yesampulu kwi-crucible etshiswe ngokuthe tye kunye nobunzima obuqhubekayo, beka i-crucible kwipleyiti yokufudumeza okanye kwiziko lombane kunye nokufudumala ngokukhawuleza de isampuli. i-carbonized ngokupheleleyo. Emva kokupholisa i-crucible, i-2 ml egxininisiweyo ye-sulfuric acid yongezwa, kwaye i-residu ixutywe kwaye ishushu ngokukhawuleza kuze kube yilapho kubonakala umsi omhlophe. I-crucible ifakwe kwi-furnace ye-Muffle kwaye itshiswe kwi-750 ° C ± 50 ° C kwi-1 h. Emva kokutshisa, i-crucible ithathwa kwaye ipholile kwiqondo lokushisa kwi-dryer kwi-dryer kwaye ilinganiswe.

Ingabonwa ukuba indlela eqhelekileyo isebenzisa inani elikhulu le-asidi ye-sulfuric egxininisiweyo kwinkqubo yokutshisa. Emva kokufudumeza, umsi omkhulu we-volatized concentrated concentrated sulfuric acid. Nokuba iqhutywa kwi-fume hood, iya kuba nefuthe elibi kokusingqongileyo ngaphakathi nangaphandle kwelebhu. Kweli phepha, ii-ethers ze-cellulose ezahlukeneyo zisetyenziselwa ukufumanisa umlotha ngokuhambelana nendlela eqhelekileyo ngaphandle kokongeza i-sulfuric acid concentrated, kwaye iziphumo zovavanyo zifaniswa nendlela eqhelekileyo eqhelekileyo.

Kungabonwa ukuba kukho i-gap ethile kwiziphumo zokufumanisa iindlela ezimbini. Ngokusekelwe kule datha yangaphambili, iphepha libala i-gap multiple of the two in the range of 1.35 ~ 1.39. Oko kukuthi, ukuba isiphumo sovavanyo lwendlela ngaphandle kwe-asidi ye-sulfuric yandiswe yi-coefficient ye-1.35 ~ 1.39, umphumo wokuvavanya umlotha kunye ne-asidi ye-sulfuric inokufumaneka ngokukhawuleza. Emva kokuba iziphumo zovavanyo zikhutshwe, iimeko ezimbini zokufumanisa zifaniswa ixesha elide, kwaye iziphumo zahlala zincinci kule coefficient. Ibonisa ukuba le ndlela ingasetyenziselwa ukuvavanya i-ether ash ye-cellulose ecocekileyo. Ukuba kukho iimfuno ezikhethekileyo zomntu ngamnye, kufuneka kusetyenziswe indlela eqhelekileyo. Ekubeni i-ether ye-cellulose eyinkimbinkimbi yongeza izinto ezahlukeneyo, ayiyi kuxoxwa apha. Kulawulo lomgangatho we-cellulose ether, ukusebenzisa indlela yokuvavanya uthuthu ngaphandle kwe-asidi yesulfuric egxininisiweyo kunokunciphisa ungcoliseko ngaphakathi nangaphandle kwelebhu, ukunciphisa ixesha lovavanyo, ukusetyenziswa kwe-reagent kunye nokunciphisa iingozi zengozi ezinokuthi zenziwe yinkqubo yovavanyo.

 

3, i-cellulose ether yomxholo weqela lovavanyo lonyango lwangaphambili

Umxholo weqela ungenye yezalathisi ezibalulekileyo ze-cellulose ether, echaza ngokuthe ngqo iipropati zekhemikhali ze-cellulose ether. Uvavanyo lomxholo weqela libhekiselele kwi-ether ye-cellulose phantsi kwesenzo se-catalyst, ukufudumeza kunye nokuqhekeka kwi-reactor evaliweyo, kwaye emva koko ukukhutshwa kwemveliso kunye nenaliti kwi-chromatograph yegesi yohlalutyo lobungakanani. Inkqubo yokufudumeza yokuqhekeka komxholo weqela ibizwa ngokuba ngunyango lwangaphambili kweli phepha. Indlela eqhelekileyo yonyango yangaphambili yile: linganisa i-65mg yesampuli eyomileyo, yongeza i-35mg i-adipic acid kwibhotile yokusabela, ukufunxa i-3.0ml yangaphakathi yolwelo lwangaphakathi kunye ne-2.0ml ye-hydroiodic acid, yehla kwibhotile yokusabela, igubungele ngokuqinileyo kwaye ilinganise. Vuthulula ibhotile yokusabela ngesandla kwi-30s, beka ibhotile yokusabela kwi-thermostat yensimbi kwi-150 ℃ ± 2℃ ye-20min, uyikhuphe kwaye uyihlukumeze i-30S, kwaye uyifudumeze i-40min. Emva kokupholisa kwiqondo lokushisa, ukulahlekelwa kwesisindo kuyadingeka ukuba kungabi ngaphezu kwe-10mg. Ngaphandle koko, isisombululo sesampuli kufuneka silungiswe kwakhona.

Indlela eqhelekileyo yokufudumeza isetyenziswa kwi-metal thermostat yokufudumeza ukusabela, ekusetyenzisweni okwenyani, umahluko weqondo lobushushu kumqolo ngamnye webhafu yentsimbi mkhulu, iziphumo zibi kakhulu ukuphinda-phinda, kwaye ngenxa yokuba ukusabela kokuqhekeka kokufudumeza kubi kakhulu, rhoqo ngenxa yokuba ibhotile yokusabela ikepusi ayivuzi ngokungqongqo kunye nokuvuza kwegesi, kukho umngcipheko othile. Kweli phepha, ngovavanyo lwexesha elide kunye nokuqwalaselwa, indlela yonyango lwangaphambili iguqulwa ibe: kusetyenziswa ibhotile yeglasi yokuphendula, kunye neplagi yerabha yebutyl ngokuqinileyo, kunye netape yepolypropylene enganyangekiyo kubushushu isonge ujongano, emva koko ubeke ibhotile yokusabela kwisilinda esikhethekileyo esincinci. , ikhava ngokuqinileyo, ekugqibeleni ifakwe kwi-oven yokufudumala. Ibhotile yokusabela ngale ndlela ayiyi kuvuza ulwelo okanye umoya, kwaye ikhuselekile kwaye kulula ukuyisebenzisa xa i-reagent ishukunyiswa kakuhle ngexesha lokuphendula. Ukusetyenziswa kombane wokutshisa ukufudumala kwe-oven kunokwenza isampuli nganye ifudumale ngokulinganayo, umphumo kukuphindaphinda okulungileyo.

 

4. Isishwankathelo

Iziphumo zovavanyo zibonisa ukuba iindlela eziphuculweyo zokubona i-cellulose ether ekhankanywe kweli phepha zinokwenzeka. Ukusebenzisa iimeko kweli phepha ukuvavanya izinga lokumisa ukulahleka kwesisindo kunokuphucula ukusebenza kakuhle kunye nokunciphisa ixesha lokuvavanya. Ukusebenzisa akukho sulfuric acid test ukutsha uthuthu, kunokunciphisa ungcoliseko elebhu; Indlela ye-oven esetyenziswe kweli phepha njengendlela yokulungiswa kwangaphambili kwe-cellulose ether yovavanyo lomxholo weqela ingenza unyango lwangaphambili lusebenze ngakumbi kwaye lukhuselekile.


Ixesha lokuposa: Feb-14-2023
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