Isitatshi ethers kunye ne-cellulose ethers zombini ii-ethers ezidlala indima ebalulekileyo kumashishini ahlukeneyo, ngakumbi kulwakhiwo kunye njengezongezo kwiimveliso ezahlukeneyo. Nangona zinokufana okuthile, zikhompawundi ezahlukeneyo ezinemichiza eyahlukeneyo, iipropathi, kunye nokusetyenziswa.
1.Ulwakhiwo lwekhemikhali:
Isitatshi ether:
Isitatshi ethers zithathwe kwi-starch, i-polysaccharide eyenziwe ngeeyunithi ze-glucose. Ubume bemichiza yesitashi buqukethe amacandelo amabini aphambili: i-amylose (i-linear chain of glucose molecules edityaniswe yi-α-1,4-glycosidic bonds) kunye ne-amylopectin (ene-α-1,4 kunye ne-α-1,6- iipolymers ezinamagatsha ane-glycosidic bond. ) uqhagamshelwano. Ii-ethers zesitatshi zifunyanwa ngokuguqula amaqela e-hydroxyl esitatshi ngenkqubo ye-etherification.
Iselulosi ether:
Ngakolunye uhlangothi, i-cellulose yenye i-polysaccharide, kodwa isakhiwo sayo siqukethe iiyunithi ze-glucose ezidityaniswe ngamabhondi e-β-1,4-glycosidic. I-ethers ye-cellulose ithathwe kwi-cellulose ngokusebenzisa inkqubo ye-etherification efanayo. Iiyunithi eziphindaphindayo kwi-cellulose zidibaniswe ngamabhondi e-beta, ezenza i-linear kunye ne-crystalline structure.
2. Umthombo:
Isitatshi ether:
Isitatshi siphuma ikakhulu kwizityalo ezifana nombona, ingqolowa kunye neetapile. Ezi zityalo zizidama zestatshi kunye nesitatshi ethers zinokukhutshwa kwaye zilungiswe.
Iselulosi ether:
I-Cellulose iyona nxalenye ephambili yeendonga zeeseli zesityalo kwaye ikhona ngokubanzi kwindalo. Imithombo eqhelekileyo ye-cellulose ibandakanya i-pulp yomthi, umqhaphu, kunye nemicu yezityalo ezahlukeneyo. I-cellulose ethers iveliswa ngokuguqula iimolekyuli ze-cellulose ezithathwe kule mithombo.
3. Inkqubo ye-Etherification:
Isitatshi ether:
Inkqubo ye-etherification yestatshi ibandakanya ukuqaliswa kwamaqela e-ether kumaqela e-hydroxyl (OH) akhoyo kwiimolekyuli zestatshi. Amaqela e-ether aqhelekileyo ongeziweyo aquka i-methyl, i-ethyl, i-hydroxyethyl, kunye ne-hydroxypropyl, okubangelwa utshintsho kwiipropati zesitashi esilungisiweyo.
Iselulosi ether:
I-Etherification ye-cellulose ibandakanya inkqubo efanayo apho amaqela e-ether angeniswa kumaqela e-hydroxyl ye-cellulose. Izinto eziqhelekileyo ze-cellulose ether derivatives ziquka i-methylcellulose, i-ethylcellulose, i-hydroxyethylcellulose kunye ne-carboxymethylcellulose.
4. Ukunyibilika:
Isitatshi ether:
Ii-ethers zesitatshi ngokubanzi zinokunyibilika okuphantsi kwamanzi kuneether ze-cellulose. Ngokuxhomekeke kwiqela elithile le-ether eliqhotyoshelweyo ngexesha lokuguqulwa, banokubonisa amanqanaba ahlukeneyo okunyibilika.
Iselulosi ether:
I-cellulose ethers iyaziwa ngokuba yi-ether-soluble okanye i-water-dispersible properties. Ukunyibilika kuxhomekeke kuhlobo kunye neqondo lokutshintshwa kwe-ether.
5. Ukwenza ifilimu:
Isitatshi ether:
Ii-ethers zesitatshi ngokubanzi zinesakhono esilinganiselweyo sokwenza ifilim ngenxa yendalo yazo eyi-semi-crystalline. Ifilimu ephumayo inokuthi ingabonakali kwaye ingabi bhetyebhetye kuneefilimu ezenziwe kwi-cellulose ethers.
Iselulosi ether:
I-cellulose ethers, ngokukodwa izinto eziphuma kwi-methylcellulose, ziyaziwa ngeempawu zazo ezibalaseleyo zokwenza ifilimu. Bangakwazi ukudala iifilimu ezicacileyo kunye neziguquguqukayo, okwenza ukuba zixabiseke kwizicelo ezifana neengubo kunye ne-adhesives.
6.Iimpawu zeRheological:
Isitatshi ether:
Isitashi se-ethers sinokunyusa i-viscosity yezisombululo ezinamanzi, kodwa ukuziphatha kwabo kwe-rheological kunokwahluka kwi-cellulose ethers. Impembelelo kwi-viscosity ixhomekeke kwizinto ezifana neqondo lokuthatha indawo kunye nobunzima bemolekyuli.
Iselulosi ether:
I-cellulose ethers ziyaziwa ngokubanzi ngezakhono zabo zokulawula i-rheology. Zinokuchaphazela kakhulu i-viscosity, ukugcinwa kwamanzi kunye nokuhamba kweempawu kwiinkqubo ezahlukeneyo ezibandakanya iipeyinti, i-adhesives kunye nezinto zokwakha.
7. Isicelo:
Isitatshi ether:
Isitatshi se-ethers sinokusetyenziswa kumashishini okutya, amalaphu kunye namayeza. Kwishishini lokwakha, zisetyenziselwa udaka, i-plasters kunye ne-adhesives ukunyusa iipropati ezifana nokugcinwa kwamanzi kunye nokusebenza.
Iselulosi ether:
I-cellulose ethers isetyenziswa ngokubanzi kumayeza, ukutya, izimonyo kunye nemimandla yokwakha. Zisetyenziswa ngokubanzi njengama-thickeners, i-stabilizers kunye ne-rheology modifiers kwiipende, i-mortars, i-adhesives ye-tile kunye neendlela ezahlukeneyo zokuqulunqa.
8. Ukonakala kwezinto eziphilayo:
Isitatshi ether:
Isitatshi ethers zisuka kwizityalo kwaye zidla ngokubola. Banceda ukwandisa ukuzinza kweemveliso ezisetyenzisiweyo.
Iselulosi ether:
I-cellulose ethers evela kwi-cellulose yesityalo nayo iyakwazi ukubola. Ukuhambelana kwabo kokusingqongileyo kuyinzuzo ephambili kwizicelo apho ukuzinza kuyinto ephambili.
ukuququmbela:
Nangona i-starch ethers kunye ne-cellulose ethers zabelana ngezinto eziqhelekileyo njenge-polysaccharide derivatives, izakhiwo zabo zeekhemikhali ezikhethekileyo, imithombo, i-solubility, iipropati zokwenza ifilimu, ukuziphatha kwe-rheological kunye nezicelo zibeke bucala ukuze zisetyenziswe kwiinkalo ezahlukeneyo. Isitatshi se-ethers esivela kwisitatshi kunye ne-cellulose ethers evela kwiselulosi nganye ineenzuzo ezizodwa kwiimeko ezahlukeneyo. Ukuqonda lo mahluko kubalulekile ekukhetheni i-ether efanelekileyo kwisicelo esithile, ukuqinisekisa ukusebenza kakuhle kunye neempawu ezifunwayo.
Ixesha lokuposa: Jan-25-2024