Hloov cov neeg uas muaj kev cuam tshuam ntawm lub xov tooj ntawm tes yog ib pab pawg ntawm ntau yam thiab kev lag luam tseem ceeb muab los ntawm cellulose, ib qho ntawm cov muaj txiaj ntsig loj tshaj plaws hauv ntiaj teb. Cov kev ua kom tsim txiaj tau tsim los ntawm cov pab pawg hydroxyl (-oh) ntawm cov kab mob cellulose, ua rau ntau yam khoom muaj cov khoom sib txawv thiab cov ntawv thov. Cov ntawv thov muaj ntau los ntawm cov tshuaj, khoom noj, cov khoom lag luam cov khoom ntiag tug, cov ntaub ntawv tsim tsev, textiles, thiab ntau dua.
Tus qauv ntawm cellulose:
Cellulose yog txoj kab polysaccharide tsim los ntawm cov chav dej qab zib uas txuas nrog los ntawm β-1,4-glycosidic bonds. Cov chav ua dua rov qab muaj cov pab pawg hydroxyl rau ib chav nyob, uas ua rau lub cellulose hydrophilic thiab raug rau ntau yam tshuaj lom neeg.
Synthesis ntawm nrua cov neeg muaj kev nyab xeeb:
Cov xwm txheej ntawm cov neeg hais coj ua ntawm tes tau cuam tshuam nrog kev qhia ntawm cov pab pawg sib txawv ntawm cov pawg hydroxyl ntawm lub cellulose caj qaum. Txoj kev sib xws rau synthesizing cov neeg no muaj xws li etherification thiab Esterification.
Etherification tiv thaiv muaj kev teeb tsa cov pab pawg hydroxyl nrog alkyl lossis aryl pab pawg los tsim etheres. Qhov no tuaj yeem ua tiav los ntawm cov tshuaj tiv thaiv nrog alkylal Halides, Alkyl sulfates lossis Alkyl uas muaj kev kawm nyob rau hauv cov xwm txheej tsim nyog. Feem ntau siv alkylating tus neeg sawv cev hauv cov kev tawm tsam no muaj xws li methyl chloride, ethyl chloride, thiab benzyl chloride.
Esterification, ntawm qhov tod tes, cuam tshuam nrog pab pawg hydroxyl nrog cov pab pawg acyl los ua ib pab neeg ester. Qhov no tuaj yeem ua tiav los ntawm kev tiv thaiv nrog cov acid chlorides, anhydrides lossis cov acids nyob hauv lub xub ntiag ntawm catalysts. Cov neeg sawv cev ua kom muaj acylating nyob rau hauv cov kev tawm tsam no suav nrog acetic anhydride, acetyl chloride, thiab fatty acids.
Hom hloov chaw ntawm lub cellulais cov neeg muaj kev nyab xeeb:
Methyl Cellulose (MC):
Methylcellulose yog tsim los ntawm etherification ntawm cellulose nrog methyl chloride.
Nws yog dav siv los ua cov tuab yaj ntaub, stabilizer thiab emulsifier hauv ntau yam kev lag luam suav nrog cov khoom noj suav nrog cov khoom noj, cov khoom lag luam thiab cov khoom siv saib xyuas tus kheej.
MC ua cov gel meej thaum hydrated thiab cov khoom ua kom pom tseeb tus cwj pwm, ua rau nws xav tau viscosity tswj.
Hydroxyethylcellulose (HEC):
Hydroxyethyl cellulose yog synthesized los ntawm etherification ntawm cellulose thiab ethylene oxide.
Nws yog feem ntau siv raws li cov tuab tuab, nplaum thiab cov yeeb yaj kiab-sib sau tus neeg sawv cev ua cov tshuaj tiv thaiv, tshuaj pleev ib ce, tshuaj thiab lwm yam kev lag luam thiab lwm yam khoom lag luam thiab lwm yam khoom lag luam thiab lwm yam khoom lag luam thiab lwm yam khoom lag luam.
Hec coparts pseudopastic cwj pwm rau kev daws thiab muab cov khoom siv dej zoo heev.
Hydroxypropylencellulose (HPC):
HydroxyPropyl cellulose yog tsim los ntawm etherification ntawm cellulose nrog Propylene Oxide.
Nws yog siv los ua cov tuab yaj ntaub, stabilizer thiab binder hauv tshuaj yeeb yaj kiab, tshwj xeeb hauv cov ntsiav tshuaj pleev tshuaj.
HPC muaj cov khoom siv hluav taws xob thermogelling, tsim cov kua pleev ntawm cov kub.
Carboxymethylcellulose (CMC):
Carboxymethylcellose yog synthesized los ntawm etherification ntawm cellulose ntawm cellulose thiab sodium monochloroacetate hauv Alkaline tej yam kev mob.
Nws yog dav siv ua cov tuab, stabilizer thiab emulsifier hauv cov zaub mov, chaw noj tshuaj thiab kev siv cov ntawv thov.
CMC Imparts viscoS thiab shear-thinning tus cwj pwm rau kev daws teeb meem thiab cov ntaub ntawv ruaj khov colloidal dispersion.
Ethyl Hydroxyethyl cellulose (EHEC):
Ethyl hydulose yog ib tug diseedituted cellulose cellulose cellulose cellulose sectereded ethylene oxide thiab ethyl chloride.
Nws yog siv los ua cov tuab yaj ntaub, rheology kho thiab zaj duab xis yav dhau los hauv ntau cov kev siv nrog cov tsho tiv no nrog cov khoom noj, cov khoom lag luam.
EHEC muaj ntau dua cov dej solubility thiab sib xyaw ua ke dua li nws singly hloov cov neeg ua yeeb yam.
Cov yam ntxwv ntawm cov neeg muaj kev nyab xeeb ntawm tes:
Cov yam ntxwv ntawm cov neeg muaj kev cuam tshuam ntawm tes yog cov neeg uas muaj kev sib txawv raws li cov lus qhia txog kev hloov pauv, hnyav hnyav thiab cov qauv tshuaj. Txawm li cas los xij, lawv feem ntau nthuav tawm cov yam ntxwv hauv qab no:
Hydrophilicity: hloov cellulose cellulose cov neeg muaj kev hais daws yog hydroxilic vim muaj cov qauv ntawm hydroxyl, uas tso cai rau lawv cuam tshuam nrog cov roj av molecules los ntawm hydrogen tsev.
Thickening thiab gelling: ntau nrua cov neeg muaj kev cuam tshuam ntawm cellulose muaj cov khoom siv thickening thiab gelling, ua rau muaj kev tsim cov kev daws teeb meem lossis gels rau ntawm cov dej num. Viscosity thiab gel lub zog pab raws li cov polymer concentration thiab hnyav hnyav.
Zaj duab xis tsim: Qee tus neeg muaj kev hais ua ke ntawm tes muaj peev xwm ua kom muaj cov yeeb yaj kiab ntshiab thiab hloov tau yooj yim thaum ua cov yeeb yaj kiab los ntawm kev daws. Cov cuab yeej no muaj qhov zoo hauv cov ntawv thov xws li txheej ci, cov nplaum, thiab cov khoom siv tshuaj tiv thaiv cov tshuaj.
Qhov ruaj khov: hloov cov neeg muaj kev nyab xeeb feem ntau ua rau muaj kev ruaj khov zoo dua li ntawm cov xwm txheej PH thiab kub. Lawv tiv taus microbial degradation thiab enzymatic hydrolysis, ua rau lawv haum rau siv ntau yam qauv.
Rheological tus cwj pwm: hloov cov neeg muaj kev pab cuam cellulose feem ntau ua pov thawj pseudopastic lossis shear-thij-thuav tus cwj pwm, uas txhais tau tias lawv viscosity txo qis nyob rau hauv shear kev nyuaj siab. Cov cuab yeej no yog ntshaw nyob rau hauv cov ntawv thov uas xav tau yooj yim ntawm kev ua lossis daim ntawv thov.
Cov ntawv thov ntawm cov neeg muaj kev nyab xeeb ntawm tes:
Hloov cov neeg muaj kev nyab xeeb ntawm tes yog siv dav hauv ntau kev lag luam vim lawv cov khoom muaj ntau yam. Qee daim ntawv thov tseem ceeb muaj xws li:
Kev lag luam khoom noj khoom haus: hloov cov pab pawg neeg ua haujlwm xws li thickeners, stabulizers thiab emulsifiers hauv cov khoom noj xws li cov kua ntses, hnav khaub ncaws thiab cov khoom noj khoom thiab khoom noj siv mis. Lawv txhim kho kev ntxhib los mos, ruaj khov thiab qhov ncauj qhov ncauj thaum ncua lub neej.
Kws ua cov neeg muaj kev muaj kev nyab xeeb ntawm cov kws ua yeeb yam ntawm tes yog siv nyob rau hauv cov ntsiav tshuaj, tsiav tshuaj thiab cov qauv zoo nkauj thiab cov ncauj lus. Lawv txhim kho kev xa tshuaj, Bioavailability thiab tus neeg mob ua tsaug.
Cov khoom siv saib xyuas tus kheej: hloov cellulose cellulose muaj cov khoom xyaw xws li cov tshuaj ntxuav tes ua rau lawv cov tuab yaj ntaub, tso cai thiab ua yeeb yaj kiab ua yeeb yam. Lawv txhim kho cov khoom ruaj khov, kev ntxhib los mos thiab cov kev xav pom zoo.
Cov Khoom Siv Siv: Lwm cov lus hais txog cellulose yog siv los ua cov khoom siv xws li xis mas thiab cov khoom siv gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum thiab gypsum-beltenty Thiab dej nplaum. Lawv txhim kho kev ua tau zoo thiab kav ntev ntawm cov ntaub ntawv no.
Textiles: Hloov cellulose cellulose cellulose celli luam ntawv thiab ua tiav cov txheej txheem kom muab viscosity tswj, adhesion thiab ntxuav ceev ceev. Lawv pab hauv kev tso nyiaj txawm tias dyes thiab pigments rau textile substrates.
Roj thiab roj kev lag luam: Hloov cellulose cellosifiers thiab cov kua dej poob hauv kev xyaum ua kom zoo thiab kev nyab xeeb cov roj thiab roj drilling ua haujlwm.
Lub Sijhawm Post: Feb-19-2025