Kev sib txuas ntawm titanate coupling agents yog ib kauj ruam tseem ceeb hauv kev ua tiav lawv cov khoom ua haujlwm. Kev tsim kho ntawm lawv cov qauv molecular nyob ntawm qhov sib txuam ntawm cov khoom siv raw xaiv, cov txheej txheem tshuaj tiv thaiv, thiab cov txheej txheem txheej txheem. Tam sim no, feem ntau siv cov txheej txheem kev lag luam thiab kev sim tshuaj hluavtaws feem ntau yog tig mus ncig titanium qhov chaw ua kom, esterification cov tshuaj tiv thaiv, thiab tom qab- ua kom huv. Cov kev sib txawv muaj lawv tus kheej cov yam ntxwv ntawm cov khoom tsim, tawm los, thiab kev hloov pauv ntawm daim ntawv thov.
Txoj kev siv hluav taws xob tseem ceeb pib nrog tetravalent titanium tebchaw, feem ntau xws li tetraisopropyl titanate, tetrabutyl titanate, lossis titanium tetrachloride. Ntawm cov no, alkoxide titanium qhov chaw yog cov khoom siv dav tshaj plaws vim lawv qhov nruab nrab reactivity thiab yooj yim sib cais ntawm byproducts. Cov txheej txheem hluavtaws feem ntau muaj ob kauj ruam: ua ntej, kho qhov chaw sib koom ua ke ntawm titanium qhov chaw los ntawm alcoholysis los yog hydrolysis los tswj cov naj npawb ntawm alkoxy pawg nyob ib ncig ntawm titanium atoms thiab zam kev tsim ntxov ntxov ntawm inert gels; Tom qab ntawd, dhau mus rau transesterification nrog fatty acids, phosphate esters, los yog chelating tus neeg sawv cev los qhia txog lub hom phiaj ester saw ntu thiab cov pab pawg neeg ua haujlwm. Piv txwv li, monoalkoxy titanates feem ntau koom nrog reacting tetraalkyl titanate nrog ntev - chain fatty acids nyob rau hauv ib tug inert cua, tsav lub equilibrium ntawm cov khoom los ntawm tshem me me - molecule cawv. Chelating hom xav tau kev qhia txog cov neeg ua haujlwm chelating xws li -diketones los ua kom ruaj khov tsib- lossis rau - cov qauv nplhaib hauv qab alkaline catalysis, txhim kho cov khoom tiv thaiv dej.
Kev tswj cov tshuaj tiv thaiv kab mob ncaj qha cuam tshuam rau qhov tsis tu ncua thiab purity ntawm cov qauv molecular. Kub yuav tsum tau hloov kho raws li qhov kev ua ntawm titanium qhov chaw: tetraisopropyl titanate thiab cov ntaub ntawv zoo sib xws yog cov reactive heev thiab tsim nyog rau qis - kub tshwm sim ntawm 60-80℃kom txo hydrolysis; titanium tetrachloride yog qhov muaj zog heev thiab yuav tsum tau ua ntej - tshwm sim nrog cawv ntawm qhov kub thiab txias (0-5 degree) los tsim cov nruab nrab ua ntej maj mam nce qhov kub kom ua tiav esterification. Kev xaiv ntawm catalyst kuj tseem ceeb heev. Acid catalysts (xws li p-toluenesulfonic acid) tuaj yeem ua kom lub cev hloov pauv yooj yim tab sis yooj yim ua rau over-protonation ntawm titanium chaw; alkaline catalysts (xws li triethylamine) muaj txiaj ntsig zoo rau kev tswj xyuas cov qauv tetracoordinate ntawm titanium thiab tsim nyog rau kev sib txuas cov khoom chelated. Tsis tas li ntawd, cov tshuaj tiv thaiv yuav tsum nruj me ntsis cais tawm ntawm cov dej noo, feem ntau siv molecular sieve dehydration los yog nitrogen tiv thaiv los tiv thaiv titanium los ntawm hydrolyzing thiab tsim inactive titanium dioxide precipitate.
Tshaj tawm - cov txheej txheem kho mob txhawm rau tshem tawm cov khoom siv tsis zoo, cov khoom lag luam me me, thiab cov kab hlau ions. Cov txheej txheem ib txwm muaj xws li lub tshuab nqus tsev distillation kom tshem tawm cov cawv ntau dhau, ua raws li kev ntxuav dej los yog cov kua qaub tsis muaj zog kom tshem tawm cov khoom seem seem, thiab thaum kawg decolorization nrog cov pa roj carbon activated thiab ziab nrog molecular sieves kom tau txais cov khoom siab tshaj -purity. Rau cov pab pawg thermosensitive functional (xws li epoxy pawg), qhov ziab ziab yuav tsum tau tswj (tsawg dua lossis sib npaug li 60 degree) kom tsis txhob decomposition.
Kev xaiv ntawm cov txheej txheem hluavtaws sib txawv yuav tsum muaj qhov sib npaug ntawm cov khoom lag luam thiab cov kev xav tau ntawm daim ntawv thov: ib qho - cov txheej txheem cov kauj ruam yog qhov yooj yim thiab tsis tshua muaj nqi - tus nqi, tsim rau loj - nplai ntau lawm ntawm - lub hom phiaj coupling agents; cov txheej txheem stepwise tso cai rau kev tswj hwm cov qauv molecular, ua rau lawv tsim nyog rau kev kho kom haum xeeb ntawm siab -kev ua tau zoo tshwj xeeb coupling agents. Nrog rau kev nkag siab ntawm cov tswv yim ntsuab chemistry, cov thev naus laus zis tshiab xws li hnyav- cov tshuaj tiv thaiv dawb thiab bio-raws li cov khoom siv raw hloov tau maj mam siv rau titanate ester synthesis, muab txoj hauv kev tshiab rau kev lag luam kev txhim kho kom ruaj khov.
