Titanate coupling agents yog ib chav kawm ntawm kev ua hauj lwm additives nrog tetravalent titanium atoms ua lub hauv paus, bridging inorganic fillers thiab organic polymers los ntawm ester pawg. Lawv tus nqi tseem ceeb nyob rau hauv kev daws teeb meem interfacial incompatibility ntawm ob yam khoom uas muaj ntau yam sib txawv. Lawv cov txheej txheem ntawm kev txiav txim yog cov hauv paus hauv kev tsim qauv ntawm cov qauv molecular thiab kev sib koom ua ke ntawm kev cuam tshuam ntawm kev sib cuam tshuam, thiab tuaj yeem txheeb xyuas los ntawm peb theem: kev sib txuas tshuaj, lub cev ntub dej, thiab steric stability.
Raws li kev tsim qauv, titanate coupling cov neeg sawv cev muaj xws li lub hauv paus titanium atom, ester pawg ntu, thiab cov pab pawg ua haujlwm ntawm lub davhlau ya nyob twg. Lub hauv paus titanium atom (Ti⁴⁺) muaj peev xwm sib koom ua ke muaj zog, ua rau nws ua haujlwm nrog cov pawg polar xws li hydroxyl (-OH) thiab carboxyl (-COOH) pawg nyob rau saum npoo ntawm cov khoom siv inorganic lossis daim ntawv cog lus, yog li "anchoring" nws tus kheej mus rau qhov chaw muab tub lim. Ester saw segments (xws li monoalkoxy, pyrophosphate, lossis chelate rings) ua raws li cov txuas txuas yooj yim, cais cov titanium chaw nruab nrab ntawm cov dej noo sab nraud kom txo tau qhov kev pheej hmoo ntawm hydrolysis, thiab kuj kho qhov sib cuam tshuam thickness los ntawm steric hindrance. Terminal functional pab pawg (ntev-chain alkyl, aromatic, los yog reactive pawg) yog lub luag hauj lwm rau compatibility nrog cov organic polymer matrix-non- pawg polar entangle nrog hydrophobic resin los ntawm van der Waals rog, thaum polar los yog reactive pawg koom ua ke rau hauv cov organic network los ntawm hydrogen bonding, π {8} sib txuas lus kawg, π { tsim ib txheej txuas txuas ntxiv ntawm "inorganic filler-coupling agent-organic matrix."
Cov txheej txheem yuav muab faib ua peb kauj ruam: Ua ntej, lub cev adsorption, qhov twg coupling tus neeg sawv cev molecules spontaneously adsorb vim muaj kev sib cuam tshuam ntawm lawv cov polarity thiab cov hydroxyl pawg ntawm cov muab tub lim; Thib ob, kev sib koom ua ke tshuaj, qhov chaw titanium ua rau lub cev qhuav dej los yog kev sib koom ua ke nrog cov pab pawg hydroxyl nyob rau ntawm qhov chaw muab tub lim, ua kom ruaj khov Ti-O-M (M yog cov hlau muab tub lim lossis silicon atom) daim ntawv cog lus; thiab thaum kawg, cov organic compatibility, qhov twg cov pab pawg neeg ua haujlwm ntawm lub davhlau ya nyob twg thiab cov saw hlau molecular polymer ua tiav cov molecular- theem sib xyaw los ntawm kev sib kis, kev sib txuas, lossis tshuaj lom neeg. Cov txheej txheem no tsis tsuas yog txo qhov kev sib txhuam ntawm qhov sib txuas ntawm qhov muab tub lim thiab cov matrix, txo qhov kev nyiam rau theem kev sib cais, tab sis kuj tseem txhim kho cov khoom siv thiab cov huab cua tsis kam ntawm cov khoom sib xyaw los ntawm kev ua kom zoo ntawm txoj kev nyuaj siab.
Qhov sib txawv ntawm cov qauv tsim ua rau muaj kev sib txawv ntawm lawv cov txheej txheem: monoalkoxy hom cia siab rau hydrolysis sai-condensation cov tshuaj tiv thaiv ntawm pawg alkoxy, haum rau qis- kub, luv- cov ntawv thov txheej txheem; chelate hom kaw cov chaw ua haujlwm ntawm lub chaw titanium nrog cyclic ligands (xws li acetylacetone), txhim kho dej tsis kam thiab thermal stability; reactive functional pab pawg neeg ncaj qha koom nyob rau hauv lub polymer curing cov tshuaj tiv thaiv, tsim irreversible covalent bonds thiab pab txhawb interfacial durability.
Hauv cov ntsiab lus, txoj hauv kev ua haujlwm ntawm titanate coupling cov neeg ua haujlwm yog qhov tseem ceeb ntawm kev sib koom ua ke ntawm "kev sib txuas tshuaj lom neeg thiab kev thauj mus los - lub cev ntub dej thiab kev sib raug zoo - spatial stability thiab barrier". Los ntawm qhov tseeb molecular- theem tsim, nws tawg los ntawm qhov cuam tshuam ntawm inorganic-organic interface thiab muab kev txhawb nqa rau kev txhim kho kev ua tau zoo ntawm cov khoom sib xyaw.
