Kev Taw Qhia

Cov tshuaj antioxidants (lossis cov tshuaj stabilizers kub) yog cov khoom siv ntxiv uas siv los tiv thaiv lossis ncua qhov kev puas tsuaj ntawm cov polymers vim yog oxygen lossis ozone hauv huab cua. Lawv yog cov khoom siv ntxiv uas siv dav tshaj plaws hauv cov ntaub ntawv polymer. Cov txheej txheem yuav dhau los ua qhov kev puas tsuaj ntawm thermal oxidation tom qab ci ntawm qhov kub siab lossis raug tshav ntuj. Cov xwm txheej xws li kev laus thiab daj yuav cuam tshuam loj heev rau qhov tsos thiab kev ua tau zoo ntawm cov khoom. Txhawm rau tiv thaiv lossis txo qhov tshwm sim ntawm qhov sib txawv no, cov tshuaj antioxidants feem ntau raug ntxiv.

Kev puas tsuaj ntawm cov polymers los ntawm kev ua kom sov yog los ntawm cov tshuaj tiv thaiv dawb uas pib los ntawm cov tshuaj dawb uas tsim los ntawm hydroperoxides thaum cua sov. Kev puas tsuaj ntawm cov polymers los ntawm kev ua kom sov tuaj yeem raug txwv los ntawm kev ntes cov tshuaj dawb thiab kev rhuav tshem cov tshuaj hydroperoxide, raws li pom hauv daim duab hauv qab no. Ntawm lawv, cov tshuaj antioxidants tuaj yeem tiv thaiv kev oxidation saum toj no thiab yog li ntawd siv dav.

Cov hom tshuaj antioxidants

Cov tshuaj antioxidantsmuaj peev xwm muab faib ua peb pawg raws li lawv txoj haujlwm (piv txwv li, lawv txoj kev cuam tshuam hauv cov txheej txheem tshuaj lom neeg auto-oxidation):

cov tshuaj antioxidants uas xaus rau ntawm cov saw hlau: lawv feem ntau ntes lossis tshem tawm cov free radicals uas tsim los ntawm polymer auto-oxidation;

hydroperoxide rhuav tshem cov tshuaj antioxidants: lawv feem ntau txhawb nqa qhov tsis yog-radical decomposition ntawm hydroperoxides hauv polymers;

cov hlau ion passivating antioxidants: lawv tuaj yeem tsim cov chelates ruaj khov nrog cov hlau ions teeb meem, yog li passivating cov nyhuv catalytic ntawm cov hlau ions ntawm cov txheej txheem auto-oxidation ntawm polymers.

Ntawm peb hom tshuaj antioxidants, cov tshuaj antioxidants uas tsis ua haujlwm hu ua primary antioxidants, feem ntau yog cov hindered phenols thiab secondary aromatic amines; ob hom ntxiv hu ua auxiliary antioxidants, suav nrog phosphites thiab dithiocarbamate metal salts. Yuav kom tau txais ib txheej txheej ruaj khov uas ua tau raws li qhov yuav tsum tau ua, feem ntau yuav xaiv ntau yam antioxidants ua ke.

Kev siv cov tshuaj antioxidants hauv cov coatings

1. Siv rau hauv alkyd, polyester, unsaturated polyester
Hauv cov khoom uas muaj roj ntawm alkyd, muaj ob txoj hlua khi rau ntau qib. Ib txoj hlua khi ob txoj hlua khi, ntau txoj hlua khi ob txoj hlua khi, thiab cov hlua khi ob txoj hlua khi sib txuas yooj yim oxidized los ua peroxides ntawm qhov kub siab, ua rau xim tsaus dua, thaum cov tshuaj antioxidants tuaj yeem rhuav tshem cov hydroperoxides kom ua rau xim sib dua.

2. Siv rau hauv kev tsim cov neeg sawv cev PU curing
Tus neeg sawv cev PU curing feem ntau yog hais txog prepolymer ntawm trimethylolpropane (TMP) thiab toluene diisocyanate (TDI). Thaum cov resin raug cua sov thiab lub teeb thaum lub sijhawm synthesis, urethane decomposes rau hauv amines thiab olefins thiab tawg cov saw hlau. Yog tias amine yog aromatic, nws yog oxidized los ua quinone chromophore.

3. Daim ntawv thov hauv cov txheej txheem thermosetting hmoov
Ib qho tshuaj antioxidant sib xyaw ua ke ntawm cov phosphite thiab phenolic antioxidants ua haujlwm tau zoo, tsim nyog rau kev tiv thaiv cov hmoov txheej los ntawm kev puas tsuaj oxidative thermal thaum lub sijhawm ua, kho, overheating thiab lwm yam txheej txheem. Daim ntawv thov suav nrog polyester epoxy, blocked isocyanate TGIC, TGIC substitutes, linear epoxy compounds thiab thermosetting acrylic resins.

Nanjing Reborn Cov Khoom Siv Tshiab muab ntau hom kev pabcuamcov tshuaj antioxidantsrau cov yas, txheej, roj hmab lag luam.

Nrog rau kev tsim kho tshiab thiab kev vam meej ntawm kev lag luam coatings, qhov tseem ceeb ntawm cov antioxidants rau coatings yuav pom tseeb dua, thiab qhov chaw rau kev txhim kho yuav dav dua. Yav tom ntej, cov antioxidants yuav tsim kho mus rau hauv kev coj ntawm cov molecular loj, ntau yam, ua haujlwm tau zoo, tshiab, sib xyaw, teb tau thiab kev tiv thaiv ib puag ncig ntsuab. Qhov no yuav tsum tau cov kws kho mob ua qhov kev tshawb fawb tob tob los ntawm ob qho tib si mechanism thiab daim ntawv thov kom txuas ntxiv txhim kho lawv, ua qhov kev tshawb fawb tob tob txog cov yam ntxwv ntawm cov antioxidants, thiab ntxiv tsim cov antioxidants tshiab thiab ua haujlwm tau zoo raws li qhov no, uas yuav muaj kev cuam tshuam loj heev rau kev ua thiab daim ntawv thov ntawm kev lag luam coatings. Cov antioxidants rau coatings yuav siv lawv lub peev xwm loj hlob thiab coj cov txiaj ntsig zoo rau kev lag luam thiab kev siv tshuab.