Mawu Oyamba

Antioxidants (kapena kutentha stabilizer) ndi zowonjezera zomwe zimagwiritsidwa ntchito kuletsa kapena kuchedwetsa kuwonongeka kwa ma polima chifukwa cha mpweya kapena ozoni mumlengalenga. Ndiwowonjezera omwe amagwiritsidwa ntchito kwambiri pazinthu za polima. Zopaka zimawonongeka chifukwa cha kutentha kwa oxidation pambuyo pophikidwa pa kutentha kwakukulu kapena padzuwa. Zochitika monga kukalamba ndi chikasu zidzakhudza kwambiri maonekedwe ndi machitidwe a mankhwala. Pofuna kupewa kapena kuchepetsa kuchitika kwa izi, ma antioxidants nthawi zambiri amawonjezeredwa.

Kuwonongeka kwa makutidwe ndi okosijeni a ma polima makamaka kumachitika chifukwa cha unyolo wamtundu wa free radical reaction womwe umayambitsidwa ndi ma free radicals opangidwa ndi ma hydroperoxides akatenthedwa. Kuwonongeka kwa ma oxidation a ma polima kumatha kuletsedwa ndi kugwidwa kwaufulu kwa ma radicals ndi kuwonongeka kwa hydroperoxide, monga momwe chithunzi chili pansipa. Mwa iwo, ma antioxidants amatha kuletsa okosijeni pamwambapa ndipo amagwiritsidwa ntchito kwambiri.

 

Mitundu ya antioxidants

Antioxidantsatha kugawidwa m'magulu atatu molingana ndi ntchito zawo (mwachitsanzo, kulowerera kwawo mu auto-oxidation chemical process):

unyolo kuthetsa antioxidants: iwo makamaka amatenga kapena kuchotsa ma free radicals opangidwa ndi polima auto-oxidation;

hydroperoxide kuwola antioxidants: amalimbikitsa makamaka kuwonongeka kosasinthika kwa hydroperoxides mu ma polima;

iron ion passivating antioxidants: amatha kupanga ma chelates okhazikika okhala ndi ayoni owopsa achitsulo, potero amalepheretsa ma ayoni achitsulo panjira yotulutsa ma polima.

Pakati pa mitundu itatu ya antioxidants, unyolo-kutha antioxidants amatchedwa primary antioxidants, makamaka ankalepheretsa phenols ndi sekondale onunkhira amines; mitundu ina iwiriyi imatchedwa oxiliary antioxidants, kuphatikizapo phosphites ndi mchere wachitsulo wa dithiocarbamate. Kuti mupeze zokutira zokhazikika zomwe zimakwaniritsa zofunikira pakugwiritsa ntchito, kuphatikiza kwa ma antioxidants angapo nthawi zambiri kumasankhidwa.

 

Kugwiritsa ntchito ma antioxidants mu zokutira

1. Ntchito mu alkyd, poliyesitala, unsaturated polyester
Muzinthu zomwe zili ndi mafuta a alkyd, pali zomangira ziwiri ku madigiri osiyanasiyana. Zomangira zing'onozing'ono, zomangira zapawiri, ndi zomangira zapawiri zophatikizana zimasinthidwa mosavuta kuti zipange ma peroxides pa kutentha kwakukulu, kupangitsa mtundu kukhala wakuda, pomwe ma antioxidants amatha kuwola ma hydroperoxides kuti achepetse mtundu.

2. Ntchito mu synthesis wa PU kuchiritsa wothandizira
PU kuchiza wothandizira nthawi zambiri amatanthauza prepolymer ya trimethylolpropane (TMP) ndi toluene diisocyanate (TDI). Pamene utomoni umakhala ndi kutentha ndi kuwala panthawi ya kaphatikizidwe, urethane imawonongeka kukhala ma amines ndi olefins ndikuphwanya unyolo. Ngati amine ndi wonunkhira, amapangidwa ndi okosijeni kukhala quinone chromophore.

3. Ntchito mu zokutira thermosetting ufa
Antioxidant yosakanikirana ya phosphite yapamwamba kwambiri ndi phenolic antioxidants, yoyenera kuteteza zokutira za ufa kuchokera ku kuwonongeka kwa okosijeni panthawi yokonza, kuchiritsa, kutenthedwa ndi njira zina. Mapulogalamuwa akuphatikiza polyester epoxy, TGIC yotsekeka ya isocyanate, TGIC m'malo, mizere ya epoxy compounds ndi thermosetting acrylic resins.

 

Nanjing Reborn New Materials amapereka mitundu yosiyanasiyana yaantioxidantsza pulasitiki, zokutira, mafakitale a labala.

Ndi zatsopano komanso kupita patsogolo kwa mafakitale okutira, kufunikira kwa ma antioxidants pazovala kudzakhala koonekeratu, ndipo danga lachitukuko lidzakhala lalikulu. M'tsogolomu, ma antioxidants adzakula molunjika ku mamolekyu apamwamba kwambiri, kuchita zinthu zambiri, kuchita bwino kwambiri, kwatsopano, kuphatikizika, kuyankha komanso kuteteza chilengedwe. Izi zimafuna akatswiri kuti azichita kafukufuku wozama kuchokera kumakina ndi kagwiritsidwe ntchito kuti apitilize kuwongolera, kuchita kafukufuku wozama pamapangidwe a ma antioxidants, ndikupanganso ma antioxidants atsopano komanso ogwira mtima potengera izi, zomwe zidzakhudza kwambiri kukonza ndi kugwiritsa ntchito kwa mafakitale zokutira. Ma Antioxidants a zokutira adzawonjezera kuthekera kwawo kwakukulu ndikubweretsa zabwino kwambiri zachuma ndiukadaulo.


Nthawi yotumiza: Apr-30-2025