Tej zaum koj yuav tau pom hauv lub neej tias qee cov khoom TPU raug cuam tshuam los ntawm ultraviolet rays. Tom qab lub sijhawm siv, qee qhov yellowing tshwm sim ntau dua lossis tsawg dua. Dab tsi yog qhov ua rau yellowing?
Muaj ib ntu hu ua ntu nyuaj hauv qhov hnyav molecular ntawm TPU. Ob chav benzene nplhaib qauv ntawm MDI cov khoom nyob rau hauv nws yog unsaturated thiab yooj yim oxidized nyob rau hauv ultraviolet rays. Qhov no oxidation ua rau quinone hloov xim, uas yog qhov peb hu ua yellowing. Yog li peb tuaj yeem txhim kho nws li cas?
Feem ntau peb ntxiv ob yam: ib qho yog ultraviolet absorber, thiab lwm yam yog antioxidant. Kev sib xyaw ntawm ob yam khoom no thiab ntxiv rau lawv tuaj yeem txo qhov kev siv ntawm ultraviolet rays, txhim kho lub ultraviolet tsis kam ntawm TPU, thiab ua rau cov ntu nyuaj yuav tsis tshua muaj oxidized, yog li ncua kev yellowing ntawm TPU uas yuav tshwm sim tom qab siv mus ntev.