Yog vim li cas rau Discoloration ntawm PVC ntug Banding

Ntau tus neeg ntseeg hais tias los daws qhov teeb meem ntawm cov xim tsis sib xws hauv PVC ntug banding ua, tsuav yog cov kab daj ntawm cov kab ntau lawm hauv kev ua haujlwm kub, cov xim sib txawv tuaj yeem txo. Tab sis qee tus neeg kuj ntseeg tias PVC, CPE, thiab cov khoom ruaj khov muaj kev cuam tshuam ntau dua rau kev daj. Cov khoom sib txawv ntawm PVC, CPE, stabilizers, thiab lwm yam khoom tseem ceeb thiab cov khoom siv raw yuav muaj xim sib txawv thaum ua. Nyob rau hauv cov ntaub ntawv no, txawm ntxiv ib tug npaum li cas ntawm whitening agent los yog anti-aging tus neeg saib xyuas ib leeg yuav tsis muaj ntau npaum li cas.
Lub ntsiab manifestation ntawm discoloration tshwm sim los ntawm tshav kub, oxygen, thiab lub teeb aging yog yellowing ntawm profiles. Qee cov tuam txhab ruaj khov tau thov tias kev siv lawv cov khoom tuaj yeem txo tus naj npawb ntawm cov khoom thiab cov nqi qis dua piv rau cov tuam txhab zoo sib xws thaum txhawb nqa lawv cov khoom. Txawm hais tias cov txiaj ntsig tseem tuaj yeem tsim cov PVC profile uas zoo li txaus siab, hauv kev rov ua dua ntawm cov khoom pov tseg thiab cov txheej txheem kub ceev, vim tsis muaj thermal stability efficiency, kev puas tsuaj rau PVC molecular qauv tsis tuaj yeem pom los ntawm qhov muag liab qab. Yog li, cov xwm txheej hauv qab no tshwm sim thaum tsim khoom:
(1) Thaum lub sij hawm ua cov PVC ntug banding, nws tau pom tias cov xim tsis sib xws (me ntsis sib txawv ntawm cov xim raug tso cai);
(2) Cov profile qhia pom tseeb yellowing tom qab cua sov deformation;
(3) Lub xeev tau zoo tom qab cua sov, tab sis qhov profile ua grey tom qab ua rau hauv qhov rooj thiab qhov rais rau lub sijhawm luv luv. Cov profile tsis tig daj thaum lub sijhawm tsim khoom ib txwm, tab sis tig daj hauv cov khoom tom qab qhov rais.
Nyob rau hauv cov txheej txheem ntau lawm ntawm profiles, thaum lub hauv paus tej yam kev mob xws li raw cov ntaub ntawv thiab pwm tseem tsis hloov, yog hais tias qhov kub ntawm lub plasticizing thiab homogenization seem yog nce los ntawm 5 degree, cov resulting profiles yuav tig daj, qhia tsis txaus thermal stability efficiency. Yog li ntawd, tus nqi ntawm cov cua sov stabilizer ntxiv yuav tsum tau nce ntxiv, tshwj xeeb tshaj yog thaum ntxiv cov tshuaj ntxuav hniav dawb xws li fluorescent whitening agents hauv cov mis. Yog vim li cas rau discoloration ntawm PVC profiles tsis pom tseeb vim tsis txaus cua sov stabilizer.