Bromine yog cov kua dej sib sib zog nqus xim av, cov khoom tsis yog xim hlau ntawm chav tsev kub, cov khoom siv tshuaj tseem ceeb, thiab tuaj yeem siv rau hauv cov nplaim hluav taws. Hauv qab no, cov chaw tsim khoom bromine yuav qhia txog lub luag haujlwm ntawm bromine hauv bromine raws li nplaim hluav taws.
Ua ntej, cia peb tham txog lub luag haujlwm ntawm cov nplaim hluav taws. Niaj hnub no, ntau yam khoom yog ua los ntawm cov khoom siv polymer, uas yog cov nplaim taws. Yog li ntawd, cov nplaim hluav taws uas tiv thaiv combustion yuav tsum tau ntxiv rau hauv kev tsim khoom. Cov nplaim hluav taws kub hnyiab tau muab faib ua ob pawg raws li lawv cov kev siv: reactive thiab additive.
Reactive nplaim retardants koom ua ib feem nyob rau hauv lub synthesis ntawm polymer cov ntaub ntawv thiab yog tsuas yog siv nyob rau hauv thermosetting plastics; Cov nplaim hluav taws xob ntxiv yog ntxiv thaum ua thiab molding, thiab tsuas yog tov nrog polymers. Feem ntau, lawv yog siv rau cov yas thermoplastic. Tam sim no, cov yas ntau yam uas siv cov nplaim hluav taws ntau yog polyurethane ua npuas ncauj, PVC, polystyrene, polyester thiab polyolefin. Bromine hauv halogens tuaj yeem siv los ua cov khoom siv raw rau cov nplaim hluav taws kub hnyiab los tsim ob qho tib si ntxiv thiab cov nplaim hluav taws kub.
Brominated hydrocarbon nplaim taws retardants muaj zog tiv thaiv tshav kub tshaj li chlorinated hydrocarbon nplaim retardants thiab tsis tshua muaj thermal decomposition thaum lub sij hawm resin ua. Lawv yog G-effect nplaim retardants thiab feem ntau ntxiv rau me me, nrog me ntsis cuam tshuam rau kev ua thiab kev siv cov khoom ntawm polymers. Lawv tuaj yeem siv rau polystyrene, ABS resin, polyurethane resin, epoxy resin, polyolefin, thiab qee yam polyurethane resins. Tshwj xeeb tshaj yog nyob rau hauv xyoo tas los no, nrog rau kev loj hlob ntawm kev lag luam thiab kev txhim kho ntawm tib neeg txoj kev ua neej nyob, qhov kev thov rau G-qib yas resin khoom tau nce ntau, thiab cov nyiaj ntawm G-effect nplaim retardants kuj nce. Kev tshawb fawb thiab kev loj hlob ntawm G-effect bromine nplaim retardants yog maj mam ua.
Yog li dab tsi yog cov nplaim retardant mechanism ntawm kev siv bromine raw cov ntaub ntawv los tsim nplaim retardants?
Qhov sib ntxiv ntawm cov nplaim hluav taws tuaj yeem tswj tau qhov tawg ntawm combustion kub zog; Muaj peev xwm cais cov nplaim hluav taws xob los ntawm huab cua; Nws muaj peev xwm dilute cov combustible gases tsim los ntawm yas decomposition los yog txiav tawm lub HO · dawb radical saw cov tshuaj tiv thaiv thaum combustion.
HO · radicals muaj lub zog siab thiab ceev cov tshuaj tiv thaiv ceev, yog li cov qib ntawm combustion yog txiav txim los ntawm kev loj hlob ntawm HO · radicals. Thaum muaj cov nplaim hluav taws kub hnyiab, hydrogen halides (HX) yuav decompose ntawm qhov kub thiab txias, thiab hydrogen halides tuaj yeem ntes thiab hloov siab zog H0 · radicals generated thaum lub sij hawm combustion rau low-zog halogen radicals x · thiab H20. Nyob rau tib lub sijhawm, halogen radicals x · hnov mob nrog hydrocarbons los tsim HX, thiab lub voj voog no yuav txiav tawm cov saw hlau ntawm cov dawb radicals.
Lub zog ua kom lub zog ntawm hydrogen bromide cov tshuaj tiv thaiv yog qhov tsawg, yog li me me ntawm lub nkoj r tuaj yeem sib tw nrog roj rau cov hluav taws xob dawb radicals los tsim kom muaj lub zog ua kom tsis muaj zog Br ·, uas ua lub luag haujlwm hauv kev tua hluav taws. Tsis tas li ntawd, cov atoms bromine generated tuaj yeem cuam tshuam nrog hydroxyl pawg kom rov tsim HBr, ua lub luag haujlwm hauv kev tua hluav taws.
Qhov sib ntxiv ntawm bromide txo qhov concentration ntawm H · thiab HO ·, ua tiav lub hom phiaj ntawm cov nplaim hluav taws.
