Cov khoom siv "kev tiv thaiv ze" ---UV531

 

Cov hluav taws xob ultraviolet (UV)—qhov "teeb ​​meem tua neeg" uas tsis pom no—ua rau cov khoom siv ntau yam puas tsuaj tas li. Ua ib lub "tsom iav tiv thaiv" tiv thaiv cov hluav taws xob UV, cov khoom nqus UV tau dhau los ua cov neeg saib xyuas kev lag luam niaj hnub no uas tseem ceeb heev. Yuav kom nkag siab txog lawv cov teebmeem zoo kawg nkaus, peb yuav tsum xub paub txog qhov tseeb ntawm "tus neeg tua neeg uas tsis pom no."

Hauv cov ces kaum zais ntawm lub hnub ci spectrum (100-400nm), ultraviolet radiation lurks peb lub zog tshwj xeeb txaus ntshai:

 

Kev faib tawm	Qhov ntau ntawm qhov ntev (nm)	Cov yam ntxwv
UV-A	320-400	Lub teeb ultraviolet ntev ntev muaj lub zog nkag mus tob thiab tuaj yeem nkag mus rau hauv huab thiab iav.
UV-B	280-320	Lub teeb ultraviolet nruab nrab yog ib feem nqus los ntawm txheej ozone thiab muaj lub zog nkag mus tsis muaj zog.
UV-C	100-280	Cov hluav taws xob luv luv ultraviolet raug nqus tag nrho los ntawm txheej ozone, thiab me ntsis ntawm nws tseem nyob rau ntawm lub ntiaj teb.

 

• Cov Tub Rog Tshwj Xeeb UV-C: Nqa cov teeb ci siab tshaj plaws uas ua rau tuag taus, hmoov zoo tias txheej ozone yog thawj kab tiv thaiv rau lub ntiaj teb, ua rau nws tsis tshua muaj rau lawv mus txog hauv av.
• UV-B Vanguard: Tshwj xeeb hauv kev tsom mus rau cov khoom siv nto, nws tuaj yeem ua rau muaj kev tawg ntawm cov saw hlau molecular, ua rau nws yog tus ua rau cov yas tawg thiab cov xim ploj.
• UV -A Tus Neeg Tiv Thaiv: Ib tug 'lurker' uas muaj lub zog nkag mus tob heev, muaj peev xwm nkag mus tob rau hauv cov khoom siv kom ua rau muaj kev puas tsuaj qeeb tab sis txuas ntxiv mus. Kev tsom mus rau cov yam ntxwv ntawm cov yeeb ncuab no hauv ntau qhov wavelengths, cov khoom nqus ultraviolet tau tsim cov tswv yim tiv thaiv zoo - los ntawm cov pab pawg tshwj xeeb hauv lawv cov qauv molecular, lawv hloov lub zog puas tsuaj ntawm cov duab ultraviolet mus rau hauv qhov kub tsis muaj teeb meem, muab cov khaub ncaws tiv thaiv qhov muag tshwj xeeb rau cov khoom siv xws li yas, txheej, thiab tshuaj pleev ib ce.

 

I. Kev faib tawm ntawmCov Khoom Siv Ultraviolet Absorbers

Hauv kev lag luam niaj hnub no thiab lub neej txhua hnub, cov teebmeem laus ntawm ultraviolet (UV) hluav taws xob rau cov ntaub ntawv tsis tuaj yeem tsis quav ntsej. Txhawm rau daws qhov teeb meem no, cov kws tshawb fawb tau tsim ntau yam UV absorbers, uas yog cov teeb stabilizers uas nqus cov ultraviolet rays los ntawm lub hnub ci thiab cov teeb fluorescent yam tsis hloov lawv cov khoom. Raws li lawv cov qauv tshuaj lom neeg, UV absorbers feem ntau yog muab faib ua benzotriazoles, triazines, thiab benzophenones (xws liUV531).

Thaum xaiv cov khoom nqus ultraviolet, yuav tsum tau them sai sai rau qhov coefficient nqus ntawm cov resins sib txawv rau lub teeb ultraviolet kom xaiv tau lub teeb ultraviolet kom tsim nyog los tsim kev tiv thaiv "zoo tshaj plaws" rau cov resin.

1. PVC: Tus coefficient nqus dej tsawg ntawm cov wavelengths luv luv (200-300 nm), tab sis nws nce ntxiv ntau nrog rau qhov nce ntawm wavelength, qhia tias PVC muaj kev nkag siab ntau dua rau lub teeb ultraviolet ntev.

2. PE: Tus coefficient nqus qis qhia tias PE muaj peev xwm tsis muaj zog los nqus lub teeb ultraviolet thiab tiv taus lub teeb ultraviolet zoo.

3. PS: Tus coefficient absorption yog nruab nrab, tshwj xeeb tshaj yog qhov absorption muaj zog hauv 300-400 nm ntau.

4. PC: Nws muaj cov coefficient nqus siab, tshwj xeeb tshaj yog nyob rau hauv qhov ntev-nthwv ultraviolet ntau yam (350-400 nm), qhov twg nws qhia txog lub peev xwm nqus tau zoo.

5. PET: Nws muaj cov coefficient nqus siab, tshwj xeeb tshaj yog nyob rau hauv 300-400 nm qhov twg kev nqus yog qhov tseem ceeb.

6. EPOXY: Nws muaj qhov nqus dej siab tshaj plaws, qhia tias EPOXY rhiab heev rau lub teeb ultraviolet thiab nws yooj yim laus.

 

II. Kev Taw Qhia rauUV531- Ib qho tshuaj nqus ultraviolet uas ua raws li benzophenone

Cov qauv qauv:

Cov txheej txheem teb: UV531 yog ib qho khoom siv nqus ultraviolet uas siv benzophenone. Lub txheej txheem nqus ntawm UV-531 (2-hydroxy-4-n-octyloxybenzophenone) feem ntau yog raws li cov lus teb ntawm cov tshuaj sib txuas tshwj xeeb hauv nws cov qauv molecular rau lub teeb ultraviolet.

Cov txheej txheem tshwj xeeb yog raws li nram no:

1. Kev sib txuas hydrogen hauv cov molecule thiab kev tsim cov chelate rings

Cov pawg carbonyl thiab hydroxyl hauv UV-531 molecule tuaj yeem tsim cov hydrogen bonds intramolecular, tsim ib lub nplhaib chelate. Cov qauv no muab nws ib qho kev faib tawm huab electron tshwj xeeb, muab lub hauv paus rau kev nqus lub teeb ultraviolet.

2. Kev nqus hluav taws xob ultraviolet

Thaum ib lub molecule raug rau lub teeb ultraviolet ntawm ib qho wavelength tshwj xeeb, nws nqus tau lub zog thiab nkag mus rau hauv lub xeev excited. Thaum lub sijhawm no, cov cua sov molecular vibrations nce ntxiv, ua rau tawg ntawm cov hydrogen bonds intramolecular thiab qhib cov chelate rings.

3. Kev Hloov Pauv Zog thiab Kev Tso Tawm

Cov txheej txheem qhib lub nplhaib hloov lub zog siab ntawm lub teeb ultraviolet mus rau hauv cua sov lossis lwm yam zog qis (xws li lub zog vibrational), yog li tiv thaiv cov polymer los ntawm kev nqus lub zog ultraviolet thiab ua rau photooxidation. Tom qab ntawd, lub molecule rov qab mus rau nws cov qauv pib thiab tuaj yeem nqus lub teeb ultraviolet ntau zaus.

4. Kev ruaj khov ntawm photostability thiab kev caij tsheb kauj vab

UV-531 nws tus kheej muaj kev ruaj khov ntawm photostory siab thiab tuaj yeem nqus thiab tso tawm lub zog ultraviolet mus tas li. Txawm li cas los xij, hauv kev siv tiag tiag, nws cov kev ua tau zoo yuav maj mam poob qis vim yog kev raug rau lub sijhawm ntev rau cov chaw ib puag ncig xws li peroxide free radicals. Yog li ntawd, nws feem ntau siv ua ke nrog lwm cov tshuaj stabilizers (xws li hindered amine light stabilizers) los txhim kho cov txiaj ntsig tiv thaiv.

 

III. Cov Txiaj Ntsig Tshwj Xeeb ntawm UV531 - Tus Saib Xyuas Kev Tiv Thaiv Kev Laus Zoo Tshaj Plaws

1. Kev nqus tau zoo heev ntawm UV-B band: UV531 yog tsim los nqus cov UV-B band (280-320 nm).

Qhov no yog qhov tseem ceeb ntawm UV band uas ua rau cov khoom siv laus thiab kub hnyiab. UV531 muaj kev nqus dej zoo dua hauv UV-B band, ua rau nws tsim nyog rau cov xwm txheej uas xav tau kev tiv thaiv zoo.

2. Lub teeb ci ntsa iab thiab thermal stability zoo heev

UV531 tswj tau cov qauv tshuaj ruaj khov txawm tias nyob rau hauv lub teeb thiab kub ntev, ua rau nws tiv taus kev lwj thiab ua kom muaj kev tiv thaiv ntev.

3. Kev sib raug zoo dav dav

UV531 ua pov thawj zoo sib xws nrog ntau yam khoom siv polymer (xws li polyethylene, polypropylene, thiab polyvinyl chloride), ua rau nws yooj yim rau kev ua thiab thov.

4. Kev tiv thaiv ib puag ncig thiab kev nyab xeeb

UV531 tau dhau los ntawm kev kuaj mob lom neeg thiab tsis muaj teeb meem rau tib neeg thiab ib puag ncig, ua tau raws li cov qauv ib puag ncig thoob ntiaj teb thiab muaj kev nyab xeeb rau kev siv hauv kev ntim khoom noj thiab tshuaj pleev ib ce. Qhov sib txawv, benzotriazoles thiab triazines yuav ua rau muaj qee qhov kev pheej hmoo ib puag ncig vim muaj halogens lossis lwm yam khoom phom sij. Piv txwv li, plaub yam phenolic benzotriazole (suav nrog UV-328, UV-327, UV-350, thiab UV-320) tau raug pom zoo rau REACH txwv los ntawm European Chemicals Agency (ECHA).

 

IV. Cov Cheeb Tsam Siv ntawm 531 - Kev Pab Cuam Dav Dav ntawm Ntau Yam Khoom Siv

UV-531, ua ib qho tshuaj tiv thaiv kev laus uas ua tau zoo thiab muaj txiaj ntsig zoo, muaj ntau yam kev siv. Cov hauv qab no yog cov chaw siv tseem ceeb ntawm UV-531:

1. Kev lag luam yas