Light stabilizer (English din: Light stabilizer; photostabilizer) yɛ ade a wɔde ka ho ma polymer nneɛma (te sɛ plastic, rɔba, nneɛma a wɔde kata so, nhama a wɔde yɛ nneɛma). Etumi bɔ ne ho ban anaasɛ ɛtwetwe ahoɔden a ɛma ahoɔden a ɛwɔ nipadua no mu no, dum oxygen a ɛyɛ biako na ɛma hydrogen yɛ adwuma. Ebetumi asɛe nneɛma ayɛ no nneɛma a ɛnyɛ adwuma ne dwumadi afoforo, ma enti wɔ hann a ɛyɛ hyew no ase no, polymer no betumi ayi anaasɛ ayɛ brɛoo a ebetumi aba sɛ photochemical reactions, asiw anaasɛ atwe kwan a wɔfa so yi photoaging no ase, na ɛnam so anya atirimpɔw a ɛne sɛ wɔbɛtrɛw ɔsom nkwa a ɛwɔ polymer nneɛma mu no mu. Light stabilizer yɛ ade a wɔde ka ho a ebetumi abɔ nneɛma a ɛwɔ nkwa mu ho ban afi hann a ɛsɛe ho. Ebetumi agye, apete na ɛde mframa a ɛyɛ hu a ɛma mframa bɔne a ano yɛ den no akɔ, na ɛnam so asiw oxidation, onyin, asɛe ne nneɛma afoforo a enye ano yiye, na atrɛw nneɛma a wɔde yɛ adwuma no mu. Nneɛma a ɛma hann a ɛma hann no gyina no yɛ adwuma titiriw denam akwan atitiriw abien so: biako ne hann a ɛtwetwe nneɛma, kyerɛ sɛ, hann a ɛma hann no tumi twetwe mframa a ano yɛ den no na ɛdan ahoɔden a ɛma ahoɔden a ɛma hann no yɛ hyew, na ɛnam so ma mframa a ano yɛ den a ɛwɔ nneɛma a nkwa wom so no so tew; Ɔfoforo no ne free radical capture mechanism, kyerɛ sɛ, light stabilizers betumi ne free radicals abɔ mu, na ɛnam so atew free radical reactions no so na abɔ organic nneɛma ho ban afi oxidation ne onyin a free radicals de ba no ho. Sɛnea akwan horow a wɔfa so yɛ ade ne nhyehyɛe mu su ahorow kyerɛ no, wobetumi akyekyɛ hann a ɛma nneɛma gyina hɔ no mu ayɛ no ahorow pii. Wɔn mu no, nneɛma a ɛma hann no gyina hɔ a ɛtaa ba no bi ne: absorption light stabilizers, twetwe hann a ɛma ɛyɛ den ne chelating hann a ɛma ɛyɛ den.
1. Hann a wɔde bɔ nneɛma ho ban: Eyi yɛ ade bi a ebetumi asiw mframa a ano yɛ den ano anaasɛ ɛda adi, na ɛmma hann nkɔ polymer no mu, na ɛnam so bɔ polymer no ho ban. Nneɛma a ɛma hann a ɛyɛ hare no bi ne nneɛma a ɛnyɛ nkwaboaa te sɛ carbon black ne titanium oxide, ne nneɛma a ɛwɔ nipadua no mu te sɛ phthalocyanine blue ne phthalocyanine green. Wɔn mu no, carbon black wɔ shielding effect a eye sen biara.
2. Ultraviolet absorber: Ebetumi atwe ultraviolet rays a asorɔkye tenten yɛ 290 kosi 410nm yiye, bere a ɛntaa ntwe hann a wotumi hu no. Ɛwɔ ɔhyew a ɛyɛ den yiye ne hann a ɛyɛ den. Sɛnea wɔn nnuru nhyehyɛe kyerɛ no, wobetumi akyekyɛ mu titiriw: O-hydroxybenzophenones, benzotriazoles, salicylates, triazines, ne acrylonitriles a wɔde asi ananmu. Wɔde di dwuma sɛ kanea a ɛboa ma nneɛma gyina hɔ pintinn na ɛma hann no gyina, titiriw wɔ polyolefins anaa ade a wɔde kata so mu.
3. quencher: Ebetumi agye ahoɔden a chromophore no twetwe wɔ plastic no mu no atom na asɛe saa ahoɔden yi wɔ ɔhyew, fluorescence anaa phosphorescence mu, na ɛnam so abɔ polymer no ho ban afi ultraviolet a ɛsɛe no ho. Ɛwɔ tumi pa a ɛma ɛyɛ den wɔ polymers so na wɔde di dwuma kɛse wɔ sini ne nhama mu. Titiriw no, divalent organic nickel chelates bi. Organic nickel light stabilizers wɔ adwumayɛ pa, nanso esiane awuduru a ɛwɔ heavy metal ions mu nti, wobetumi de nneɛma afoforo a ɛnyɛ{4}}a awuduru wom anaasɛ ɛba fam-awudi a ɛma awuduru dum asi ananmu.
4. Free radical capture agent: Saa hann a ɛma ɛyɛ den yi betumi akyere free radicals a ɛyɛ adwuma a wɔyɛ wɔ polymers mu, na ɛnam so asiw photooxidation nhyehyɛe no ano na ama hann atumi agyina. Titiriw no, esiw amine hann a ɛma ɛyɛ den (HALS) kwan. Ɛyɛ nea ɛhyɛ bɔ sen biara a ɛyɛ foforo a ɛyɛ soronko-efficiency light stabilizer, a sɛ wɔkyekyem pɛpɛɛpɛ a, afe afe ahwehwɛde nkɔso yɛ 20% kosi 30% wɔ amanaman ntam.
5. Hydroperoxide decomposer: Ɛyɛ amine hann a ɛma ɛyɛ den a wɔasiw ano no mu biako. Polymers tumi yɛ hydroperoxides bere a wɔrekora so na wɔreyɛ ho adwuma no, na ɛma polymers no sɛe photooxidative. Hydroperoxide a ɛporɔw no betumi asɛe peroxides ma ayɛ nitrogen a ɛyɛ den-oxygen free radicals na akɔ so akyere free radicals. , ɛnam so siw polymer a ɛsɛe no ano.
Sɛ yɛbɛbɔ no mua a, sɛ ade a ɛho hia a wɔde ka ho no, hann a ɛma nneɛma gyina hɔ pintinn no betumi atrɛw nneɛma a wɔde yɛ nneɛma a nkwa wom no som mu na ama wɔn ahotoso ne sɛnea ɛyɛ den no atu mpɔn. Yɛn adwumakuw no bɛkɔ so de wɔn ho ahyɛ nhwehwɛmu ne dwumadie a ɛfa kanea a ɛma hann no ho na wɔde nneɛma ne nnwuma a ɛyɛ papa ama adetɔfoɔ a wɔwɔ wiase nyinaa.
