UV a ɛma ɛyɛ den ne UV Masterbatches .
Wobetumi de nnuru a ɛma hann no agyina ahyɛ plastic mu de abɔ wɔn ho ban afi sɛ ɛbɛsɛe bere a wɔde wɔn ho ahyɛ owia hann ne wim tebea mu no. Polyolefins yɛ mmerɛw sɛ UV hann, oxygen, nsu ne ɔhyew bɛtow ahyɛ so, a ebetumi ama polymer ayɛ mmerɛw, ne soro a ɛpaapae, kɔla a ɛsakra ne nea ɛyɛ no a entumi nyɛ adwuma yiye.
photodegradation nhyehyɛe no fa akwan horow abien a ɛsono emu biara ho. Nea edi kan ne photolysis, baabi a UV mframa no twetwe na ɛma free radicals ba esiane polymer molecular bonds a ɛbubu nti. Nea ɛto so abien ne autoxidation, a ɛfa free radicals a ɛba bere a wɔde oxygen yɛ adwuma no ho ma ɛyɛ peroxyl radicals. Afei free radical foforo yi tow hyɛ polymer akyi dompe no so, na ɛma free radical foforo ba. Bere a adeyɛ no kɔ so no, wɔyɛ free radicals pii na wɔyɛ polymer molecule ahorow pii oxidized. Auto-oxidation cycle no wɔakyerɛ wɔ mfonini a ɛwɔ aseɛ ha no mu.
Wɔakyekyɛ hann a ɛma polyolefins mu no mu abiɛsa titiriw.
UV absorbers: nhwɛso a ɛtaa ba ne benzophenones ne benzotriazoles. Eyinom yɛ-ɛho ka, a etu mpɔn a ɛma ɛyɛ adwuma a ɛyɛ adwuma denam UV hann a ɛtwetwe so. Wɔyɛ adwuma yiye ma-bere a wɔde da wɔn ho adi no.
Nickel quencher: ahoɔden a wɔde fa nneɛma mu a ɛyɛ adwuma denam "edum" tebea a anigye wom a carbonyl kuw a wɔhyehyɛ wɔ photooxidation mu ne hydroperoxides a ɛporɔw so. Wɔmfa saa nneɛma a ɛma nneɛma gyina hɔ pintinn yi nni dwuma kɛse efisɛ dade a emu yɛ duru wom, ɛma kɔla kɔ ade a etwa to no mu, na ɛnyɛ nea etu mpɔn te sɛ HAL ahorow a wɔaka ho asɛm wɔ nkyekyem a edi hɔ no mu no.
Akwan a esiw amine hann a ɛma ɛyɛ den (HALS): Nneɛma a ɛma hann a ɛyɛ adwuma yiye sen biara ma polyolefin ahorow. a ɛwɔ molecule mu duru ne nhyehyɛe ahorow pii mu ma ɛkame ayɛ sɛ ɛfata sɛnea wɔde di dwuma biara. Wobetumi nso de adi dwuma sɛ bere tenten-bere mu ɔhyew a ɛma ɛyɛ den (hats). Wɔyɛ adwuma denam "trapping" free radicals a ɛba bere a wɔreyɛ photooxidation no so. Esiane sɛ stabilizer ahorow abiɛsa no nyinaa nam akwan horow so na ɛyɛ adwuma nti, wɔtaa de di dwuma bom de yɛ adwuma a ɛne ne ho di nsɛ. Sɛ nhwɛso no, wɔtaa de HALS di dwuma wɔ benzotriazoles ho na ama kɔla a ɛsakra wɔ kɔla ahorow mu no ayɛ ketewaa bi. Atifi hɔ stabilizers no nyinaa bɛyɛ adwuma yiye wɔ base stabilization package a ɛfata a ɛwɔ primary ne secondary antioxidants ne residual catalyst neutralizer no anim.
Ɛho hia sɛ yɛhyɛ no nsow sɛ nneɛma a wɔyɛ ho nkyerɛkyerɛmu, beae a ɛwɔ ne nnuru a atwa yɛn ho ahyia a ɛda adi no yɛ nneɛma atitiriw a ɛma wohu sɛnea nneɛma a wɔde gyina hɔ ma nneɛma no yɛ den ma wɔde di dwuma pɔtee bi.
