Chaka cha 2024 chidzakhala nthawi yofunika kwambiri pamakampani opanga ma photovoltaic (PV) pamene mpikisano waukulu ukupititsa patsogolo ukadaulo wa ma cell ndi ntchito zamafakitale, zomwe zikupitilira liwiro la zaka khumi zapitazo. Ngakhale kuti zinthu zatsopanozi zapangidwa, kusankha filimu yolumikizira - kaya POE (polyolefin elastomer), EVA (ethylene-vinyl acetate copolymer), kapena EPE - ikadali nkhani yofunika kwambiri komanso yotsutsana kwambiri pa magalasi agalasi, mapepala osungira magalasi, ndi ma module osinthasintha.
Ma module a PV akunja amawonongeka chifukwa cha zinthu zinayi zazikulu zachilengedwe: kutentha, mpweya, madzi, ndi kuwala kwa ultraviolet (UV). Ngakhale kuti ntchito zamoyo sizingagwire ntchito bwino pa ntchitozi, zinthu zina zimakhala ndi gawo lalikulu pakusankha zinthu. Nkhaniyi ikuyerekeza momwe EVA ndi POE zimagwirira ntchito pansi pa mikhalidwe iyi, ndikupereka chidziwitso chatsopano ndi njira zosankhira zinthu.
1. Kutentha
EVA ndi POE zonse, zikalumikizidwa pamodzi, zimatha kupirira kutentha kwa nthawi yochepa pafupifupi 150°C. Komabe, EVA imawola kutentha kopitilira 200°C, kutulutsa asidi wambiri, pomwe POE imakhalabe yokhazikika mpaka kutentha kupitirira 300°C.
2. Mpweya
Pa kutentha kwa chipinda, zinthu zonse ziwirizi zimakhala ndi kukana bwino okosijeni. Komabe, EVA ili ndi ma monomers a free acetic acid, omwe amatha kuwosijeni pa kutentha kwakukulu. Mosiyana ndi zimenezi, POE, yopangidwa ndi ma bond a carbon-hydrogen okhazikika m'mankhwala, imafuna kutentha kwakukulu kuti igwirizane ndi mpweya.
3. Madzi
Magulu a ester a EVA amatha kugwidwa ndi hydrolysis, zomwe zimapangitsa kuti magulu a carboxyl apangidwe zomwe zimathandizira hydrolysis yowonjezera komanso kuwonongeka kwa zinthu. POE, yokhala ndi unyolo wake wa carbon-hydrogen, imakhala yokhazikika pamankhwala ndipo siyikhudzidwa ndi hydrolysis. Kuphatikiza apo, POE imawonetsa kukana kwabwino kwa nthunzi yamadzi, yokhala ndi chiwongola dzanja chotumizira nthunzi yamadzi (WVTR) cha pafupifupi 3 g/m2·24h pa 38°C ndi chinyezi cha 90%, poyerekeza ndi WVTR ya EVA ya 25 g/m2·24h. Kuchepa kwa kulowereraku kumawonjezera kuthekera kwa POE kuteteza zigawo zamkati za module ku kuwonongeka kwa chinyezi.
4. Kuwala kwa Ultraviolet
Kapangidwe ka unyolo wa POE wokhala ndi mpweya wochuluka wa kaboni-hydrogen kali ndi ma bond amphamvu a mankhwala—ma bond a CH pa 414 kJ/mol ndi ma bond a CC pa 332 kJ/mol—zomwe zimapangitsa kuti asagwere ku cleavage yomwe imabwera chifukwa cha UV. Mosiyana ndi zimenezi, magulu a ester a EVA ali ndi ma bond a CO okhala ndi mphamvu zomangira pansi pa 330 kJ/mol, zomwe zimakhala zosavuta kuwonongeka ndi UV.
Mapeto
Pakati pa zinthu zinayi zofunika kwambiri zomwe zimakhudza kudalirika kwa ntchito yakunja—kutentha, mpweya, madzi, ndi UV—POE nthawi zonse imagwira ntchito bwino kuposa EVA. Pamene maselo a PV akuyamba kugwira ntchito bwino kwambiri ndipo amafuna kudalirika kokhwima, POE ikadali chisankho chabwino kwambiri chotsimikizira kutulutsa mphamvu kwa nthawi yayitali komanso kokhazikika m'malo akunja.
