Umqalisi wokukhanya

Umqalisi wokukhanya

Kwinkqubo yokufota, kubandakanywa iglue ye-UV, i-UV i-UV, i-inki ye-UV, njl., utshintsho lweekhemikhali lwenzeka emva kokufumana okanye ukufunxa amandla angaphandle, kwaye ibole ibe yi-radicals yamahhala okanye i-cations, ngaloo ndlela ibangela ukusabela kwe-polymerization.

I-Photoinitiators zizinto ezinokuvelisa i-radicals yamahhala kwaye ziqhube phambili ziqalise i-polymerization ngokukhanyisa.Emva kokuba ezinye iimonomer zikhanyisiwe, zifunxa iifotoni kwaye zenze isimo sochulumanco M* : M+ HV →M*;

Emva kwe-homolysis yemolekyuli esebenzayo, iradical yasimahla M*→R·+R '· iyenziwa, kwaye emva koko i-polymerization ye-monomer iyaqaliswa ukwenza ipholima.

Itekhnoloji yokunyanga i-radiation yitekhnoloji entsha yoLondolozo lwaMandla kunye nokuKhuselwa kokusiNgqongileyo, ekhanyiswa kukukhanya kwe-ultraviolet (UV), i-electron beam (EB), ukukhanya kwe-infrared, ukukhanya okubonakalayo, i-laser, i-chemical fluorescence, njl., kwaye idibana ngokupheleleyo ne-"5E" iimpawu: Ukusebenza kakuhle, ukwenza, uQoqosho, ukuGcinwa kwamandla, kunye noBungane beNdalo. Ke ngoko, yaziwa ngokuba yi "Green Technology".

I-Photoinitiator yenye yezinto ezibalulekileyo zokuncamathelisa okufotayo, ezidlala indima eqinisekileyo kwireyithi yokunyanga.

Xa i-photoinitiator ihlanjululwa kukukhanya kwe-ultraviolet, ithatha amandla okukhanya kwaye ihlukane ibe ngama-radicals amabini asebenzayo, aqala i-polymerization ye-chain ye-photosensitive resin kunye ne-diluent esebenzayo, eyenza i-adhesive cross-linked and solidified. I-photoinitiator ineempawu zokukhawuleza, ukukhuselwa kwendalo kunye nokugcinwa kwamandla.

Iamolekyu zomqalisi zinokuthatha ukukhanya kummandla we-ultraviolet (250 ~ 400 nm) okanye ummandla obonakalayo (400 ~ 800 nm). Emva kokufunxa amandla okukhanya ngokuthe ngqo okanye ngokungathanga ngqo, iimolekyuli zomqalisi zitshintsha ukusuka kumhlaba osezantsi ukuya kwindawo echulumancisayo ye-singlett, emva koko iye kwi-triplet state echulumancisayo ngotshintsho lwe-intersystem.

Emva kokuba i-singlett okanye i-triplet state ivuyiswe nge-monomolecular okanye i-bimolecular reaction reaction, amaqhekeza asebenzayo anokuqalisa i-polymerization ye-monomer ingaba yi-radicals yamahhala, i-cations, i-anions, njl.

Ngokweendlela ezahlukeneyo zokuqalisa, ii-photoinitiators zinokwahlulwa zibe yi-photoinitiator ye-radical radical yasimahla kunye ne-cationic photoinitiator, phakathi kwayo i-photoinitiator yasimahla ye-polymerization yeyona isetyenziswa kakhulu.