Umqalisi wokukhanya

Umqalisi wokukhanya

Kusistimu ekwazi ukuthwebula, okuhlanganisa iglue ye-UV, i-UV enamathelayo, uyinki ye-UV, njll., izinguquko zamakhemikhali zenzeka ngemva kokuthola noma ukumunca amandla angaphandle, futhi abole abe ama-radicals mahhala noma ama-cations, ngaleyo ndlela kucuphe ukusabela kwe-polymerization.

Ama-Photoinitiators yizinto ezingakhiqiza ama-radicals mahhala futhi ziqhubeke nokuqalisa i-polymerization ngokukhanyisa.Ngemva kokuba amanye ama-monomer akhanyisiwe, amunca ama-photon akhe isimo sokujabula M* : M+ HV →M*;

Ngemva kwe-homolysis ye-molecule ecushiwe, i-radical yamahhala engu-M*→R·+R '· iyakhiqizwa, bese i-polymerization ye-monomer iyaqaliswa ukuze yakhe i-polymer.

Ubuchwepheshe bokuphulukisa imisebe ubuchwepheshe obusha Bokonga Amandla Nokuvikela Imvelo, obukhanyiswa ukukhanya kwe-ultraviolet (UV), i-electron beam (EB), ukukhanya kwe-infrared, ukukhanya okubonakalayo, i-laser, i-chemical fluorescence, njll., futhi ihlangabezana ngokugcwele ne-“5E” izici: Isebenza kahle, Inika amandla, Ezomnotho, Yonga Amandla, futhi Ayihambisani Nemvelo. Ngakho-ke, yaziwa ngokuthi "Green Technology".

I-Photoinitiator ingenye yezingxenye ezibalulekile ze-adhesive photocurable, edlala indima ebalulekile ekwelapheni izinga.

Uma i-photoinitiator ikhanyiswa ukukhanya kwe-ultraviolet, imunca amandla okukhanya futhi ihlukaniseke ibe ama-radicals amahhala amabili asebenzayo, aqala uchungechunge lwe-polymerization ye-photosensitive resin kanye ne-diluent esebenzayo, okwenza okunamathelayo kuxhumeke futhi kuqiniswe. I-photoinitiator inezici zokusheshisa, ukuvikela imvelo nokonga amandla.

Ama-molecule aqalayo angakwazi ukumunca ukukhanya endaweni ye-ultraviolet (250~400 nm) noma isifunda esibonakalayo (400~800 nm). Ngemva kokumunca amandla okukhanya ngokuqondile noma ngokungaqondile, ama-athomu aqalayo ashintsha ukusuka endaweni ephansi ukuya kusimo se-singlet esijabulile, bese kuya kusimo se-triplet esijabulisayo ngoguquko lwe-intersystem.

Ngemuva kokuthi i-singlet noma i-triplet state ijabule ngokusabela kwamakhemikhali e-monomolecular noma i-bimolecular, izingcezu ezisebenzayo ezingaqala i-monomer polymerization zingaba ama-radicals mahhala, ama-cations, ama-anions, njll.

Ngokwendlela eyahlukene yokuqalisa, ama-photoinitiators angahlukaniswa abe i-free radical polymerization photoinitiator kanye ne-cationic photoinitiator, phakathi kwayo i-free radical polymerization photoinitiator isetshenziswa kakhulu kunazo zonke.