A photopolymer is a polymer that changes its properties when exposed to light, often in the ultraviolet frequency of the electromagnetic bonds that link one polymer chain to another. Can be formed by chemical reactions that are initiated by radiation. Change physical properties of photopolymers. | Photochemical reaction of Photopolymer Students: Thu Tran Loi Nguyen Tuyen Duong Truong Duong Teacher: Hoan Vu Tran Outline Introduction Trung hop quang .(photopolymerization) Photochemical reaction of photopolymer Free radial Cationic Photocrosslinking Photodegradation Ung dung Summary Reference Introduction A photopolymer is a polymer that changes its properties when exposed to light, often in the ultraviolet frequency of the electromagnetic spectrum. Introduction Photochemical reaction of photopolymer Free Radial Free radial Photoinitiator Direct Photoinitiator In-direct Photoinitiator Norrish I Norrish II Electron transfer Hydrogen abstraction Direct Photoinitiator Norrish I Direct Photoinitiator Norrish II In-direct Photoinitiator Electron transfer: In-direct Photoinitiator Hydrogen abstraction Cationic Onium: Cationic Aryl diazonium salts: Cationic Diaryl Iodonium Ex: Cationic Photocrosslinking Be bonds that link one polymer chain to another. Can be formed by chemical reactions that are initiated by radiation. Change physical properties of photopolymers. Photocrosslinking Crosslinking by dichromate Photodegradation Be degradation of a photodegradable molecule caused by the absorption of photons (light). Ex: photodegradation of diazonium salt Photodegradation Ex:Photodegradation of aryl azid group Ex: Photodegradation of o-Naphthoquinone diazide Problem hv Problem hv Summary Property Radical Cationic Reaction rate high Moderate/high Initiator by light Light and heat Volume change large negligible adhesion Moderate/good good Comparision between free radical and cationic polymerization Reference Polyme chuc nang va vat lieu lai cau truc nano book of Nguyen Duc Nghia. Photoinititor for free radical and cationic polymerization by . The potential of cationic photopolymerization’ long lived active center of Beth Ann Ficek in Univerity of Iowa. Thanks for your listening | Photochemical reaction of Photopolymer Students: Thu Tran Loi Nguyen Tuyen Duong Truong Duong Teacher: Hoan Vu Tran Outline Introduction Trung hop quang .(photopolymerization) Photochemical reaction of photopolymer Free radial Cationic Photocrosslinking Photodegradation Ung dung Summary Reference Introduction A photopolymer is a polymer that changes its properties when exposed to light, often in the ultraviolet frequency of the electromagnetic spectrum. Introduction Photochemical reaction of photopolymer Free Radial Free radial Photoinitiator Direct Photoinitiator In-direct Photoinitiator Norrish I Norrish II Electron transfer Hydrogen abstraction Direct Photoinitiator Norrish I Direct Photoinitiator Norrish II In-direct Photoinitiator Electron transfer: In-direct Photoinitiator Hydrogen abstraction Cationic Onium: Cationic Aryl diazonium salts: Cationic Diaryl Iodonium Ex: Cationic Photocrosslinking Be bonds that link one polymer chain to another. Can be formed by chemical reactions
