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Azo Polymerization Initiators Comprehensive Catalog Azo Polymerization Initiators Comprehensive Catalog FUJIFILM Wako Pure Chemical Corporation 4-1 Nihonbashi Honcho 2-Chome, Japan Chuo-Ku, Tokyo 103-0023, Japan TEL+81-3-3244-0305 FUJIFILM Wako Chemicals U.S.A. Corporation 1600 Bellwood Road Richmond, USA VA 23237, U.S.A. TEL+1-804-271-7677 FUJIFILM Wako Chemicals Europe GmbH Fuggerstrasse 12 D-41468 Neuss GERMANY Germany TEL+49-2131-311-0 Wako Chemicals (Shanghai) Co., Ltd. C1-C2, 26F, Junyao International Plaza, China 789 Zhaojiabang Road, Shanghai 200032, China TEL+86-21-6407-0511 Specialty Chemicals Web Site http://www.wako-chem.co.jp/kaseihin_en/ 180401 K2 SI 01 Introduction/What is Radical Polymerization? What is Azo Polymerization Initiator? Radical Formation Mechanism 01 INDEX 01 Introduction/What is Radical Polymerization? P1 07 Detailed Explanations 1. Azo Nitrile P11-14 What are Azo Polymerization Initiator? What are Azo Polymerization Initiator? Radical Formation Mechanism P2 2. Azo Ester P15-16 An azo polymerization initiator is a compound having an azo group (R-N=N-R’), which decomposes with heat 3. Azo Amide P17-18 Characteristics of Azo Polymerization Initiators and Comparison with Peroxides P3 02 4. Azo Imidazoline P19-20 and/or light, and forms carbon radical. The formed carbon radical is excellent in reactivity, and progresses polym- Examples of radical reactions using Azo Polymerization Initiators P4 5. Azo Amidine P21-22 erization and halogenation reactions of different types of vinyl monomers. 03 Selection Guide P5-6 6. Macro Azo Initiator P23-26 04 Decomposition Products P7-8 08 Product List P27-28 Radical Formation Mechanism of Azo Polymerization Initiators (Thermal Decomposition) 05 Solubility at a Glance P9 09 List of Related Items P29-32 06 [Reference] Photocharacterization P10 10 List of Applicable Laws P33-34 H2C=CH Carbon radical – N 2 Y CH3 CH3 CH 3 CH3 Monomer – – – Introduction – R – C – N=N – C – R 2 R – C R – C C – CH2 – – H2 or – – We develop a large variety of products taking advantage of our original – hv X Y organic synthesis technology, production technology, and refining technology X X X (1) Formation (2) Initiation reaction/ Polymer accumulated in our long experience in the manufacturing of reagents. of radical Propagation reaction Azo polymerization initiators are used as reaction initiators in the synthesis of polymers. They are used mainly as radical polymerization initiators in a wide (3)Recombination (4) Disproportionation range of industries, such as acryl resins for paints, water absorbent resins, polymer coagulants, adhesives, and paper finishing agents. R R CH3 CH2 = – – – We have approximately 20 types of azo polymerization initiators of 3 3 H C – C – C – CH R – C – H + R – C Formation by side reaction – – – organic-solvent soluble type and water-soluble type. – X X X X P7 Decomposition product What is Radical Polymerization? Radical polymerization is initiated by the formation of free radicals. Free radicals are formed by thermac energy, light, or (1) Formation of radical: Azo polymerization initiators decompose with heat or light, and form nitrogen gas and radioactivity. Radical polymerization is mainly used for the polymerization of vinyl monomers. In addition to radical carbon radicals. polymerization, cationic polymerization and anionic polymerization are common polymerization methods. In the case of *The decomposition rate (in solution) follows first-order reaction rate kinetics and aries due to structure differences. radical polymerization, initiators are generally used. The typical initiators are azo polymerization initiators and peroxides. (2) Initiation reaction/Propagation reaction: Azo polymerization initiator addition-polymerizes with vinyl monomers and forms a polymer. Characteristics of Radical Polymerization Initiators *Since a section of the azo polymerization initiator is introduced at the end of polymer, the effect of end group is expected. The efficiency of common azo polymerization initiators is approximately 0.5-0.7, and the remaining results in (3) ■ Radical polymerization initiator shows an effect even in a small amount. recombination or (4) disproportionation ■ It is not polar-sensitive, and a large number of solvent is available, a wide range of monomers can be polymerized. (3) Recombination: The carbon radicals which did not engage in polymerization recombine. ■ Polymerization at a low to high temperature ranges is possible. (4) Disproportionation: The carbon radicals which did not engage in polymerization abstracts hydrogen of other ■ Reaction with simple facility and equipment is possible. carbon radicals. Active Species Typical Reaction Addition Amount Type of Solvent Reference! Radical Formation Mechanism of Peroxides Usable in many X X Small amount Radical solvents CO 2R CO 2R CO 2R CO 2R ¡ R – C – O – O – C – R 2 R – C – O = = ¡ = O O O R – C – O R + CO 2 + O = XH O O O O Cationic HO O r × O Where R is an alkyl. R-CO2· decomposes (decarboxylation) immediately, and R· starts polymerization. Base O O R – Si(OMe 3) + H2O R Si O Si R O O Where R is an aryl, r Anionic × R-CO2· is hard to decompose (decarboxylation), so decarboxylation and addition reaction Base OH OH 2 O to monomers are competitive reactions. Therefore, R· or R-CO are the radical active species. HS SH + S S 1 Azo Polymerization Initiators Azo Polymerization Initiators 2 01 Introduction/What is Radical Polymerization? What is Azo Polymerization Initiator? Radical Formation Mechanism 01 INDEX 01 Introduction/What is Radical Polymerization? P1 07 Detailed Explanations 1. Azo Nitrile P11-14 What are Azo Polymerization Initiator? What are Azo Polymerization Initiator? Radical Formation Mechanism P2 2. Azo Ester P15-16 An azo polymerization initiator is a compound having an azo group (R-N=N-R’), which decomposes with heat 3. Azo Amide P17-18 Characteristics of Azo Polymerization Initiators and Comparison with Peroxides P3 02 4. Azo Imidazoline P19-20 and/or light, and forms carbon radical. The formed carbon radical is excellent in reactivity, and progresses polym- Examples of radical reactions using Azo Polymerization Initiators P4 5. Azo Amidine P21-22 erization and halogenation reactions of different types of vinyl monomers. 03 Selection Guide P5-6 6. Macro Azo Initiator P23-26 04 Decomposition Products P7-8 08 Product List P27-28 Radical Formation Mechanism of Azo Polymerization Initiators (Thermal Decomposition) 05 Solubility at a Glance P9 09 List of Related Items P29-32 06 [Reference] Photocharacterization P10 10 List of Applicable Laws P33-34 H2C=CH Carbon radical – N 2 Y CH3 CH3 CH 3 CH3 Monomer – – – Introduction – R – C – N=N – C – R 2 R – C R – C C – CH2 – – H2 or – – We develop a large variety of products taking advantage of our original – hv X Y organic synthesis technology, production technology, and refining technology X X X (1) Formation (2) Initiation reaction/ Polymer accumulated in our long experience in the manufacturing of reagents. of radical Propagation reaction Azo polymerization initiators are used as reaction initiators in the synthesis of polymers. They are used mainly as radical polymerization initiators in a wide (3)Recombination (4) Disproportionation range of industries, such as acryl resins for paints, water absorbent resins, polymer coagulants, adhesives, and paper finishing agents. R R CH3 CH2 = – – – We have approximately 20 types of azo polymerization initiators of 3 3 H C – C – C – CH R – C – H + R – C Formation by side reaction – – – organic-solvent soluble type and water-soluble type. – X X X X P7 Decomposition product What is Radical Polymerization? Radical polymerization is initiated by the formation of free radicals. Free radicals are formed by thermac energy, light, or (1) Formation of radical: Azo polymerization initiators decompose with heat or light, and form nitrogen gas and radioactivity. Radical polymerization is mainly used for the polymerization of vinyl monomers. In addition to radical carbon radicals. polymerization, cationic polymerization and anionic polymerization are common polymerization methods. In the case of *The decomposition rate (in solution) follows first-order reaction rate kinetics and aries due to structure differences. radical polymerization, initiators are generally used. The typical initiators are azo polymerization initiators and peroxides. (2) Initiation reaction/Propagation reaction: Azo polymerization initiator addition-polymerizes with vinyl monomers and forms a polymer. Characteristics of Radical Polymerization Initiators *Since a section of the azo polymerization initiator is introduced at the end of polymer, the effect of end group is expected. The efficiency of common azo polymerization initiators is approximately 0.5-0.7, and the remaining results in (3) ■ Radical polymerization initiator shows an effect even in a small amount. recombination or (4) disproportionation ■ It is not polar-sensitive, and a large number of solvent is available, a wide range of monomers can be polymerized. (3) Recombination: The carbon radicals which did not engage in polymerization recombine. ■ Polymerization at a low to high temperature ranges is possible. (4) Disproportionation: The carbon radicals which did not engage in polymerization abstracts hydrogen of other ■ Reaction with simple facility and equipment is possible. carbon radicals. Active Species Typical Reaction Addition Amount Type of Solvent Reference! Radical Formation Mechanism of Peroxides Usable in many X X Small amount Radical solvents CO 2R CO 2R CO 2R CO 2R ¡ R – C – O – O – C – R 2 R – C – O = = ¡ = O
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