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Photoinitiation methacrylamide

This reaction is utilized by Burrows et al. [70] to photoinitiate grafting of acrylamide, acrylic acid, methacrylamide, and acrylonitrile on cellulose triacetate in acidic aqueous solution. [Pg.257]

The first reaction describes the excitation of uranyl ions. The excited sensitizer can lose the energy A by a non-radiative process (12b), by emission (12c) or by energy transfer in monomer excitation to the triplet state (12d). Radicals are formed by reaction (12e). The detailed mechanism of step (12e) is so far unknown. Electron transfer probably occurs, with radical cation and radical anion formation these can recombine by their oppositely charged ends. The products retain their radical character. Step (12g) corresponds to propagation and step (12f) to inactivation of the excited monomer by collision with another molecule. The photosensitized initiation and polymerization of methacrylamide [69] probably proceeds according to scheme (12). Ascorbic acid and /7-carotene act as sensitizers of isoprene photoinitiation in aqueous media [70], and diacetyl (2, 3-butenedione) as sensitizer of viny-lidene chloride photopolymerization in a homogeneous medium (N--methylpyrrolidone was used as solvent) [71]. [Pg.89]

In the photopolymerization of methacrylamide by benzoin methyl ether, chain-transfer to monomer has been found to be important, and benzalde-hyde is reported to be an inefficient photoinitiator of methyl methacrylate polymerization unless benzophenone and triethylamine are present. Acetophenone has been found to sensitize the cycloaddition of maleic anhydride to 7-oxabicyclo[2.2.1]heptan-5-one-2,3-dicarboxylic anhydride, , a-hydroxy-acetophenone derivatives have been found to be non-yellowing initiators, and h.p.l.c. has been used to determine residual carbonyl photoinitiators in u.v.-cured resins. In the emulsion-polymerization of methyl methacrylate using an aromatic ketone and a continuous or intermittent laser, the former conditions were found to be similar to those under continuous u.v. irradiation. The dependence of the polymerization rate and average chain-length on the absorbance of the initiator used in the photoinitiated polymerization of vinyl monomers has been studied. Interestingly, irrespective of all conditions, maximum conversion is observed when initiator absorbance is 2.51. "... [Pg.476]

A.H.Reine and J.C. Arthur,Jr., Photoinitiated polymerisation of Methacrylamide with cotton cellulose, Text.Res.Jo 42 155 (1972). [Pg.344]


See other pages where Photoinitiation methacrylamide is mentioned: [Pg.708]    [Pg.234]    [Pg.222]    [Pg.182]   
See also in sourсe #XX -- [ Pg.233 ]




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Methacrylamides

Photoinitiated

Photoinitiation

Photoinitiator

Photoinitiators

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