Effect of molecular oxygen on the UV-polymerization of methyl methacrylate initiated by 2,2-dimethoxy-2-phenylaceto-phenone and 1-hydroxycyclohexyl phenyl ketone in solution
The photopolymerization of methyl methacrylate (MMA) in a dilute benzene solution containing 2,2-dimethoxy-2-phenylacetophenone (DMPA) or 1-hydroxycyclohexyl phenyl ketone (HCPK) was investigated. Product analyses indicate that under a nitrogen atmosphere in the presence of MMA both radicals from HCPK are involved in polymerization of MMA whereas only 30% of the benzoyl radicals and 15% of the 1,1-dimethoxybenzyl radicals from DMPA are involved in radical polymerization. Under an oxygen atmosphere, products are formed in increased amounts, resulting in fewer radicals available for polymerization. The polymerization is inhibited by oxygen, as shown by a five-fold decrease in polymerization quantum efficiency, and lower yields of poly(methyl methacrylate). The addition of amines is not effective in relieving this effect.
- Research Organization:
- Armstrong World Industries, Inc., Lancaster, PA
- OSTI ID:
- 5849008
- Journal Information:
- J. Radiat. Curing; (United States), Journal Name: J. Radiat. Curing; (United States) Vol. 13:1; ISSN JRDCA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400500* -- Photochemistry
ACETOPHENONE
ADDITIVES
AMINES
AROMATICS
BENZENE
BENZOYL RADICALS
CARBOXYLIC ACID ESTERS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
ELEMENTS
ESTERS
HYDROCARBONS
INHIBITION
KETONES
KINETICS
METHACRYLIC ACID ESTERS
METHYL METHACRYLATE
NITROGEN
NONMETALS
ORGANIC COMPOUNDS
OXYGEN
PHOTOCHEMICAL REACTIONS
POLYMERIZATION
RADIATIONS
RADICALS
REACTION KINETICS
ULTRAVIOLET RADIATION
YIELDS