Supported photoinitiator
AssigneeMinnesota Mining and Manufacturing Company
InventorsStephen W. Bany, Leigh E. Wood
Life of this patent
Estimating the term…
Abstract
Supported initiators for the radiation-activated polymerization of cationically-polymerizable compounds, particularly epoxide group-containing compounds, are described. The supported initiators comprise a particulate carrier and a photocatalytic ionic salt. The supported initiators are especially useful for the polymerization of cationically-polymerizable compounds in which the ionic salt alone is not soluble.
Claims24
A supported initiator for the radiation activated polymerization of a cationically-polymerizable compound in the absence of a nonreactive solvent comprising a dispersible particulate carrier less than 50 micrometers in its largest dimension carrying and supporting a photocatalytic ionic salt of an onium or an organometallic complex cation with a halogen-containing complex anion of a metal or metalloid to form a composite initiator of said ionic salt and carrier, said initiator being insoluble in said cationically-polymerizable compound, and when 10 parts by weight of said initiator are stirred into 90 parts by weight of an epoxypolysiloxane no more than 1 part by weight of said initiator settles out in 30 minutes.
An actinic radiation-curable composition comprising a cationically-polymerizable compound and a radiation-activated supported initiator in the absence of a nonreactive solvent comprising one part of a dispersible particulate carrier less than 50 micrometers in its largest dimension having a surface area of from about 1 to 1000 square meters per gram and carrying and supporting 0.005 to 5 parts by weight of a photocatalytic ionic salt of an onium or organometallic complex cation with a halogen containing complex anion of a metal or metalloid to form a composite initiator of said ionic salt and carrier, said initiator being insoluble in said cationically-polymerizable compound, and when 10 parts by weight of said initiator are stirred into 90 parts by weight of an epoxypolysiloxane no more than 1 part by weight of said initiator settles out in 30 minutes.
An article comprising a substrate bearing on at least one surface thereof a cured coating of a composition comprising
- (a) an actinic radiation-curable composition comprising a cationically-polymerizable compound in the absence of a nonreactive solvent, and
- (b) a radiation-activated supported initiator comprising one part of a dispersible particulate carrier less than 50 micrometers in its largest dimension having a surface area of from about 1 to 1000 square meters per gram carrying and supporting 0.005 to 5 parts by weight of a photocatalytic ionic salt of an onium or organometallic complex cation with a halogen containing complex anion of a metal or metalloid to form a composite initiator of said ionic salt and carrier, said initiator being insoluble in said cationically-polymerizable compound, and when 10 parts by weight of said initiator are stirred into 90 parts by weight of an epoxypolysiloxane no more than 1 part by weight of said initiator settles out in 30 minutes.
A process comprising
- (a) providing at least one cationically-sensitive compound;
- (b) dispersing in said compound a supported initiator in the absence of a nonreactive solvent, said initiator comprising a dispersible particulate carrier less than 50 micrometers in its largest dimension and carrying and supporting a photocatalytic ionic salt of an onium or an organometallic complex anion of a metal or metalloid to form a composite initiator of said ionic salt and carrier, said initiator being insoluble in said cationically-polymerizable compound, and when 10 parts by weight of said initiator are stirred into 90 parts by weight of an epoxypolysiloxane no more than 1 part by weight of said initiator settles out in 30 minutes, and
- (c) allowing a source of actinic radiation to contact the resulting dispersion for a time sufficient to polymerize said compound.
Dependencies are inferred from the claim text.