Abstract: A method of making a polymer network. The method includes providing a composition including a polythiol having more than one thiol group and a polyepoxide having more than one epoxide group, applying a solution including a photolatent base catalyst to a surface of the composition, and subsequently exposing the composition to light. Upon exposure to light, the photolatent base catalyst photochemically generates a first amine and at least partially cures at least the surface of the composition to form the polymer network.

Abstract: A composition includes a photolatent amine, camphorquinone, and a coumarin sensitizer. The coumarin sensitizer is triplet photosensitizer and has an absorbance with a wavelength of maximum absorbance in a range from 390 nanometers to 510 nanometers. Compositions that further include a polymerizable material are also disclosed. Polymer networks preparable from such compositions and methods for making the polymer networks are also disclosed.

Abstract: Polythioether polymers, sealants containing polythioether polymers, and compounds useful as stabilizing monomers in the manufacture of polythioether polymers are provided. In many embodiments the polymers and sealants demonstrate reduced risk of spoilage that may be caused by low temperature storage of the polymer or uncured sealant. Compounds useful as stabilizing monomers include compounds according to formula I: CH2?CR1—CHR2—S—R3—S—CHR4—CR5?CH2??[I] wherein R1, R2, R4 and R5 are independently selected from —H, —CH3 or —C2H5, and wherein R3 is selected from divalent groups comprising 2-12 carbon atoms, 0-5 ether oxygen atoms and 0-5 thioether sulfur atoms, which may be straight, branched or cyclic.

Abstract: The method includes applying a curable sealant to a surface of the aircraft component, forming a non-tacky skin on an exposed portion of the curable sealant within a first time period while allowing a portion of the curable sealant adjacent the surface of the aircraft component to be liquid for a second time period. The second time period is at least twice the first time period. The curable sealant comprises at least one of an adhesion promoter or a wetting agent.

Abstract: Provided are two-component curable compositions and methods thereof. The composition includes a base component comprised of a curable resin and a first compressible filler dispersed therein. The composition further includes a curative component comprised of a curing agent and a second compressible filler dispersed therein. The base and curative components react with each other upon mixing to provide a crosslinked network. When used with automated metering pumps, the compressibility of the base and curing agent components can be matched, allowing for a constant mix ratio despite variability in applied pressure.

Abstract: A dual curable thiol-ene composition comprising a polythiol, an unsaturated compound, a photoinitiator, an organic hydroperoxide (thermal initiator) and optionally a nitrogen-containing base, such as e.g. an N-heterocyclic compound (together with the organic hydroperoxide a redox initiator system). A cross-linked polymer prepared therefrom. A method of making such a polymer. A cured sealant comprising such a polymer. The sealant is preferably for use in aerospace.

Abstract: A lightning protective seal cap comprising a seal cap that defines an interior, and a quantity of an uncured sealant that is curable by the application of actinic radiation so as to bind the seal cap to a fastener. The interior of the seal cap contains the quantity of uncured sealant, the seal cap is positionable over the fastener such that at least a portion of the fastener resides in the interior of the seal cap, and when the seal cap is in position over the fastener, the sealant containing seal cap prevents electrical arcing to the fastener from a lightning strike.

Abstract: Polythioether polymers, sealants containing polythioether polymers, and compounds useful as stabilizing monomers in the manufacture of polythioether polymers are provided. In many embodiments the polymers and sealants demonstrate reduced risk of spoilage that may be caused by low temperature storage of the polymer or uncured sealant. Compounds useful as stabilizing monomers include compounds according to formula I: CH2?CR1—CHR2—S—R3—S—CHR4—CR5?CH2 [I] wherein R1, R2, R4 and R5 are independently selected from —H, —CH3 or —C2H5, and wherein R3 is selected from divalent groups comprising 2-12 carbon atoms, 0-5 ether oxygen atoms and 0-5 thioether sulfur atoms, which may be straight, branched or cyclic.

Abstract: The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and methods of their use, and in particular light weight seal caps having higher dielectric breakdown strength, lower weight, and/or lower wall thickness. In some embodiments, the seal caps according to the present invention are made of a material having a dielectric breakdown strength of greater than 1.0 kV/mm, in some embodiments greater than 15.0 kV/mm, and in some embodiments greater than 50.0 kV/mm. In some embodiments, the seal caps according to the present invention are thin-walled, having an average wall thickness of less than 1.5 mm and in some embodiments less than less than 0.5 mm. In some embodiments, the seal cap comprises a polyurethane polymer, a polythioether polymer, a polysulfide polymer, a fluorinated thermoplastic polymer, a THV polymer, a fluorinated thermoset polymer, an engineering thermoplastic, and/or a PEEK polymer.

Abstract: The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and in particular translucent or transparent seals or seal caps. In some embodiments, a seal cap which is optically translucent and optionally visibly transparent contains an uncured sealant, which is optionally optically translucent or visibly transparent, and is applied to a fastener. In some embodiments, the sealant is cured by application of actinic radiation to the sealant through the seal cap. In another aspect, a protected fastener construction is provided comprising: q) a fastener; r) a seal cap; and s) a cured sealant; wherein the sealant is optically translucent and optionally visibly transparent.

Abstract: The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and methods of their use, and in particular light weight seal caps having higher dielectric breakdown strength, lower weight, and/or lower wall thick-ness. In some embodiments, the seal caps according to the present invention are made of a material having a dielectric breakdown strength of greater than 1.0 kV/mm, in some embodiments greater than 15.0 kV/mm, and in some embodiments greater than 50.0 kV/mm. In some embodiments, the seal caps according to the present invention are thin-walled, having an average wall thickness of less than 1.5 mm and in some embodiments less than less than 0.5 mm In some embodiments, the seal cap comprises a polyurethane polymer, a polythioether polymer, a polysulfide polymer, a fluorinated thermoplastic polymer, a THV polymer, a fluorinated thermo-set polymer, an engineering thermoplastic, and/or a PEEK polymer.

Abstract: A curable composition having a polythiol; at least one unsaturated compound comprising two or more carbon-carbon double bonds, carbon-carbon triple bonds, or a combination thereof; and a dye compound represented by formula: A crosslinked composition prepared from the curable composition, a method for indicating curing in a curable composition, and a method of stabilizing a curable composition comprising a polythiol and at least one unsaturated compound comprising two or more carbon-carbon double bonds, carbon-carbon triple bonds, or a combination thereof are also disclosed.

Abstract: A polymerizable composition includes an organoborane-base complex that is a complex of an organoborane and a base, a decomplexing agent that at least partially liberates the organoborane from the organoborane-base complex, a polymerizable thiol-containing component comprising at least one polymerizable thiol-containing compound having a plurality of thiol groups in which the sulfur atom of the thiol group is covalently bonded to carbon, a hydroperoxide, and a polymerizable ethylenically-unsaturated component comprising at least one polymerizable ethylenically-unsaturated compound having a plurality of ethylenically-unsaturated groups. The combined amounts of the thiol-containing and ethylenically-unsaturated compounds total at least 50 percent by weight of all polymerizable material in the polymerizable composition. The composition may be provide as a two-part composition. Polymerized reaction product of the composition and methods of making the composition are also disclosed.

Abstract: A curable composition having a polythiol; at least one unsaturated compound comprising more than one carbon-carbon double bond, carbon-carbon triple bond, or a combination thereof; and a dye compound represented by formula (I). A crosslinked composition prepared from the curable composition, a method of making an at least partially crosslinked network, a method for indicating curing in a curable composition, and a method of stabilizing a curable composition comprising a polythiol and at least one unsaturated compound comprising more than one carbon-carbon double bond, carbon-carbon triple bond, or a combination thereof are also disclosed. Z is not reactive with the polythiol or unsaturated compound.

Abstract: A composition including a polythiol having more than one thiol groups, a polyepoxide having more than one epoxide group, a catalytic amount of a second amine, and a photolatent base catalyst. The photolatent base catalyst can photochemically generate a first amine, which may be the same as or different from the second amine. A polymer network preparable from the composition, and a method for making the polymer network are also disclosed.

Abstract: A method of making a polymer network. The method includes providing a composition including a polythiol having more than one thiol group and a polyepoxide having more than one epoxide group, applying a solution including a photolatent base catalyst to a surface of the composition, and subsequently exposing the composition to light. Upon exposure to light, the photolatent base catalyst photochemically generates a first amine and at least partially cures at least the surface of the composition to form the polymer network.

Abstract: Polythioether polymers, sealants containing polythioether polymers, and compounds useful as stabilizing monomers in the manufacture of polythioether polymers are provided. In many embodiments the polymers and sealants demonstrate reduced risk of spoilage that may be caused by low temperature storage of the polymer or uncured sealant. Compounds useful as stabilizing monomers include compounds according to formula I: CH2?CR1—CHR2—S—R3—S—CHR4—CR5?CH2 [I] wherein R1, R2, R4 and R5 are independently selected from —H, —CH3 or —C2H5, and wherein R3 is selected from divalent groups comprising 2-12 carbon atoms, 0-5 ether oxygen atoms and 0-5 thioether sulfur atoms, which may be straight, branched or cyclic.

Abstract: Compositions that are curable to polythioether polymers are provided, comprising: a) a dithiol monomer; b) a diene monomer; c) a radical cleaved photoinitiator; d) a peroxide; and e) an amine; where the peroxide and amine together are a peroxide-amine redox initiator. In some embodiments, the amine is a tertiary amine. In some embodiments, the amine is selected from the group consisting of dihydroxyethyl-p-toluidine, N,N-diisopropylethylamine, and N, N, N?, N?, N?-pentamethyl-diethylenetriamine. In some embodiments, the peroxide is selected from the group consisting of di-tert-butyl peroxide, methyl ethyl ketone peroxide, and benzoyl peroxide. In some embodiments, the composition may additionally comprise a polythiol monomer having three or more thiol groups.

Abstract: The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and in particular translucent or transparent seals or seal caps. In some embodiments, a seal cap which is optically translucent and optionally visibly transparent contains an uncured sealant, which is optionally optically translucent or visibly transparent, and is applied to a fastener. In some embodiments, the sealant is cured by application of actinic radiation to the sealant through the seal cap. In another aspect, a protected fastener construction is provided comprising: q) a fastener; r) a seal cap; and s) a cured sealant; wherein the sealant is optically translucent and optionally visibly transparent.

Abstract: The present disclosure provides methods and articles useful in sealing fasteners, including seal caps and in particular translucent or transparent seals or seal caps. In some embodiments, a seal cap which is optically translucent and optionally visibly transparent contains an uncured sealant, which is optionally optically translucent or visibly transparent, and is applied to a fastener. In some embodiments, the sealant is cured by application of actinic radiation to the sealant through the seal cap. In another aspect, a protected fastener construction is provided comprising: q) a fastener; r) a seal cap; and s) a cured sealant; wherein the sealant is optically translucent and optionally visibly transparent.