Abstract: Described is a polymerizable composition comprising (meth)acrylate ester monomer, a macromer and a polymerizable Norrish type I, photoinitiator. The resulting copolymers are physically crosslinked and generally those copolymers having greater than 20 percent macromer produce optically clear films and those having less than 20% macromer can provide high performance pressure sensitive adhesives.

Abstract: Controlled radical initiators, reaction mixtures containing the controlled radical initiators and various ethylenically unsaturated monomers, polymeric materials formed from the reaction mixtures, crosslinkable compositions containing the polymeric materials, and crosslinked compositions formed from the crosslinkable compositions are provided. The controlled radical initiators are bis-dithiocarbamate or bis-dithiocarbonate compounds having a single carbon between the two dithiocarbamate or dithiocarbonate groups.

Abstract: Crosslinkable compositions are provided that contain a) a polymeric material having at least two terminal dithiocarbamate groups or two terminal dithiocarbonate groups and b) a monomer composition that includes at least a crosslinking monomer having two or more ethylenically unsaturated groups. The polymeric materials in the crosslinkable compositions undergo chain extension and crosslinking reactions when exposed to actinic radiation in the ultraviolet region of the electromagnetic spectrum. Additionally, crosslinked compositions, articles that contain the crosslinkable compositions or the crosslinked compositions, and methods of making the articles are provided.

Abstract: Crosslinkable compositions are provided that contain a) a polymeric material having at least two terminal dithiocarbamate groups or two terminal dithiocarbonate groups and b) a monomer composition that includes at least a crosslinking monomer having two or more ethylenically unsaturated groups. The polymeric materials in the crosslinkable compositions undergo chain extension and crosslinking reactions when exposed to actinic radiation in the ultraviolet region of the electromagnetic spectrum. Additionally, crosslinked compositions, articles that contain the crosslinkable compositions or the crosslinked compositions, and methods of making the articles are provided.

Abstract: Described is a polymerizable polymer composition compri a) a copolymerizable macromer, b) a (meth)acrylate ester monomer; and c) a polyfunctional type I photoinitiator.

Abstract: Novel stress-reducing crosslinking oligomers that have application in dental restoratives, thin films, hardcoats, composites, adhesives, and other uses subject to stress reduction are described. The addition-fragmentation process of crosslinking results in a chain-transfer event that provides novel polymers that may be further functionalized. In addition, the addition-fragmentation oligomer comprises pendent functional groups that bond to a substrate by forming an ionic or covalent bond, or etch the substrate by chemically removing some material from the substrate.

Abstract: Controlled radical initiators, reaction mixtures containing the controlled radical initiators and various ethylenically unsaturated monomers, polymeric materials formed from the reaction mixtures, crosslinkable compositions containing the polymeric materials, and crosslinked compositions formed from the crosslinkable compositions are provided. The controlled radical initiators are bis-dithiocarbamate or bis-dithiocarbonate compounds having a single carbon between the two dithiocarbamate or dithiocarbonate groups.

Abstract: Novel stress-reducing crosslinking oligomers that have application in dental restoratives, thin films, hardcoats, composites, adhesives, and other uses subject to stress reduction are described. The addition-fragmentation process of crosslinking results in a chain-transfer event that provides novel polymers that may be further functionalized. In addition, the addition-fragmentation oligomer comprises pendent functional groups that bond to a substrate by forming an ionic or covalent bond, or etch the substrate by chemically removing some material from the substrate.

Abstract: Controlled radical initiators, reaction mixtures containing the controlled radical initiators and various ethylenically unsaturated monomers, and polymeric materials formed from the reaction mixtures are provided. The controlled radical initiators are bis-dithiocarbamate or bis-dithiocarbonate compounds with a single carbon atom between the two dithiocarbamate or dithiocarbonate groups. Polymeric materials such as homopolymers, random copolymers, and block copolymers can be prepared using the controlled radical initiators.

Abstract: A pressure sensitive adhesive composition is described comprising at least one low Tg (meth)acrylic polymer, and at least one silsesquioxane polymer crosslinker comprising a plurality of ethylenically unsaturated groups. The low Tg (meth)acrylic polymer typically has a Tg no greater than 10° C. In some embodiments, the low Tg (meth)acrylic polymer comprises at least 50, 55, 60, 65, or 70 wt-% of polymerized units derived from low Tg ethylenically unsaturated monomer(s). The low Tg ethylenically unsaturated monomer(s) is typically an alkyl (meth)acrylate comprising 4 to 20 carbon atoms. Also described are pressure sensitive adhesive articles and methods of preparing such articles.

Abstract: Addition-fragmentation agents of the formula are disclosed: wherein R1, R2 and R3 are each independently Z-Q-, a (hetero)alkyl group or a (hetero)aryl group with the proviso that at least one of R1, R2 and R3 is Zm-Q-, Q is a linking group have a valence of m+1; Z is an ethylenically unsaturated polymerizable group, m is 1 to 6; each X1 is independently —O— or —NR4—, where R4 is H or C1-C4 alkyl, and n is 0 or 1.

Abstract: Pressure sensitive adhesive compositions are described comprising at least one low Tg ethylenically unsaturated monomer, and at least one silsesquioxane polymer crosslinker comprising a plurality of ethylenically unsaturated groups. The low Tg ethylenically unsaturated monomer typically has a Tg no greater than 10° C. In some embodiments, the composition comprises at least 50, 55, 60, 65, or 70 wt-% of low Tg ethylenically unsaturated monomer. The low Tg ethylenically unsaturated monomer is typically an alkyl (meth)acrylate comprising 4 to 20 carbon atoms. In another embodiment, an adhesive composition is described comprising a syrup. The syrup comprising i) a free-radically polymerizable solvent monomer; ii) a solute (meth)acrylic polymer comprising polymerized units derived from one or more alkyl (meth)acrylate monomers, and iii) at least one silsesquioxane polymer crosslinker comprising a plurality of ethylenically unsaturated groups.

Abstract: A composition is described comprising a polymer. The polymer comprises polymerized units derived from a cleavable crosslinking monomer. The cleavable crosslinking monomer comprises at least two free-radically polymerizable groups and at least one group having the formula —O—C(R2)(R3)—O—, wherein R2 and R3 are independently hydrogen, alkyl, or aryl. The composition has a Tg no greater than 50° C. In some embodiments, the composition has a storage modulus greater than 3×105 Pa at 25° C. and 1 Hz and may be characterized as a non-tacky polymer. In other embodiments, the composition is a pressure sensitive adhesive. Upon cleavage of at least a portion of the polymerized monomeric units derived from the cleavable crosslinking monomer, the composition exhibits a change in at least one physical property. In another embodiment, the composition comprises a polymer and fragments. The fragments comprise the reaction product of a free-radically polymerizable group bonded to a polymer chain and a pendent hydroxyl group.

Abstract: Controlled radical initiators, reaction mixtures containing the controlled radical initiators and various ethylenically unsaturated monomers, and polymeric materials formed from the reaction mixtures are provided. The controlled radical initiators are bis-dithiocarbamate or bis-dithiocarbonate compounds with a single carbon atom between the two dithiocarbamate or dithiocarbonate groups. Polymeric materials such as homopolymers, random copolymers, and block copolymers can be prepared using the controlled radical initiators.

Abstract: An adhesive copolymer comprising acrylate ester monomer units, poly(phenyleneoxide)-functional (meth)acryloyl monomer units, optional acid-functional monomer units, and optional non-acid functional polar monomer units is described.

Abstract: Presently described are methods of preparing a pressure sensitive adhesive composition comprising providing a non-aqueous pressure sensitive adhesive comprising a (meth)acrylic copolymer comprising epoxy-functional groups; adding a chlorinated triazine crosslinker to the pressure sensitive adhesive; and coating the pressure sensitive adhesive onto a substrate. In some embodiments, the method may further comprise contacting the pressure sensitive adhesive to a second substrate. The method further comprises exposing the pressure sensitive adhesive to actinic radiation to crosslink the epoxy-functional groups by means of the triazine crosslinker. The step of exposing can occur at the time of manufacture (e.g. of a pressure sensitive adhesive coated articles such as a tape) or at the time of use. Also described are non-aqueous pressure sensitive adhesive compositions and adhesive-coated articles.

Abstract: Acrylic syrup polymer composition are provided by partially polymerizing a (meth)acrylic monomer mixture in the presence of a thiol chain transfer agent to produce a first syrup polymer composition comprising a low molecular weight solute (meth)acrylic copolymer and solvent monomers, quenching the chain transfer agent, further polymerizing the first syrup polymer composition to produce a second syrup polymer composition comprising the low molecular weight solute acrylic copolymer, a high molecular weight solute acrylic copolymer and optionally unreacted solvent monomers, optionally adding a crosslinker and photoinitiator; and further photopolymerizing the syrup polymer composition to produce a pressure-sensitive adhesive.

Abstract: A curable silsesquioxane polymer, a composition including such polymer, an article having a layer disposed thereon that includes the curable polymer and/or the cured polymer, and a method of forming a cured coating, wherein the curable silsesquioxane polymer includes a three-dimensional branched network having the formula: wherein the oxygen atom at the * is bonded to another Si atom within the three-dimensional branched network; R is an organic group comprising an ethylenically unsaturated group; and R2 is an organic group that is not an ethylenically unsaturated group; R3 is a non-hydrolyzable group; and n or n+m is an integer of greater than 3.

Abstract: A pattern article comprising a copolymer having polymerized units derived from a cleavable crosslinking monomer, to which a pattern is imparted by the release of incipient acid from a thermal acid generator or photoacid generator. The selective release of the acid provides a pattern of high crosslink density and low crosslink density as result of the incipient acid cleaving a portion of the crosslinks.

Abstract: An adhesive composition is described comprising a tertiary amine- and hydroxyl-functional (meth)acrylate copolymer and a styrene/maleic anhydride crosslinking agent, which when crosslinked, provides a pressure-sensitive adhesive and pressure-sensitive adhesive articles.