Crosslinked polyacrylate and method for producing same

Abstract

Disclosed are cross-linked polyacrylates and methods of making cross-linked polyacrylates, the compositions comprising at least two polyacrylates comprising one or more monofunctional acrylic monomer derived units, the at least two polyacrylates being bonded to each other by at least one polyethylenic cross-linking agent, wherein the polyethylenic cross-linking agent has an Mn value of greater than 1000 g / mol, and wherein the cross-linked polyacrylate has an Mw of at least 30,000 g / mol.

Description

Field of the Invention

[0001] The present disclosure relates to flowable crosslinked polyacrylates comprising a polyolefinic crosslinking agent and methods of making such materials. Background of the Invention

[0002] Polyacrylates have many applications in coatings, binders, flow improvers, and adhesives. The usefulness of such polymers is driven by their inherent polar nature, as well as the diversity of monomers and the process conditions available for making them, thus providing a high degree of flexibility in their commercial applications. An important class of polyacrylates are those that are crosslinked, thus providing greater processing flexibility and end-use applications.

[0003] Common types of crosslinkable polyacrylates are those that contain a mixture of monofunctional and polyfunctional monomers, which are then cured by a secondary process different from the process used to form the polyacrylate, such as by heating, ultraviolet radiation, or other free-radical generating means. Such compositions are disclosed, for example, in US 2013 / 0273362A1, US 8110280, US7393901, and US 2006 / 0116476A1. However, for example, US 10947423 discloses a crosslinked copolymer composition for oil-resistant adhesives that does not contain a polyfunctional crosslinking agent.

[0004] Also known are crosslinkable polyacrylates having monofunctional acrylic monomers and monomers having a crosslinkable functional group capable of forming a covalent bond with a second crosslinkable functional group of an adjacent functional group when applying curing conditions (such as pressure), as in US 2021 / 0198533A1, which discloses thiol-ene crosslinking and amine-acetoacetoxy crosslinking. In addition, for example, US 10626300 and US9803114 disclose crosslinkable polyacrylates containing a mixture of a solute polymer, monomers, and a crosslinking agent, which are subsequently cured (such as by means of ultraviolet radiation or pressure).

[0005] Known crosslinkable polyacrylates in which a crosslinking reaction occurs between hydroxyl groups from polymers or monomers and isocyanates as crosslinking agents are also known, as disclosed in JP 6986666B2 and JP 6338915B2. For example, the use of other small molecule polyfunctional acrylates is disclosed in US2021 / 0130521A1; US 9447309; and US 9822286; the use of small molecule polyfunctional monomers is also disclosed in US2017 / 0037282A1. In US 9475967, the monomer contains a C6 to C20 olefin side chain as a crosslinkable unit; in US2014 / 0243493A1, the crosslinking agent is polyethylene glycol dimethacrylate. Finally, US 9359528B2 and US 9290682 generally describe the crosslinking agent as a polyfunctional acrylate.

[0006] There is still a need to provide new solutions for useful crosslinkable polyacrylates. The present inventors have herein developed a crosslinked polymer derived from monofunctional acrylic monomers and a well-defined hydrophobic polymeric crosslinking agent having a particularly narrow polydispersity. Since this crosslinked polyacrylate can be manufactured under typical free radical reaction conditions (without secondary processes such as ultraviolet radiation or pressure, etc.), as a means of achieving desired polymer properties, especially desired shear viscosity properties, the influence of different polymerization conditions on the properties of the crosslinked product is further explored. Summary of the Invention Summary of the Invention

[0007] The present disclosure relates to crosslinked polyacrylates comprising the reaction product (or consisting essentially of, or consisting of) of: one or more monofunctional acrylic monomers; and one or more polyolefinic crosslinking agents having at least two reactive dienes and an Mn value greater than 1000 g / mol; wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol.

[0008] The present disclosure also relates to crosslinked polyacrylates comprising at least two polyacrylates (or consisting essentially of, or consisting of) comprising one or more monofunctional acrylic monomer-derived units, the at least two polyacrylates being bonded to each other by at least one polyolefinic crosslinking agent, wherein the at least one polyolefinic crosslinking agent has an Mn value greater than 1000 g / mol, and wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol.

[0009] In any embodiment, the polyolefinic crosslinking agent is selected from the following structures: and combinations thereof, where n and m are integers in the range of 0 to 40, where n + m ≥ 1, and where any one or more of the hydroxyl groups in said structure may be esterified to form an acrylate analogue, and where R is a hydrocarbon group and R' is hydrogen or methyl.

[0010] In any embodiment, the one or more monofunctional acrylic monomers are selected from structures of the formula CH2═CR—C(O)X—R', where R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", where R' is hydrogen or a linear, branched or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched or cyclic hydrocarbon group.

[0011] In addition, in any embodiment, the polyacrylate has a polydispersity (PDI) of 2.4 or less.

[0012] In addition, in any embodiment, the crosslinked polyacrylate has an Mn of at least 20,000 grams per mole.

[0013] In addition, in any embodiment, the crosslinked polyacrylate has an Mw of at least 50,000 grams per mole.

[0014] In addition, in any embodiment, the crosslinked polyacrylate has an Mz of at least 50,000 grams per mole.

[0015] In addition, in any embodiment, the crosslinked polyacrylate has a PDI in the range of 2.5 to 20.

[0016] The present disclosure also relates to a method of forming a crosslinked polyacrylate having an Mw of at least 30,000 grams per mole, which comprises (or consists of, or consists essentially of) combining one or more monofunctional acrylic monomers with a polyolefinic crosslinker having at least two reactive dienes, where: (a) the polyolefinic crosslinker is combined over time; (b) both are combined simultaneously; (c) the monofunctional acrylic monomers are combined over time, or (d) the monofunctional acrylic monomers and the polyolefinic crosslinker are combined with each other over time. Brief Description of the Drawings

[0017] Figure 1 is a representative Williams-Landel-Ferry model diagram for performing time-temperature superposition, where G' and G" are plotted as a function of angular frequency;

[0018] Figure 2is a representative graph of the horizontal shift factors, where the aT values are plotted as a function of temperature;

[0019] Figure 3 is a bar graph of the bulk shear thinning performance (cross exponents) of certain embodiments described herein at equal molar ratios and using only LMA as the monofunctional acrylic monomer (Mz values are shown above each bar);

[0020] Figure 4 is a bar graph of the bulk shear thinning performance (cross exponents) of the certain embodiments at equal molar ratios and using a consistent composition of monofunctional acrylic monomers; and

[0021] Figure 5 is a bar graph that shows, for embodiments using the same crosslinker type and amount, the effect of molecular weight on the cross exponent when using different monofunctional acrylic monomers (Mz values are shown above each bar). Detailed Description Detailed Description of the Invention

[0022] For all of the specification and all of the claims of this invention, when used, the following terms and expressions have the meanings given below.

[0023] As used herein, the term "monomer" or "monofunctional acrylic monomer(s)" refers to a structure of the formula CH2=CR—C(O)X—R', where R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", R' is hydrogen or a linear, branched or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched or cyclic hydrocarbon group. In any embodiment, the linear hydrocarbon group is a C1 or C10 or C21 to C50, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the branched hydrocarbon group is a C4 or C10 or C21 to C40, or C60, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the cyclic hydrocarbon is a C5 or C10 to C20, or C40, or C60, or C80 hydrocarbon group, where the cyclic hydrocarbon can be a polycyclic hydrocarbon group.

[0024] As used herein, the term "polyacrylates" includes acrylates, methacrylates, and other (alkyl) acrylates alkyl esters containing monomer-derived units of the formula: CH2=CR—C(O)X—R', where R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", R' is hydrogen or a linear, branched, or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched, or cyclic hydrocarbon group.

[0025] As used herein, the term "initiator" refers to a chemical compound that generates free radicals upon heating and can be used to effect the formation of chemical bonds between monomers and / or one or more crosslinkers.

[0026] As used herein, the phrase "reactive diene" refers to a diene that is capable of forming bonds with other molecules under the same conditions as those used to form the polyacrylates described herein.

[0027] As used herein, in tables and throughout the specification and claims, the polydispersity index or "PDI" is equivalent to the ratio of Mw / Mn.

[0028] As used herein, all Mn, Mw, and Mz values used and referred to herein are calculated by gel permeation chromatography techniques (GPC) as described below.

[0029] As used herein, the term "crosslinker" refers to a chemical compound containing at least two free radical-reactive units, such as methacrylate, acrylate, and / or diene. Most preferably, the crosslinkers described herein are polyolefinic crosslinkers.

[0030] As used herein, the term "polyolefin" refers to a polymer composed of one or more types of olefin monomers. "Olefin" is a linear, branched, or cyclic compound of carbon and hydrogen having at least one double bond. Most preferably, the polyolefin polymers described herein comprise olefin-derived monomers selected from C2 to C10, or C15, or C20, or C25, or C30, or C50 olefins. For the purposes of this specification and the appended claims, when a polymer or copolymer is referred to as comprising an olefin ("olefinic"), the olefin present in such a polymer or copolymer is the polymerized form of that olefin. For example, when a copolymer is said to have an "isoprene" content of 55 wt% to 95 wt%, it is to be understood that the monomer-derived units (or "monomer units") in the copolymer are derived from isoprene in a polymerization reaction and that the monomer units are present at 55 wt% to 95 wt% based on the weight of the copolymer. "Polymer" has two or more identical or different monomer units. "Homopolymer" is a polymer having the same monomer units; "copolymer" is a polymer having two or more different monomer units from each other. The "different" used to refer to monomer units means that the monomer units differ from each other by at least one atom or are isomerically different. Thus, for example, a polyethylene homopolymer is derived from a C2 olefin and an ethylene-propylene copolymer is derived from a C2 olefin and a C3 olefin.

[0031] As used herein, when a polymer is referred to as a "partially or fully saturated polymer" or "partially or fully hydrogenated", such a polymer or copolymer is the polymerized form of an olefin and the polymer has been partially or fully saturated (such as by hydrogenation) after monomer polymerization. In any embodiment, a fully saturated or fully hydrogenated polymer may contain a residual amount of unsaturation, such as less than 0.1 wt% of the polymer may have unsaturation.

[0032] As used herein, the term "hydrocarbon" refers to a compound of hydrogen and carbon atoms, such as a compound of 10 carbon atoms ("C10"), 100 carbon atoms ("C100"), etc. "Heteroatom" is an atom other than carbon or hydrogen, and a hydrocarbon may also contain one or more heteroatoms or heteroatom-containing groups, such as oxygen (O), hydroxyl (OH), carboxyl (O═C), halogen, especially chlorine and fluorine, amino, alkoxy, mercapto, alkyl mercapto, nitro, nitroso, sulfoxy, etc. "Hydrocarbyl" is a hydrocarbon radical, that is, it lacks one or more hydrogen and / or carbon atoms so that it is a group bonded to another compound or group and is otherwise the same as a hydrocarbon. The term "hydrocarbyl" includes "alkyl", "alkenyl", "alkynyl", and "aryl" as defined herein.

[0033] As used herein, the term "reagent" refers to chemical compounds that are combined with each other to form polyacrylates and / or crosslinked polyacrylates. For example, the reagents required to form a crosslinked polyacrylate are at least a polyolefin crosslinking agent and a monofunctional acrylic monomer that forms a polyacrylate.

[0034] As used herein, the phrase "over time" means from a starting time until a final time when all the reagents are combined as specified, and the combination of the reagents occurs gradually, either continuously or in fractions. For example, four 1 / 4 portions of reagent A are added to another reagent in 20-minute increments until all of reagent A has been combined over a period of 60 minutes; or reagent A is gradually added to another reagent and metered in continuously over a period of 60 minutes.

[0035] As used herein, the terms "fractional" and "fractionally" mean adding the reagents in portions over time until all the reagents are combined with each other; for example, four 1 / 4 portions of reagent A are added to another reagent in 20-minute increments until all of reagent A has been combined after 60 minutes, thereby combining reagent A fractionally.

[0036] As used herein, the term "simultaneously" means adding two or more reagents to each other in a very short time, such as within less than 1% or 0.1% of the total time allowed for the reagents to react with each other.

[0037] It is to be understood that any upper and lower limits of amounts, ranges, and ratios given herein can be combined independently.

[0038] It is also to be understood that the preferred features of each aspect of the present disclosure are considered to be the preferred features of every other aspect of the present disclosure. Accordingly, the preferred and more preferred features of one aspect of the present disclosure can be combined independently with the other preferred and / or more preferred features of the same or different aspects of the present disclosure.

[0039] The present invention relates to a crosslinked polyacrylate, where the crosslinker is a polymeric linear or branched hydrophobic molecule having a reactive diene (such as a dimethacrylate) so that it can form bonds with two or more polyacrylate or other diene-containing molecules. Surprisingly, the incorporation of such polymeric crosslinkers, especially those derived from narrow PDI hydrogenated polybutadiene and / or polyfarnesene, results in polymer products with improved bulk shear thinning compared to small molecule dimethacrylate crosslinkers (such as 1,6 - hexanediol dimethacrylate or "1,6 - hexyl") or in the absence of any crosslinker. Changing the polymerization conditions and incorporating comonomers with different degrees of polarity also leads to significant and unexpected improvements in the shear thinning properties. The ability to modulate the shear thinning behavior of polyacrylates beyond monomer selection is beneficial for improving processing properties across multiple application areas, including adhesives, flow improvers, coatings, and adhesives.

[0040] As described herein, a mixture of a monofunctional acrylic monomer and a polymeric linear or branched hydrophobic molecule having a reactive crosslinkable diene is reacted in one or more solvents such as toluene and / or 2 - butanol to produce a branched polyacrylate. Several different methods are employed to vary the initiation rate by the reaction temperature and the order of addition of the crosslinker and the monofunctional monomer.

[0041] The crosslinked polyacrylates described herein can be characterized by gel permeation chromatography (GPC) and rheology. The polymer flow temperature, cross exponent (a), and zero - shear viscosity (η0) are determined using oscillatory rheology by applying the Cox - Merz rule. The polymer flow temperature represents the temperature at which the polymer begins to flow easily under gravity. The cross exponent and zero - shear viscosity, further described below, are determined by fitting the generalized cross model to the complex viscosity of each material as a function of temperature. A lower cross exponent indicates higher shear thinning. Finally, the zero - shear viscosity is an assessment of the viscosity (or flowability) of the bulk material. Ideally, the crosslinked polyacrylates described herein are flowable, rather than networks, films, or gels. The GPC method is described in the Examples section below.

[0042] Accordingly, in any embodiment, the crosslinked polyacrylate comprises the reaction product of one or more monofunctional acrylic monomers; and one or more polyolefinic crosslinking agents having at least two reactive dienes and an Mn value greater than 1000 g / mol; wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol. These crosslinked polyacrylates are flowable at temperatures from 0 to 200 °C (as defined by the polymer flow temperature, determined as described in the Examples section), and this flowability can be tailored by the choice of monomers, the choice of crosslinking agent, the process conditions used when combining the reagents to form the crosslinked polyacrylate, or combinations thereof.

[0043] In any embodiment, the crosslinked polyacrylate has a crosslinking index of less than 1.0, or less than 0.80, or less than 0.70, or less than 0.60, or less than 0.55, or less than 0.50. In any embodiment, the crosslinked polyacrylate has a crosslinking index in the range from 0.20 or 0.30 to 0.50, or 0.55, or 0.60, or 0.65, or 0.70, or 0.80, or 1.0. In any embodiment, the crosslinked polyacrylate of the present invention has a lower crosslinking index than the corresponding non-crosslinked polyacrylate or the same polyacrylate crosslinked with a lower molecular weight crosslinking agent (Mn less than 500 g / mol or less than 400 g / mol).

[0044] In any embodiment, the crosslinked polyacrylate has an Mw of at least 30,000 g / mol, or 50,000 g / mol, or 60,000 g / mol, or at least 70,000 g / mol, or at least 80,000 g / mol, or at least 100,000 g / mol. In any embodiment, the crosslinked polyacrylate has an Mw value in the range from 30,000 g / mol, or 50,000, or 60,000, or 70,000, or 80,000, or 100,000 g / mol to 200,000, or 300,000, or 400,000, or 500,000, or 800,000 g / mol.

[0045] In any embodiment, the crosslinked polyacrylate has an Mz of at least 50,000 g / mol, or 80,000 g / mol, or 100,000 g / mol, or at least 120,000 g / mol, or at least 150,000 g / mol, or at least 200,000 g / mol, or at least 300,000 g / mol, or at least 400,000 g / mol, or at least 500,000 g / mol. In any embodiment, the crosslinked polyacrylate has an Mz value in the range from 50,000, or 80,000, or 100,000, or 120,000, or 150,000, or 200,000, or 300,000, or 400,000 or 500,000 g / mol to 600,000, or 700,000, or 800,000, or 900,000, or 1,000,000, or 1,500,000, or 2,000,000, or 3,000,000, or 4,000,000 g / mol.

[0046] In any embodiment, the crosslinked polyacrylate has a PDI greater than 2.4, or greater than 2.5, or greater than 3.0, or greater than 4.0, or greater than 5.0. In any embodiment, the crosslinked polyacrylate has a PDI in the range from 2.4, or 2.5, or 3.0, or 4.0, or 5.0 to 10, or 12, or 16, or 18, or 20.

[0047] In any embodiment, the crosslinked polyacrylate has a zero shear-viscosity (20 °C) of at least 500 Pa·s, or at least 600 Pa·s, or at least 800 Pa·s, or at least 1000 Pa·s; in any embodiment, the crosslinked polyacrylate has a zero shear-viscosity (20 °C) in the range from 500, or 600, or 800, or 1000 Pa·s to 10,000, or 20,000, or 60,000, or 100,000, or 400,000, or 600,000, or 1,000,000, or 1,500,000, or 2,000,000, or 2,500,000, or 3,000,000, or 3,500,000 Pa·s.

[0048] In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 0.1 rad / s) of at least 10 Pa, or at least 20, or at least 100 Pa, or at least 1000 Pa, or at least 5000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 0.1 rad / s) in the range from 10, or 20, or 100, or 1000, or 5000 Pa to 10,000, or 20,000, or 30,000, or 40,000, or 50,000 Pa.

[0049] In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 100 rad / s) of at least 15,000 Pa, or at least 30,000 Pa, or at least 120,000 Pa, or 140,000 Pa, or 160,000 Pa, or 200,000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 100 rad / s) in the range from 15,000, or 30,000, or 120,000, or 140,000, or 160,000, or 200,000 Pa to 400,000, or 450,000, or 500,000, or 600,000, or 800,000, or 1,000,000, or 2,000,000, or 3,000,000, or 4,000,000, or 5,000,000 Pa.

[0050] In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 0.1 rad / s) of at least 20 Pa, or at least 100 Pa, or at least 1000 Pa, or at least 5000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 0.1 rad / s) in the range from 20, or 100, or 1000, or 5000 Pa to 10,000, or 20,000, or 30,000, or 40,000 or 80,000, or 100,000, or 150,000 Pa.

[0051] In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 100 rad / s) of at least 3000 Pa, or 10,000 Pa, or 20,000 Pa, or 50,000 Pa, or 100,000 Pa, or 120,000 Pa, or 140,000 Pa, or 160,000 Pa, or 200,000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 100 rad / s) in the range from 3000, or 10,000, or 20,000, or 50,000, or 100,000, or 120,000, or 140,000, or 160,000, or 200,000 Pa to 400,000, or 450,000, or 500,000, or 600,000, or 800,000, or 1,000,000, or 1,400,000, or 1,600,000, or 1,800,000, or 2,000,000 Pa.

[0052] In any embodiment, the crosslinked polyacrylate has a polymer flow temperature in the range from 0, or 20, or 30, or 40 °C to 90, or 100, or 140, or 160, or 200 °C.

[0053] In any embodiment, the crosslinked polyacrylate has a weight average monomer solubility parameter (MPa 1 / 2 from 5 or 10 MPa 1 / 2 to 20 or 25 or 30 MPa 1 / 2 ). In any embodiment, the crosslinked polyacrylate has a Flory - Fox monomer glass transition temperature T g (°C) in the range from - 60, or - 50, or - 40, or - 30 °C to 20, or 30, or 50, or 70, or 100 °C. In any embodiment, the crosslinked polyacrylate has a Flory - Fox polymer glass transition temperature T g (°C) in the range from - 60, or - 50, or - 20 °C to 20, or 30, or 40, or 50, or 60, or 70, or 100, or 110 °C.

[0054] The identity and properties of the polyolefin crosslinker can also be customized to suit the desired use. In any embodiment, the polyolefin crosslinker is a hydrophobic compound having an Mn value of at least 1000 g / mol or 2000 g / mol and having at least two reactive dienes. In any embodiment, the polyolefin crosslinker is partially or fully hydrogenated. Additionally, in any embodiment, polar groups such as those containing nitrogen and / or oxygen are substantially absent in the polyolefin crosslinker, except for the two reactive dienes, in which case such polar groups may be present, such as acrylate groups.

[0055] In any embodiment, the polyolefin crosslinker has an Mn value of at least 1000 g / mol, or at least 2000 g / mol, or at least 3000 g / mol. In any embodiment, the polyolefin crosslinker has an Mn value in the range from 1000, or 2000, or 3000 g / mol to 4000, or 5000, or 6000 g / mol. In any embodiment, the polyolefin crosslinker has a PDI of 2.2, or 2, or 1.9, or 1.8 or less.

[0056] In any embodiment, the polyolefin crosslinker is a polyolefin homopolymer or copolymer having at least two reactive dienes and is formed from olefin monomers selected from C2 to C10, or C15, or C20, or C25, or C30, or C50 olefins, wherein the homopolymer or copolymer is linear or branched, and wherein the branching may include C1 to C50 hydrocarbon branches. In any embodiment, the polyolefin crosslinker is any desired molar ratio combination of polybutadiene or polyfarnesene or both, which has at least two reactive dienes. In any embodiment, the polybutadiene or polyfarnesene, except for the at least two reactive dienes, is hydrogenated.

[0057] In any embodiment, the polyolefin crosslinker is selected from the following structures: and combinations thereof, wherein n and m are integers in the range from 1, or 2, or 4 to 10, or 20, or 30, or 40, and wherein any one or more of the hydroxyl groups in the structure may be esterified to form an acrylate analogue, and wherein R is a hydrocarbon group and R' is hydrogen or methyl.

[0058] The identity and properties of the monofunctional acrylic monomers can also be selected and / or customized to suit the desired crosslinked polyacrylate. One or a combination of any type of monofunctional acrylic monomer can be selected and combined to form the desired crosslinked polyacrylate. In any embodiment, the one or more monofunctional acrylic monomers are selected from the structure represented by the formula CH2=CR—C(O)X—R', where R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", R' is hydrogen or a linear, branched or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched or cyclic hydrocarbon group. In any embodiment, the linear hydrocarbon group is a C1 or C10 or C21 to C50, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the branched hydrocarbon group is a C4 or C10 or C21 to C40, or C60, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the cyclic hydrocarbon is a C5 or C10 to C20, or C40, or C60, or C80 hydrocarbon group, where the cyclic hydrocarbon can be a polycyclic hydrocarbon group.

[0059] In any embodiment, the one or more monofunctional acrylic monomers are selected from lauryl acrylate, n-butyl acrylate, benzyl acrylate, acrylic acid, lauryl methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, polybutadiene methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate, and poly(ethylene glycol) methacrylate and combinations thereof.

[0060] In a particular embodiment is a crosslinked polyacrylate comprising a reaction product of one or more monofunctional acrylic monomers; one or more polyolefin crosslinkers having at least two reactive dienes and an Mn value greater than 1000 g / mol; one or more initiators and one or more chain transfer agents, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol.

[0061] The crosslinked polyacrylates of the present invention can be described by any combination of the features disclosed herein. For example, in any embodiment is a crosslinked polyacrylate comprising a reaction product of one or more monofunctional acrylic monomers; one or more polyolefin crosslinkers having at least two reactive dienes and an Mn value greater than 1000 g / mol; one or more initiators and one or more chain transfer agents, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol and a zero shear viscosity (20 to 110 °C) in the range of 500 Pa-s to 3,500,000 Pa-s.

[0062] In another embodiment is a crosslinked polyacrylate comprising the reaction product of one or more monofunctional acrylic monomers; one or more polyolefinic crosslinkers having at least two reactive dienes and an Mn value greater than 1000 g / mol; one or more initiators and one or more chain transfer agents, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol and a polymer flow temperature in the range of 20 °C to 200 °C.

[0063] The polyacrylates and crosslinked polyacrylates according to the present disclosure can be obtained by any suitable means by combining the reagents with each other, for example by solution polymerization, bulk polymerization or emulsion polymerization, and in any embodiment by free radical solution polymerization. These methods are listed in Ullmann’s ENCYCLOPEDIA OF INDUSTRIAL CHEMISTRY, Sixth Edition (Wiley). In addition to conventional free radical polymerization methods, related controlled free radical polymerization methods such as ATRP (Atom Transfer Radical Polymerization), NMP (Nickel Trioxide-Mediated Polymerization) or RAFT (Reversible Addition Fragmentation Chain Transfer) can also be used to prepare the polyacrylates and crosslinked polyacrylates described herein. Typical free radical polymerization uses a polymerization initiator and, in any embodiment, a molecular weight regulator.

[0064] Initiators that can be used include, but are not limited to, azo initiators such as 1,1-azobiscyclohexanecarbonitrile and 2,2′-azobis(2-methylpropionitrile), and other azo compounds of the general formula R1—N═N—R 2 wherein R 1 and R 2may be an alkyl or aryl group; and peroxides such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauroyl peroxide, tert-butyl peroxy-2-ethylhexanoate, ketone peroxide, tert-butyl peroxycaprylate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, benzoyl peroxide, tert-butyl peroxybenzoate, tert-butylperoxyisopropylcarbonate, 2,5-bis(2-ethylhexanoate), tert-butylperoxy-3,5,5-trimethylhexanoate, dicumyl peroxide, 1,1-bis(tert-butylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, cumylhydroperoxide, tert-butyl hydroperoxide, bis(4-tert-butylcyclohexyl) peroxydicarbonate and other peroxides of the general formula R 1 —O-O—R 2 wherein R 1 and R 2 may be an alkyl or aryl group; mixtures of two or more of these compounds with each other, and mixtures of any one of these compounds with other free-radical-forming compounds.

[0065] Such initiators can be used alone or in combination. In any embodiment, they are combined with the reagents in the range of 0.05 to 10 wt% or in the range of 3 to 8 wt% of all the reagents to form a crosslinked polyacrylate. In any embodiment, the initiator is combined with the reagents in a molar ratio relative to the polyolefin crosslinking agent in the range of 0.2 to 1.6, or 0.3 to 1.4, or 0.3 to 1, or 0.3 to 0.8 to form a crosslinked polyacrylate.

[0066] The initiators have a measurable half-life based on the solvent system and temperature in which they are located. Initiators having different half-lives can be combined to form the crosslinked polyacrylates described herein. It is particularly desirable to carry out the free-radical reactions described herein using the initiators by adapting the temperature and / or solvent to the initiator used to obtain a desired half-life to reduce, for example, gelation in the reaction. In any embodiment, the reagents are combined with the initiator, wherein the combination is carried out at a temperature such that the initiator half-life is in the range of 1 to 5, or 8, or 10 hours.

[0067] In any embodiment, a chain transfer agent (CTA) or a molecular weight regulator can be combined with the reagents to form a crosslinked polyacrylate. Chain transfer agents include, but are not limited to, mercapto compounds such as tert-dodecyl mercaptan, dialkyl sulfides, dialkyl disulfides, and / or diaryl sulfides such as di-n-butyl sulfide, di-n-octyl sulfide, diphenyl sulfide, thiodiglycol, ethylthioethanol, diisopropyl disulfide, di-n-butyl disulfide, di-n-hexyl disulfide, diacetyl disulfide, diethanol disulfide, di-tert-butyl trisulfide, and dimethyl sulfoxide, ethyl thioglycolate, 2-ethylhexyl thioglycolate, cysteine, 2-mercaptoethanol, 3-mercapto-1-propanol, 3-mercapto-1,2-propanediol, 1,4-mercaptobutanol, thioglycolic acid, 3-mercaptopropionic acid, mercaptosuccinic acid, thiodiglycerol, thioacetic acid, thiourea, and alkyl mercaptans such as n-butyl mercaptan, n-hexyl mercaptan, and n-dodecyl mercaptan. Non-mercaptans such as dimeric α-methylstyrene, (2,4-diphenyl-4-methyl-1-pentene), enol ethers of aliphatic and / or alicyclic aldehydes, terpenes, beta-terpinene, terpinolene, 1,4-cyclohexadiene, 1,4-dihydronaphthalene, 1,4,5,8-tetrahydronaphthalene, 2,5-dihydrofuran, 2,5-dimethylfuran, and / or 3,6-dihydro-2H-pyran can also be used.

[0068] Such CTAs can be used alone or in combination. In any embodiment, the CTA is combined with the reagents in the range of 0.05 to 10 wt% or in the range of 3 to 8 wt% of all the reagents to form a crosslinked polyacrylate. In any embodiment, the CTA is combined with the reagents in a molar ratio relative to the initiator in the range of 1 to 5, or 1.2 to 4, or 1.4 to 3.5 to form a crosslinked polyacrylate.

[0069] As mentioned above, it is desired to combine the reagents in a solvent or solvent mixture and carry out the radical polymerization and crosslinking reactions described herein. Preferred solvents include aromatic hydrocarbons such as toluene, xylene; esters such as butyl acetate, ethyl acetate, propyl acetate; ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone or cyclohexanone; alcohols such as isopropyl alcohol, n-propyl alcohol, isobutyl alcohol; ethers such as glycol monomethyl ethers, glycol monoethyl ethers, glycol monobutyl ethers; aliphatic compounds such as pentane, hexane, cycloalkanes and substituted cycloalkanes such as cyclohexane, and mixtures of any of these.

[0070] Thus in any embodiment, the crosslinked polyacrylate described herein is made by a process comprising combining one or more monofunctional acrylic monomers; one or more polyolefinic crosslinking agents having at least two reactive dienes and an Mn value greater than 1000 g / mol, optionally one or more initiators and optionally one or more chain transfer agents, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol. These reagents are preferably combined in a solvent or solvent mixture having any desired volume ratio or mass ratio. The manner in which the reagents are combined (simultaneously, continuously and gradually, or stepwise) and the conditions (such as temperature and solvent) under which the reagents are combined will affect the properties of the final crosslinked polyacrylate.

[0071] There are several ways to add or combine the reagents with each other to form the crosslinked polyacrylate described herein. In any embodiment is a process for forming a crosslinked polyacrylate having an Mw of at least 30,000 g / mol, which comprises combining one or more monofunctional acrylic monomers with a polyolefinic crosslinking agent having at least two reactive dienes, wherein: (a) the polyolefinic crosslinking agent is combined over time; (b) both are combined simultaneously; (c) the monofunctional acrylic monomer is combined over time, or (d) the monofunctional acrylic monomer and the polyolefinic crosslinking agent are combined with each other over time.

[0072] Desirably, a flowable crosslinked polyacrylate is formed that is not a gel and has the above molecular weight and zero-shear viscosity characteristics. In any embodiment, the method further includes incorporating an initiator. In any embodiment, the initiator is incorporated simultaneously with the monofunctional acrylic monomer and the polyolefin crosslinker. In another embodiment, the initiator is incorporated continuously or stepwise with the monofunctional acrylic monomer and the polyolefin crosslinker over time. The identity of the initiator and the temperature at which it is incorporated can control the final properties of the crosslinked polyacrylate. In any embodiment, the initiator is incorporated with the monofunctional acrylic monomer and the polyolefin crosslinker over a time period, such as in the range from 10 to 100, or 200, or 300 minutes. Taking into account the temperature dependence of initiator behavior, in any embodiment, the incorporation is carried out at a temperature such that the half-life of the initiator is in the range from 1 to 5, or 8, or 10 hours.

[0073] In any embodiment, the free radical polymerization or the incorporation of the reagents described herein is carried out at a temperature within a lower limit of 20, or 25, or 30, or 35, or 40, or 45, or 50, or 55, or 60 °C to an upper limit of 95, or 100, or 105, or 110, or 120, or 140 °C.

[0074] In any embodiment of the methods described herein, the incorporation of the reagents is carried out at a temperature of 90 °C or higher. In any embodiment, the incorporation is carried out at a temperature less than 90 °C. In any embodiment, the incorporation is carried out at a temperature in the range from 88 to 95 °C. In any embodiment, the incorporation is carried out at a temperature in the range from 65 to 88 °C.

[0075] The time over which the reagents are added to each other can be a factor in the methods described herein. Thus in any embodiment, the acrylic monomer and the polyolefin crosslinker (or the acrylic monomer or the polyolefin crosslinker) are incorporated continuously over a time period in the range from 10 to 100, or 200, or 300 minutes. Also in any embodiment, the acrylic monomer and the polyolefin crosslinker (or the acrylic monomer or the polyolefin crosslinker) are incorporated in portions over a time period in the range from 10 to 100, or 200, or 300 minutes.

[0076] In any embodiment, the polyolefin crosslinker is incorporated in an amount of 0.1 to 5, or 10, or 12, or 16, or 20 weight % of the polyolefin crosslinker, one or more monofunctional acrylic monomers, and the initiator. In any embodiment, the monofunctional acrylic monomer is incorporated in an amount of 1, or 4, or 6, or 10 weight %, up to 20, or 30, or 40, or 50, or 60, or 70, or 80, or 84, or 88, or 90, or 95, or 99.9 weight % of the combined reagents (acrylic monomer, polyolefin crosslinker, and other reagents such as the initiator).

[0077] Thus, in any embodiment, there is a crosslinked polyacrylate that comprises at least two polyacrylates each comprising one or more derived units of a monofunctional acrylic monomer, the at least two polyacrylates being bonded to each other by at least one polyolefinic crosslinker, wherein the at least one polyolefinic crosslinker has an Mn value greater than 1000 g / mol and wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol. If there is more than one polyolefinic crosslinker, they may differ in terms of Mn and polymer structure (linear, branched, copolymer, etc.). In this way, a macromolecular composition having different components derived from monomer units is described, where the crosslinker is one unit and the polyacrylate is composed of many units that may be the same or different in identity. Also described in this way, it is to be understood that the polyolefinic crosslinker, being part of the macromolecule, is reactive, meaning that at least two of its reactive dienes have formed bonds with each of the two polyacrylates.

[0078] In another embodiment, there is also a crosslinked polyacrylate, each polyacrylate comprising one or more monofunctional acrylic monomers to form at least two polymer chains bonded to each other by at least one polyolefinic crosslinker, wherein the polyolefinic crosslinker has an Mn value greater than 1000 g / mol, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol and a zero-shear viscosity (20 °C) in the range of 500 Pa·s to 3,500,000 Pa·s.

[0079] In another embodiment, there is also a crosslinked polyacrylate, each polyacrylate comprising one or more monofunctional acrylic monomers to form at least two polymer chains bonded to each other by at least one polyolefinic crosslinker, wherein the polyolefinic crosslinker has an Mn value greater than 1000 g / mol, wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol and a polymer flow temperature in the range of 20 °C to 200 °C.

[0080] Desirably, no separate method step is required to effect complete reaction of the acrylic monomers and crosslinker described herein after combining the reagents, such as another heating step, pressure, UV or other radiation exposure, or addition of other chemical reagents. Thus, in any embodiment, there is no additional step for curing or effecting crosslinking.

[0081] The properties of the crosslinked polyacrylate described in this macromolecular embodiment are the same as those described elsewhere in the specification. In any embodiment, the crosslinked polyacrylate has a crosslinking index less than 1.0, or less than 0.80, or less than 0.70, or less than 0.60, or less than 0.55, or less than 0.50. In any embodiment, the crosslinked polyacrylate has a crosslinking index in the range from 0.20, or 0.30 to 0.50, or 0.55, or 0.60, or 0.65, or 0.70, or 0.80, or 1.0. In any embodiment, the crosslinking index of the crosslinked polyacrylate of the present invention is lower than that of the corresponding non-crosslinked polyacrylate or the same polyacrylate crosslinked with a lower molecular weight crosslinking agent (Mn less than 500 g / mol or less than 400 g / mol).

[0082] In any embodiment, the crosslinked polyacrylate has an Mw of at least 30,000 g / mol, or 50,000 g / mol, or 60,000 g / mol, or at least 70,000 g / mol, or at least 80,000 g / mol, or at least 100,000 g / mol. In any embodiment, the crosslinked polyacrylate has an Mw value in the range from 30,000 g / mol, or 50,000, or 60,000, or 70,000, or 80,000, or 100,000 g / mol to 200,000, or 300,000, or 400,000, or 500,000, or 800,000 g / mol.

[0083] In any embodiment, the crosslinked polyacrylate has an Mz of at least 50,000 g / mol, or 80,000 g / mol, or 100,000 g / mol, or at least 120,000 g / mol, or at least 150,000 g / mol, or at least 200,000 g / mol, or at least 300,000 g / mol, or at least 400,000 g / mol, or at least 500,000 g / mol. In any embodiment, the crosslinked polyacrylate has an Mz value in the range from 50,000, or 80,000, or 100,000, or 120,000, or 150,000, or 200,000, or 300,000, or 400,000 or 500,000 g / mol to 600,000, or 700,000, or 800,000, or 900,000, or 1,000,000, or 1,500,000, or 2,000,000, or 3,000,000, or 4,000,000 g / mol.

[0084] In any embodiment, the crosslinked polyacrylate has a PDI greater than 2.4, or greater than 2.5, or greater than 3.0, or greater than 4.0, or greater than 5.0. In any embodiment, the crosslinked polyacrylate has a PDI in the range from 2.4, or 2.5, or 3.0, or 4.0, or 5.0 to 10, or 12, or 16, or 18, or 20.

[0085] In any embodiment, the crosslinked polyacrylate has a weight-average monomer solubility parameter in the range from 5 or 10 MPa 1 / 2 to 20 or 25 or 30 MPa 1 / 2 (MPa 1 / 2 ). In any embodiment, the crosslinked polyacrylate has a Flory-Fox monomer glass transition temperature T g (°C) in the range from -60, or -50, or -40, or -30 °C to 20, or 30, or 50, or 70, or 100 °C. In any embodiment, the crosslinked polyacrylate has a Flory-Fox polymer glass transition temperature T g (°C) in the range from -60, or -50, or -20 °C to 20, or 30, or 40, or 50, or 60, or 70, or 100, or 110 °C.

[0086] As described above, the identity and nature of the polyolefin crosslinker can also be tailored to suit the desired crosslinked polyacrylate. In any embodiment, the polyolefin crosslinker is a hydrophobic compound having an Mn value of at least 1000 g / mol or 2000 g / mol and having at least two reactive dienes. In any embodiment, the polyolefin crosslinker is partially or fully hydrogenated. Additionally, in any embodiment, there are substantially no polar groups in the polyolefin crosslinker, such as those containing nitrogen and / or oxygen, except for the two reactive dienes, in which case such polar groups may be present, such as acrylate groups.

[0087] In any embodiment, the polyolefin crosslinker has an Mn value of at least 1000 g / mol, or at least 2000 g / mol, or at least 3000 g / mol. In any embodiment, the polyolefin crosslinker has an Mn value in the range from 1000, or 2000, or 3000 g / mol to 4000, or 5000, or 6000 g / mol. In any embodiment, the polyolefin crosslinker has a PDI of 2.2, or 2, or 1.9, or 1.8 or less.

[0088] In any embodiment, the polyolefin crosslinker is a polyolefin homopolymer or copolymer having at least two reactive dienes and is formed from olefin monomers selected from C2 to C10, or C15, or C20, or C25, or C30, or C50 olefins, wherein the homopolymer or copolymer is linear or branched, and wherein the branching may comprise C1 to C50 hydrocarbon branches. In any embodiment, the polyolefin crosslinker is any desired molar ratio combination of polybutadiene or polyfarnesene-derived groups or both,

[0089] In any embodiment, the polyolefin crosslinker is selected from the following structures: and combinations thereof, wherein n and m are integers in the range from 1, or 2, or 4 to 10, or 20, or 30, or 40, and wherein any one or more of the hydroxyl groups in the structure may be esterified to form acrylate analogs, and wherein R is a hydrocarbon group and R' is hydrogen or methyl.

[0090] In any embodiment described as a macromolecule, the one or more monofunctional acrylate monomer-derived units are selected from the free radical structures represented by the following formulas: wherein R' is hydrogen or methyl, and R is hydrogen or a linear, branched or cyclic hydrocarbon group, and n is an integer from 10 to 1000, or 4000, or 6000, or 8000, or 10,000. In any embodiment, the linear hydrocarbon group is a C1 or C10 or C21 to C50, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the branched hydrocarbon group is a C4 or C10 or C21 to C40, or C60, or C80, or C100, or C200, or C300, or C400 hydrocarbon group; in any embodiment, the cyclic hydrocarbon is a C5 to C20, or C40, or C60, or C80 hydrocarbon group, wherein the cyclic hydrocarbon may be a polycyclic hydrocarbon group.

[0091] In any embodiment described as a macromolecule, the one or more monofunctional acrylate monomer-derived units are selected from the free radicals of lauryl acrylate, n-butyl acrylate, benzyl acrylate, acrylic acid, lauryl methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, polybutadiene methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate, and poly(ethylene glycol) methacrylate and combinations thereof.

[0092] As mentioned above, in any embodiment, the crosslinked polyacrylate has a zero-shear viscosity (20 °C) of at least 500 Pa·s, or at least 600 Pa·s, or at least 800 Pa·s, or at least 1000 Pa·s; in any embodiment, the crosslinked polyacrylate has a zero-shear viscosity (20 °C) in the range from 500, or 600, or 800, or 1000 Pa·s to 10,000, or 20,000, or 60,000, or 100,000, or 400,000, or 600,000, or 1,000,000, or 1,500,000, or 2,000,000, or 2,500,000, or 3,000,000, or 3,500,000 Pa·s.

[0093] In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 0.1 rad / s) of at least 10 Pa, or at least 20, or at least 100 Pa, or at least 1000 Pa, or at least 5000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 0.1 rad / s) in the range from 10, or 20, or 100, or 1000, or 5000 Pa to 10,000, or 20,000, or 30,000, or 40,000, or 50,000 Pa.

[0094] In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 100 rad / s) of at least 15,000 Pa, or at least 30,000 Pa, or at least 120,000 Pa, or 140,000 Pa, or 160,000 Pa, or 200,000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (20 °C, 100 rad / s) in the range from 15,000, or 30,000, or 120,000, or 140,000, or 160,000, or 200,000 Pa to 400,000, or 450,000, or 500,000, or 600,000, or 800,000, or 1,000,000, or 2,000,000, or 3,000,000, or 4,000,000, or 5,000,000 Pa.

[0095] In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 0.1 rad / s) of at least 20 Pa, or at least 100 Pa, or at least 1000 Pa, or at least 5000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 0.1 rad / s) in the range from 20, or 100, or 1000, or 5000 Pa to 10,000, or 20,000, or 30,000, or 40,000 or 80,000, or 100,000, or 150,000 Pa.

[0096] In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 100 rad / s) of at least 3000 Pa, or 10,000 Pa, or 20,000 Pa, or 50,000 Pa, or 100,000 Pa, or 120,000 Pa, or 140,000 Pa, or 160,000 Pa, or 200,000 Pa. In any embodiment, the crosslinked polyacrylate has a G" value (110 °C, 100 rad / s) in the range from 3000, or 10,000, or 20,000, or 50,000, or 100,000, or 120,000, or 140,000, or 160,000, or 200,000 Pa to 400,000, or 450,000, or 500,000, or 600,000, or 800,000, or 1,000,000, or 1,400,000, or 1,600,000, or 1,800,000, or 2,000,000 Pa.

[0097] In any embodiment, the crosslinked polyacrylate has a polymer flow temperature in the range from 20, or 30, or 40 °C to 90, or 100, or 140, or 160, or 200 °C. For crosslinked polyacrylates with a higher polymer flow temperature, such as those with a polymer flow temperature greater than 120 or 140 °C, rheological measurements are carried out at 110 °C, and these zero-shear viscosities and G" are in the same ranges as those measured at 20 °C as specified above.

[0098] In any embodiment, the choice of monofunctional acrylic monomer can affect the polymer flow temperature. However, even for the same monofunctional acrylic monomer, the incorporation of polyolefin crosslinkers tends to make the polymer flow temperature higher relative to the use of 1,6 - hexanediol dimethacrylate (1,6 - hexyl) as the crosslinker.

[0099] In addition, relative to similar conditions and using 1,6 - hexanediol dimethacrylate (1,6 - hexyl) as a cross - linker, combining the polyolefin cross - linker with the one or more monofunctional acrylic monomers can in some cases reduce the cross - linking index of the cross - linked polyacrylate. Additional Embodiments

[0100] Additionally or alternatively, the present disclosure may include any one or more of the following numbered embodiments:

[0101] Embodiment 1. A cross - linked polyacrylate comprising at least two polyacrylates (or consisting of, or consisting essentially of) comprising one or more monofunctional acrylic monomer - derived units, wherein the at least two polyacrylates are bonded to each other by at least one polyolefin cross - linker, wherein the at least one polyolefin cross - linker has an Mn value greater than 1000 g / mol, and wherein the cross - linked polyacrylate has an Mw of at least 30,000 g / mol.

[0102] Embodiment 2. The cross - linked polyacrylate of Embodiment 1, wherein the polyolefin cross - linker comprises a polyolefin homopolymer or copolymer having at least two reactive dienes and is formed from olefin monomers selected from C2 to C50 olefins, wherein the homopolymer or copolymer is linear or branched, and wherein the branching may comprise C1 to C50 hydrocarbon branches.

[0103] Embodiment 3. The cross - linked polyacrylate of Embodiment 1 or 2, wherein the polyolefin cross - linker has a PDI of 2.2 or less.

[0104] Embodiment 4. The cross - linked polyacrylate of any of the foregoing numbered embodiments, wherein the polyolefin cross - linker has an Mn value in the range of 1000 to 6000 g / mol.

[0105] Embodiment 5. The cross - linked polyacrylate of any of the foregoing numbered embodiments, wherein substantially no polar structural moieties are present in the polyolefin cross - linker.

[0106] Embodiment 6. The cross - linked polyacrylate of any of the foregoing numbered embodiments, wherein the polyolefin cross - linker comprises polybutadiene or polyfarnesene.

[0107] Embodiment 7. The cross - linked polyacrylate of any of the foregoing numbered embodiments, wherein the polybutadiene or polyfarnesene is hydrogenated.

[0108] Embodiment 8. The cross - linked polyacrylate of any of the foregoing numbered embodiments, wherein the polyacrylate has a PDI of 2.4 or less.

[0109] Embodiment 9. The crosslinked polyacrylate of any of the preceding numbered embodiments, which has an Mn of at least 20,000 g / mol.

[0110] Embodiment 10. The crosslinked polyacrylate of any of the preceding numbered embodiments, which has an Mw of at least 50,000 g / mol.

[0111] Embodiment 11. The crosslinked polyacrylate of any of the preceding numbered embodiments, which has an Mz of at least 50,000 g / mol.

[0112] Embodiment 12. The crosslinked polyacrylate of any of the preceding numbered embodiments, which has a PDI in the range of 2.5 to 20.

[0113] Embodiment 13. The crosslinked polyacrylate of any of the preceding numbered embodiments, wherein the one or more monofunctional acrylate monomer-derived units are selected from the free radical structures within the polymer chain represented by the following formula: wherein R' is hydrogen or methyl, and R is hydrogen or a linear, branched or cyclic hydrocarbon group, and n is an integer from 10 to 10,000.

[0114] Embodiment 14. The crosslinked polyacrylate of any of the preceding numbered embodiments, wherein the one or more monofunctional acrylate monomer-derived units are selected from the free radicals of lauryl acrylate, n-butyl acrylate, benzyl acrylate, acrylic acid, lauryl methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, polybutadiene methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate, and poly(ethylene glycol) methacrylate and combinations thereof.

[0115] Embodiment 15. The crosslinked polyacrylate of any of the preceding numbered embodiments, which comprises a reaction product of one or more monofunctional acrylate monomers; and one or more polyolefin crosslinking agents having at least two reactive dienes and an Mn value of greater than 1000 g / mol; wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol.

[0116] Embodiment 16. The crosslinked polyacrylate of Embodiment 15, wherein the polyolefin crosslinking agent comprises a polyolefin homopolymer or copolymer having at least two reactive dienes and is formed from olefin monomers selected from C2 to C50 olefins, wherein the homopolymer or copolymer is linear or branched, and wherein the branching can be a C1 to C50 hydrocarbon branch.

[0117] Embodiment 17. A crosslinked polyacrylate numbered according to Embodiment 15 or 16, wherein the polyolefin crosslinking agent is selected from the following structures: and combinations thereof, where n and m are integers in the range of 1 to 10, or 20, or 40, and where any one or more of the hydroxyl groups in the structure may be esterified to form acrylate analogs, and where R is a hydrocarbon group and R' is hydrogen or methyl.

[0118] Embodiment 18. A crosslinked polyacrylate numbered according to any one of Embodiments 15 to 17, wherein the one or more monofunctional acrylic monomers are selected from the structures represented by the formula CH2=CR—C(O)X—R', where R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", R' is hydrogen or a linear, branched or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched or cyclic hydrocarbon group.

[0119] Embodiment 19. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, which comprises combining one or more monofunctional acrylic monomers with a polyolefin crosslinking agent having at least two reactive dienes, wherein: (a) the polyolefin crosslinking agent is combined over time; (b) both are combined simultaneously; (c) the monofunctional acrylic monomer is combined over time, or (d) the monofunctional acrylic monomer and the polyolefin crosslinking agent are combined with each other over time.

[0120] Embodiment 20. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, wherein the combining is carried out at a temperature of 90 °C or higher.

[0121] Embodiment 21. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, wherein the combining is carried out at a temperature of less than 90 °C.

[0122] Embodiment 22. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, wherein the combining is carried out at a temperature in the range of 88 to 95 °C.

[0123] Embodiment 23. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, wherein the combining is carried out at a temperature in the range of 65 to 88 °C.

[0124] Embodiment 24. A method of forming a crosslinked polyacrylate according to any one of the preceding numbered embodiments, wherein the monomer and the crosslinking agent are continuously added over a time in the range of 10 to 300 minutes.

[0125] Embodiment 25. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, wherein the monomer and the crosslinking agent are added in time portions over a period of 10 to 300 minutes.

[0126] Embodiment 26. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, further comprising combining an initiator, wherein the initiator is combined with the monomer and the crosslinking agent over time.

[0127] Embodiment 27. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, further comprising combining an initiator, wherein the initiator is combined with the monomer and the crosslinking agent simultaneously.

[0128] Embodiment 28. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, further comprising combining an initiator, wherein the combining is carried out at a temperature such that the half-life of the initiator is in the range of 1 to 10 hours.

[0129] Embodiment 29. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, wherein the polyolefinic crosslinking agent is combined in an amount of 0.1 to 20% by weight of the polyolefinic crosslinking agent and one or more monofunctional acrylic monomers.

[0130] Embodiment 30. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, wherein each polyacrylate comprises one or more monofunctional acrylic monomers to form at least two polymer chains bonded to each other by at least one polyolefinic crosslinking agent having at least two reactive dienes, wherein the polyolefinic crosslinking agent has an Mn value greater than 1000 g / mol; and wherein the crosslinked polyacrylate has an Mw of at least 30,000 g / mol.

[0131] Embodiment 31. A method for forming a crosslinked polyacrylate of any of the foregoing numbered embodiments, wherein there are no additional steps for curing or effecting crosslinking.

[0132] The following non-limiting examples are provided to illustrate the present disclosure. Examples

[0133] All reactions were carried out in a 4-neck reaction vessel equipped with an overhead stirrer, a temperature probe, a nitrogen inlet (for sparging), a Friedrich condenser, and a addition funnel. The solvent, chain transfer agent (CTA) (optional), and those monomers and / or crosslinkers to be added "up front" were loaded into the reactor at the target weights and sparged with nitrogen for 15 - 30 minutes at room temperature. "Up front" means loading the reagent into the reaction at the beginning, time = 0; if two or more reagents are loaded up front or "combined", they are "simultaneously" combined at time = 0. In a separate container, the CTA (optional), initiator, and solvent were added at the target weights and sparged with nitrogen for 15 minutes. In order to react with the crosslinker and / or monomer added over time, these were also weighed into a separate container up to the target mass and sparged for 15 - 30 minutes. "Over time" addition means that the corresponding reagent is added slowly over time, e.g., over 30, 60, or 240 minutes or other specified time periods. The reaction flask was heated to the target reaction temperature. For "up front" initiator addition, the initiator, solvent, and optional CTA mixture were added to the reaction to start the reaction. The reaction temperature was maintained at the target temperature as shown in Table 1. For reagents added over time, the reagents were fed in using the addition funnel over the specified time as shown in Table 1. After the reaction time ended, the sample was cooled to ambient temperature. To recover the solid polymer, the sample was poured into a PTFE dish and dried under vacuum until the residual solvent was no longer visibly evident in the FTIR. The reaction temperature, the identity and amount of the initiator, and the solvent mixture were adjusted to prevent gelling and obtain the desired crosslinked polyacrylate based on the choice of monomer and crosslinker. Table 1. Process Conditions

[0134] The starting reagents for making the crosslinked polyacrylates of the comparative examples and the examples of the present invention and some of their characteristics are shown in Tables 2A, 2B, and 2C. "Molecular weight" is a simple calculated value based on atomic structure. The crosslinking agents disclosed in Tables 2B and 3 and used in the examples of the present invention are made using anionic polymerization methods and have a PDI of less than 2. In some cases, the starting crosslinking agent material is esterified to form the corresponding acrylate material with a crosslinkable diene. To perform this operation, a 4-neck reaction vessel is equipped with an overhead stirrer, a temperature probe, a nitrogen inlet (for bubbling), a condenser, and a Dean Stark trap. The alcohol-containing reagent (see Table 3) and methyl methacrylate are added to the reaction flask, with an excess of methyl methacrylate. The mixture is stirred at 60 °C for 30 minutes to ensure heterogeneity. 4-Methoxyphenol is added, followed by 4-hydroxy-2,2,6,6,-tetramethylpiperidine-1-oxy. The mixture is heated to the reflux temperature of 100 °C under a nitrogen blanket, and approximately 20 grams of methyl methacrylate are distilled off. The mixture is cooled to 85 °C and methyllithium is added. The mixture is heated to 105 °C and methanol and methyl methacrylate are removed. After the start of methyl methacrylate distillation, the reaction is maintained at 105 °C for 4 to 6 hours. The reaction is cooled to 70 °C and filtered through Celite 535. Residual methyl methacrylate is removed by rotary evaporation at 90 - 125 °C until it is no longer visible by 1H NMR. Table 2A. Monomers Table 2B. Crosslinking Agents Table 2C. Other Reagents

[0135] Notes on Tables 2A, B, and C are as follows: A - See Esterification Table 3 and the above esterification method; B - Unless noted, values are taken from online sources, literature, commercial manuals, and from Physical Properties of Polymers Handbook, 2nd Edition, 2007, Springer; C - Unless noted, values are taken from online sources, literature, and from Physical Properties of Polymers Handbook, 2nd Edition, 2007, Springer; D - Values are for hydrogenated poly(butadiene); E - Estimated by comparison with other similar structures; F - Values are for amorphous poly(ethylene glycol); and G - Values are based on hexyl methacrylate.

[0136] Table 2D gives further information on the initiators used, where chlorobenzene was obtained from Nouryon. Table 2D. Calculated initiator half-lives in chlorobenzene based on the Arrhenius Equation and Constant Table 3. Esterification reagents Precursor Name Starting Material Source Molecular Weight (Mn) (g / mol) KMA <![CDATA[Krasol TM HLBH 5000M]]> Total Cray Valley 5000 P3000 <![CDATA[Krasol TM HLBH P3000]]> Total Cray Valley 3000 P2000 <![CDATA[Krasol TM HLBH P2000]]> Total Cray Valley 2000

[0137] The following tables, Tables 4 to 14 (“Table A” summarizes the reaction conditions and reagents used, while “Table B” summarizes the characterization of the materials obtained) summarize the comparative polyacrylates and small crosslinker polyacrylates (C1, C2, etc.) and the crosslinked polyacrylates of the present invention (E1, E2, etc.). The examples are generally sorted by the process conditions characterized in Table 1 above. These examples were characterized by various methods.

[0138] The following was used for polystyrene standards (Acquity TM APC Polystyrene High MW Calibration Kit (Acquity TMAPC Polystyrene High MW Calibration Kit), 266 to 4,000,000 Da) The moments of molecular weight (Mn, Mw, Mz) are determined by gel permeation chromatography (GPC-PS). The molecular weights (number average molecular weight (Mn), weight average molecular weight (Mw), and z-average molecular weight (Mz)) are determined using an Agilent Acuity P-SM-FTN and P-15m high-temperature GPC-SEC (gel permeation / size exclusion chromatograph) equipped with an on-line differential refractive index (DRI) detector and a PDA UV detector for wavelengths 215, 254, and 304. GPC uses 3 Agilent PLgel 10 micron Mixed B LS columns. Column separation is carried out with a flow rate of 1 mL / min and a nominal injection volume of 10 microliters. When in the low flow mode (idle), the detector and columns are maintained at 30 °C and heated to 35 °C when preparing to run a sample. The stream leaving the SEC column is directed into an optical flow cell and then into the DRI detector. The solvent used for SEC experiments is suppressed THF (tetrahydrofuran). Polymer solutions are prepared by placing the dried polymer in a glass container and adding the required amount of THF. Once the sample is added to the machine, a certain amount of time is allowed to elapse before the run begins to reach 35 °C. The GPC run is programmed for a pre-run equilibration of approximately 1.5 hours. Depending on solubility, the sample is stirred for 2 to 15 hours. The sample is filtered after stirring and before running. All amounts are measured by gravimetric analysis. The density of THF used to express the polymer concentration in mass / volume units is 0.887 g / mL at 68 °C. The injected sample concentration is 1 to 3 mg / mL. Before running each sample, the DRI detector and syringe are purged. Then the flow rate in the device is increased from 0.01 to 0.25 mL / min and the DRI is allowed to stabilize for 4 to 5 hours before injecting the first sample. The software used to run GPC and prepare reports is Empower TM 3, version 7.41.00.00.

[0139] Proton nuclear magnetic resonance (1H-NMR) is carried out as follows. Samples are run on a Bruker 300 MHz NMR instrument. Samples are loaded into NMR tubes in deuterated chloroform at a 50 / 50 ratio. Scans (128) are carried out and the spectra are analyzed in iNMR software. The conversion of (meth)acrylate is calculated by normalizing the ratio of ester protons to residual unsaturation.

[0140] Rheological properties, such as G" and tan(δ), were measured as follows: A dry polymer sample was loaded onto a TA ARES G2 rheometer equipped with 25 mm stainless steel parallel plates, a forced convection oven, and an active cooling system. For all samples, the loading gap was approximately 1 mm, and care was taken to remove air bubbles during loading. G' and G” were measured as a function of temperature and frequency under small amplitude oscillatory shear in the linear viscoelastic regime. Frequency sweep measurements were performed at multiple temperatures to enable time-temperature superposition of the data. The target measurement temperatures were selected based on the physical properties and feasibility of each material. Typically, a reference temperature of 25 °C was used for low Tg materials and 110 °C for high Tg materials in the time-temperature superposition analysis. The Williams-Landel-Ferry model was used for time-temperature superposition. Although incorporating multiple monomers with different friction factors, this superposition always successfully represented the data (for representative results on displacement, see Figure 1 ). No vertical displacement was performed. Horizontal shift factors aT were provided as a function of temperature, e.g., in Figure 2 .

[0141] Certain calculations were performed. The weight average monomer solubility parameter was calculated according to the following equation (3) using the solubility parameters provided in Tables 2A and 2B: Weight average monomer SP = ∑ i w i SP i (3) ← where w i is the weight fraction of monomer i, and SP i is the solubility parameter of monomer i.

[0142] The Flory-Fox monomer glass transition temperature was calculated according to the following Flory Fox equation (4) using the glass transition temperatures provided in Tables 2A and 2B, excluding the contribution from crosslinkers: where wi is the weight fraction of monomer i, and Tg,i is the glass transition temperature of monomer i.

[0143] The Flory-Fox polymer glass transition temperature is calculated according to the Flory Fox equation above using the provided glass transition temperature, including the contribution from the crosslinker. After time-temperature superposition, the values of G” and tan(δ) are reported at each temperature and frequency. The temperature in each case is the reference temperature for superposition, and the values of G” and tan(δ) as a function of frequency are taken directly from the master curve. The zero-shear viscosity and the crossover exponent are determined by fitting the master complex viscosity to the crossover model in equation (5): where η* is the complex viscosity, η0 is the zero-shear viscosity, τ0 is the characteristic time, and "a" is the crossover exponent.

[0144] The polymer flow temperature is the temperature at which, upon heating, tan(δ) ≥ 5 at an angular frequency of 1 rad / s and above which tan(δ) increases monotonically. It is determined from the master curve after time-temperature superposition of the frequency data captured by rheology as described above.

[0145] In the table, “NM” means “not measured”. Table 4A. Reagents and reaction conditions for Examples 1-7 Table 4B. Characterization of polymer products of Examples 1-7 Table 5A. Reagents and reaction conditions for Examples 8-12, Comparative 1 and 2 Table 5B. Characterization of polymer products of Examples 8-12, Comparative 1 and 2 Table 6A. Reagents and reaction conditions for Examples 13-17, Comparative 3 and 4 Table 6B. Characterization of polymer products of Examples 13-17, Comparative 3 and 4 Table 7A. Reagents and reaction conditions for Examples 18-23, Comparative 5 Table 7B. Characterization of polymer products of Examples 18-23, Comparative 5 Table 8A. Reagents and reaction conditions for Examples 24-30 Table 8B. Characterization of Polymer Products for Examples 24 - 30 Table 9A. Reagents and Reaction Conditions for Examples 31 - 37 Table 9B. Characterization of Polymer Products for Examples 31 - 37 Table 10A. Reagents and Reaction Conditions for Examples 38 - 44 Table 10B. Characterization of Polymer Products for Examples 38 - 44 Table 11A. Reagents and Reaction Conditions for Examples 45 - 50, Comparative 6 Table 11B. Characterization of Polymer Products for Examples 45 - 50, Comparative 6 Table 12A. Reagents and Reaction Conditions for Examples 51 - 57 Table 12B. Characterization of Polymer Products for Examples 51 - 57 Table 13A. Reagents and Reaction Conditions for Examples 58 - 62, Comparative 7 and 8 Table 13B. Characterization of Polymer Products for Examples 58 - 62, Comparative 7 and 8 Table 14A. Reagents and Reaction Conditions for Examples 63 - 68 Table 14B. Characterization of Polymer Products for Examples 63 - 68

[0146] Data demonstrate the shear thinning effect by using the polyolefin crosslinker of the present invention. This effect is at least partly attributed to a significant increase in the molecular weight of the crosslinked polyacrylate made using the polymeric crosslinker while keeping all other conditions constant. Note that 1,6-hexyl crosslinked polyacrylate also has a directionally higher z-average molecular weight (Mz) than the polymer without the crosslinker, but the shear thinning behavior still tends to be higher than that of the crosslinked polyacrylate of the present invention with a similar molecular weight (Mz), which is unexpected. See, for example Figure 3 and Figure 4 for the comparison, which shows the bulk shear thinning properties (cross-over exponents) at equal molar ratios and using only LMA as the monofunctional acrylic monomer ( Figure 3 ) and a consistent composition of the monofunctional acrylic monomer ( Figure 4 ). In these two figures, the numbers on each bar are the measured molecular weights (Mz) in kDa.

[0147] The data in the table further demonstrate the surprising effect of the selection of the monofunctional acrylic monomer. It was expected that a higher molecular weight would enhance shear thinning (reduce the cross-over exponent). However, Figure 5 demonstrates that for examples using the same crosslinker type and amount, when different monofunctional acrylic monomers are used (Mz values are shown above each bar), the effect of the molecular weight on the cross-over exponent is not obvious.

[0148] The crosslinked polyacrylates described herein can be used in many applications, such as for adhesives, flow improvers, coatings, and adhesives, to improve, for example, the processing properties and the properties of the final product.

[0149] All documents described herein are hereby incorporated by reference to the extent that they are not inconsistent with the present application, including any priority documents and / or test procedures. From the above general description and specific embodiments, it is apparent that although the forms of the present invention have been illustrated and described, various modifications can be made without departing from the spirit and scope of the present invention. Accordingly, it is not intended to limit the present invention thereby.

[0150] The term "comprising" is considered synonymous with the term "including". Similarly, as long as a composition, element, or group of elements is preceded by the conjunction "comprising", it is understood that we also contemplate the same composition or group of elements preceded by the conjunctions "consisting essentially of", "consisting of", "selected from", or "being", and vice versa.

Claims

1. A cross-linked polyacrylate comprising the reaction product of: one or more monofunctional acrylic monomers; and one or more polyolefinic crosslinking agents having at least two reactive dienes and an Mn value greater than 1000 g / mol; wherein the cross-linked polyacrylate has an Mw of at least 30,000 g / mol.

2. The cross-linked polyacrylate of claim 1, wherein the polyolefinic cross-linking agent has a PDI of 2.2 or less, and an Mn value in the range of 1000 to 6000 g / mol, and wherein substantially no polar moieties are present in the polyolefinic cross-linking agent.

3. The crosslinked polyacrylate according to claims 1-2, wherein the polyolefinic crosslinking agent is a polybutadiene or polyfarnesene having at least two reactive dienes.

4. The cross-linked polyacrylate according to claim 1-2, wherein the polyolefin cross-linking agent is selected from the following structures: and combinations thereof, wherein n and m are integers in the range of 0 to 40, wherein n+m≥1, and wherein any one or more hydroxyl groups in the structure can be esterified to form an acrylate analog, and wherein R is a hydrocarbon group and R' is hydrogen or methyl.

5. The cross-linked polyacrylate of claims 1-4 having a Mw of at least 50,000 g / mol and having a Mz of at least 50,000 g / mol.

6. The cross-linked polyacrylate according to claims 1-5, wherein the one or more monofunctional acrylic monomers are selected from the structure represented by the formula CH2=CR—C(O)X—R', wherein R is hydrogen or methyl, X is independently oxygen or a group of the formula NR", R' is hydrogen or a linear, branched or cyclic hydrocarbon group, and R" is hydrogen or a linear, branched or cyclic hydrocarbon group.

7. The cross-linked polyacrylate of claims 1-6, wherein the one or more monofunctional acrylic monomers are selected from the group consisting of lauryl acrylate, n-butyl acrylate, benzyl acrylate, acrylic acid, lauryl methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, polybutadiene methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate and poly(ethylene glycol) methacrylate, and combinations thereof.

8. A cross-linked polyacrylate comprising at least two polyacrylates comprising one or more monofunctional acrylic monomer-derived units, the at least two polyacrylates being bonded to each other via at least one polyolefinic cross-linking agent, wherein the at least one polyolefinic cross-linking agent has an Mn value greater than 1000 g / mol, and wherein the cross-linked polyacrylate has an Mw of at least 30,000 g / mol.

9. The cross-linked polyacrylate of claim 8, wherein the polyolefinic cross-linking agent has a PDI of 2.2 or less, and an Mn value in the range of 1000 to 6000 g / mol, and wherein substantially no polar moieties are present in the polyolefinic cross-linking agent.

10. The cross-linked polyacrylate according to claims 8-9, wherein the polyolefinic cross-linking agent is selected from the following structures: and combinations thereof, wherein n and m are integers in the range of 0 to 40, wherein n+m≥1, and wherein any one or more hydroxyl groups in the structure can be esterified to form an acrylate analog, and wherein R is a hydrocarbon group and R' is hydrogen or methyl.

11. The cross-linked polyacrylate according to claims 8-9, wherein the polyolefinic cross-linking agent comprises a polyolefin homopolymer or copolymer having at least two reactive dienes and is formed from olefin monomers selected from C2 to C50 olefins, wherein the homopolymer or copolymer is linear or branched, and wherein the branches may be C1 to C50 hydrocarbon branches.

12. The cross-linked polyacrylate according to claims 8-11, wherein the one or more monofunctional acrylic monomer derived units are selected from the free radical structures shown in the following formula: wherein R' is hydrogen or methyl, and R is hydrogen or a linear, branched or cyclic hydrocarbon group, and n is an integer from 10 to 10,000.

13. The cross-linked polyacrylate of claims 8-12, wherein the one or more monofunctional acrylic monomer derived units are selected from the free radicals of lauryl acrylate, n-butyl acrylate, benzyl acrylate, acrylic acid, lauryl methacrylate, hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, methacrylic acid, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, polybutadiene methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate and poly(ethylene glycol) methacrylate and combinations thereof.

14. A method of forming a cross-linked polyacrylate having a Mw of at least 30,000 g / mol comprising combining one or more monofunctional acrylic monomers with a polyolefinic cross-linker having at least two reactive dienes, wherein: (a) the polyolefinic crosslinking agent is incorporated over time; (b) both are merged simultaneously; (c) the monofunctional acrylic monomers are combined over time, or (d) The monofunctional acrylic monomer and the polyolefinic crosslinking agent are combined with each other over time.

15. The method of claim 14, wherein the combining is performed at a temperature in the range of 65 to 95°C.

16. The method according to claims 14-15, wherein the monomer or cross-linking agent is added continuously or in portions over a time in the range of 10 to 300 minutes.

17. The method of claims 14-16, further comprising combining an initiator, wherein the initiator is combined with the monofunctional acrylic monomer and the polyolefinic crosslinker over time or simultaneously with the monofunctional acrylic monomer and the polyolefinic crosslinker.

18. The method of claims 14-17, further comprising combining an initiator, wherein the combining is performed at a temperature such that the half-life of the initiator is in the range of 1 to 10 hours.

19. The method of claims 14-18, wherein the polyolefinic crosslinking agent is combined in an amount of 0.1 to 20 weight percent based on the weight of the polyolefinic crosslinking agent and the one or more monofunctional acrylic monomers.

20. The method of claims 14-19, wherein there is no additional step of curing or effecting cross-linking.

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