Method of producing glycerol carbonate (METH)acrylate, and curable compositions based on glycerol carbonate (METH)acrylate

Abstract

To provide a method for producing glycerol carbonate (meth)acrylate, and curable compositions containing glycerol carbonate (meth)acrylate.SOLUTION: Glycerol carbonate methacrylate may be produced by reacting glycerol monomethacrylate with a carbonate such as a dialkyl carbonate in the presence of a catalyst, and may be combined with an actinic radiation-curable oligomer, such as a (meth)acrylate-functionalized oligomer, and optionally other components to provide compositions capable of being cured, e.g., by exposure to actinic radiation, to obtain polymeric materials, such as 3D printed articles. The glycerol carbonate methacrylate reduces the viscosity of the composition, which may in the absence of the glycerol carbonate methacrylate be too high for the curable composition to be readily processed at room temperature, but additionally can impart a variety of other useful attributes to the curable compositions and cured products derived therefrom.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a process for producing glycerol carbonate (meth)acrylates and to curable compositions containing glycerol carbonate (meth)acrylates. [Background technology]

[0002] Glycerol carbonate methacrylate (i.e., the methacrylic acid ester of glycerol carbonate, also known as glycerin carbonate methacrylate) has the following structure:

[0003] [ka]

[0004] It has been identified as a useful synthetic intermediate and monomer having the formula:

[0005] For example, JP 2011-219394 A teaches that (meth)acrylic acid esters having a 2-oxo-1,3-dioxolane (cyclic carbonate) structure, such as glycerol carbonate methacrylate, can be used as raw materials for paints, functional polymers, medicines, agricultural chemicals, and other fine chemicals.

[0006] Various synthetic routes to glycerol carbonate methacrylate have been described in the literature, but the most interesting method involves the reaction of glycidyl methacrylate with carbon dioxide in the presence of a suitable catalyst. Such chemical reactions are described, for example, in US Pat. No. 4,835,289 and JP 2014-051456. Although glycerol carbonate methacrylate can be obtained in high yield using such methods, one drawback of this synthetic route is that glycidyl methacrylate must be utilized as the starting material. Glycidyl methacrylate is generally commercially prepared by reacting epichlorohydrin with methacrylic acid. The resulting reaction product is typically contaminated with unreacted epichlorohydrin, which is recognized as being corrosive and posing significant health and safety concerns. If not removed, residual epichlorohydrin in glycerol carbonate methacrylate may hinder the ability to formulate glycerol carbonate methacrylate into various compositions, such as coatings, inks, 3D printed articles, etc., that may come into contact with human skin or other biological tissues. Furthermore, the presence of residual epichlorohydrin may affect the regulatory classification of such compositions and products. Therefore, it would be of great interest to develop a viable alternative method for synthesizing glycerol carbonate methacrylate that does not involve the use of starting materials containing epichlorohydrin.

[0007] Curable compositions containing glycerol carbonate methacrylate as a component have not received much attention to date. Camara et al., European Polymer Journal 61 (2014) 133-144, report what is said to be the first complete study of the free radical polymerization of glycerol carbonate methacrylate to synthesize cyclic carbonate functionalized polymers, including copolymers with methyl methacrylate and other acrylic, methacrylic and styrenic monomers. Example 9 of US Patent Application Publication No. 2017 / 0260418 A1 describes an ink containing glycerol carbonate methacrylate, triethylene glycol dimethacrylate and a photoinitiator, used as part A of a two-component ink for 3D printing. However, according to the published patent application, such an ink must be combined with an ink containing an amine monomer ("part B"), in which the amine monomer contains one or more primary, secondary and / or tertiary amine groups, to be suitable for use in 3D printing.

[0008] EP0001088A1 discloses polymers containing 1,3-dioxalan-2-one groups in the side chain, obtained by polymerization of corresponding unsaturated compounds such as glycerol carbonate methacrylate. Copolymerization with other olefinically unsaturated monomers is also described. The polymers can be used to produce moldings or molding compounds, coatings, adhesives and papermaking and textile auxiliaries. There is no mention of achieving such polymerization by photocuring, nor does the publication disclose the copolymerization of carbonate-containing monomers such as glycerol carbonate methacrylate with olefinically unsaturated oligomers.

[0009] US Patent No. 5,047,261 discloses a method for preparing coatings by radiation crosslinking a radiation crosslinkable composition having a reactive diluent system containing at least one mono(meth)acrylic carbonate corresponding to a specific formula: Although glycerol carbonate acrylate is used as a monomer in Comparative Examples 9 and 21, the patent does not disclose a radiation crosslinkable composition containing glycerol carbonate methacrylate.

[0010] It is generally recognized that methacrylate compounds (i.e., compounds containing one or more methacrylate functional groups, -OC(=O)C(CH3)=CH2) react and cure much slower when exposed to actinic radiation than similar acrylate compounds (i.e., compounds containing one or more acrylate functional groups, -OC(=O)CH=CH2). [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent Publication No. 2011-219394 [Patent Document 2] U.S. Patent No. 4,835,289 [Patent Document 3] Patent Publication No. 2014-051456 [Patent Document 4] US Patent Application Publication No. 2017 / 0260418A1 [Patent Document 5] EP0001088A1 [Patent Document 6] U.S. Patent No. 5,047,261 [Patent Document 7] U.S. Patent No. 7,342,054B2 [Patent Document 8] WO00 / 63149 [Patent Document 9] WO00 / 63150 [Patent Document 10] WO2017 / 125759 [Patent Document 11] WO2014 / 126830 [Patent Document 12] WO2014 / 126834 [Patent Document 13] WO2014 / 126837 [Non-patent literature]

[0012] [Non-Patent Document 1] Camara et al., European Polymer Journal 61 (2014) 133~144 [Non-Patent Document 2] "Continuous Liquid Interface Production of 3D Objects", Science Vol. 347, No. 6228, pp. 1349-1352 (March 20, 2015) Summary of the Invention [Means for solving the problem]

[0013] The inventors have now discovered that glycerol carbonate methacrylate can be easily prepared in high yield by reacting glycerol monomethacrylate with a carbonate selected from the group consisting of dialkyl carbonates and cyclic alkylene carbonates in the presence of a catalyst. Surprisingly, the methacrylate functional group substantially survives the reaction in which the cyclic carbonate group is formed by exchange of the carbonate reactant with the hydroxyl group of glycerol monomethacrylate. An alcohol co-product is produced along with the glycerol carbonate methacrylate, but can be easily separated by distillation or other such means. The conversion of the starting glycerol monomethacrylate to the desired glycerol carbonate methacrylate can be accomplished by the following:

[0014] [ka]

[0015] It can be represented diagrammatically as follows:

[0016] Other types of co-reactants may be used in place of carbonates, especially those that can function as synthetic equivalents of dialkyl carbonates or cyclic alkylene carbonates. Such alternative co-reactants include compounds containing a carbonyl group in which the carbon atom of the carbonyl group is substituted with two groups that can be substantially replaced by the hydroxyl group of glycerol monomethacrylate. Such substituents may be, for example, aroxy (e.g., phenoxy), alkoxy (including halogenated alkoxy such as Cl3CO-), halo (e.g., Cl, Br), alkylthio or amino groups. Suitable alternative co-reactants include, for example, compounds corresponding to the general formula XC(=O)Y, where X and Y may be the same or different from each other and are selected from the group consisting of aroxy, alkoxy, halo, alkylthio (e.g., RS-, where R is an alkyl group) and amino (-NH2, -NHR and -NR2, where R is an organic group and the nitrogen atom may be part of a ring structure such as in an imidazole or benzotriazole group). X and Y may be linked together to form a cyclic structure. Examples of suitable non-carbonate co-reactants include, but are not limited to, phosgene, triphosgene, urea, carbonyldiimidazole, carbonyldibenzotriazole, dimethyldithiocarbonate, phenyl chloroformate, trihaloacetyl chloride, and nitrophenyl benzylcarbamate.

[0017] The starting material glycerol monomethacrylate (also known as 2,3-dihydroxypropyl methacrylate) may be prepared by any known method, such as monoesterification of glycerol with a methacrylate source such as methacrylic acid, methacrylic anhydride, methacryloyl chloride or a lower alkyl ester of methacrylic acid, or hydrolysis of the epoxy group in glycidyl methacrylate. Other methods are described, for example, in U.S. Pat. No. 7,342,054 B2, WO00 / 63149, and WO00 / 63150. One advantage of the method of the present invention for preparing glycerol carbonate methacrylate is that the starting material glycerol monomethacrylate is not prepared using epichlorohydrin. For example, an epichlorohydrin-free grade of glycidyl methacrylate may be used as a precursor to glycerol monomethacrylate. Thus, in contrast to known synthetic routes that utilize glycidyl methacrylate as a starting material, the preparation of epichlorohydrin-free glycerol carbonate methacrylate is feasible.

[0018] Furthermore, the inventors have established that glycerol carbonate methacrylate in combination with one or more actinically curable oligomers (particularly one or more (meth)acrylate-functionalized oligomers) can be used in addition to glycerol carbonate methacrylate, and optionally with one or more other ingredients such as photoinitiators and / or actinically curable monomers (e.g., (meth)acrylate-functionalized monomers), to formulate compositions that can be readily cured upon exposure to actinic radiation to form useful polymeric products. Glycerol carbonate methacrylate is particularly well suited for use in such applications due to its properties. Glycerol carbonate methacrylate has a low viscosity at room temperature (55-65 cps at 25° C.) and therefore can function as a reactive diluent, effectively reducing the viscosity of curable compositions containing a high percentage of actinically curable oligomers. When homopolymerized, glycerol carbonate methacrylate results in homopolymers with high glass transition temperature (>160°C), high tensile strength (>18MPa) and high tensile modulus (80MPa). Thus, the incorporation of glycerol carbonate methacrylate into actinically curable oligomer-containing curable compositions serves to significantly improve the physical and mechanical properties of the cured polymer matrix obtained therefrom. Furthermore, glycerol carbonate methacrylate does not have acute toxicity, in contrast to other (meth)acrylate-functionalized compounds that can also be used as reactive diluents. Thus, medical devices and products suitable for use in medical applications where the products are in contact with human subjects can be prepared from the curable compositions according to the present invention.

[0019] Furthermore, glycerol carbonate methacrylate exhibits polymerization kinetics that are atypical for methacrylate-functionalized compounds. Acrylates and methacrylates generally have different reactivities when polymerized using actinic radiation, with methacrylates curing significantly slower than the corresponding acrylates. As will be explained in more detail below, the inventors have discovered that glycerol carbonate methacrylate can be used in methacrylate-based formulations to increase radiation cure speed and flexural strength (green strength). [Brief description of the drawings]

[0020] [Figure 1] 1 is a graph showing various experimental data described in the examples. [Diagram 2] 1 is a graph showing various experimental data described in the examples. [Diagram 3] 1 is a graph showing various experimental data described in the examples. [Figure 4] 1 is a graph showing various experimental data described in the examples. [Diagram 5] 1 is a graph showing various experimental data described in the examples. [Figure 6] 1 is a graph showing various experimental data described in the examples. [Figure 7] 1 is a graph showing various experimental data described in the examples. [Figure 8] 1 is a graph showing various experimental data described in the examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Synthesis of glycerol carbonate methacrylate from glycerol monomethacrylate and carbonate. Suitable carbonates for reacting with glycerol monomethacrylate include carbonates selected from the group consisting of dialkyl carbonates and cyclic alkylene carbonates. Although mixtures of such carbonates may be used, in certain embodiments, only a single carbonate coreactant is utilized. Suitable dialkyl carbonates include, in particular, carbonates in which the alkyl group is a lower alkyl group, e.g., a C1-C6 alkyl group, which may be linear or branched. For example, the alkyl group may be methyl, ethyl, propyl (including n-propyl and isopropyl), and butyl (including n-butyl, sec-butyl, and tert-butyl). Suitable cyclic alkylene carbonates include, by way of example, ethylene carbonate and propylene carbonate. According to certain desirable embodiments of the invention, the carbonate is selected such that the resulting alcohol co-product has a boiling point at atmospheric pressure of 200° C. or less, 175° C. or less, 150° C. or less, 125° C. or less, or 100° C. or less to facilitate separation of the co-product alcohol formed either during or after the reaction of glycerol monomethacrylate with the carbonate.

[0022] Any suitable molar ratio of carbonate to glycerol monomethacrylate that favors the formation of glycerol carbonate methacrylate may be used in the reaction. However, at least a stoichiometric level of carbonate to glycerol monomethacrylate is typically used, with a moderate molar excess of carbonate generally being preferred. Preferably, the molar ratio of carbonate to glycerol monomethacrylate ranges from 1:1 to 3:1. For example, in one embodiment, the molar ratio of carbonate:glycerol monomethacrylate is 1.1:1 to 1.2:1.

[0023] Suitable catalysts include any material capable of accelerating the reaction rate between glycerol monomethacrylate and carbonate, generally including Lewis acids, Lewis bases, Bronsted bases, and basic catalysts (Lewis or Bronsted). The catalyst may be homogeneous (dissolved in the reaction mixture under reaction conditions) or heterogeneous (not dissolved in the reaction mixture under reaction conditions). The catalyst may also be partially dissolved under reaction conditions. A mixture of two or more different catalysts may be used.

[0024] Suitable basic catalysts include, without limitation, alkali metal (e.g., Li, Na, K) and alkaline earth metal (e.g., Ca, Mg) compounds of organic (i.e., containing one or more organic moieties in addition to alkali metal and / or alkaline earth metal) or inorganic nature. Such compounds may be, for example, hydroxides, alkoxides, carbonates, bicarbonates, silicates, aluminates, oxides, etc. Basic ion exchange resins or basic zeolites may also be utilized. According to certain embodiments of the present invention, the catalyst is a strong base, i.e., having a pK of up to 5. b It is a base having a value.

[0025] Suitable catalysts include basic catalysts selected from alkali metal carbonates, alkali metal bicarbonates, alkali metal hydroxides, alkali metal oxides, alkali metal alkoxides, alkali metal aluminates, alkali metal silicates, alkaline earth metal carbonates, alkaline earth metal bicarbonates, alkaline earth metal hydroxides, alkaline earth metal oxides, alkaline earth metal alkoxides, alkaline earth metal aluminates, alkaline earth metal silicates, and combinations thereof. In a preferred embodiment, the catalyst is an alkali metal hydroxide or an alkali metal alkoxide. References herein to "alkoxide" include C1-C6 linear or branched alkoxides, such as C1-C2 alkoxides. Specific examples of suitable catalysts include NaOH, KOH, NaOMe, NaOEt, KOMe, KOEt, Na2CO3, NaHCO3, K2CO3, KHCO3, and Na2SiO3. Amine compounds, including tertiary amines, can also be utilized as suitable catalysts. Also suitable for use as catalysts are materials known as "ionic liquids", such as those described in WO2017 / 125759 (incorporated herein by reference in its entirety for all purposes). Exemplary ionic liquids for this purpose include ionic liquids containing ammonium or phosphonium cations, or aromatic heterocyclic cationic species. The catalyst may be combined with the reactants in dry or neat form, but in certain embodiments may be provided in the form of a solution or slurry in combination with a solvent.

[0026] The catalyst is provided to the initially formed reaction mixture in an amount effective to achieve a desired catalytic effect, hi certain embodiments, the catalyst is present in the reaction mixture in an amount of 0.05 to 5% by weight based on the total weight of the initially formed reaction mixture.

[0027] One or more polymerization inhibitors, particularly free radical inhibitors, may be present in the reaction mixture to help reduce undesired reactions of the (meth)acrylate functionality. Suitable polymerization inhibitors include, for example, hydroquinone polymerization inhibitors (e.g., hydroquinone itself and substituted hydroquinones such as hydroquinone monomethyl ether); hindered phenol polymerization inhibitors (e.g., butylated hydroxytoluene); and thiazine polymerization inhibitors (e.g., phenothiazine). The level of polymerization inhibitor in the reaction mixture may vary depending on the type of inhibitor used and other factors, but may typically be from about 5 to about 10,000 ppm.

[0028] Polymerization of the (meth)acrylate-functionalized components of the reaction mixture may also be inhibited by conducting the reaction of glycerol mono(meth)acrylate with carbonate in the presence of molecular oxygen. For example, the reaction mixture may be sparged with a gas comprised of molecular oxygen (e.g., air). The gas supplied to the reaction vessel in which the reaction is taking place may be, for example, atmospheric air, enriched air, or air in which the molecular oxygen content has been reduced from normal (atmospheric) levels to reduce the possibility of flammability.

[0029] One or more solvents may be used in the method of the present invention, but such solvents are not required.Therefore, in one embodiment of the present invention, the reaction between glycerol monomethacrylate and carbonate is carried out in the absence of solvent.For example, the reaction mixture (formed initially) may contain less than 500 ppm or less than 200 ppm of solvent.

[0030] The components of the reaction mixture (glycerol monomethacrylate, carbonate, catalyst, optional solvent, and possibly other optional components) may be charged all at once or sequentially into a suitable reaction vessel. For example, the carbonate may be added in two or more portions to a mixture of the other components of the reaction mixture. The components may be stirred, mechanically mixed, or otherwise agitated during the desired reaction involving the glycerol monomethacrylate and carbonate.

[0031] Glycerol monomethacrylate and carbonate are reacted in the presence of a catalyst at a time, temperature and pressure effective to form the desired glycerol carbonate methacrylate in a targeted yield and selectivity. Generally, the temperature is selected to be a temperature, or range of temperatures, at which the reaction proceeds at a commercially practical rate while avoiding, minimizing or reducing decomposition of the reactants or the formation of undesirable by-products and polymers. Suitable reaction temperatures include, for example, 40°C to 160°C.

[0032] Suitable reaction times may be on the order of a few minutes (eg, at least 10 minutes) up to several hours (eg, up to 12 hours).

[0033] In order to facilitate the desired reaction to form glycerol carbonate monomethacrylate to reach completion or to reach completion sooner, it may be useful to separate the co-product alcohol formed during the reaction from the reaction mixture. As will be understood by those skilled in the art, the term "separate" is intended to refer to the physical extraction of the alcohol co-product from the reaction mixture. As a result, a co-product stream containing alcohol may be obtained. Such separation may be carried out continuously or stepwise. For example, the reaction may be carried out for a predetermined period of time without removing the co-product alcohol, and then the reaction mixture may be subjected to a separation procedure (e.g., flash distillation or column distillation) before continuing to react the components of the reaction mixture in a further reaction step. The recovered alcohol co-product may be recycled (i.e., converted back to carbonate and used again to prepare glycerol carbonate (meth)acrylate) or utilized in some other function.

[0034] Once the desired degree of conversion of one or more of the glycerol monomethacrylates or carbonates has been achieved, the reaction may be stopped and the reaction product containing the target glycerol carbonate methacrylate may then be subjected to a suitable post-treatment or purification procedure to obtain the glycerol carbonate methacrylate in the desired pure form. Such purification steps may include, for example, washing and / or neutralization to remove or deactivate the catalyst, drying, treatment with an adsorbent, decolorization and / or fractionation.

[0035] CURABLE COMPOSITIONS COMPRISING GLYCEROL CARBONATE METHACRYLATE AND ACTINALLY CURABLE OLIGOMERS - Patent application One aspect of the present invention provides a curable composition composed of glycerol carbonate methacrylate and at least one actinic radiation curable oligomer (e.g., at least one (meth)acrylate functionalized oligomer). Such compositions may be photocurable or radiation curable, i.e., curable by exposure to actinic radiation, such as UV light, visible light, or electron beam radiation. The glycerol carbonate methacrylate can function as a reactive diluent and reduce the viscosity of the at least one actinic radiation curable oligomer. Such oligomers tend to have high viscosity, especially when the molecular weight is relatively high, or even may be solid in neat form at room temperature (e.g., 25° C.). The glycerol carbonate methacrylate can make the curable composition sufficiently low in viscosity that the curable composition can be easily applied to a substrate surface at a suitable application temperature even in the absence of a solvent to form a relatively thin uniform layer. Thus, according to certain embodiments, the at least one actinically curable oligomer may have a viscosity of at least 10,000 cPs in neat form at 25° C., and the glycerol carbonate methacrylate is present in the curable composition in an amount effective to impart to the curable composition a viscosity of less than 10,000 cPs (preferably less than 2500 cPs) at 25° C.

[0036] The amount of glycerol carbonate methacrylate in the curable composition may vary as desired depending on the desired properties of both the curable composition and the cured product obtained therefrom. For example, without limitation, the curable composition may comprise a total of at least 1 wt%, at least 2 wt%, at least 5 wt%, at least 10 wt%, at least 15 wt%, at least 20 wt%, or at least 25 wt% of glycerol carbonate methacrylate based on the total weight of the curable composition. The maximum amount of glycerol carbonate methacrylate is not necessarily limited, keeping in mind that the curable composition of the present invention additionally contains at least some amount of actinic radiation curable oligomer, and optionally other components (e.g., photoinitiator and / or reactive materials other than actinic radiation curable oligomer and glycerol carbonate methacrylate, such as one or more actinic radiation curable monomers). For example, the curable composition may comprise a total of up to 95% by weight, up to 90% by weight, up to 85% by weight, up to 80% by weight, or up to 75% by weight of glycerol carbonate methacrylate, based on the total weight of the curable composition. The amount of glycerol carbonate methacrylate varies depending on the end use, but is typically 10-65% by weight, based on the total weight of the curable composition. According to certain embodiments, the curable composition is comprised of 20-30% by weight of glycerol carbonate methacrylate, based on the total weight of the curable composition.

[0037] Actinic Radiation Curable Oligomers The amount of actinically curable oligomer (e.g., (meth)acrylate-functionalized oligomer) may vary as desired depending on the type or types of oligomer used and the properties desired in both the curable composition and the cured product obtained therefrom. For example, and without limitation, the curable composition may comprise a total of at least 1 wt.%, at least 2 wt.%, at least 5 wt.%, at least 10 wt.%, at least 15 wt.%, at least 20 wt.%, or at least 25 wt.% actinically curable oligomer (e.g., (meth)acrylate-functionalized oligomer) based on the total weight of the curable composition. The maximum amount of actinically curable oligomer (e.g., (meth)acrylate-functionalized oligomer) is not necessarily limited, keeping in mind that the curable composition of the present invention additionally contains at least some amount of glycerol carbonate methacrylate and optionally other components (e.g., photoinitiator and / or reactive substances other than actinically curable oligomer and glycerol carbonate methacrylate, such as one or more actinically curable monomers). For example, the curable composition may contain up to 95% by weight, up to 90% by weight, up to 85% by weight, up to 80% by weight, or up to 75% by weight of actinically curable oligomer (e.g., (meth)acrylate-functionalized oligomer) in total, based on the total weight of the curable composition. The content of oligomer varies depending on the end use, but is typically 10-65% by weight, based on the total weight of the curable composition. According to a particular embodiment, the curable composition is composed of 20-30% by weight of oligomer, based on the total weight of the curable composition.

[0038] The type of actinic radiation curable oligomer that may be used in combination with glycerol carbonate methacrylate to produce a curable composition according to the present invention is not particularly limited, and any of the oligomers known in the art may be used. Actinic radiation curable oligomers include any oligomeric material that contains at least one functional group per molecule that can be cured (reacted) when exposed to actinic radiation. Such actinic radiation curable functional groups include functional groups that contain a site of ethylenic unsaturation (i.e., carbon-carbon double bond, C=C), such as acrylate (including cyanoacrylate), methacrylate, acrylamide, methacrylamide, maleyl, allyl, propenyl, and vinyl functional groups, and combinations thereof. The use of (meth)acrylate functionalized oligomers may be particularly advantageous. Particularly suitable for such purposes are (meth)acrylate-functionalized urethane oligomers (sometimes referred to as "urethane (meth)acrylate oligomers," "polyurethane (meth)acrylate oligomers," or "carbamate (meth)acrylate oligomers"), (meth)acrylate-functionalized epoxy oligomers (sometimes referred to as "epoxy (meth)acrylate oligomers"), (meth)acrylate-functionalized polyether oligomers (sometimes referred to as "polyester (meth)acrylate oligomers"), (meth)acrylate-functionalized urethane oligomers (sometimes referred to as "urethane ... urethane oligomers (sometimes referred to as "urethane (meth)acrylate oligomers"), (meth)acrylate-functionalized urethane oligomers (sometimes referred to as "urethane (meth)acrylate oligomers"), (meth)acrylate-functionalized urethane oligomers (sometimes referred to as "urethane (meth)acrylate oligomers"), (meth)acrylate-functionalized urethane oligomers (sometimes referred to as "urethane (meth)acrylate oligomers"), (meth)acrylate-functionalized The (meth)acrylate-functionalized oligomer is selected from the group consisting of polydiene oligomers (sometimes referred to as "polydiene (meth)acrylate oligomers"), (meth)acrylate-functionalized polycarbonate oligomers (sometimes referred to as "polycarbonate (meth)acrylate oligomers"), and (meth)acrylate-functionalized polyester oligomers (sometimes referred to as "polyester (meth)acrylate oligomers"). According to certain embodiments, at least one of the oligomers is a methacrylate-functionalized oligomer. In other embodiments, all of the oligomers present in the curable composition are methacrylate-functionalized oligomers.

[0039] According to certain aspects of the present invention, when subjected to curing to form a polymer matrix, the curable composition does not contain an amino-containing compound (oligomeric or monomeric), and as used herein, "amino" refers to a primary, secondary or tertiary amine group, but does not include any other type of nitrogen-containing group, such as amide, carbamate (urethane), urea or sulfonamide groups. Thus, the curable composition may be utilized in the form of a one-part system that is exposed to actinic radiation and cured without being combined with an amino-containing compound having an amino group, and that chemically interacts with glycerol carbonate methacrylate as part of the curing process.

[0040] (Meth)acrylate-functionalized oligomers may be defined as organic materials that are generally oligomeric in nature and contain at least one acrylate or methacrylate functional group per molecule.

[0041] Any of the (meth)acrylate functionalized oligomers known in the art may be used in the curable compositions of the present invention. According to certain embodiments, such oligomers may contain two or more (meth)acrylate functional groups per molecule. The number average molecular weight of such oligomers may vary widely, for example, from about 500 to about 50,000 Daltons. Such oligomers may be selected to enhance, among other properties, the flexibility, strength and / or modulus of the cured polymer prepared using the curable compositions of the present invention, and may be used in combination with glycerol carbonate methacrylate and, optionally, one or more (meth)acrylate functionalized monomers other than glycerol carbonate methacrylate.

[0042] Exemplary polyester (meth)acrylate oligomers include the reaction products of acrylic acid or methacrylic acid or mixtures or synthetic equivalents thereof with hydroxyl-terminated polyester polyols. The reaction process may be carried out such that all or essentially all of the hydroxyl groups of the polyester polyol are (meth)acrylated, especially when the polyester polyol is difunctional. The polyester polyols may be produced by the polycondensation reaction of polyhydroxyl-functional components (especially diols) with polycarboxylic acid-functional compounds (especially dicarboxylic acids and anhydrides). The polyhydroxyl-functional and polycarboxylic acid-functional components may each have a linear, branched, alicyclic or aromatic structure and may be used individually or as a mixture.

[0043] Examples of suitable epoxy (meth)acrylate oligomers include reaction products of acrylic or methacrylic acid, or mixtures thereof, with glycidyl ethers or esters, such as the glycidyl ethers of bisphenol compounds and their oligomers.

[0044] Suitable polyether (meth)acrylate oligomers include, but are not limited to, the condensation reaction products of acrylic acid or methacrylic acid or their synthetic equivalents or mixtures with polyetherols, which are polyether polyols, such as polyethylene glycol, polypropylene glycol, or polytetramethylene glycol. Suitable polyetherols may be linear or branched materials containing ether linkages and terminal hydroxyl groups. Polyetherols may be prepared by ring-opening polymerization of starter molecules with cyclic ethers such as tetrahydrofuran or alkylene oxides, such as ethylene oxide and / or propylene oxide. Suitable starter molecules include water, polyhydroxyl-functional materials, polyester polyols, and amines.

[0045] Polyurethane (meth)acrylate oligomers (sometimes referred to as "urethane (meth)acrylate oligomers") that can be used in the curable compositions of the present invention include urethanes based on aliphatic and / or aromatic polyester polyols and polyether polyols, and aliphatic and / or aromatic polyester diisocyanates and polyether diisocyanates, capped with (meth)acrylate end groups. Suitable polyurethane (meth)acrylate oligomers include, for example, aliphatic polyester-based urethane di- and tetraacrylate oligomers, aliphatic polyether-based urethane di- and tetraacrylate oligomers, and aliphatic polyester / polyether-based urethane di- and tetraacrylate oligomers.

[0046] In various embodiments, polyurethane (meth)acrylate oligomers may be prepared by reacting an aliphatic and / or aromatic diisocyanate with an OH-terminated polyester polyol (including aromatic, aliphatic and mixed aliphatic / aromatic polyester polyols), polyether polyols, polycarbonate polyols, polycaprolactone polyols, polyorganosiloxane polyols (e.g., polydimethylsiloxane polyols) or polydiene polyols (e.g., polybutadiene polyols), or combinations thereof, to form an isocyanate-functionalized oligomer, which is then reacted with a hydroxyl-functionalized (meth)acrylate, such as hydroxyethyl acrylate or hydroxyethyl methacrylate, to provide terminal (meth)acrylate groups. For example, the polyurethane (meth)acrylate oligomer may contain 2, 3, 4 or more (meth)acrylate functional groups per molecule. Alternative synthetic approaches may also be used to prepare suitable (meth)acrylate-functionalized urethane oligomers, such as by reacting any of the aforementioned polyols with an isocyanate-functionalized (meth)acrylate (e.g., a 1:1 reaction product of a diisocyanate and a hydroxyalkyl (meth)acrylate).

[0047] Suitable acrylic (meth)acrylate oligomers (sometimes referred to in the art as "acrylic oligomers") include oligomers that may be described as materials having an oligomeric acrylic backbone that is functionalized with one or more (meth)acrylate groups, which may be at the end of the oligomer or pendant to the acrylic backbone. The acrylic backbone may be a homopolymer, random copolymer, or block copolymer made up of repeating units of acrylic monomers. The acrylic monomers may be any monomeric (meth)acrylate, such as C1-C6 alkyl (meth)acrylates, and functionalized (meth)acrylates, such as (meth)acrylates with hydroxyl, carboxylic acid, and / or epoxy groups. Acrylic (meth)acrylate oligomers may be prepared using any procedure known in the art, for example, by oligomerizing monomers, at least a portion of which are functionalized with hydroxyl, carboxylic acid and / or epoxy groups (e.g., hydroxyalkyl (meth)acrylates, (meth)acrylic acid, glycidyl (meth)acrylate), to obtain a functionalized oligomeric intermediate, which then is reacted with one or more (meth)acrylate-containing reactants to introduce the desired (meth)acrylate functionality.

[0048] Actinic Radiation Curable Monomers The curable composition may additionally comprise at least one actinic radiation curable monomer other than glycerol carbonate methacrylate (e.g., (meth)acrylate functionalized monomer). Actinic radiation curable monomer includes any monomeric (non-oligomeric) material that contains at least one functional group per molecule that can be cured (reacted) when exposed to actinic radiation. Such actinic radiation curable functional groups include functional groups that contain a site of ethylenic unsaturation (i.e., carbon-carbon double bond, C=C), such as acrylate (including cyanoacrylate), methacrylate, acrylamide, methacrylamide, maleyl, allyl, propenyl, and vinyl functional groups, and combinations thereof. The use of (meth)acrylate functionalized monomers is particularly advantageous.

[0049] For example, according to certain embodiments, the curable composition additionally comprises at least one methacrylate-functionalized monomer other than glycerol carbonate methacrylate, but in other embodiments, the curable composition may include one or more acrylate-functionalized monomers and one or more methacrylate-functionalized monomers.

[0050] (Meth)acrylate functionalized monomers may be defined as organic materials that are generally non-oligomeric in nature and contain at least one acrylate or methacrylate functional group per molecule. According to certain aspects of the invention, the (meth)acrylate functionalized monomers used may be relatively low in molecular weight (e.g., number average molecular weight of 100 to 1000 Daltons).

[0051] The curable compositions of the present invention may include at least one (meth)acrylate-functionalized monomer, for example, containing two or more (meth)acrylate functional groups per molecule. Examples of useful (meth)acrylate-functionalized monomers containing two or more (meth)acrylate functional groups per molecule include acrylate and methacrylate esters of polyhydric alcohols (organic compounds containing two or more, e.g., 2 to 6, hydroxyl groups per molecule). Specific examples of suitable polyhydric alcohols include C 2~20 Alkylene glycol (C 2~10Glycols having alkylene groups may be preferred; for example, ethylene glycol, trimethylene glycol, 1,2-propylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, tetramethylene glycol (1,4-butanediol), 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,12-dodecanediol, cyclohexane-1,4-dimethanol, bisphenols and hydrogenated bisphenols, as well as their alkoxylated (e.g. ethoxylated and / or propoxylated) derivatives, diethylene glycol, glycerin, alkoxylated glycerin, triethylene glycol, dipropylene glycol, tripropylene glycol, trimethylolpropane, alkoxylated trimethylolpropane, ditrimethylolpropane, alkoxylated alkoxylated ditrimethylolpropane, pentaerythritol, alkoxylated pentaerythritol, dipentaerythritol, alkoxylated dipentaerythritol, cyclohexanediol, alkoxylated cyclohexanediol, cyclohexanedimethanol, alkoxylated cyclohexanedimethanol, norbornene dimethanol, alkoxylated norbornene dimethanol, norbornene dimethanol, alkoxylated norbornene dimethanol, polyols containing an aromatic ring, cyclohexane-1,4-dimethanol ethylene oxide adduct, bisphenol ethylene oxide adduct, hydrogenated bisphenol ethylene oxide adduct, bisphenol propylene oxide adduct, hydrogenated bisphenol propylene oxide adduct, cyclohexane-1,4-dimethanol propylene oxide adduct, sugar alcohols and alkoxylated sugar alcohols. Such polyhydric alcohols may be fully or partially esterified (with (meth)acrylic acid, (meth)acrylic anhydride, (meth)acryloyl chloride, etc.), provided that they contain at least two (meth)acrylate functional groups per molecule. As used herein, the term "alkoxylated" refers to compounds that contain one or more oxyalkylene moieties (e.g., oxyethylene and / or oxypropylene moieties).The oxyalkylene moiety corresponds to the general structure -RO-, where R is a divalent aliphatic moiety such as -CH2CH2- or -CH2CH(CH3)-. For example, the alkoxylated compound may contain from 1 to 25 oxyalkylene moieties per molecule.

[0052] Exemplary (meth)acrylate functionalized monomers containing two or more (meth)acrylate functional groups per molecule include ethoxylated bisphenol A di(meth)acrylate, triethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol (600) dimethacrylate, ethylene glycol ... Polyethylene glycol (200) diacrylate, 1,12-dodecanediol dimethacrylate, tetraethylene glycol diacrylate, triethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, tripropylene glycol diacrylate, polybutadiene diacrylate, methylpropanediol diacrylate, polyethylene glycol (400) diacrylate, ethoxylated 2 bisphenol A dimethacrylate, ethoxylated 3 bisphenol A dimethacrylate, ethoxylated 3 bisphenol A diacrylate, cyclohexanedimethanol dimethacrylate, cyclohexanedimethanol diacrylate, ethoxylated 10Bisphenol A dimethacrylate (the number following "ethoxylated" is the number average of oxyalkylene moieties per molecule), dipropylene glycol diacrylate, ethoxylated 4 bisphenol A dimethacrylate, ethoxylated 6 bisphenol A dimethacrylate, ethoxylated 8 bisphenol A dimethacrylate, alkoxylated hexanediol diacrylate, alkoxylated cyclohexanedimethanol diacrylate, dodecane diacrylate, ethoxylated 4 bisphenol A diacrylate; ethoxylated 10 Bisphenol A diacrylate, polyethylene glycol (400) dimethacrylate, polypropylene glycol (400) dimethacrylate, metal diacrylate, modified metal diacrylate, metal dimethacrylate, polyethylene glycol (1000) dimethacrylate, methacrylated polybutylene, propoxylated 2 neopentyl glycol diacrylate, ethoxylated 30 Bisphenol A Dimethacrylate, Ethoxylated 30 Bisphenol A diacrylate, alkoxylated neopentyl glycol diacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol diacrylate, ethoxylated 2 bisphenol A dimethacrylate, dipropylene glycol diacrylate, ethoxylated 4 bisphenol A diacrylate, polyethylene glycol (600) diacrylate, polyethylene glycol (1000) dimethacrylate, tricyclodecane dimethanol diacrylate, propoxylated neopentyl glycol diacrylate, e.g. propoxylated 2 neopentyl glycol diacrylate, diacrylates of alkoxylated fatty alcohols, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated 20Trimethylolpropane triacrylate, pentaerythritol triacrylate, ethoxylated 3 trimethylolpropane triacrylate, propoxylated 3 trimethylolpropane triacrylate, ethoxylated 6 trimethylolpropane triacrylate, propoxylated 6 trimethylolpropane triacrylate, ethoxylated 9 trimethylolpropane triacrylate, alkoxylated trifunctional acrylate esters, trifunctional methacrylate esters, trifunctional acrylate esters, propoxylated 3 glyceryl triacrylate, propoxylated 5.5 Glyceryl Triacrylate, Ethoxylated 15 Mention may be made of trimethylolpropane triacrylate, trifunctional phosphate esters, trifunctional acrylic esters, pentaerythritol tetraacrylate, di-trimethylolpropane tetraacrylate, ethoxylated 4 pentaerythritol tetraacrylate, pentaerythritol polyoxyethylene tetraacrylate, dipentaerythritol pentaacrylate and pentaacrylate esters.

[0053] In addition to glycerol carbonate methacrylate, the curable compositions of the present invention may also include one or more (meth)acrylate-functionalized monomers containing one acrylate or methacrylate functional group per molecule (referred to herein as "mono(meth)acrylate-functionalized compounds"). Any of the compounds known in the art may be used.

[0054] Examples of suitable mono(meth)acrylate functionalized monomers include, but are not limited to, mono(meth)acrylate esters of aliphatic alcohols (the aliphatic alcohols may be linear, branched or alicyclic and may be mono-, di- or polyalcohols, provided that only one hydroxyl group is esterified with (meth)acrylic acid); mono(meth)acrylate esters of aromatic alcohols (e.g., phenols, including alkylated phenols); mono(meth)acrylate esters of alkylaryl alcohols (e.g., benzyl alcohol); oligomeric and polymeric glycols, such as diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol and polypropylene glycol; mono(meth)acrylate esters of propylene glycol; mono(meth)acrylate esters of monoalkyl ethers of glycols and oligoglycols; mono(meth)acrylate esters of alkoxylated (e.g., ethoxylated and / or propoxylated) fatty alcohols (the fatty alcohols may be linear, branched or alicyclic and may be mono-, di- or polyalcohols, provided that only one hydroxyl group of the alkoxylated fatty alcohol is esterified with (meth)acrylic acid); mono(meth)acrylate esters of alkoxylated (e.g., ethoxylated and / or propoxylated) aromatic alcohols (e.g., alkoxylated phenols); caprolactone mono(meth)acrylates, and the like.

[0055] The following compounds are specific examples of mono(meth)acrylate functionalized monomers suitable for use in the curable compositions of the present invention: methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl (meth)acrylate. , tridecyl (meth)acrylate, tetradecyl (meth)acrylate, hexadecyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2- and 3-hydroxypropyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2- and 3-ethoxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, alkoxylated tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, 2-(2 -ethoxyethoxy)ethyl (meth)acrylate, cyclohexyl (meth)acrylate, glycidyl (meth)acrylate, isodecyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, lauryl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, alkoxylated phenol (meth)acrylate, alkoxylated nonylphenol (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, trimethylcyclohexanol (meth)acrylate, diethyl ethylene glycol monomethyl ether (meth)acrylate, diethylene glycol monoethyl ether (meth)acrylate, diethylene glycol monobutyl ether (meth)acrylate, triethylene glycol monoethyl ether (meth)acrylate, ethoxylated lauryl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, hydroxyethyl-butyl urethane (meth)acrylate, 3-(2-hydroxyalkyl)oxazolidinone (meth)acrylate, and combinations thereof.

[0056] Other types of actinic radiation curable monomers that may be used in the curable compositions of the present invention include, but are not limited to, cyanoacrylates, vinyl esters, 1,1-diester-1-alkenes, 1,1-diketo-1-alkenes, 1-ester-1-keto-1-alkenes, including methylene malonates and / or methylene beta diketones, and itaconates.

[0057] Stabilizers In general, it is desirable to include one or more stabilizers in the curable compositions of the present invention to provide sufficient storage stability and shelf life. Advantageously, one or more such stabilizers are present at each stage of the process used to prepare the curable compositions to prevent undesired reactions during processing of the (meth)acrylate functional groups of the components of the curable compositions. As used herein, the term "stabilizer" refers to a compound or substance that retards or prevents reaction or curing of actinic radiation-curable functional groups present in the composition in the absence of actinic radiation. However, it is advantageous to select the amount and type of stabilizer such that the composition remains curable when exposed to actinic radiation (i.e., the stabilizer does not prevent radiation curing of the composition). Typically, stabilizers effective for the purposes of the present invention are classified as free radical stabilizers (i.e., stabilizers that function by inhibiting free radical reactions).

[0058] Any of the stabilizers known in the art in connection with (meth)acrylate-functionalized compounds may be utilized in the present invention.Quinones are a particularly preferred type of stabilizer that may be utilized in the context of the present invention.As used herein, the term "quinone" includes both quinones and hydroquinones, as well as their ethers, such as monoalkyl, monoaryl, monoaralkyl, and bis(hydroxyalkyl) ethers of hydroquinone.Hydroquinone monomethyl ether is an example of a suitable stabilizer that may be utilized.

[0059] The concentration of stabilizer in the curable composition will vary depending on the particular stabilizer or combination of stabilizers selected for use, as well as the degree of stabilization desired and the susceptibility of the components in the curable composition to degradation in the absence of the stabilizer. Typically, however, the curable composition is formulated to contain 5 to 5000 ppm of stabilizer. According to certain embodiments of the present invention, during each stage of the process utilized to produce the curable composition, the reaction mixture contains at least some stabilizer, for example at least 10 ppm of stabilizer.

[0060] Photoinitiators In certain embodiments of the present invention, the curable compositions described herein comprise at least one photoinitiator and are curable by radiant energy. Photoinitiators may be considered to be any type of material that upon exposure to radiation (e.g., actinic radiation) forms a species that initiates the reaction and curing of the polymerizable organic material present in the curable composition. Suitable photoinitiators include both free radical and cationic photoinitiators and combinations thereof.

[0061] A free radical polymerization initiator is a substance that forms free radicals when irradiated. The use of free radical photoinitiators is particularly preferred. Non-limiting types of free radical photoinitiators suitable for use in the curable composition of the present invention include, for example, benzoin, benzoin ethers, acetophenone, benzil, benzil ketals, anthraquinone, phosphine oxides, α-hydroxyketones, phenylglyoxylates, α-aminoketones, benzophenones, thioxanthones, xanthones, acridine derivatives, phenazene derivatives, quinoxaline derivatives, and triazine compounds.

[0062] The amount of photoinitiator may vary as may be appropriate depending on, among other factors, the photoinitiator selected, the amount and type of polymerizable species present in the curable composition, the radiation source and irradiation conditions used, but typically the amount of photoinitiator may be from 0.05% to 5% by weight, preferably from 0.1% to 2% by weight, based on the total weight of the curable composition.

[0063] Other Additives The curable compositions of the present invention may optionally contain one or more additives instead of or in addition to the ingredients mentioned above, including, but not limited to, antioxidants / light stabilizers, light screeners / absorbers, polymerization inhibitors, foam inhibitors, flow or leveling agents, colorants, pigments, dispersants (wetting agents, surfactants), slip additives, fillers, chain transfer agents, thixotropic agents, matte agents, impact modifiers, waxes or other miscellaneous additives, including any of the additives conventionally utilized in coatings, sealants, adhesives, molding, additive manufacturing (e.g., 3D printing) or ink technologies.

[0064] The curable composition of the present invention may include one or more light blocking agents (sometimes referred to in the art as absorbers), especially when the curable composition is used as a resin in a three-dimensional printing method involving photocuring of the curable composition. The light blocking agent may be any material known in the three-dimensional printing technology, including, for example, non-reactive pigments and dyes. The light blocking agent may be, for example, a visible light blocking agent or a UV light blocking agent. Examples of suitable light blocking agents include, but are not limited to, titanium dioxide, carbon black, and organic ultraviolet light absorbers, such as hydroxybenzophenone, hydroxyphenylbenzotriazole, oxanilide, benzophenone, thioxanthone, hydroxyphenyltriazine, Sudan I, bromothymol blue, 2,2'-(2,5-thiophenediyl)bis(5-tert-butylbenzoxazole) (sold under the trade name "Benetex OB Plus"), and benzotriazole ultraviolet light absorbers.

[0065] The amount of light blocking agent may vary as desired or appropriate for a particular application. Generally, when the hardenable composition contains a light blocking agent, the light blocking agent is present in a concentration of 0.001 to 10% by weight, based on the weight of the hardenable composition.

[0066] Advantageously, the curable compositions of the present invention may be formulated to be solvent-free, i.e., free of non-reactive volatile materials (materials having a boiling point of 150° C. or less at atmospheric pressure). For example, the curable compositions of the present invention may contain little or no non-reactive solvent, for example less than 10%, or less than 5%, or less than 1%, or even 0% of non-reactive solvent based on the total weight of the curable composition. As used herein, the term non-reactive solvent refers to a solvent that does not react upon exposure to actinic radiation used to cure the curable compositions described herein.

[0067] According to another advantageous embodiment of the present invention, the curable composition is formulated so that it can be used as a one-component or one-part system, i.e., the curable composition is cured directly and is not combined with another component or second part (e.g., an amine monomer as defined in US Patent Application Publication No. 2017 / 0260418 A1) before being cured.

[0068] Use of the curable composition As mentioned above, the curable compositions according to the present invention may contain one or more photoinitiators and may be photocurable. In certain other embodiments of the present invention, the curable compositions described herein do not contain an initiator and are (at least partially) curable with electron beam energy. In other embodiments, the curable compositions described herein contain at least one free radical initiator that decomposes upon heating or in the presence of an accelerator and is chemically curable (i.e., without the need to expose the curable composition to radiation). The at least one free radical initiator that decomposes upon heating or in the presence of an accelerator may include, for example, a peroxide or an azo compound. Suitable peroxides for this purpose may include any compound, particularly any organic compound, that contains at least one peroxy (-OO-) moiety, such as dialkyl, diaryl and aryl / alkyl peroxides, hydroperoxides, percarbonates, peresters, peracids, acyl peroxides, etc. The at least one accelerator may comprise, for example, at least one tertiary amine and / or one or more other reducing agents based on metal-containing salts (e.g., carboxylates of transition metals such as iron, cobalt, manganese, vanadium, and the like, and combinations thereof). The accelerator may be selected to promote decomposition of the free radical initiator to generate active free radical species at or near room temperature, such that curing of the curable composition is achieved without the need to heat or bake the curable composition. In other embodiments, no accelerator is present and the curable composition is heated to a temperature effective to cause decomposition of the free radical initiator to generate free radical species that initiate curing of the polymerizable compounds present in the curable composition.

[0069] Advantageously, the curable compositions of the present invention may be formulated to be solvent-free, i.e., free of non-reactive volatile materials (materials having a boiling point at atmospheric pressure of 150° C. or less). For example, the curable compositions of the present invention may contain little or no non-reactive solvent, for example less than 10%, or less than 5%, or less than 1%, or even 0% non-reactive solvent based on the total weight of the curable composition.

[0070] In preferred embodiments of the invention, the curable compositions are liquid at 25° C. In various embodiments of the invention, the curable compositions described herein are formulated to have a viscosity of less than 10,000 mPa.s (cP), or less than 5000 mPa.s (cP), or less than 4000 mPa.s (cP), or less than 3000 mPa.s (cP), or less than 2500 mPa.s (cP), or less than 2000 mPa.s (cP), or less than 1500 mPa.s (cP), or less than 1000 mPa.s (cP), or even less than 500 mPa.s (cP), measured at 25° C. using a Brookfield Viscometer, Model DV-II, using a 27 spindle (spindle speed typically varies from 20 to 200 rpm depending on viscosity). In advantageous embodiments of the invention, the viscosity of the curable composition is from 200 to 5000 mPa.s (cP), or from 200 to 2000 mPa.s (cP), or from 200 to 1500 mPa.s (cP), or from 200 to 1000 mPa.s (cP) at 25° C. A relatively high viscosity may provide good performance in applications where the curable composition is heated above 25° C., such as in three dimensional printing operations utilizing machines having heated resin vats.

[0071] The curable compositions described herein may be compositions that are subject to curing by free radical polymerization, cationic polymerization, or other types of polymerization. In certain embodiments, the curable compositions are photocured (i.e., cured by exposure to actinic radiation, such as light, especially visible or UV light). End uses of the curable compositions include, but are not limited to, inks, coatings, adhesives, resins for additive manufacturing (e.g., resins for 3D printing), resins for molding, encapsulants, composites, antistatic layers, electronic applications, reusable materials, intelligent materials that can sense and respond to stimuli, packaging materials, personal care articles, articles used in agriculture, water or food processing, or animal husbandry, and biomedical materials. Thus, the curable compositions of the present invention are useful for the production of biocompatible articles. Such articles may, for example, exhibit high biocompatibility, low cytotoxicity, and / or low extractables.

[0072] Cured compositions prepared from the curable compositions described herein may be used, for example, in three-dimensional articles (the three-dimensional article may consist essentially of or may consist of the cured composition), coated articles (wherein a substrate is coated with one or more layers of the cured composition, including encapsulated articles where the substrate is completely covered by the cured composition), laminated or adhesive articles (wherein a first component of an article is laminated or adhered to a second component by the cured composition), composite articles, or printed articles (wherein the cured composition is used to imprint a graphic or the like onto a substrate such as paper, plastic, or an M-containing substrate).

[0073] Curing of the curable composition according to the present invention may be carried out by any suitable method, such as free radical and / or cationic polymerization. One or more initiators, such as free radical initiators (e.g., photoinitiators, peroxide initiators), may be present in the curable composition. Before curing, the curable composition may be applied to the substrate surface by any known conventional method, such as spraying, knife coating, roller coating, casting, drum coating, dipping, and the like, and combinations thereof. Indirect application using a transfer process may also be used. The substrate may be any commercially relevant substrate, such as a high surface energy substrate or a low surface energy substrate, such as a metal substrate or a plastic substrate, respectively. The substrate may include metal, paper, cardboard, glass, thermoplastics such as polyolefins, polycarbonates, acrylonitrile butadiene styrene (ABS) and blends thereof, composites, wood, leather, and combinations thereof. When used as an adhesive, the curable composition may be placed between two substrates and cured, whereby the substrates are bonded together by the cured composition, resulting in an adhesive article. Curable compositions according to the present invention may also be formed and cured in a bulk manner (eg, the curable composition may be cast into a suitable mold and then cured).

[0074] Curing may be accelerated or facilitated by providing energy to the curable composition, such as by heating the curable composition and / or exposing the curable composition to a radiation source, such as visible or UV light, infrared radiation, and / or electron beam radiation. Thus, the cured composition may be considered a reaction product of the curable composition formed by curing. The curable composition may be partially cured by exposure to actinic radiation, and further curing is achieved by heating the partially cured article. For example, an article (e.g., a 3D printed article) formed from the curable composition may be heated at a temperature of 40°C to 120°C for a period of 5 minutes to 12 hours.

[0075] Multiple layers of the curable composition according to the present invention may be applied to a substrate surface. The multiple layers may be cured simultaneously (e.g., by exposure to a single dose of radiation) or each layer may be cured sequentially before application of a further layer of the curable composition.

[0076] The curable compositions described herein can be used as resins in three-dimensional printing applications. Three-dimensional (3D) printing, also referred to as additive manufacturing, is a method in which 3D digital models are produced by deposition of build materials. 3D printed objects are created by utilizing computer-aided design (CAD) data of the object and sequentially building two-dimensional (2D) layers or slices corresponding to cross sections of the 3D object. Stereolithography (SL) is a type of additive manufacturing in which liquid resin is solidified by selective exposure to radiation to form each 2D layer. The radiation may be in the form of electromagnetic waves or electron beams. The most commonly applied energy source is ultraviolet, visible or infrared radiation.

[0077] Stereolithography and other photocurable 3D printing methods typically apply a low intensity light source to irradiate each layer of photocurable resin to form the desired article. As a result, the polymerization kinetics and flexural strength (green strength) of the photocurable resin of the printed article are important criteria for evaluating whether a particular photocurable resin will polymerize (cure) sufficiently when irradiated and have sufficient engineered material flexural strength to retain its integrity during the 3D printing process. As mentioned above, acrylates and methacrylates typically have different reactivities that can be explained by steric hindrance by the methyl group of the methacrylate at the alpha position of the double bond, and charge induction, which ultimately hinders the polymerization rate. However, glycerol carbonate methacrylate has been reported to have a reactivity rate 1.7 times faster than methyl methacrylate and 7 times faster than glycidyl methacrylate under similar polymerization conditions (Camara et al., European Polymer Journal 61 (2014) 133-144).

[0078] The radiation curing kinetics of copolymerization of an acrylate with a particular structure and its corresponding methacrylate generally does not result in a kinetic rate that is the average of the kinetic rates of the individual acrylates and methacrylates, since the kinetics of the methacrylates are typically predominant. However, glycerol carbonate methacrylate has been found to be atypical in its reactivity, and the inventors have discovered that glycerol carbonate methacrylate (GCMA) can be effectively used in curable compositions based on methacrylate-functionalized compounds to increase the radiation-induced curing rate of the curable composition and improve the bending strength of the cured product derived from the curable composition, making such GCMA-modified formulations particularly useful in 3D printing applications. That is, GCMA can be used in 3D printing resin compositions containing one or more other methacrylates to improve the degree of conversion achieved within a given period of time, despite the presence of a slow-reactive methacrylate.

[0079] Thus, the curable compositions of the present invention described herein are particularly useful as 3D printing resin formulations, i.e. compositions intended for use in the manufacture of three-dimensional articles using 3D printing techniques. Such three-dimensional articles may be free-standing / self-supporting or may consist essentially of or consist of the cured compositions according to the present invention. The three-dimensional articles may also be composites comprising at least one component that consists essentially of or consists of the aforementioned cured compositions and at least one further component (e.g., a metal component or a thermoplastic resin component) that is composed of one or more materials other than such cured compositions. The curable compositions of the present invention are particularly useful in digital light printing (DLP), although other types of three-dimensional (3D) printing methods are also possible using the curable compositions of the present invention (e.g., SLA, inkjet, multi-jet printing, piezoelectric printing, actinic radiation curable extrusion, and gel deposition printing). The curable compositions of the present invention may be used in three-dimensional printing operations together with another material that serves as a scaffold or support for the article formed from the curable compositions of the present invention.

[0080] The curable compositions of the present invention are therefore useful in the implementation of various three-dimensional fabrication or printing techniques, including methods in which the construction of a three-dimensional object is carried out stepwise or layer by layer. In such methods, layer formation may be carried out by solidification (hardening) of the curable composition under the action of exposure to radiation, such as visible, UV or other actinic radiation. For example, a new layer may be formed on the top surface of a growing object or on the bottom surface of a growing object. The curable compositions of the present invention may also be advantageously utilized in a method for producing a three-dimensional object by additive manufacturing, which method is carried out continuously. For example, the object may be produced from a liquid interface. Suitable methods of this kind are sometimes referred to in the art as "continuous liquid interface (or interphase) production (or printing)" ("CLIP") methods. Such methods are described, for example, in WO2014 / 126830, WO2014 / 126834, WO2014 / 126837 and Tumbleston et al., “Continuous Liquid Interface Production of 3D Objects,” Science Vol. 347, No. 6228, pp. 1349-1352 (March 20, 2015), the entire disclosures of which are incorporated herein by reference in their entirety for all purposes.

[0081] When stereolithography is performed on an oxygen-permeable window, the production of articles using the curable composition according to the invention may be possible in the CLIP technique by creating an oxygen-containing "dead zone" that is a thin uncured layer of the curable composition between the window and the surface of the cured article when the cured article is produced. In such a process, a curable composition is used where the curing (polymerization) is inhibited by the presence of molecular oxygen. Such inhibition is typically observed, for example, in curable compositions that are curable by a free radical mechanism. The desired thickness of the dead zone may be maintained by selecting various control parameters such as the photon flux and the optical and curing properties of the curable composition. The CLIP process proceeds by projecting a continuous sequence of actinic (e.g., UV) images (which may be generated, for example, by a digital light processing imaging device) through an oxygen-permeable actinic (e.g., UV)-transparent window located below a bath of the curable composition maintained in liquid form. The liquid interface below the developing (growing) article is maintained by the dead zone created above the window. The curing article is continuously withdrawn from the curable composition bath above the dead zone, and the curable composition bath may be replenished by feeding additional quantities of curable composition to the bath to make up for the amount of curable composition that is cured and incorporated into the growing article.

[0082] Given the relatively low toxicity of the glycerol carbonate methacrylate component, the hardenable composition of the present invention is particularly useful for the fabrication of articles for biomedical or skin-contact applications, such as applications in the fields of dentistry, prosthetics, implantable devices, surgical instruments, and tissue and organ replacement. Thus, in some embodiments, articles prepared from the hardenable composition are intended for use in situations where the article is in direct or intimate contact with a living organism (e.g., an animal or human) at risk of toxic effects, or with substances consumed by such organisms (e.g., food, drinking water, medicines, personal care products), for example, medical and dental articles, personal care articles, toys, packaging for food, beverages and personal care products, and articles used in the fields of food, beverage and water treatment, agriculture and animal husbandry. For such end uses, the other components of the hardenable composition should of course be selected to have similarly relatively low toxicity, including little or no tendency to induce allergic, inflammatory or sensitizing responses in living organisms, such as humans.

[0083] Aspects of the invention Exemplary, non-limiting embodiments of the present invention can be summarized as follows:

[0084] Aspect 1: A method for producing glycerol carbonate (meth)acrylate, comprising reacting glycerol mono(meth)acrylate with a carbonate selected from the group consisting of dialkyl carbonates and cyclic alkylene carbonates in the presence of a catalyst.

[0085] Aspect 2: The method of aspect 1, wherein the catalyst is selected from a Lewis acid or a Lewis base.

[0086] The method of embodiment 1, wherein the catalyst is a Bronsted base catalyst.

[0087] Aspect 4: The method of any one of aspects 1 to 3, wherein the catalyst is selected from the group consisting of alkali metal hydroxides and alkali metal alkoxides.

[0088] Aspect 5: The method of any one of aspects 1 to 4, wherein the carbonate is selected from the group consisting of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylene carbonate, and propylene carbonate.

[0089] Aspect 6: The method according to any one of aspects 1 to 5, wherein the glycerol mono(meth)acrylate and the carbonate are reacted at a temperature of 40 to 160°C.

[0090] Aspect 7: The method of any one of aspects 1 to 6, wherein the step of reacting glycerol mono(meth)acrylate with a carbonate is carried out in a liquid phase.

[0091] Aspect 8: The method of aspect 7, wherein a co-product alcohol is formed during the reacting step.

[0092] Aspect 9: The method of aspect 8, wherein the co-product alcohol is removed from the liquid phase during the reacting step.

[0093] Aspect 10: The method of any one of aspects 1 to 9, wherein the carbonate and glycerol mono(meth)acrylate are reacted in a molar ratio of carbonate:glycerol mono(meth)acrylate of 1:1 to 3:1.

[0094] Embodiment 11: The method of any one of embodiments 1 to 10, wherein the reacting step is carried out in the presence of a polymerization inhibitor.

[0095] Embodiment 12: A curable composition comprising glycerol carbonate methacrylate and at least one actinically curable oligomer (according to one embodiment, the curable composition does not comprise an actinically curable oligomer containing an amino group).

[0096] Aspect 13: The curable composition of aspect 12, wherein the at least one actinic radiation-curable oligomer comprises at least one (meth)acrylate-functionalized oligomer selected from the group consisting of (meth)acrylate-functionalized urethane oligomers, (meth)acrylate-functionalized epoxy oligomers, (meth)acrylate-functionalized polyether oligomers, (meth)acrylate-functionalized polydiene oligomers, (meth)acrylate-functionalized polycarbonate oligomers, and (meth)acrylate-functionalized polyester oligomers.

[0097]

[0043] Embodiment 14: The curable composition of embodiment 12 or 13, wherein the at least one (meth)acrylated oligomer has a viscosity of at least 10,000 cPs in neat form at 25°C, and the glycerol carbonate methacrylate is present in an amount effective to impart to the curable composition a viscosity of less than 10,000 cPs at 25°C.

[0098] Aspect 15: The curable composition of any one of aspects 12 to 14, which upon curing provides a cured polymer matrix having a higher tensile modulus as measured by ASTM D638-14 (Type IV) and a higher notched Izod impact resistance as measured by ASTM D256-10 (2018) than a cured polymer matrix obtained by curing a similar curable composition having an identical composition except that an ethoxylated 2 bisphenol A diacrylate monomer is used instead of glycerol carbonate methacrylate.

[0099]

[0031] Embodiment 16: The curable composition of any one of embodiments 12 to 15, further comprising at least one actinic radiation-curable monomer other than glycerol carbonate methacrylate.

[0100] Aspect 17: The curable composition of any one of aspects 12 to 16, further comprising at least one actinic radiation-curable monomer other than glycerol carbonate methacrylate selected from the group consisting of cyanoacrylates, vinyl esters, 1,1-diester-1-alkenes, 1,1-diketo-1-alkenes, 1-ester-1-keto-1-alkenes, and itaconates.

[0101]

[0041] Embodiment 18: The curable composition of any one of embodiments 12 to 17, further comprising at least one methacrylate-functionalized monomer other than glycerol carbonate methacrylate.

[0102] Embodiment 19: A method of additive manufacturing comprising a step of radiation curing a curable composition comprised of glycerol carbonate methacrylate and at least one (meth)acrylate functionalized oligomer, but not comprised of an amino-containing compound.

[0103] Aspect 20: A method of additive manufacturing comprising radiation curing a one-part curable composition comprised of glycerol carbonate methacrylate, wherein the one-part curable composition does not comprise an amino-containing compound and is not combined with an amino-containing compound prior to radiation curing.

[0104] Within this specification, the embodiments have been described in a manner that enables a clear and concise specification to be written, but it is intended and understood that the embodiments may be variously combined or separated without departing from the invention, For example, it is understood that all preferred features described herein are applicable to all aspects of the invention described herein.

[0105] In some embodiments, the invention herein may be construed to exclude any element or process step that does not materially affect the basic and novel characteristics of the invention. Further, in some embodiments, the invention may be construed to exclude any element or process step not specified herein.

[0106] Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope of the claims and their equivalents without departing from the invention. EXAMPLES

[0107] Example 1 This example demonstrates that glycerol carbonate methacrylate (GCMA) is effective in increasing cure rate and improving green (flexural) strength when copolymerized with other methacrylates.

[0108] The following tests (Table 1, Figure 1) were performed using the FTIR spectrum at 810 cm -1 The peak % transmission change is attributed to the in-plane and out-of-plane vibrational motion of the C=O of the (meth)acrylate system. All samples were prepared with 0.5% Irgacure® 819 photoinitiator. The change in this peak was observed for isobornyl acrylate (sold as SR506 by IBOA / Sartomer), which exhibited a normalized % transmission (%T N ) and the slowest conversion is 1.0%T in 5.1 seconds. N This was achieved with isobornyl methacrylate (sold as SR423 by IBOMA / Sartomer Corporation). Neat GCMA showed a slower 9.7% T N The combination of IBOA and IBOMA showed a slight improvement in conversion (1.6%T) compared to neat IBOMA. N ) but the combination of GCMA and IBOMA resulted in a 4.5%T NThis resulted in a conversion rate of almost three times the conversion improvement over the addition of the kinetically faster isobornyl acrylate / isobornyl methacrylate system. These results indicate that the use of GCMA in 3D printing applications in methacrylate-containing systems is highly useful for improving the degree of conversion in the presence of slow-reacting methacrylates.

[0109] [Table 1]

[0110] Similar tests were conducted involving tetrahydrofuryl acrylate (THFA), tetrahydrofuryl methacrylate (THFMA) and GCMA. The results are shown in Table 2 and Figure 2. Here, THFA gave 34.3% T when irradiated with UV light for 5.1 seconds. N The highest conversion was observed at 0.9% T N Again, the GCMA showed a reduced conversion of 9.7%T N The kinetic polymerization rate of a 1:1 blend of THFA and THFMA was 0.8%T N The combination of THFMA and GCMA resulted in a 2.4% T, a 3-fold improvement over neat THFMA or a blend of THFMA. N As demonstrated in this parallel study, GCMA accelerates the kinetics of slow-reacting methacrylates.

[0111] [Table 2]

[0112] Materials and Methods: Formulations were prepared using Sartomer's SR506, SR423, SR203 and SR285 products, as well as glycerol carbonate methacrylate (GCMA) and 0.5% Irgacure® 819 (BASF) and mixed at room temperature until homogeneous. Formulations were photocured on a Nicolet IS50 FTIR spectrophotometer equipped with a Dymax BlueWave LED Prime UVA attenuated total reflectance (ATR) accessory (A max = 385 nm). Photopolymerization is carried out at 810 cm -1 The time was then started simultaneously with kinetic data collection at regular intervals of 0.85 seconds. Monomers (all Sartomer products): SR506 - Isobornyl acrylate (IBOA) SR423 - Isobornyl methacrylate (IBOMA) SR203 - Tetrahydrofurfuryl methacrylate (THFMA) SR285 - Tetrahydrofurfuryl acrylate (THFA)

[0113] Example 2 UV-curable formulations were prepared by mixing the resin components and photoinitiator in a glass sample bottle and placing the bottle on rollers in a 60° C. oven overnight to ensure thorough mixing. After mixing, the formulations were poured into silicone molds and cured by passing the molds under a UV light source (e.g., 395 nm LED with a belt speed of 50 feet per minute) to form solid specimens for tensile testing, dynamic mechanical analysis (DMA), and notched Izod impact resistance.

[0114] Tensile data was collected using ASTM D638 (Type IV), notched Izod impact was collected using ASTM D256, glass transition temperature (defined as tan-δ peak) and glass transition onset temperature (defined as G'' peak) were collected using a TA Q800 DMA, and viscosity data was collected using a temperature controlled cone-and-plate viscometer.

[0115] FIG. 3 compares the tensile and impact properties of cured specimens of two 3D printable compositions: a blend of 50 wt% CN929 (a urethane acrylate oligomer sold by Sartomer) and 50 wt% SR348 (an ethoxylated 2-bisphenol A diacrylate monomer sold by Sartomer, containing approximately 2 moles of oxyethylene per mole), and a similar composition in which the ethoxylated BPA diacrylate monomer is replaced with 50% GCMA. In many (meth)acrylate-based 3D printing compositions, an increase in modulus is usually accompanied by a decrease in impact resistance. In this case, an increase in both properties is simultaneously achieved by changing to GCMA.

[0116] Figure 4 compares the thermal properties of three 3D printable compositions containing 50 wt% monomer and 50 wt% CN929 (a urethane acrylate oligomer sold by Sartomer). Typically, changing from a difunctional (meth)acrylate monomer to a similar monofunctional (meth)acrylate monomer, such as replacing SR348 with CD590 (a monofunctional aromatic acrylate monomer sold by Sartomer) in the above example, is accompanied by a decrease in glass transition temperature. However, replacing the difunctional SR348 with monofunctional GCMA achieves a 25°C increase in glass transition temperature, allowing 3D printed parts derived from GCMA-containing 3D printable compositions to retain their mechanical properties over a wide range of elevated temperatures.

[0117] Figure 5 shows how the room temperature viscosity of CN2881 (a highly branched, multifunctional polyester acrylate oligomer sold by Sartomer) can be reduced by blending with increasing amounts of GCMA. Figure 6 shows the viscosity vs. temperature curves for 50:50 blends of various (meth)acrylate functionalized oligomers with GCMA. CN8881 is a difunctional urethane acrylate sold by Sartomer, CN9001 is an aliphatic urethane acrylate oligomer sold by Sartomer, and CN9030 is a difunctional aliphatic urethane acrylate oligomer sold by Sartomer. Tables 3 and 4 and Figures 7 and 8 compare the tensile strength and tensile modulus of cured samples prepared from blends of various (meth)acrylate-functionalized monomers (including GCMA) and (meth)acrylate-functionalized oligomers (CN8881 - a difunctional urethane acrylate sold by Sartomer), showing the results obtained using various amounts of monomer. Monomers (all Sartomer products): SR506 - Isobornyl acrylate SR339 - 2-Phenoxyethyl acrylate SR217 - 4-tert-Butylcyclohexyl acrylate

[0118] [Table 3]

[0119] [Table 4]

[0120] Example 3 Synthesis of glycerol carbonate methacrylate To a four-neck flask equipped with an overhead stirrer, addition funnel, thermocouple, and air sparge tube was added glycerol monomethacrylate (200 g, 1.0 equiv., 1.25 mol), 4-methoxyphenol (0.3 g, 500 ppm relative to quantitative product), and sodium hydroxide (0.54 g, 1500 ppm). Diethyl carbonate (162.3 g, 1.1 equiv.) was charged to the addition funnel, and atmospheric air was bubbled continuously into the flask through the sparge tube throughout the reaction. 24.3 g of diethyl carbonate was added from the addition funnel to the flask at room temperature, and the flask was heated to 75° C. whereupon an exotherm was observed, raising the pot temperature to a reflux temperature of 90° C. The reaction mixture was cooled to 85° C., after which an additional aliquot of diethyl carbonate (105 g) was added over 5 minutes. After an additional 30 min at 85° C., the remaining diethyl carbonate was added and the reaction mixture was stirred for an additional 30 min or until conversion was greater than 80% by GC. The reaction mixture was cooled to 60° C. and placed under reduced pressure (300 Torr) to remove the ethanol by-product and facilitate conversion to product over 1 h. The crude product mixture was then heated to 90° C. under reduced pressure (<30 Torr) to remove residual diethyl carbonate and afford glycerol carbonate methacrylate (227 g, 98% GC) as a colorless oil.

Claims

1. A method for producing glycerol carbonate (meth)acrylate, comprising reacting glycerol mono(meth)acrylate with a carbonate selected from the group consisting of dialkyl carbonates and cyclic alkylene carbonates in the presence of a catalyst.

2. The process of claim 1 , wherein the catalyst is selected from a Lewis acid or a Lewis base.

3. 10. The process of claim 1, wherein the catalyst is a Bronsted base catalyst.

4. 4. The process of claim 1, wherein the catalyst is selected from the group consisting of alkali metal hydroxides and alkali metal alkoxides.

5. 5. The process according to any one of claims 1 to 4, wherein the carbonate is selected from the group consisting of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylene carbonate and propylene carbonate.

6. 6. The method according to claim 1, wherein the glycerol mono(meth)acrylate and the carbonate are reacted at a temperature of from 40 to 160°C.

7. 7. The method according to claim 1, wherein the step of reacting glycerol mono(meth)acrylate with a carbonate is carried out in the liquid phase.

8. 8. The method of claim 7, wherein a co-product alcohol is formed during the reacting step.

9. 9. The method of claim 8, wherein the co-product alcohol is removed from the liquid phase during the reacting step.

10. 10. The process according to any one of claims 1 to 9, wherein the carbonate and glycerol mono(meth)acrylate are reacted in a molar ratio of carbonate:glycerol mono(meth)acrylate of 1:1 to 3:

1.

11. 11. The method of any one of claims 1 to 10, wherein the reacting step is carried out in the presence of a polymerization inhibitor.

12. A curable composition comprising glycerol carbonate methacrylate and at least one actinic radiation curable oligomer.

13. 13. The curable composition of claim 12, wherein the at least one actinic radiation-curable oligomer comprises at least one (meth)acrylate-functionalized oligomer selected from the group consisting of (meth)acrylate-functionalized urethane oligomers, (meth)acrylate-functionalized epoxy oligomers, (meth)acrylate-functionalized polyether oligomers, (meth)acrylate-functionalized polydiene oligomers, (meth)acrylate-functionalized polycarbonate oligomers, and (meth)acrylate-functionalized polyester oligomers.

14. 14. The curable composition of claim 12 or 13, wherein the at least one (meth)acrylated oligomer has a viscosity of at least 10,000 cPS in neat form at 25° C., and the glycerol carbonate methacrylate is present in an amount effective to impart to the curable composition a viscosity of less than 10,000 cPs at 25° C.

15. During curing, ethoxylation replaces glycerol carbonate methacrylate 2 15. The curable composition of any one of claims 12 to 14, which results in a cured polymer matrix having a higher tensile modulus, as measured by ASTM D638-14 (Type IV), and a higher notched Izod impact resistance, as measured by ASTM D256-10 (2018), compared to a cured polymer matrix obtained by curing a similar curable composition having the same composition except that a bisphenol A diacrylate monomer is used.

16. 16. The curable composition of any one of claims 12 to 15, further comprising at least one actinic radiation curable monomer other than glycerol carbonate methacrylate.

17. 17. The curable composition of any one of claims 12 to 16, further comprising at least one actinic radiation curable monomer other than glycerol carbonate methacrylate selected from the group consisting of cyanoacrylates, vinyl esters, 1,1-diester-1-alkenes, 1,1-diketo-1-alkenes, 1-ester-1-keto-1-alkenes, and itaconates.

18. 18. The curable composition of any one of claims 12 to 17, further comprising at least one methacrylate-functionalized monomer other than glycerol carbonate methacrylate.

19. A method of additive manufacturing comprising the step of radiation curing a curable composition comprised of glycerol carbonate methacrylate and at least one (meth)acrylate functionalized oligomer, but not comprised of an amino-containing compound.

20. 1. A method of additive manufacturing comprising radiation curing a one-part curable composition comprised of glycerol carbonate methacrylate, wherein the one-part curable composition does not comprise an amino-containing compound and is not combined with an amino-containing compound prior to radiation curing.

Images