COMPOUNDS CONTAINING CYCLIC STRUCTURAL ELEMENTS, URETHANE/UREIDO LINKAGES AND A FREE RADICAL-POLYMERIZABLE FUNCTIONAL GROUP

Abstract

Compounds useful for formulating inks, 3D printing resins, molding resins, coatings, sealants and adhesives which exhibit reduced shrinkage stress and high hardness and stiffness when cured are described which include a single free radical-polymerizable functional group, one or more urethane and/or ureido linkages and one or more cyclic structural elements per molecule.

Claims

1. A compound having a structure in accordance with Formula (I)
Q-(R.sup.1Z.sup.1).sub.m-RZ   (I) wherein Q is a moiety containing a single free radical-polymerizable functional group, R is a urethane/ureido-containing structural unit, Z is a monovalent moiety containing at least one cyclic structural element, each R.sup.1, if present, is independently selected to be a urethane/ureido-containing structural unit which is the same as or different from R, each Z.sup.1, if present, is independently selected to be a divalent moiety containing at least one cyclic structural element and m is 0 or an integer of 1 or more.

2. The compound of claim 1, wherein the single free radical-polymerizable functional group in Q is a mono-ethylenically unsaturated functional group.

3. The compound of claim 1, wherein the single free radical-polymerizable functional group in Q is selected from the group consisting of allyl groups and (meth)acrylate groups.

4. The compound of claim 1, wherein Q is a group having structure H.sub.2C═C(R.sup.2)C(═O)—O—R.sup.3—, with R.sup.2=H, CH.sub.3 or CH.sub.2CH.sub.3 and R.sup.3=a C.sub.2 to C.sub.6 linear or branched alkylene group, an oligoether moiety or an oligoester moiety.

5. The compound of claim 1, wherein Q has structure H.sub.2C═CH—C(═O)OCH.sub.2CH.sub.2—.

6. The compound of claim 1, wherein m is 0 or an integer from 1 to 10.

7. The compound of claim 1, wherein Z is a monovalent moiety containing at least one cyclic structural element selected from the group consisting of aromatic groups and alicyclic groups.

8. The compound of claim 1, wherein Z is a monovalent moiety containing at least one alicyclic structural element selected from the group consisting of monocyclic, bicyclic, tricyclic, tetracyclic, pentacyclic and hexacyclic hydrocarbon radicals.

9. The compound of claim 1, wherein Z is a monovalent moiety containing a tricyclodecane radical.

10. The compound of claim 1, wherein m is an integer of 1 or greater than 1 and each Z.sup.1 independently is a divalent moiety containing at least one cyclic structural element selected from the group consisting of aromatic groups and alicyclic groups.

11. The compound of claim 1, wherein m is an integer of 1 or more and each Z.sup.1 independently is a divalent moiety containing at least one alicyclic structural element selected from the group consisting of monocyclic, bicyclic, tricyclic, tetracyclic, pentacyclic and hexacyclic hydrocarbon radicals.

12. The compound of claim 1, wherein m is an integer of 1 or more and each Z.sup.1 independently is a divalent moiety containing a tricyclodecane radical.

13. The compound of claim 1, wherein each R and R.sup.1, if present, independently has structure —O—C(═O)NH—R.sup.3—NH—C(═O)—O—, with R.sup.3 being a divalent hydrocarbon radical.

14. A curable composition comprised of at least one compound in accordance with claim 1 and at least one additional ethylenically unsaturated monomer or oligomer.

15. The curable composition of claim 14, wherein the at least one additional ethylenically unsaturated monomer or oligomer includes at least one compound selected from the group consisting of (meth)acrylates.

16. The curable composition of claim 14, additionally comprising at least one additive selected from the group consisting of initiators, stabilizers and fillers.

17. A cured composition which results from the curable composition of claim 14.

18. An article comprising a cured composition in accordance with claim 17.

19. The article of claim 18, wherein the article is a three-dimensional article, a coated article, a laminated article or a printed article.

20. A method of making a compound in accordance with claim 1, comprising the steps of: a) reacting a mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group with a diisocyanate in a stoichiometry effective to yield an intermediate product which is a 1:1 adduct of the mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group and the diisocyanate and which contains a single free radical-polymerizable functional group, a single isocyanate group and a urethane or ureido linkage; b) reacting the intermediate product with a mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element.

21. A method of making a compound in accordance with claim 1, comprising the steps of: a) reacting i) a mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group, ii) a diisocyanate and iii) a di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element in a stoichiometry effective to yield an intermediate product which is a 1:X:Y adduct of the mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group, the diisocyanate and the di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element and which contains a single free radical-polymerizable functional group, a single isocyanate group and two or more urethane or ureido linkages, wherein X is an integer of 1 or more and represents the number of moles of di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element incorporated in the adduct per mole of mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group and Y=X+1. and represents the number of moles of diisocyanate incorporated in the adduct per mole of mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group; b) reacting the intermediate product with a mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element.

22. A method of making a compound in accordance with claim 1, comprising the steps of: a) reacting a mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element with a diisocyanate in a stoichiometry effective to yield an intermediate product which is a 1:1 adduct of the mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element and the diisocyanate and which contains at least one cyclic structural element, a single isocyanate group and a urethane or ureido linkage; b) reacting the intermediate product with a mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group.

23. A method of making a compound in accordance with claim 1, comprising the steps of: a) reacting i) a mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element, ii) a diisocyanate and iii) a di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element in a stoichiometry effective to yield an intermediate product which is a 1:X:Y adduct of the mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element, the diisocyanate and the di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element and which contains at least two cyclic structural elements, a single isocyanate group and two or more urethane or ureido linkages, wherein X is an integer of 1 or more and represents the number of moles of di-hydroxyl, di-amino or mono-hydroxy and mono-amino functional compound containing at least one cyclic structural element incorporated in the adduct per mole of mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element and Y=X+1 and represents the number of moles of diisocyanate incorporated in the adduct per mole of mono-hydroxyl or mono-amino functional compound containing at least one cyclic structural element; b) reacting the intermediate product with a mono-hydroxyl or mono-amino functional compound containing a single free radical-polymerizable functional group.

24. A method of making a cured composition comprising curing a curable composition as defined in claim 14.

25. A method of making a three-dimensional article, comprising the steps of: a) coating a first layer of a composition comprising at least one compound in accordance with claim 1 onto a surface; b) curing the first layer to provide a cured first layer; c) coating a second layer of the composition onto the cured first layer; d) curing the second layer to provide a cured second layer adhered to the cured first layer; and e) repeating steps c) and d) a desired number of times to build up the three-dimensional article.

26. The method of claim 25, wherein the curing steps are performed by exposing the layer of the composition to radiation, preferably UV or EB radiation.

27. A method of making a coaling, an adhesive, a sealant, an ink, a 3D printing resin or a molding resin comprising using a compound as defined in claim 1.

Description

EXAMPLES

Example 1

Preparation of Monofunctional Urethane

[0152] This example demonstrates the preparation of a monofunctional urethane acrylate in accordance with the present invention based on hydroxyethyl acrylate (HEA), isophorone diisocyanate (IPDI) and tricyclodecane methanol (TCDM). In a first step, 220 g of IPDI (Desmodur® I), manufactured by Covestro), 0.86 g Irganox® 1035 stabilizer (manufactured by BASF) and 0.35 g dibutyltin dilaurate catalyst (from Sigma-Aldrich) were placed in a reaction vessel. 116 g HEA (manufactured by Nippon Shokubai) were slowly added to the reaction vessel with stirring. The contents of the reaction vessel were kept under 60° C. by controlling the rate at which the HEA was added and/or by cooling the reaction vessel with a water bath. After addition of the HEA is completed, the mixture was held at 60° C. for another hour. The reaction mixture at this point contained the following intermediate product (II), wherein IP is an isophorone moiety:

H.sub.2C═CHC(═O)OCH.sub.2CH.sub.2OC(═O)NH—IP—NCO   (II)

An air sparge was applied and 166 g TCDM (TCD Alcohol M, manufactured by Oxea) were then slowly added to the reaction mixture with stirring at a rate effective to keep the temperature of the reaction mixture below 80° C. The reaction mixture was then held at 80° C. with stirring after the addition of TCDM was completed until the residual isocyanate content dropped below 0.06 wt %. The product obtained was a clear liquid having a viscosity of 9300 mPa.s (cP) at 75° C. The reaction product contained a monofunctional urethane acrylate having the following structure (III), wherein IP is an isophorone moiety and TCD is a tricyclodecane moiety:

H.sub.2C═CHC(═O)OCH.sub.2CH.sub.2OC(═O)NH—IP—NHC(═O)OCH.sub.2-TCD  (III)

Example 2

[0153] This example describes the preparation and curing of formulations containing monofunctional compounds in accordance with the present invention.

[0154] The following components were used: [0155] CN991 aliphatic polyester-based urethane diacrylate oligomer (Sartomer USA, LLC). [0156] SR833S tricyclodecane dimethanol diacrylate (Sartomer USA, LLC). [0157] SR531 cyclic trimethyolpropane formal acrylate (Sartomer USA, LLC). [0158] Monofunctional Urethane Acrylate A: prepared in accordance with Example 1. [0159] Monofunctional Urethane Acrylate B and C: reaction product of tricyclodecane dimethanol monoacrylate, dicyclohexylmethane diisocyanate, tricyclodecane dimethanol and tricyclodecane methanol. [0160] Irgacure® 819 photoinitiator (BASF). [0161] Formulation 2-A and 2-B each contained 40 parts by weight CN991, 30 parts by weight SR833S, 10 parts by weight SR531 and 0.5 parts by weight Irgacure® 819 photoinitiator. Formulation 2-A additionally contained 20 parts by weight Monofunctional Urethane Acrylate A, Formulation 2-B additionally contained 20 parts by weight Monofunctional Urethane Acrylate B and Formulation 2-C additionally contained 20 parts by weight Monofunctional Urethane Acrylate C.

Formulation Testing Protocol

[0162] Each combination was prepared through standard heating and mixing practices. Once formulations are completely homogenous and thoroughly mixed, viscosity measurements are typically the first performance criteria to be taken. Viscosity measurements are performed using a Brookfield cup-and-bob style viscometer in which ample time is provided to reach a stable temperature and viscosity readout.

[0163] Molds were cast in silicone rubber to prepare samples for each mechanical test. Blends were poured into molds to create the shapes according to ASTM D638 for tensile testing, ASTM D256 for IZOD impact resistance, ASTM D2240 for shore hardness or ISO78 for flexural tests. Once the blends are cast into the molds, they are then cured through exposure to ultraviolet light. 100 fpm (0.508 m/s) line speed with a 600 W/in.sup.2 (930 kW/m.sup.2) V-Bulb spectrum was used to cure the example formulations. Cured samples are removed from the mold and may undergo additional polishing and notching for specific testing.

[0164] Tensile test controls around strain rate, pre-load and toe compensation are according to ASTM D638. Breaks are expected within the gauge length and material failure beyond the gauge lengths are excluded from the sample population. Typical sample population is greater than (3) three samples per formulation. Modulus, strength, elongation and energy to break values are all outlined in and are in accordance with ASTM D638.

[0165] Impact test controls around hammer selection and sample preparation are according to ASTM D256. Breaks are expected to be complete breaks, with any partial breaks or tears being excluded from the sample population. Sample population is greater than (5) five samples per formulation. Impact strength values in joules/meter are recorded and calculated in accordance to ASTM D256.

[0166] Shore hardness measurements according to ASTM D2240 were performed on a sample population of (3) test specimens. Samples with improper levels of cure were excluded and values were recorded on the Shore D scale for hardness.

[0167] Flexural testing for modulus and flexural strength values were according to ISO-78. Breaks or maximum flexural strengths were expected within 5% deflection, deviations from this excluded the samples from the population. Modulus and strength values were calculated according to the ISO standard and recorded for comparison.

[0168] The results obtained are shown in Table 1:

TABLE-US-00001 TABLE 1 Example 2-A Example 2-B Example 2-C Viscosity before curing at 25° C. 2120 4900 6628 (cP or mPa .Math. s) Tensile Properties (ASTM D638, Type IV Dogbones) Strength (psi) 4,400 7,690 8,050 Elongation (%) 22.3 7.3 8.5 Modulus (psi) 70,277 138,062 134,175 Izod Impact Resistance (ASTM D256, Notched Samples) Resistance (J/m) 18.5 40.8 42.7 Flexural Strength using 3-Point Bending (ISO 78) Flexural Strength (psi/MPa)  12,500/86.2  12,589/87.8  13,938/96.1 Elastic Modulus (psi/MPa) 290,700/2004 304,000/2096 312,311/2153

Example 3

[0169] Additional testing was performed to examine how a monofunctional urethane acrylate in accordance with the present invention performs in combination with other types of (meth)acrylic monomers. Formulations were prepared as shown in Table 2, generally following the protocol of Example 2; the listed amounts of the formulation components are in parts by weight.

[0170] The following components were used: [0171] Monofunctional urethane acrylate: Prepared in accordance with Example 1. [0172] SR256: 2(2-ethoxyethoxy) ethyl acrylate (Sartomer USA, LLC). [0173] SR730: ethyl triglycol methacrylate (Sartomer USA, LLC). [0174] SR423: isobornyl methacrylate (Sartomer USA, LLC). [0175] CN131: aromatic monoacrylate oligomer (Sartomer USA, LLC). [0176] SR454: ethoxylated (3) trimethylolpropane triacrylate (Sartomer USA, LLC). [0177] SR531: cyclic trimethylolpropane formal acrylate (Sartomer USA, LLC). [0178] SR833 tricyclododecane dimethanol diacrylate. [0179] Irgacure® 819 photoinitiator (BASF).

[0180] Good compatibility between many types of traditional acrylic monomers and the inventive monofunctional urethane acrylate was found. The physical properties of the formulations after being cured are shown in Table 2.

TABLE-US-00002 TABLE 2 3A 3B 3C 3D Monofunctional 40 40 40 40 Urethane Acrylate SR256 30 SR730 30 SR423 30 CN131 30 SR454 30 SR531 30 30 SR833 30 Additional Photoinitiator Package Irgacure ® 819 0.5 0.5 0.5 0.5 Brookfield Viscosity Results - Cup and Bob style Viscometer Viscosity @ 25° C. 70 1000 330 600 (cP or mPa .Math. s) ASTM D638 - Tensile Properties using Type IV Dogbones Strength (psi/MPa) 110/0.758 5,650/39.0 4,680/32.3 1,310/9.03 Elongation (%) 12.0 1.2 2.8 0.8 Modulus (psi) 300/2.07  120,450/830   131,600/907   59,080/407