Fluorinate polyacrylate coating composition, the preparation method therefore and use thereof

Abstract

The embodiments herein relate to a composition of a fluorinated polyurethane acrylate resin and a polyurethane acrylate resin, which, upon curing, is durable and has anti-stain and anti-scratch properties. The preparation of the composition is conducted with a one-pot multicomponent synthesis process, wherein multiple components are put together to carry out reactions simultaneously. The process is especially suitable for industrial scale production, and open for adding additive components to further adjust the performance of the prepared composition. The embodiments herein also relate to oligomers prepared in the synthesis process, as well as the use of the composition or oligomer to form a coating onto a substrate.

Claims

1. A coating composition comprising: (a) a polyacrylate oligomer of the following structure (I) ##STR00010## and (b) a fluorinated polyacrylate oligomer of the following structure (II) ##STR00011## wherein, U originates from an isocyanate structure that had at least two —N═C═O functional groups; A originates from a diol or polyol structure selected from the group consisting of ethylene glycol, diethylene glycol, neopentyl glycol, 1,6-hexanediol, cyclohexanedimethanol, polyester diols, polycarbonate diols, polyether diols, polyethylene glycol 200 (PEG200), polyethylene glycol 400 (PEG400), polyethylene glycol 600 (PEG600), polypropylene glycol 1000 (PPG1000), and a mixture thereof; F originates from a fluorinated diol or polyol structure, or a perfluoropolyether structure that contained at least two hydroxyl groups, or a mixture thereof; B originates from a structure that had at least one double bond and at least one hydroxyl group; n.sub.1, n.sub.2, n.sub.3 and n.sub.4 are integers, the sum of n.sub.1 and n.sub.2 is ranging from 0 to 20, the sum of n.sub.3 and n.sub.4 is ranging from 1 to 20.

2. The coating composition according to claim 1, wherein the weight ratio between the oligomers (I) and (II) is from 90:10 to 10:90.

3. The coating composition according to claim 1, wherein U originates from a diisocyanate structure selected from the group consisting of 1,6-hexane diisocyanate, isophorone diisocyanate, 4,4′-diphenyl-methane-diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, xylylene diisocyanate, tolylene-2,4-diisocyanate, and a mixture thereof.

4. The coating composition according to claim 1, wherein B originates from a hydroxyl (meth)acrylate structure that contains at least one (meth)acryloyl group and one hydroxyl group, selected from the group consisting of 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, 1-hydroxybutyl(meth)acrylate, neopentylglycolmono(meth)acrylate, 1,6-hexanediolmono(meth)acrylate, polycaprolactone polyol mono(meth)acrylate, pentaerythritolpenta(meth)acrylate, dipentaerythritolpenta(meth)acrylate, and a mixture thereof.

5. The coating composition according to claim 1, wherein F is selected from structures originating from the group consisting of: 2,2,3,3-tetrafluoro-1,4-butanediol; 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol; 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoro-1,8-octanediol; 2,2,3,3,4,4,5,5,6,6,7,7,8,8-tetradecafluoro-1,9-nonanediol; 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluoro-1,10-decanediol; and 1H,1H,12H,12H-Perfluoro-1,12-dodecanediol.

6. A method for preparing the coating composition according to claim 1, comprising steps of: a) preparing a solution of a fluorinated diol or polyol or a perfluoropolyether that contains at least two hydroxyl groups, or a mixture thereof in a solvent; b) dropping the solution of step a) into an isocyanate that has at least two isocyanate functional groups, forming a mixture which is heated to 50 to 60° C., and maintaining the temperature at 50 to 60° C. for 1 to 2 hours, to form a structure -U-F-U- to obtain a reaction mixture comprising structure -U-F-U-; c) adding a diol or polyol selected from the group consisting of ethylene glycol, diethylene glycol, neopentyl glycol, 1,6-hexanediol, cyclohexanedimethanol, polyester diols, polycarbonate diols, polyether diols, polyethylene glycol 200 (PEG200), polyethylene glycol 400 (PEG400), polyethylene glycol 600 (PEG600), polypropylene glycol 1000 (PPG1000), and a mixture thereof into the reaction mixture comprising structure -U-F-U- of step b), together with unreacted isocyanate, with maintaining the temperature at 50 to 60° C. for 1 to 2 hours, to form structures -(U-A).sub.n3-U-F-U-(A-U).sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2 to obtain a reaction mixture comprising structures -(U-A).sub.n3-U-F-U-(A-U).sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2; d) at a temperature of 80 to 90° C. adding a monomer that has at least one double bond and at least one hydroxyl group into the reaction mixture comprising structures -(U-A).sub.n3-U-F-U-(A-U).sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2- of step c), with maintaining the temperature at 80 to 90° C. for 1 to 2 hours to form structures B-(U-A).sub.n3-U-F-U-(A-U).sub.n4-B (II) and B-(U-A)n.sub.1-U-(A-U).sub.n2-B (I).

7. A coating composition comprising: (a) a polyacrylate oligomer of the following structure (I) ##STR00012## and (b) a fluorinated polyacrylate oligomer of the following structure (II) ##STR00013## wherein, U originates from an isocyanate structure that had at least two —N═C═O functional groups; A originates from a diol or polyol structure; F is selected from structures originating from the group consisting of: HO(CH.sub.2CH.sub.2O).sub.nCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.2CH.sub.2(OCH.sub.2CH.sub.2).sub.nOH HOCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.2CH.sub.2OH HOH.sub.2C(CF.sub.3)FC(CF(CF.sub.3)CF.sub.2O).sub.nCF(CF.sub.3)CH.sub.2OH HOH.sub.2C(CF.sub.3)CF(CF.sub.2CF.sub.2O).sub.nCF(CF.sub.3)CH.sub.2OH HOH.sub.2CCF.sub.2(CF.sub.2CF.sub.2O).sub.nCF.sub.2CH.sub.2OH HOH.sub.2CF.sub.2C(CF.sub.2CF.sub.2OCF.sub.2CF.sub.2CF.sub.2O).sub.nCF.sub.2CH.sub.2OH HOH.sub.2CCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.m(CF.sub.2O).sub.nCF.sub.2CH.sub.2CH.sub.2OH; B originates from a structure that had at least one double bond and at least one hydroxyl group; n.sub.1, n.sub.2, n.sub.3 and n.sub.4 are integers, the sum of n.sub.1 and n.sub.2 is ranging from 0 to 20, the sum of n.sub.3 and n.sub.4 is ranging from 1 to 20; wherein m is from 1 to 50, n is from 1 to 50, p is from 1 to 5, q is from 1 to 5.

8. The coating composition according to claim 7, wherein the weight ratio between the oligomers (I) and (II) is from 90:10 to 10:90.

9. The coating composition according to claim 7, wherein U originates from a diisocyanate structure selected from the group consisting of 1,6-hexane diisocyanate, isophorone diisocyanate, 4,4′-diphenyl-methane-diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, xylylene diisocyanate, tolylene-2,4-diisocyanate, and a mixture thereof.

10. The coating composition according to claim 7, wherein B originates from a hydroxyl (meth)acrylate structure that contains at least one (meth)acryloyl group and one hydroxyl group, selected from the group consisting of 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, 1-hydroxybutyl(meth)acrylate, neopentylglycolmono(meth)acrylate, 1,6-hexanediolmono(meth)acrylate, polycaprolactone polyol mono(meth)acrylate, pentaerythritolpenta(meth)acrylate, dipentaerythritolpenta(meth)acrylate, and a mixture thereof.

11. A method for preparing the coating composition according to claim 7, comprising steps of: a) preparing a solution of a fluorinated diol or polyol, or a perfluoropolyether selected from the group consisting of: HO(CH.sub.2CH.sub.2O).sub.nCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.2CH.sub.2(OCH.sub.2CH.sub.2).sub.nOH HOCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.p(CF.sub.2O).sub.qCF.sub.2CH.sub.2OH HOH.sub.2C(CF.sub.3)FC(CF(CF.sub.3)CF.sub.2O).sub.nCF(CF.sub.3)CH.sub.2OH HOH.sub.2C(CF.sub.3)CF(CF.sub.2CF.sub.2O).sub.nCF(CF.sub.3)CH.sub.2OH HOH.sub.2CCF.sub.2(CF.sub.2CF.sub.2O).sub.nCF.sub.2CH.sub.2OH HOH.sub.2CF.sub.2C(CF.sub.2CF.sub.2OCF.sub.2CF.sub.2CF.sub.2O).sub.nCF.sub.2CH.sub.2OH HOH.sub.2CCH.sub.2CF.sub.2O(CF.sub.2CF.sub.2O).sub.m(CF.sub.2O).sub.nCF.sub.2CH.sub.2CH.sub.2OH, wherein m is from 1 to 50, n is from 1 to 50, p is from 1 to 5, and q is from 1 to 5, or a mixture thereof in a solvent; b) dropping the solution of step a) into an isocyanate that has at least two isocyanate functional groups, forming a mixture which is heated to a temperature of 50 to 60° C., and maintaining the temperature at 50 to 60° C. for 1 to 2 hours, to form a structure -U-F-U-to obtain a reaction mixture comprising structure -U-F-U-; c) adding a diol or polyol selected from the group consisting of ethylene glycol, diethylene glycol, neopentyl glycol, 1,6-hexanediol, cyclohexanedimethanol, polyester diols, polycarbonate diols, polyether diols, polyethylene glycol 200 (PEG200), polyethylene glycol 400 (PEG400), polyethylene glycol 600 (PEG600), polypropylene glycol 1000 (PPG1000), and a mixture thereof into the reaction mixture comprising structure -U-F-U-of step b), -U-F-U-, together with unreacted isocyanate, with maintaining the temperature at 50 to 60° C. for 1 to 2 hours, to form structures -(U-A).sub.n3-U-F-U-(A-U).sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2 to obtain a reaction mixture comprising structure -(U-A).sub.n3-U-F-U-(A-U) .sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2; d) at a temperature of 80 to 90° C. adding a monomer that has at least one double bond and at least one hydroxyl group into the reaction mixture comprising structures -(U-A).sub.n3-U-F-U-(A-U).sub.n4- and -(U-A).sub.n1-U-(A-U).sub.n2- of step c), with maintaining the temperature at 80 to 90° C. for 1 to 2 hours to form structures B-(U-A).sub.n3-U-F-U-(A-U).sub.n4-B (II) and B-(U-A).sub.n1-U-(A-U).sub.n2-B (I).

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The above and other objectives, features and advantages of the embodiments herein will become more apparent to those of ordinary skill in the art by describing the embodiments thereof with reference to the accompanying drawings.

(2) FIGS. 1, 2, and 3 show the GPC spectrum obtained according to examples 1, 2, and 3, respectively;

(3) FIGS. 4, 5, and 6 show the IR spectrum obtained according to examples 1, 2, and 3, respectively;

(4) FIGS. 7, 8, and 9 show the NMR spectra obtained according to examples 1, 2, and 3, respectively;

(5) FIG. 10 shows the comparison of oil-based ink repellence on different UV resins.

EXAMPLES

(6) The embodiments herein will be elucidated with reference to the following examples. These are intended to illustrate the embodiments herein but are not to be construed as limiting in any manner the scope thereof.

(7) Raw MATERIAL

(8) Perfluoropolyether (E-10H, Solvay), Dipentaerythritol hexaacrylate (SR399, Sartomer), Pentaerythritol acrylate(SR444D, Sartomer), Cyclohexanedimethanol (CHDM, CAS No. 105-08-8, Sigma-Aldrich), PEG600 (600PU, Clariant), Di-isocyanates (HDI and IPDI, Wanhua)) and Trimer of HDI (HT100, Wanhua).

(9) Measurement Method and Apparatus

(10) Number average molecular weight (Mn) and weight average molecular weight (Mw) of the resins were measured by gel permeation chromatography (GPC). GPC was conducted with a commercially available polymer weight measuring apparatus (apparatus name: Agilent 1200). GPC samples were prepared by diluting fluorinated resins with tetrahydrofuran (THF) to 0.1 wt. % and pass through 0.5 μm filter.

(11) All FtIR spectra were obtained at a resolution of 4 cm.sup.−1 by using PerkinElmer Spectrum 100 FTIR with ATR system. The wave-number range was selected from 4000 to 450 cm.sup.−1 and 32 scans were averaged to reduce the noise.

(12) For NMR testing, samples were dissolved in a mixture solvent of CDCl.sub.3 and DMSO, and measured by NMR (Nuclear Magnetic Resonance) spectroscopy. The NMR data was obtained in a 400 MHz NMR system using a 5 mm probe at room temperature. The sample was measured by means of 1D (1H, 13C) and 2D (COSY, HMQC) experiment.

Example 1—Synthesis Process

(13) HDI (30.86 g) and dibutyl tin dilaurate (0.3 g) and BHT (0.3 g) were placed into a four-neck round bottom flask that was equipped with an agitator and a condenser. Perfluoropolyether diol (0.6 g) was dissolved in methyl isobutyl ketone (MiBK) and added to the mixture and heated to 60° C. The mixture was cooked at 60° C. for 1 hour. Then cyclohexanedimethanol (CHDM) (13.23 g) was dropped into the mixture within one hour at 60° C. and the mixture was cooked at 60° C. for one hour. Finally, dipentaerythritol hexaacrylate (DPHA) (246 g) was added dropwise within 1 hour at 90° C. and the mixture was cooked at 90° C. for 1 hour or more until NCO group completely disappeared.

(14) The GPC results showed the distribution of the prepared resin, as seen in FIG. 1. The IR spectra showed the functional groups of the prepared resin, as seen in FIG. 4; The NMR spectra showed .sup.1H and .sup.13C of the prepared resin, as shown in FIG. 7.

Example 2—Synthesis Process

(15) HDI (50.37 g) and dibutyl tin dilaurate (0.3 g) and BHT (0.3 g) were placed into a four-neck round bottom flask that was equipped with an agitator and a condenser. Perfluoropolyether diol (0.6 g) was dissolved in methyl isobutyl ketone (MiBK) and added to the mixture and heated to 60° C. The mixture was cooked at 60° C. for 1 hour. Then PEG600 (79.89 g) was dropped into the mixture within one hour at 60° C. and the mixture was cooked at 60° C. for one hour. Finally, pentaerythritol acrylate (PETA) (169.74 g) was added dropwise within 1 hour at 90° C. and the mixture was cooked at 90° C. for 1 hour or more until NCO group completely disappeared.

(16) The GPC results showed the distribution of the prepared resin, as seen in FIG. 2. The IR spectra showed the functional groups of the prepared resin, as seen in FIG. 5; The NMR spectra showed .sup.1H and .sup.13C of the prepared resin, as shown in FIG. 8.

Example 3—Synthesis Process

(17) IPDI (9.14 g) and dibutyl tin dilaurate (0.1 g) and BHT (0.1 g) were placed into a four-neck round bottom flask that equipped with an agitator and a condenser. Pentaerythritol acrylate (PETA) (20.97 g) was dropped into the mixture within 1 hour at 60° C. and the mixture was cooked at 60° C. for 1 hour. Then Perfluoropolyether diol (69.89 g) was dissolved in methyl isobutyl ketone (MiBK) and added to the mixture and heated to 80° C. The mixture was cooked at 80° C. for 1 hour to form the pre fluorinated oligomer.

(18) HDI trimer in BAc (90%) (88.65 g) and dibutyl tin dilaurate (0.3 g) and BHT (0.3 g) were placed into a four-neck round bottom flask that was equipped with an agitator and a condenser. Pre fluorinated oligomer (0.86 g) was added to the mixture and heated to 60° C. The mixture was cooked at 60° C. for 1 hour. Then pentaerythritol acrylate (PETA) (211.32) was dropped into the mixture within 1 hour at 80° C. and the mixture was cooked at 90° C. for 1 hour or more until NCO group completely disappeared.

(19) The GPC results showed the distribution of the prepared resin, as seen in FIG. 3. The IR spectra showed the functional groups of the prepared resin, as seen in FIG. 6; The NMR spectra showed .sup.1H and .sup.13C of the prepared resin, as shown in FIG. 9.

Example 4—Formation of Coatings

(20) Samples of the resin composition prepared according to example 1 were cured singly and mixed with other resin to form the coating films.

(21) Two samples of the resin prepared according to example 1 were diluted with a mixed solvent of methyl isobutyl ketone (MiBK) and butyl acetate (BAc), sprayed onto a PC/ABS substrate, and then cured by exposure to UV light and being heated to 120° C., respectively.

(22) A sample of the resin prepared according to example 1 was mixed with another UV resin (EM2692 available from Eternal) in a weight ratio of 7:3, sprayed onto a PC/ABS substrate, and then cured by exposure to UV light.

(23) The results showed that the composition of the embodiments herein was capable of being cured by either exposure to ultraviolet light or heating at a temperature above 120° C. The dual curing mechanism allows the composition of the embodiments herein to mix with different types of other resins, including thermosetting resins and UV curable resins.

Example 5—Liquid Contact Angle Test

(24) Liquid contact angle tests were conducted for the fluorinated resins of the embodiments herein. The water and oil contact angles of coating film surface were measured with a commercially available apparatus named Dataphysics OCA20/6.

(25) Two samples of coating-forming resins were prepared for comparison. One was a common UV resin (UX-8800WIBAC20, KAYAKU CHEMICAL(WUXI) CO., LTD), and the other one was the composition prepared according to example 1. Both of the samples were applied onto PC/ABS substrates and cured by exposure to ultraviolet light.

(26) Water contact angle was measured on top of the cured coatings, respectively, with Sessile drop method. The droplets were set as 3 μl/droplet, and the measurement temperature was about 20° C. The test results are shown in the table 1 below.

(27) n-Hexadecane contact angle was measured similarly with the same method. The droplets were set as 2 μl/droplet, and the measurement temperature was about 20° C. The test results are shown in the table 1 below as well.

(28) TABLE-US-00001 TABLE 1 the liquid contact angle of cured samples Resin Water contact angle Hexadecane contact angle UV resin 64.4 <10 fluorinated resin 110.5 68.7

Example 6—Oil-Based Ink Repellence and Anti-Scratch Performance Test

(29) Oil-based ink repellence tests were conducted for the fluorinated polymers of the embodiments herein.

(30) Two samples of coating-forming resins were prepared for comparison. One was a common UV resin (UX-8800WIBAC20, KAYAKU CHEMICAL(WUXI) CO., LTD), and the other one was the composition prepared according to example 1. Both of the samples were applied onto PC/ABS substrates and cured by exposure to ultraviolet light.

(31) Pens with different colors of oil-based inks were used to write and draw on top of the cured coatings, respectively. Pictures were taken to show the different appearance of the inks wrote onto the cured coatings, see (a) and (b) of FIG. 10. It was seen that the inks wrote on the cured coating of the common UV resin were well spread and shown as regular lines, and that the inks wrote on the cured coating of the composition prepared according to example 1 were barely spread, while instead, shrank into small liquid beads, indicating that the latter coating surface has strong repellence to the oil-based inks. The oil-based inks wrote on the cured coating formed with the composition prepared according to example 1 were easily wiped off, with substantially no stain remains (not shown in the picture).

(32) Anti-scratch performance of the coatings was tested by scratching the coatings 500 cycles with steel wool under 1 Kg gram load. Upon test, the cured coating formed with the composition prepared according to example 1 still represented excellent oil-based ink repellence and without any visible scratch marks, as seen in (c) of FIG. 10.