Polyphenylsiloxane with alkoxysilyl functionalized isocyanurate adhesion promoter

Abstract

The present invention relates to a composition comprising a) one or more compounds of Formula 1; b) a divinyl-terminated polyphenylsiloxane; c) a vinyl-terminated polyphenylsiloxane resin; d) a hydrogenphenylsiloxane; and e) a hydrosilylation catalyst; where R, DH, x, m, and n are as defined herein. The composition of the present invention is useful as a coating for electronic devices.

Description

[0001] Polyphenylsiloxane with Alkoxysilyl Functionalized Isocyanurate Adhesion Promoter Background of the Invention

[0002] The present invention relates to a composition comprising a polyphenylsiloxane and an alkoxysilyl functionalized isocyanurate adhesion promoter. Polyphenylsiloxanes are widely used in coatings for applications that require optical clarity and high modulus such as electronic devices because of their high refractive index and good mechanical properties. Unfortunately, the inherent hardness of these coatings causes them to readily delaminate from a variety of substrates to which they are adhered. Inasmuch as the properties of hardness and adhesion are both desirable, it would be an advance in the art of coatings for electronic devices to find compositions that form coatings with optical clarity, acceptable hardness, and excellent adhesion.

[0003] Summary of the Invention

[0004] The present invention addresses a need in the art by providing a composition comprising: a) one or more compounds of Formula 1 :

[0005] o

[0006] N X

[0007] O^N^O

[0008]

[0009] Si(OMe)?

[0010] Formula 1

[0011] b) a divinyl-terminated polyphenylsiloxane;

[0012] c) a vinyl-terminated polyphenylsiloxane resin;

[0013] d) a hydrogenphenylsiloxane; and

[0014] e) a hydrosilylation catalyst;

[0015] where X is a double bond or -CH2CH2-Si(CH3)2OSi(CH32-CH2CH2-Si(OCH3)3. The composition of the present invention is useful as a coating for electronic devices. Detailed Description of the Invention

[0016] The present invention is a composition comprising:

[0017] a) one or more compounds of Formula 1 :

[0018]

[0019] Si(OMe)3

[0020] Formula 1

[0021] b) a divinyl-terminated polyphenylsiloxane;

[0022] c) a vinyl-terminated polyphenylsiloxane resin;

[0023] d) a hydrogenphenylsiloxane; and

[0024] e) a hydrosilylation catalyst;

[0025] where X is a double bond or -CH2CH2-Si(CH3)2OSi(CH3)2-CH2CH2-Si(OCH3)3.

[0026] The compound of Formula 1 is typically used as a mixture of compounds of Formula la and Formula lb:

[0027] ■ Si 1 / 6J Si..

[0028] Si(OMe)3Formula la Formula lb

[0029]

[0030] The concentration of the one or more compounds of Formula 1 is preferably in the range of from 0.1 or from 0.2 or from 0.3 weight percent, to 5 or to 2 or to 1 weight percent, based on the weight of the composition.

[0031] The term “divinyl-terminated polyphenylsiloxane” refers to a compound of the following Formula 2:

[0032]

[0033] Formula 2

[0034] where Ph is phenyl; each R' is independently Ci-Ce-alkyl or phenyl; and n is from 1 or from 5 or from 10 to 500 or to 200 or to 100. Preferred Ci-C&-alkyl groups are methyl groups. Preferably, each R' is methyl. Preferably, the concentration of the divinyl-terminated polyphenylsiloxane, is in the range of from 1 or from 2 or from 4 weight percent, to 30 or to 10 or to 8 weight percent, based on the weight of the composition.

[0035] The vinyl-terminated polyphenylsiloxane resin is conveniently prepared by reacting together a tri-Ci-Ce-alkoxyphenylsilane and a compound of Formula 3:

[0036]

[0037] Formula 3

[0038] where n' is from 1 to 20, preferably to 10, and more preferably to 5; most preferably, n' is 1 and each R' is independently methyl or phenyl. The most preferred vinyl-terminated polyphenylsiloxane resin - MMePhV1aTPhb, where a and b are mole fractions - can be conveniently prepared by contacting trimethoxyphenylsilane with l,3-dimethyl-l,3-diphenyl-l,3-divinyldisiloxane in the presence of an acid catalyst. Mole fraction “a” is preferably in the range of from 0.10 to 0.40 and mole fraction “b” is preferably in the range of from 0.60 to 0.90.

[0039] MMePhV1is represented by the following fragment: Ph

[0040] ' -si-o-

[0041]

[0042] Me

[0043] and TPhis represented by the following fragment:

[0044] Ph

[0045] O - Si - <3

[0046]

[0047] where the dotted lines represent bonds to other silicon atoms in the vinyl-terminated polyphenylsiloxane resin. Preferably, the concentration of the vinyl-terminated polyphenylsiloxane resin is in the range of from 50 to 80 weight percent, based on the weight of the composition.

[0048] The term “hydrogenphenylsiloxane” refers to a compound of Formula 4:

[0049] Me / Ph \ Me

[0050] I _ / j LI

[0051]

[0052] M Ie T \Ri" / T1T1M\e

[0053] Formula 4

[0054] where each R is independently Ci-Ce-alkyl or phenyl; and m is from 1 to 50 or to 20 or to 10. Preferably m is 1. Preferred Ci-Ce-alkyl groups are methyl groups. Preferably, each R is phenyl. Preferably, the concentration of the hydrogenphenylsiloxane is in the range of from 10 to 30 weight percent.

[0055] The hydrosilylation catalyst is a catalyst that promotes hydrosilylation. Examples of suitable hydrosilylation catalysts include platinum(II) acetoacetonate, platinum(O) 1,3-divinyl-l, 1,3,3-tetramethyldisiloxane complex and trimethyl(methylcyclopentadienyl)platinum (IV). The composition may further contain an inhibitor for the platinum catalyst such as phenylbutynol or methyl(tris(l,l-dimethyl-2-propynyl) oxy) silane, and a pigment such as STAN-TONE 40SP03 Blue pigment (active ingredient copper phthalocyanine). The composition of the present invention forms optically clear, hard, and non-delaminating coatings for a variety of substrates such as paper, metal, plastic, and glass.

[0056] Examples

[0057] Intermediate Example 1 - Preparation of Compounds of Formula la and lb

[0058] l,3,5-Triallyl-l,3,5-triazine-2,4,6(lH,3H,5H)-trione (TTT, 37.4 g) was added to an oven-dried 250 mL 3 -neck round bottom flask containing a magnetic stir bar and equipped with an addition funnel, thermocouple, and glass stopper. l,l,3,3-Tetramethyl-l-(2- ( trimethoxy silyl)ethyl)disiloxane (TTDS, 31.8 g) was added to the addition funnel, and the flask was heated to 60 °C with stirring. Once the contents of the flask reached 58 °C, addition of TTDS was added over 2 min with concomitant addition of Karstedt's catalyst (5 ppm). The mixture was allowed to stir with heating for 45 min. Next, TTDS (31.8 g) was added to the addition funnel; this material was added to the flask over 3 min with concomitant addition of Karstedt’s catalyst (5 ppm). The reaction was allowed to stir with heating for 30 min. Next, the temperature was increased to 80 °C, and the reaction allowed to stir with heating for 18 h. The material was collected as a colorless, transparent liquid.I3C NMR and29Si NMR spectroscopic data were consistent with the formation of structures of Formulas la and lb. Prep HPLC was used to verify the product distribution: Formula la = 38.0 wt%; Formula lb = 38.5 wt%, TTT = 6.6 wt%; and tri-TTDS functionalized isocyanurate = 16.9 wt%.

[0059] Examples

[0060] In the following examples, trimethyl(methylcyclopentadienyl)platinum (IV) is a solution of 1 part-by-weight (pbw) trimethyl(methylcyclopentadienyl)platinum (IV) diluted with 99 pbw of methyltrimethoxysilane; and Karstedt’s catalyst (platinum(O) 1,3-diethenyl-l, 1,3,3-tetramethyldisiloxane in 70 wt% isopropanol) is a solution of 0.5 pbw of Karstedt’s catalyst diluted with 99.5 pbw methyltrimethoxy silane.

[0061] Example 1 - Preparation and UV-Curing of a Resin Composition with Trimethyl(methylcyclopentadienyl)platinum (IV) Catalyst and Adhesion Promoter

[0062] ^Vij-jPh^p^Vi 649 pbw), polymethyphenylsiloxane resin (MMePhV1o.23TPho.77, 67.75 pbw); 1, 1,5,5-tetramethyl-3,3-diphenyltrisiloxane (20.76 pbw); methyl(tris(l,l-dimethyl-2-propynyl) oxy) silane (0.0008 pbw); and Intermediate Example 1 (1 pbw) adhesion promoter were added to a vessel and mixed at 1,500 rpm for 2 min, followed by addition of Reolosil DM-30S fumed silica filler (3 pbw). Mixing was continued at 2,000 rpm for 2 min, then hand-mixed, then mixed again at 2,000 rpm for 2 min. Then, trimethyl (methylcyclopentadienyl )platinum (IV) (1 pbw) was added to the blend and mixing was continued at 1,500 rpm for an additional 2 min. The sample was cured by LED UV (Firejet FJ800) equipment with 365 nm and energy 5,000 mJ / cm2dosage of UVA; cure was completed by heating the sample to 70 °C for 30 min.

[0063] Example 2 - Preparation and Heat-Curing of a Resin Composition with Karstedt’s Catalyst and Adhesion Promoter

[0064] MV1DPh23MV1(6.49 pbw), polymethyphenylsiloxane resin (MMePhV1o.23TPho.77, 68.49 pbw); 1, 1,5,5-tetramethyl-3,3-diphenyltrisiloxane (20.98 pbw); methyl(tris(l,l-dimethyl-2-propynyl) oxy) silane (0.0008 pbw); and Intermediate Example 1 (1 pbw) adhesion promoter were added to a vessel and mixed at 1,500 rpm for 2 min, followed by addition of Reolosil DM-30S fumed silica filler (3 pbw). Mixing was continued at 2,000 rpm for 2 min, then hand-mixed, then mixed again at 2,000 rpm for 2 min. Then, Karstedt’s catalyst (0.04 pbw) was added to the blend and mixing was continued at 1,500 rpm for an additional 2 min. The sample was cured at 150 °C for 1 h. Comparative Example 1 - Preparation and UV-Curing of a Resin Composition with Trimethyl(methylcyclopentadienyl)platinum (IV) Catalyst Without Adhesion Promoter MVlDPh23MV1(6.49 pbw), polymethyphenylsiloxane resin (MMePhV1o.23TPho.77, 68.85 pbw); 1, 1,5,5-tetramethyl-3,3-diphenyltrisiloxane (20.66 pbw); and methyl(tris( 1,1 -dime thyl-2-propynyl) oxy) silane (0.0008 pbw) were added to a vessel and mixed at 1,500 rpm for 2 min, followed by addition of Reolosil DM-30S fumed silica filler (3 pbw). Mixing was continued at 2,000 rpm for 2 min, then hand-mixed, then mixed again at 2,000 rpm for 2 min. Then,

[0065] trimethyl (methylcyclopentadienyl )platinum (IV) (1 pbw) was added to the blend and mixing was continued at 1,500 rpm for an additional 2 min. The sample was cured by LED UV (Firejet FJ800) equipment with 365 nm and energy 5,000 mJ / cm2dosage of UVA; cure was completed by heating the sample to 70 °C for 30 min.

[0066] Comparative Example 2 - Preparation and Heat-Curing of a Resin Composition with Platinum, 1,3-Diethenyl-1,L3,3-Tetramethyldisiloxane Catalyst Without Adhesion Promoter MV1DPh23MV1(6.49 pbw), polymethyphenylsiloxane resin (MMePhV1o.23TPho.77, 69.59 pbw); 1, 1,5,5-tetramethyl-3,3-diphenyltrisiloxane (20.87 pbw) and methyl(tris(l,l-dimethyl-2-propynyl) oxy) silane (0.0008 pbw) were added to a vessel and mixed at 1,500 rpm for 2 min, followed by addition of Reolosil DM-30S fumed silica filler (3 pbw). Mixing was continued at 2,000 rpm for 2 min, then hand-mixed, then mixed again at 2,000 rpm for 2 min. Then, Karstedt’s catalyst (0.04 pbw) was added to the blend and mixing was continued at 1,500 rpm for an additional 2 min. The sample was cured at 150 °C for 1 h.

[0067] Peel Strength Testing Procedure

[0068] Two thermoplastic Ultradur B 4300 G4 Polybutylene Terephthalate 25 -mm x 100-mm substrates with a thickness of 3 mm were cleaned with isopropanol and dried for 18 h at 120 °C. The thermoplastic substrates were preheated at 150 °C for 5 min prior to overmolding with the LSR. Substrates were overmolded with a 3-mm layer of the LSR formulation, and compression molded for 5 min at 150 °C at a pressure of 300 bar.

[0069] Adhesion was tested in a 90° peel test using a floating roller device as described in DIN EN ISO 22631 (“Adhesives - Test method for adhesives for floor and wall coverings”). A tensile tester was used at a pulling speed of 100 mm / min.

[0070] Crosshatch Procedure

[0071] ASTM D3359 was used to measure the area removed on a coated glass slide. The coated surface was etched in a crosshatched fashion and tested. The crosshatch test classifications are illustrated in Table 1.

[0072] Table 1 - Crosshatch Test Classifications

[0073] Classification % Area Removed

[0074] 0B > 65%

[0075] IB 35-65%

[0076] 2B 15-35%

[0077] 3B 5-15%

[0078] 4B < 5%

[0079] 5B 0%

[0080]

[0081] Adhesion Lap Shear Testing

[0082] Lap shear testing was carried out using an Instron 3366 mechanical testing system. The cured samples (10-mm thick) were sandwiched between two 0.5-mm thick glass or aluminum (Al) substrates; each substrate was pulled and pushed parallel to the sample until breakage occurred due to adhesive failure (AF), cohesive failure (CF), or substrate failure (SF). The results of the adhesion lap shear, crosshatch testing, and failure modes of the samples are illustrated in Table 2. Table 2 - Adhesion Lap Shear, Crosshatch, and Failure Mode of Cured Coated Substrates Ex. 1 Ex. 2 Comp. Ex. 1 Comp. Ex 2 Adhesion lap shear Glass (MPa) > 5.50 > 5.50 3.86 > 5.50 Failure mode on Glass SF SF AF SF Adhesion lap shear on Al (MPa) 4.43 10.12 2.49 1.70

[0083] Failure mode on Al CF CF AF AF Crosshatch Classification 5B 5B 0B 0B

[0084]

[0085] The data show that the samples with Intermediate Example 1 as the adhesion promoter met all the desired criteria of high adhesion lap shear strength, cohesive failure, and excellent crosshatch properties for the substrates tested.

Claims

Claims:

1. A composition comprising:a) one or more compounds of Formula 1 :Si(OMe)3Formula 1b) a divinyl-terminated polyphenylsiloxane;c) a vinyl-terminated polyphenylsiloxane resin;d) a hydrogenphenylsiloxane; ande) a hydrosilylation catalyst;where X is a double bond or -CH2CH2-Si(CH3)2OSi(CH3)2-CH2CH2-Si(OCH3)3.

2. The composition of Claim 1 wherein, based on the weight of the composition, the concentration of the compound of Formula 1 is in the range of from 0.1 to 5 weight percent; the concentration of the divinyl-terminated polyphenylsiloxane is in the range of from 1 to 30 weight percent; the concentration of the vinyl-terminated polyphenylsiloxane resin is in the range of from 50 to 80 weight percent; and the concentration of the hydrogenphenylsiloxane is in the range of from 10 to 30 weight percent.

3. The composition of Claim 2 wherein the divinyl-terminated polyphenyl siloxane is a compound of the following formula:where Ph is phenyl, each R' is independently methyl or phenyl; and n is from 5 to 200.

4. The composition of Claim 3 where the vinyl-terminated polyphenyl siloxane resin is the reaction product of a tri-Ci-Ce-alkoxyphenylsilane and a divinyl-terminated polyphenylsiloxane of the following formula:where n' is 1, and each R' is independently methyl or phenyl.

5. The composition of Claim 4 wherein the hydrogenphenylsiloxane is a compound of the following formula:where each R is independently Ci-Ce-alkyl or phenyl; and m is from 1 to 10.

6. The composition of any of Claims 1 to 5 wherein the one or more compounds of Formula 1 is a mixture of compounds of Formula la and Formula lb:Formula la Formula lb7. The composition of Claim 6 wherein the vinyl-terminated polyphenylsiloxane resin is of the form MMePhV1aTPhb, where a and b are mole fractions, where mole fraction “a” is in the range of from 0.10 to 0.40 and mole fraction “b” is in the range of from 0.60 to 0.90.

8. The composition of Claim 2 wherein the hydrosilylation catalyst is a platinum catalyst.

9. The composition of Claim 7 where the platinum catalyst is platinum(II) acetoacetonate, platinum(O) l,3-divinyl-l,l,3,3-tetramethyldisiloxane complex or trimethyl(methylcyclopentadienyl)platinum (IV) .

10. The composition of Claim 8 which further comprises an inhibitor for the platinum catalyst.

11. The composition of Claim 9 which further comprises phenylbutynol or methyl(tris(l,l-dimethyl-2-propynyl) oxy) silane.

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