LOW TEMPERATURE CURABLE ADDITION POLYMERS FROM VINYL ARYLCYCLOBUTENE-CONTAINING MONOMERS AND METHODS FOR MAKING THE SAME

Abstract

The present invention provides a low temperature polymerizing and curing polymer composition comprising, in copolymerized form, one or more addition polymerizable arylcyclobutene monomers A having as a cyclobutene ring substituent one or more groups chosen from alkyl; heteroatom containing alkyl; aryl; heteroatom containing aryl; or heteroatom containing aryloxy, one or more aromatic addition polymerizable second monomers, and one or more other addition polymerizable monomers chosen from an addition polymerizable nitrogen heterocycle containing third monomer, an addition polymerizable fourth monomer, or, preferably, both of the one or more third monomers and the one or more fourth monomers. The polymer compositions find use in making films or coatings for use in electronics applications.

Claims

1. A polymer composition comprising, in copolymerized form, a monomer mixture of one or more addition polymerizable arylcyclobutene-containing monomers A having as a cyclobutene ring substituent one or more groups chosen from alkyl; heteroatom containing alkyl; aryl; heteroatom containing aryl; or heteroatom containing aryloxy, one or more aromatic addition polymerizable second monomers, and one or more other addition polymerizable monomers chosen from an addition polymerizable nitrogen heterocycle containing third monomer, an addition polymerizable fourth monomer, or both of the one or more third monomers and the one or more fourth monomers.

2. The polymer composition as claimed in claim 1, wherein the polymer composition comprises the at least one polymer of, in copolymerized form, a monomer mixture of one or more addition polymerizable arylcyclobutene-containing monomers A having as a cyclobutene ring substituent one or more groups chosen from alkyl and aryl and the polymer compositions further comprise an addition polymerizable crosslinker monomer containing two or more allyl groups.

3. The polymer composition as claimed in claim 1, wherein the polymer composition comprises, in copolymerized form, the monomer mixture wherein the one or more arylcyclobutene-containing monomers A has Structure A-1 or a Structure A-2: ##STR00002## wherein, K.sub.1 is a divalent heteroatom containing hydrocarbon group having from 1 to 36 carbon atoms; a divalent hydrocarbon group having from 1 to 36 carbon atoms; a cyano group; a carbonyl group; an ester group (COO); a carboxyl group (OOC); or is a divalent heteroatom group; K.sub.2 is a covalent bond or a divalent group chosen from a C.sub.1 to C.sub.6 alkyl substituted or unsubstituted divalent aryl group; a C.sub.1-C.sub.6 alkyl substituted or unsubstituted divalent hydrocarbon group; a divalent C.sub.1 to 030 alkylene group; a divalent heteroatom containing hydrocarbon group; an ether group (O); a thioether group (S), a carbonyl group; an ester group (COO); a carboxyl group (OOC) or a cyano group; M is a divalent aromatic group chosen from a C.sub.1 to C.sub.6 alkyl substituted or unsubstituted aromatic radical group, or a C.sub.1 to C.sub.6 alkyl substituted or unsubstituted divalent heteroaromatic radical group; L.sub.1 is a covalent bond or is a hydrocarbon linking group having a valence of x+1; R.sub.1 through R.sub.6 are each independently selected from a monovalent group chosen from hydrogen, deuterium, halogen, hydroxyl a C.sub.1 to C.sub.6 alkyl group, a C.sub.1 to C.sub.6 alkoxy group, a C.sub.1 to C.sub.6 alkyl substituted hydrocarbon group, a heteroatom containing hydrocarbon group, a C.sub.1 to C.sub.6 alkyl substituted heterohydrocarbon group, a cyano group, an hydroxyl group, a monovalent aryl group, a C.sub.1 to C.sub.6 alkyl substituted aryl group, a heteroaryl group, or a C.sub.1 to C.sub.6 alkyl substituted heteroaryl group; and, x and y are each independently an integer from 1 to 5 wherein y is 1 when L.sub.1 is a covalent bond; wherein, when the one or more arylcyclobutene-containing monomers A has the structure A-1, each of R.sub.1, R.sub.2 and R.sub.3 is a hydrogen; and, further wherein, when the one or more arylcyclobutene-containing monomers A has the structure A-2; and at least one of R.sub.1, R.sub.2 and R.sub.3 is chosen from a C.sub.1 to C.sub.6 alkyl group; a C.sub.1 to C.sub.6 alkoxy group; a C.sub.1 to C.sub.6 alkyl substituted hydrocarbon group having from 5 to 36 carbon atoms; a heteroatom containing hydrocarbon group; a C.sub.1 to C.sub.6 alkyl substituted heterohydrocarbon group; a cyano group; an aryl group; a C.sub.1 to C.sub.6 alkyl substituted aryl group; a heteroaryl group; or a C.sub.1 to C.sub.6 alkyl substituted heteroaryl group.

4. The polymer composition as claimed in claim 3, wherein the one or more arylcyclobutene-containing monomers A having the Structure A-1, wherein K is a an ether group, a thioether group, or a C.sub.1 to C.sub.6 alkyl substituted or unsubstituted divalent O-heteroaryl group or S-heteroaryl group having from 5 to 36 carbons.

5. The polymer composition as claimed in claim 3, wherein in the one or arylcyclobutene-containing monomers A, x and y are each independently an integer of from 1 to 2.

6. The polymer composition as claimed in claim 3, wherein the one or more arylcyclobutene-containing monomers A comprise an -vinyl phenoxy benzocyclobutene, -vinyl methoxy benzocyclobutene, -vinyl phenyl BCB or an -vinyl hydroxynaphthalene BCB monomer of structure A-1, a vinyl -alkoxy benzocyclobutene, a vinyl -phenoxy benzocyclobutene, or a vinyl -C.sub.1 to C.sub.6 alkyl benzocyclobutene monomer of structure A-2.

7. The polymer composition as claimed in claim 1, comprising a polymer of, in copolymerized form, a monomer mixture of the one or more addition polymerizable arylcyclobutene-containing monomers A, the one or more aromatic addition polymerizable second monomers chosen from styrene, -methyl styrene, -myrcene, allyloxystyrene, allyl terminated polyarylene ethers or maleimide terminated polyarylene ethers; and the nitrogen heterocycle containing addition polymerizable third monomer.

8. The polymer composition as claimed in claim 1, comprising a polymer of, in copolymerized form, a monomer mixture of the one or more addition polymerizable arylcyclobutene-containing monomers A; the one or more aromatic addition polymerizable second monomers; and the one or more nitrogen heterocycle containing addition polymerizable third monomer chosen from N-vinyl pyridine, N-vinyl imidazole or other vinyl pyridine isomers or two or more addition polymerizable group containing nitrogen heterocycle containing third monomers.

9. The polymer composition as claimed in claim 1, comprising a polymer of, in copolymerized form, a monomer mixture od from 10 to 90 wt. % of the one or more arylcyclobutene-containing monomers A; from 5 to 70 wt. % of the one or more aromatic addition polymerizable second monomers; from 5 to 40 wt. % of the one or more other addition polymerizable monomers which is the one or more nitrogen heterocycle containing addition polymerizable third monomers, the one or more addition polymerizable fourth monomers, or both the third monomer and the fourth monomer, all weights based on the total solids weight of monomers used to make the copolymer with all monomer wt. % s adding to 100%.

10. The polymer composition as claimed in claim 1, comprising a polymer of, in copolymerized form, a monomer mixture of the one or more addition polymerizable arylcyclobutene-containing monomers A, the one or more aromatic addition polymerizable second monomers, and the one or more other addition polymerizable monomers which is one or more addition polymerizable fourth monomers chosen from acrylates or methacrylates; maleimides and bis-maleimides; cyclic anhydrides; (meth)acrylates for improving adhesion promotion; allyl group containing monomers for adhesion promotion; linear and branched alkenes; cyclic olefins; and fourth monomers containing a second dienophile or addition polymerizable group.

11. A method of making thin films or coatings on a substrate comprise depositing and evaporating, or coating on a substrate the polymer composition as claimed in claim 1.

Description

EXAMPLES

[0107] The present invention will now be described in detail in the following, non-limiting Examples:

[0108] Unless otherwise stated all temperatures are room temperature (21-23 C.) and all pressures are atmospheric pressure (760 mm Hg or 101 kPa).

[0109] Notwithstanding other raw materials disclosed below, the following raw materials were used in the Examples:

[0110] A-POSS: multifunctional acrylate with an inorganic silsesquioxane at the core and organic acrylopropyl groups attached at the corners of the cage (CAS: 1620202-27-8, Hybrid Plastics

[0111] BCB: benzocyclobutene;

[0112] BPO: Benzoyl peroxide;

[0113] BMI: Bismaleimide (unless otherwise indicated, FW 358.35);

[0114] BMI-TMH: bis-maleimide of 2,2,4-trimethyl hexane;

[0115] CL A: propoxylated trimethylolpropane triacrylate (SR492, Sartomer, Exton, Pa.);

[0116] CL B: tricyclodecanedimethanol diacrylate (SR833s, Sartomer);

[0117] DAAM: Diacetone acrylamide (2-Propenamide, N-(1,1-dimethyl-3-oxobutyl)-;

[0118] DVS or DVS-bis-BCB: (divinyl siloxane containing bisbenzocyclobutene monomer);

[0119] H126: Di-allyl bisphenol A, aka benzene, 1,1-(1-methylethylidene)bis[4-(2-propen-1-yloxy)-] (CAS 3739-67-1);

[0120] Irganox 1010: Pentaerythritol tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate) antioxidant (BASF, Ludwigshafen, DE);

[0121] MBA: 3-methoxy butylacetate solvent;

[0122] PET: poly(ethylene terephthalate); and,

[0123] MI: maleimide;

[0124] TAIC: triallyl isocyanurate, 1,3,5-Triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-tri-2-propen-1-yl- (CAS 1025-15-6, Evonik, Essen, Del.);

[0125] TMPTA: trimethylolpropane triacrylate (Sartomer. CAS 15625-89-5); and,

[0126] V601: A diazo radical initiator, dimethyl 2,2-azobis(2-methylpropionate) (CAS No 2589-57-3, Wako Chemical, Richmond, Va.).

[0127] The materials were analyzed in various disclosed ways, including, as follows:

[0128] Mole Ratio Calculation:

[0129] Moles of second, third and fourth monomers to moles of arylcyclobutene-containing monomer A was calculated from the starting number of moles of arylcyclobutene monomer. The residual exotherm from B-staging was measured in J/g and compared to the total enthalpy in the bis-arylcyclobutene monomer (in J/g, for DVS it is 800 J/g, corresponding to 156 J/mmol of BCB). The ratio of residual exotherm to enthalpy gave a number of mmols of arylcyclobutene monomer per gram of solids; this was multiplied by the total mass in grams of solid, to give total mmols of arylcyclobutene monomer. This was compared to number of mmoles of other monomers added to give the mole ratio.

Synthesis Example 1: Preparation of Low Curing BCB Polymer A

[0130] In this example, in a 100 ml EasyMax reactor (Mettler, Toledo, Columbia, Md.) with a polytetraflouroethylene (Teflon polymer, Dupont, Wilmington, Del.) coated thermocouple and overhead mechanical stirring, was charged a heel of cyclopentanone (4.77 g) solvent and 4-vinyl pyridine (1.10 g). The reactor was cooled to 10 C. and purged with nitrogen for 20 minutes. In a separate 50 ml pear shaped round bottom flask, styrene (5.99 g), n-butyl acrylate (1.34 g), vinyl phenoxy BCB (6.11 g), and V601 (80 mg) were added, capped with a rubber septum and purged with nitrogen for 20 minutes. The resulting solution was drawn into a 50 ml syringe, and secured into a syringe pump. The reactor was heated to the reaction temperature (67 C.), and then the reaction solution was added via syringe pump at a rate of 4 ml/h. After 5 h from the start of the addition, a chase of V601 initiator in 2-pentanone (40 mg in 4.83 g) was added via syringe at a right of 2 ml/h. The reaction continued for a total of 20 h then was cooled to room temperature and precipitated into methanol for use. GPC: Mn=10.5 k, Mw=35.9 k PDI=3.41.

Synthesis Example 2: Preparation of Low Curing BCB Polymer B

[0131] A polymer was made in the manner disclosed above for Synthesis Example 1, except that a heel of butyl acetate (13.0 g) solvent was charged. Further, to a separate 50 ml pear shaped round bottom flask were added, styrene (12.99 g), n-butyl acrylate (2.91 g), -methyl vinyl BCB (11.44 g), and benzoyl peroxide (120 mg). The reactor was heated to a reaction temperature of 100 C. After 24 h from the start of the addition, a chase of benzoyl peroxide initiator in n-butyl acetate (40 mg in 7.71 g) was added via syringe at a right of 2 ml/h. The polymer was poured into a jar for use. GPC: Mn=29.9 k, Mw=109.4 k PDI=3.65.

[0132] Polymer Testing:

[0133] The polymer of Example 1, the crosslinker and other materials, as indicated in Table 1, below, were combined and mixed in a 20 ml vial, draw coated on glass then peeled off the glass and placed into a DSC pan for analysis.

TABLE-US-00001 TABLE 1 Curable Polymer Compositions Components Ex 1 Ex 2 Ex 3 Polymer A 0.172(g) 0.155(g) Polymer B 0.725(g) Irganox.sup., 2 1010 0.020(g) 0.020(g) TAIC 0.013(g) 0.087(g) CL B.sup.3 0.022(g) 1. Units are in grams; .sup.2 BASF; * Denotes Comparative Example.

[0134] The polymer curing kinetics were evaluated via differential scanning calorimetry (TA Instruments Q2000, TA Instruments, New Castle, Del.), as disclosed below. Thermal stability was evaluated using thermogravimetric analysis (TA Instruments Q5000) under nitrogen atmosphere, as disclosed below. DSC and TGA information are presented in Table 2, below.

[0135] Differential Scanning Calorimetry (DSC):

[0136] To give a glass transition temperature (Tg) DSC was performed with a TA Instruments Q2000 DSC device. A sample was weighed out (2-10 mg) and placed in an aluminum pan. A reference pan with no sample is placed in the reference slot of the device. The samples were equilibrated at 23 C., then ramped linearly to 300 C. at a rate of 10 C./minute under a nitrogen flow of 50 ml/min. The reported Tg is the inflection point of the resulting DSC curve.

[0137] Thermal stability was tested by running TGA analysis (Q500 TGA instrument, TA Instruments, New Castle, Del.). A platinum 50 L pan was tared then a polymer sample (1-10 mg) was loaded. The furnace is sealed and then the temperature is ramped from 25 C. to 600 C. at rate of 10 C./min under nitrogen atmosphere 25 ml/min gas flow.

TABLE-US-00002 TABLE 2 DSC and TGA Data Peak Onset T Peak Max T Peak Energy Example (deg C.) (deg C.) (J/g) 1 150.74 188.95 189.6 2 150.27 181.62 213 3 197.53 230.87 307.7

[0138] As shown in Table 2, above, the onset cure temperature for a polymer of a phenoxy substituted arylcyclobutene-ring containing monomer A is much lower than that for polymer of an alkyl substituted arylcyclobutene-ring containing monomer A. As shown by Example 2, curing through DSC with an acrylate crosslinker CL B in Example 2 produces a sharper DSC peak than curing with a comparable allyl crosslinker, triallyl isocyanurate and may cure slightly faster; however, the allyl crosslinker enables easier orthogonal cure via addition and ring opening together.

Synthesis Example 3: Preparation of Polymer C (Terpolymer 10% CHMA-67% Sty-23% -Methyl Vinyl BCB)

[0139] To a 100 mL EasyMax vessel equipped with septa, reflux condensor, nitrogen inlet, and overhead stirrer was added 13 g of n-butyl acetate. The solvent was flushed with nitrogen for 30 minutes, after which the solvent was heated to 100 C. Concurrently, n-butylacetate (1.12 g), styrene (15.18 g, 0.146 mol), cyclohexylmethacrylate (3.66 g, 0.022 mol), alpha methyl-vinyl-benzocyclobutene (7.22 g, 0.05 mol) and benzoyl peroxide initiator (0.17 g, 0.7 mmol, Sigma Aldrich, St. Louis, Mo.) were flushed with nitrogen for 30 minutes and added into a 100 mL Hamilton gastight syringe (Hamilton Company, Reno, Nev.). Once the internal temperature of the solvent had reached and stabilized at 108 C., and the stir rate was set to 250 rpm the monomer feed was initiated at a rate of 20 mL per hour. At the completion of the addition, a small exotherm was observed. The reaction was allowed to stir for 24 hours, after which was added a nitrogen flushed solution of benzoyl peroxide in n-butyl acetate (0.06 g, 0.239 mmol) and n-butylacetate (7.39 g). This chase was added at a rate of 20 mL per hour and the reaction was allowed to continue for 10 hours. After this time, the polymer was cooled to room temperature and transferred into a pre-tarred glass bottle and kept at 55% solids. Polymer C was kept in solution. Polymer characterization included GPC (147.5 k MW, 28.3 k Mn, 5.2 PDI)

Comparative Example 3: Preparation of Comparative Polymer D (Terpolymer 10% CHMA-67% Sty-23% Vinyl BCB)

[0140] The polymer was synthesized as in Synthesis Example 3, above, but using vinyl BCB in place of a-methyl Vinyl BCB.

[0141] Solutions of the indicated polymer were cast onto a glass plate and drawn into films using a 76.2 micron (3 mil) steel draw down bar. Films were soft baked in a convection oven set at 120 C. for 10 min to remove solvent, and the polymer was collected by scraping the material off the plate using a razor blade. Cure data was collected using a Q2000 series DSC (TA Instruments). Cure point was determined by ramping 5 mg samples enclosed in an aluminum pan from 30 C. to 350 C. at a ramp rate of 10 C./min, while cure amount or degree was determined by isothermally holding samples at the indicated temperature for the required amount of time before ramping the temperature from 30 C. to 350 C. to determine any residual unreacted BCB units. Note that peak onset is defined as the intersection of two tangent lines on a DSC curve. Data are presented in Table 3, below.

TABLE-US-00003 TABLE 3 DSC Cure Onset Peak Peak Example Polymer Onset Maximum 4 C: -MevBCB 195 263 Sty polymer 5* D: vBCB Sty 215 269 polymer *Denotes comparative Example

[0142] As shown in Table 3, above, the a-Me vinyl BCB-styrene Polymer C of Synthesis Example 3 reacts at lower temperatures than the comparative Example 3 styrene Polymer D comprising, in copolymerized form, a non-methylated vinyl BCB monomer. Although the a-Me vBCB ring opens at a lower temperature, the curing end point (peak max) was similar to that of the comparative polymer D made using vBCB because the polymers had a similar BCB level.

[0143] Additional data from the DSC analysis are presented in Table 4, below.

TABLE-US-00004 TABLE 4 DSC Cure Timing Cure T Cure Tg Peak Polymer ( C.) Time (h) ( C.) Temp ( C.) Area (J/g) Conv % C control 0 68.8 265.7 203.5 0 C 180 1 115.8 269.2 142.6 29.9 C 180 2 121.7 270.5 137 32.7 C 200 1 138.1 274.9 90.9 55.3 C 200 2 147.4 277.2 80.2 60.6 C control complete 186.8 0 100 cure D* control 0 76.9 269.2 178.6 0 D* 180 1 104.3 274.4 164.6 7.8 D* 180 2 109.6 276.6 150.5 15.7 D* 200 1 119.3 281.1 128 28.3 D* 200 2 127 283.4 114 36.2 D* control complete 186 0 100 cure *Denotes comparative Example

[0144] Polymer C of the present invention, made using -Me vBCB ring opens at a lower temperature than Comparative Polymer D, made using v BCB. Further, Polymer C, exhibited a dramatically increased conversion % when compared to the Comparative Polymer D made using a non-methylated vBCB.

Example 6: Cure Increase Using Different Crosslinkers

[0145] The formulations indicated in Table 5, below, were made by adding the indicated materials to a small cup and then blending for 30 seconds at 3500 rpm using a FlakTec speed mixer (FlackTek Inc, Landrum, S.C.), including a crosslinking monomer. Results are shown in Tables 6, 7, and 8, below.

TABLE-US-00005 TABLE 5.sup.1 Curable Formulations Example 6-1 6-2 6-3 Materials BMI- TAIC SR492 TMH Polymer C 0.37 0.44 0.37 BMI-TMH 0.071 TAIC 0.043 CL A 0.070 Butyl Acetate 0.056 0.018 0.055 .sup.1Units are in grams.

TABLE-US-00006 TABLE 6 DSC Cure of Materials Peak Peak Onset Temp Temp T 1 Max 1 Area 1 Onset T 2 Max 2 Area 2 Material ( C.) ( C.) (J/g) ( C.) ( C.) (J/g) Polymer C + 118.2 147 117.6 210.8 261 71.2 CL A CL A Only 157 197 362.2 N/A N/A N/A Polymer C 195.2 264.5 148 N/A N/A N/A Polymer C 195.5 264.54 147 Polymer C + 197.78 232.41 319.4 TAIC TAIC 250.37 275.05 109.1 Polymer C 195.5 264.54 147 Polymer C + 197.96 231.62 289.9 BMI-TMH BMI-TMH 238.36 264.49 73.24

[0146] As shown in Table 6, above, the combination of crosslinker A and inventive Polymer C cured at a dramatically lower temperature than either the crosslinker or polymer alone. This indicates separate curing of each. However, the analysis in the case of TAIC or BMI-TMH indicates greater cure energy from their combination with the polymer, indicating ring opening cure.

[0147] In the following 2 tables, DSC analysis was modified as the temperature was held at the indicated cure temperature.

TABLE-US-00007 TABLE 7 Isothermal Hold Cure Peak Cure T Time Onset Temp Area Conv, Material ( C.) (h) T ( C.) Max ( C.) (J/g) % Polymer C polymer 0 68.8 265.7 203.5 0 only Polymer C + 180 2 219.3 268.74 84.85 58.3 CL A Polymer C + 200 2 237.59 275.81 46.82 77.0 CL A

[0148] As shown in Table 7, above, CL A does not incorporate into the polymer network by ring opening, and instead cures or converts to cured material separately. Addition crosslinking took place at below 200 C.

TABLE-US-00008 TABLE 8 DSC Cure Timing Cure T Cure Tg Peak Temp Area Conv Material ( C.) Time (h) ( C.) ( C.) (J/g) % Polymer C control 0 68.8 265.7 203.5 0 Polymer C 180 2 121.7 270.5 137 32.7 Polymer C 200 2 147.4 277.2 80.2 60.6 Polymer C + control 0 42.2 232 335.3 0 TAIC Polymer 180 2 142.5 234.4 63.5 81.1 C + TAIC Polymer control 0 N/A 231.7 307.4 0 C + BMI- TMH Polymer 200 2 181.3 264.9 1.8 99.5 C + TAIC Polymer 180 2 126.3 233.8 65.1 78.8 C + BMI- TMH Polymer 200 2 161.9 264.5 3.5 98.9 C + BMI- TMH *Denotes comparative Example

[0149] The area under the largest peaks as well as the temperature corresponding to the peak and then diminishing area in the above Table shows that the TAIC or the BMI-TMH crosslinker react with polymer in a single ring opening, addition and overall complete cure at a significantly reduced cure temperature. The above table indicates complete cure within 2 hours as shown by Conv %.