Curable acrylate or methacrylate compositions

Abstract

A curable composition based on a curable acrylate or methacrylate component; an organoborane initiator component; a vinyl ether component; and an activator for the organoborane component. The composition exhibits good storage stability and good bonding properties when used to bond low surface energy substrates.

Claims

1. A curable composition comprising: a curable (meth)acrylate component comprising the combination of at least two (meth)acrylate monomers, at least one of which is tetrahydrofurfuryl (meth)acrylate; an organoborane:triethylene diamine complex; an initiator component for the organoborane component comprising a vinyl ether component; and an activator for the organoborane component, wherein the vinyl ether component is present in an amount of 0.25 to 5% weight based on the total composition and is a member selected from the group consisting of bis[4-(vinyloxy)butyl]isophthalate, ethyl vinyl ether, n-butyl vinyl ether, iso-butyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, 1,4-cyclohexanedimethanol divinyl ether, 1,4-cyclohexanedimethanol mono vinyl ether, 2-ethylhexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 1,4-butanediol divinyl ether, diethyleneglycol divinyl ether, triethyleneglycol divinyl ether, hydroxybutyl vinyl ether, ##STR00004## and combinations thereof, wherein the curable composition is in a two-part form with the curable (meth)acrylate component present in at least one of Part A or Part B, wherein Part A comprises the organoborane:triethylene diamine complex and the vinyl ether initiator component; and Part B comprises the activator for the organoborane component and wherein the curable composition is substantially free of added anti-oxidants, free radical stabilizers or organo aluminum compounds.

2. A composition according to claim 1 wherein the organoborane:triethylene diamine complex is present in an amount from about 0.1 to about 10% weight percentage based on the total weight of the composition.

3. A composition according to claim 1 wherein the activator for the organoborane compound is selected from the group consisting of Lewis acids, carboxylic acids, phosphoric acids, anhydrides and isocyanates and combinations thereof.

4. A composition according to claim 1 wherein the activator is present in an amount from about 1 to about 40% weight percentage based on the total weight of the composition.

5. A composition according to claim 1 wherein the (meth)acrylate component is present in an amount from about 10 to about 95% weight percentage based on the total weight of the composition.

6. A composition according to claim 1 wherein the second part comprises a curable maleate, fumarate or maleimide component.

7. A composition according to claim 6 wherein the maleate, fumarate or maleimide component is present in an amount from about 1 to about 20% weight percentage based on the total weight of the composition.

8. A composition according to claim 1 further comprising a toughener component.

9. A composition according to claim 8 wherein the toughener component is present in an amount from about 5 to about 50% weight percentage based on the total weight of the composition.

10. A curable composition consisting of: a curable (meth)acrylate component comprising the combination of at least two (meth)acrylate monomers, at least one of which is tetrahydrofurfuryl (meth)acrylate; an organoborane:triethylene diamine complex; an initiator component for the organoborane component comprising a vinyl ether component; and an activator for the organoborane component, wherein the vinyl ether component is present in an amount of 0.25 to 5% weight based on the total composition and is a member selected from the group consisting of bis[4-(vinyloxy)butyl]isophthalate, ethyl vinyl ether, n-butyl vinyl ether, iso-butyl vinyl ether, t-butyl vinyl ether, cyclohexyl vinyl ether, 1,4-cyclohexanedimethanol divinyl ether, 1,4-cyclohexanedimethanol mono vinyl ether, 2-ethylhexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 1,4-butanediol divinyl ether, diethyleneglycol divinyl ether, triethyleneglycol divinyl ether, hydroxybutyl vinyl ether, ##STR00005## and combinations thereof, wherein the curable composition is in a two-part form with the curable (meth)acrylate component present in at least one of Part A or Part B, wherein Part A comprises the organoborane:triethylene diamine complex and the vinyl ether initiator component; and Part B comprises the activator for the organoborane component and wherein the curable composition is substantially free of added anti-oxidants, free radical stabilizers or organo aluminum compounds.

Description

DETAILED DESCRIPTION

(1) The invention relates to a curable composition and desirably one in the form of a two part polymerisable composition. Often a two part composition is referred to as having a “Part A” and a “Part B”. Part A may include an organoborane initiator, preferably a trialkylborane:amine complex and a vinyl ether monomer (mono- and/or di-functional). Methacrylate or acrylate esters (both mono- and/or multi-functional), polymeric tougheners, silicas and other rheology modifiers are optionally included.

(2) Part B contains methacrylate or acrylate esters (both mono- and/or multi-functional) and preferably compounds containing malaeic and/or fumarate functionality. An activator for the organoborane compound must also be present and can be chosen (but not limited to) from Lewis acids, carboxylic acids, phosphoric acids, anhydrides and isocyanates. Polymeric tougheners, silicas and other rheology modifiers are optionally included.

(3) Part A and B were prepared in 500 g quantities by mixing the components using a static mixer, mixed with an overhead stirrer.

(4) The components were then stored separately in a two part cartridge, which can dispense the parts and allow for mixing, for example through a static mixer, before application to a substrate. The components can be mixed in ratios from 1:1 to 10:1.

(5) In the Examples below Parts A and B were mixed and dispensed through a cartridge fitted with a static mixer and applied to one lap shear covering the area up to 0.5″ inches.sup.2 (12.7 mm.sup.2) which was then joined to another and clamped for 24 h at room temperature. Tensile bond strengths were determined using the following test method: the test method was based on ASTM D 1002-05. The lap shears measured 1″×4″ (25.4 mm×101.6 mm) in dimensions and the joined lap shears overlapped at a 0.5″ (12.7 mm) mark and were clamped with Hargrave No. 1 clamps. The bonded lap shears were tested using an Instron™ 5567A Materials testing System. The cross-head speed was 6 mm/min.

(6) Heat ageing was done by packing the parts into two-part cartridges and heating at 35° C. in an oven. The effect of the heat ageing was compared by comparison of retention of lap shear tensile strength over time (using test method described above), or noting when the samples could not be dispensed from the cartridges due to gelation or hardening of the compositions.

EXAMPLE 1

(7) 1:1 mix ratio formulation containing triethyleneglycol divinyl ether and heat aging data

(8) TABLE-US-00001 wt. % Part A Triethyleneglycol divinyl ether 10 Tetrahydrofurylmethacrylate (THFMA) 61.5 Ethylhexylmethacrylate (EHMA) 6 Triethylborane triethylenediamine complex (TEB:DETA) 2.5 Kraton ™ D 1155 ES 20 (Styrene-Butadiene-Styrene block co-polymer rubber) Part B THFMA 48.98 EHMA 13 TMPTMA (trimethylolpropane trimethacrylate) 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 (Acrylonitrile-Styrene-Butadiene core shell rubber) Aerosil ™ R 972 (Hydrophilic fumed silica) 1 Iodine 0.02 PP-C PE GFPP-E Coated Weeks @ 35° C. MPa MPa Steel MPa 0 Weeks 3.48 ± 0.17 3.06 ± 0.27 5.90 ± 0.27 1 Week  3.44 ± 0.41 2.67 ± 0.79 5.16 ± 0.37 2 Weeks 3.21 ± 0.13 3.62 ± 0.57 5.32 ± 0.94 3 Weeks 3.80 ± 0.23 5.58 ± 0.39 4.47 ± 0.64 4 Weeks 2.84 ± 0.03 4.41 ± 0.79 3.60 ± 1.34 5 Weeks 2.61 ± 0.27 2.48 ± 0.27 4.70 ± 1.07 6 Weeks 2.73 ± 0.11 2.32 ± 0.30 2.91 ± 0.22 7 Weeks 3.00 ± 0.10 2.13 ± 0.01 2.82 ± 1.02 8 Weeks Part A could not be dispensed

EXAMPLE 2

(9) 1:1 mix ratio formulation containing no vinyl ether and heat aging data:

(10) TABLE-US-00002 wt. % Part A Tetrahydrofurylmethacrylate (THFMA) 71.5 Ethylhexylmethacrylate (EHMA) 6 Triethylborane triethylenedimane complex (TEB:DETA) 2.5 Kraton ™ D 1155 ES 20 (Styrene-Butadiene-Styrene block co-polymer rubber) Part B THFMA 48.98 EHMA 13 TMPTMA (trimethylolpropane trimethacrylate) 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 (Acrylonitrile-Styrene-Butadiene core shell rubber) Aerosil ™ R 972 (Hydrophilic fumed silica) 1 Iodine 0.02 PP-C PE GFPP-E Coated Weeks @ 35° C. MPa MPa Steel MPa 2 Weeks 2.26 ± 0.88 3.00 ± 0.59 5.06 ± 1.00 3 Weeks 2.92 ± 0.25 4.48 ± 0.99 4.04 ± 0.31 4 Weeks Part A Polymerised

(11) Example 2 shows that removal of the triethylenegylcol divinyl ether reduces the stability of Part A.

EXAMPLE 3

(12) 1:1 mix ratio formulation containing cyclohexanedimethanol divinyl ether and heat aging data:

(13) TABLE-US-00003 wt. % Part A Cyclohexanedimethanol divinyl ether 10 Tetrahydrofurylmethacrylate (THFMA) 61.5 Ethylhexylmethacrylate (EHMA) 6 Triethylborane triethylenediamine complex (TEB:DETA) 2.5 Kraton ™ D 1155 ES 20 (Styrene-Butadiene-Styrene block co-polymer rubber) Part B THFMA 48.98 EHMA 13 TMPTMA (trimethylolpropane trimethacrylate) 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 (Acrylonitrile-Styrene-Butadiene core shell rubber) Aerosil ™ R 972 (Hydrophilic fumed silica) 1 Iodine 0.02 PP-C PE GFPP-E Coated Weeks @ 35° C. MPa MPa Steel MPa 0 Weeks 6.99 ± 0.04 4.60 ± 1.58 3.99 ± 0.57 1 Week  6.56 ± 0.09 5.01 ± 0.40 4.16 ± 0.67 2 Weeks 5.97 ± 1.02 4.31 ± 0.71 4.32 ± 1.94 3 Weeks 5.05 ± 0.65 4.02 ± 0.65 4.38 ± 0.95 4 Weeks 5.34 ± 0.22 3.76 ± 0.32 3.98 ± 0.66 5 Weeks 5.29 ± 0.54 3.54 ± 0.75 3.46 ± 1.29 6 Weeks 5.24 ± 1.56 3.02 ± 0.33 3.42 ± 1.56 7 Weeks 5.76 ± 0.83 3.11 ± 0.04 3.01 ± 1.06 8 Weeks 3.24 ± 0.89 2.98 ± 0.51 3.68 ± 0.76

(14) Example 3 shows that similar to example 1 the divinyl ether cyclohexanedimethanol divinyl ether imparts improved stability and better performance in comparison to example 2.

EXAMPLE 4

(15) 1:1 mix ratio formulation containing n-butylvinyl ether and heat aging data:

(16) TABLE-US-00004 wt. % Part A n-Butylvinyl ether 10 Tetrahydrofurylmethacrylate (THFMA) 61.5 Ethylhexylmethacrylate (EHMA) 6 Triethylborane triethylenediamine complex (TEB:DETA) 2.5 Kraton ™ D 1155 ES 20 (Styrene-Butadiene-Styrene block co-polymer rubber) Part B THFMA 48.98 EHMA 13 TMPTMA (trimethylolpropane trimethacrylate) 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 (Acrylonitrile-Styrene-Butadiene core shell rubber) Aerosil ™ R 972 (Hydrophilic fumed silica) 1 Iodine 0.02 PP-C PE GFPP-E Coated Weeks @ 35° C. MPa MPa Steel MPa 0 Weeks 5.33 ± 1.23 5.50 ± 0.61 6.98 ± 0.47 1 Week  4.99 ± 0.80 5.32 ± 0.12 6.34 ± 1.59 2 Weeks 5.62 ± 1.45 5.07 ± 0.34 7.03 ± 0.72 3 Weeks 5.12 ± 0.12 4.51 ± 0.46 6.92 ± 1.23 4 Weeks 4.76 ± 0.33 4.01 ± 0.12 6.11 ± 2.35 5 Weeks 4.21 ± 0.65 4.26 ± 0.60 6.27 ± 2.30 6 Weeks 4.45 ± 0.71 3.32 ± 0.25 3.87 ± 2.57 7 Weeks Part A Could not be dispensed

(17) Example 4 shows that although n-butylvinyl ether imparts better stability than example 2, it does not perform as well as the divinyl ethers in examples 1 and 3.

EXAMPLE 5

(18) 1:1 mix ratio formulation containing hydroxybutyl vinyl ether and heat aging data:

(19) TABLE-US-00005 wt. % Part A n-HydroxyButylvinyl ether 10 Tetrahydrofurylmethacrylate (THFMA) 61.5 Ethylhexylmethacrylate (EHMA) 6 Triethylborane triethylenediamine complex (TEB:DETA) 2.5 Kraton ™ D 1155 ES 20 (Styrene-Butadiene-Styrene block co-polymer rubber) Part B THFMA 48.98 EHMA 13 TMPTMA (trimethylolpropane trimethacrylate) 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 (Acrylonitrile-Styrene-Butadiene core shell rubber) Aerosil ™ R 972 (Hydrophilic fumed silica) 1 Iodine 0.02 PP-C PE GFPP-E Coated Weeks @ 35° C. MPa MPa Steel MPa 0 Weeks 6.88 ± 1.07 5.34 ± 0.40 7.65 ± 0.28 1 Week  5.95 ± 0.56 5.11 ± 0.85 6.45 ± 0.77 2 Weeks 5.67 ± 0.59 5.30 ± 0.12 6.12 ± 0.53 3 Weeks 5.76 ± 0.88 5.32 ± 0.25 4.70 ± 0.46 4 Weeks Part A could not be dispensed.

(20) Example 5 also shows that the vinyl ether n-hydroxylbutylvinyl ether does not impart stability and performance as well as the divinyl ethers in examples 1 and 3.

EXAMPLE 6

(21) 10:1 Mix ratio formulation containing triethyleneglycol divinyl ether and heat aging data:

(22) TABLE-US-00006 wt. % Part A1 (1 Part) Triethyleneglycol divinyl ether 73.68 TEB:DETA 21.05 Aerosil ™) R 972 5.26 Part B (10 Parts) THFMA 50 EHMA 13 TMPTMA 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 GFPP- E PP-C PE Gel Weeks @ 35° C. Coat MPa MPa MPa Time 0 Weeks 7.76 ± 4.17 3.88 ± 0.54 5.21 ± 0.96 18 sec 1 Week  9.89 ± 0.62 6.76 ± 0.06 5.44 ± 0.62 18 sec 2 Weeks 8.61 ± 1.62 6.41 ± 0.67 5.21 ± 1.82 18 sec 3 Weeks 8.91 ± 2.09 6.20 ± 0.98 5.93 ± 0.39 18 sec 4 Weeks 6.50 ± 1.80 6.59 ± 0.66 5.52 ± 0.20 16 sec 5 Weeks 7.06 ± 0.62 5.77 ± 1.36 5.76 ± 0.53 18 sec 6 Weeks 5.58 ± 1.05 6.09 ± 0.43 4.44 ± 1.73 18 sec 7 Weeks 6.30 ± 1.37 3.90 ± 1.34 3.83 ± 0.51 18 sec 8 Weeks 6.02 ± 0.40 3.70 ± 1.04 3.53 ± 0.50 20 sec

EXAMPLE 7

(23) 10:1 Mix ratio formulation containing butanediol divinyl ether and heat aging data:

(24) TABLE-US-00007 wt. % Part A1 (1 Part) Butanediol divinyl ether 73.68 TEB:DETA 21.05 Aerosil ™ R 972 5.26 Part B (10 Parts) THFMA 50 EHMA 13 TMPTMA 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 GFPP- E PP-C PE Gel Weeks @ 35° C. Coat MPa MPa MPa Time 0 Weeks 9.19 ± 1.15 6.30 ± 0.74 6.25 ± 0.10 15 sec 1 Week  9.99 ± 2.22 6.52 ± 0.24 6.09 ± 0.04 15 sec 2 Weeks 8.54 ± 1.40 6.30 ± 1.16 3.41 ± 2.16 15 sec 3 Weeks 9.73 ± 0.32 6.92 ± 0.12 5.62 ± 0.38 15 sec 4 Weeks 6.65 ± 1.46 6.29 ± 0.11 3.38 ± 0.72 15 sec 5 Weeks 5.92 ± 0.53 5.50 ± 2.06 5.66 ± 0.53 25 ec.sup. 

EXAMPLE 8

(25) 10:1 Mix ratio formulation containing methacrylate monomer instead of vinyl ether and heat aging data:

(26) TABLE-US-00008 wt. % Part A1 (1 Part) THFMA 73.68 TEB:DETA 21.05 Aerosil ™ R 972 5.26 Part B (10 Parts) THFMA 50 EHMA 13 TMPTMA 5 mono-2-(Methacryloyloxy)ethyl maleate 12 Blendex ™ B362 20 GFPP- E PP-C PE Gel Weeks @ 35° C. Coat MPa MPa MPa Time 0 Weeks 7.24 ± 0.15 6.30 ± 0.74 5.05 ± 0.13 20 sec 1 Week  8.79 ± 2.57 5.56 ± 0.94 4.23 ± 0.34 25 sec 2 Weeks 4.54 ± 1.49 4.31 ± 1.43 2.41 ± 0.19 35 sec 3 Weeks Part A could not be dispensed

(27) Examples 6 and 7 containing divinyl ethers and borane:amine in the same part show improved stability in comparison to methacrylate ester monomer THFMA and borane:amine in the same part.

(28) The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

(29) It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.