Anaerobically curable compositions

Abstract

An anaerobically curable composition comprising an anaerobically curable component that is a combination of a solid resin component and a solid anaerobically curable monomer. A curing component for curing the anaerobically curable component is included. The composition is solid and has a melting point in the range from 30 C. to 100 C. The composition is dry to touch and can be used to form articles of manufacture such as a tape, an elongate filament, a gasket, a patch.

Claims

1. A threadlocking composition comprising: (a) an anaerobically curable component comprising an anaerobically curable monomer and an anaerobically curable resin component, wherein the anaerobically curable monomer and the anaerobically curable resin component are each a solid, each having a melting point in the range from 30 C. to 100 C.; and (b) an anaerobic curing component for curing the anaerobically curable component; wherein the anaerobically curable component is present in the composition in an amount sufficient to render the composition in flowable particulate form and has a melting point in the range from 30 C. to 100 C.

2. The composition according to claim 1 wherein the composition has a melting point from 40 C. to 100 C.

3. The composition according to claim 1 wherein the composition has a melting point from 50 C. to 100 C.

4. The composition according to claim 1 wherein the composition is provided in an at least two-part form and a first part comprises the resin component and a second part comprises the anaerobically curable monomer.

5. The composition according claim 1 wherein the anaerobically curable component is provided in powder form.

6. The composition according to claim 1 wherein the resin component is provided in a flowable particulate form.

7. The composition according to claim 1 wherein the resin component is provided in powder form.

8. The composition according to claim 1 wherein the anaerobically curable monomer is provided in a flowable particulate form.

9. The composition according to claim 1 wherein the anaerobically curable monomer is provided in powder form.

10. The composition according to claim 1 wherein the anaerobically curable component includes the product formed by melting the resin component and the anaerobically curable monomer and blending them and forming a solid blended product.

11. The composition according to claim 10 wherein the composition includes the product formed by reducing the solid blended product into a flowable particulate form.

12. The composition according to claim 6 wherein the particulate form has an average particle size of less than about 500 m.

13. The composition according to claim 1 wherein the anaerobically curable component is present in an amount of from 80% to 99% by weight of the total composition.

14. The composition according to claim 1 wherein the anaerobically curable component is present in an amount of from 93% to 97% by weight of the total composition.

15. The composition according to claim 1 wherein the anaerobically curable resin component is present in an amount of from 10% to 60% by weight based on the total weight of the composition.

16. The composition according to claim 1 wherein the anaerobically curable resin component is present in an amount of from 25% to 50% by weight based on the total weight of the composition.

17. The composition according to claim 1 wherein the anaerobically curable resin component is present in an amount of from 20% to 30% by weight based on the total weight of the composition.

18. The composition according to claim 1 wherein the anaerobically curable resin component is selected from: (meth) acrylated polyurethane resins with a molecular weight of about 2,000 g/mol or higher; novolac resins with a molecular weight of about 2,000 g/mol or higher (meth)acrylated polyester resins and combinations thereof.

19. The composition according to claim 1 wherein the anaerobically curable monomer is present in an amount of from 40% to 90% by weight based on the total weight of the composition.

20. The composition according to claim 1 wherein the anaerobically curable monomer is present in an amount of from 45% to 85% by weight based on the total weight of the composition.

21. The composition according to claim 1 wherein the anaerobically curable monomer is present in an amount from 45% to 70% by weight based on the total weight of the composition.

22. The composition according to claim 1 wherein the anaerobically curable monomer comprises at least one acrylate or methacrylate ester group.

23. The composition according to claim 1 wherein the anaerobically curable component includes at least one of: (meth)acrylated polyurethane resin with a molecular weight of less than about 1000 g/mol, (meth)acrylate monomers, including encapsulated (meth)acrylate monomers; and combinations thereof.

24. The composition according to claim 1 wherein the curing component is present in an amount of from 0.1% to 10% by weight based on the total weight of the composition.

25. The composition according to claim 1 wherein the curing component is present in an amount from 1% to 5% by weight based on the total weight of the composition.

26. The composition according to claim 1 wherein the curing component is present in an amount of about 5% by weight based on the total weight of the composition.

27. The composition according to claim 1 wherein the composition comprises less than 1% solvent by weight based on the total weight of composition.

28. The composition according to claim 27 wherein the solvent is organic solvent or water.

29. A method of providing a threadlocking composition on the threads of a threaded article to be thread locked comprising the steps of: (i) providing in a solid tack-free form a composition according to claim 1; (ii) applying the thread locking composition to the threads of an article so as to fuse it by melting to the threads.

30. The method according to claim 29 comprising the step of: heating the threads of an article to be thread locked to a temperature sufficient to melt the threadlocking composition.

31. The method according to claim 29 wherein the composition is provided in an at least two-part form and those two parts are separately applied.

32. A method of threadlocking two threaded articles together comprising: a. providing a threadlocking composition according to claim 1; b. applying the thread locking composition to the threads of at least one article so as to fuse it by melting to the threads; c. subsequently threading the two articles together so as to initiate anaerobic cure of the threadlocking composition and thus anaerobically cure the composition so as to chemically bond the two articles together.

33. The method according to claim 32 wherein threading the two articles together is carried out after active cooling.

34. The method according to claim 32 wherein threading the two articles together is carried out after passive cooling.

35. An article to which a composition according to claim 1 has been applied.

36. The article according to claim 35 wherein the article is a bolt or nut.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings in which:

(2) FIGS. 1 to 7 are figures illustrating the average break torque (in Nm) achieved for the nut and bolt assemblies as set out below in Examples 1 to 7.

(3) FIGS. 8 to 12 show results of testing from the Examples below and show Average Break Torque (in Nm) for different substrates.

(4) FIGS. 13 and 14 show results of testing from the Examples below and show Average Break Torque (in Nm) on Zinc Phosphate at different temperatures.

(5) FIGS. 15 to 17 show results of testing from the Examples below and show Average Break Torque (in Nm) on Zinc Phosphate or black oxide bolts and mild steel nuts at different temperatures.

DETAILED DESCRIPTION

(6) An example of an composition that may be considered a basis for formulating (100%) solid anaerobic formulations is given below in Table 1:

(7) TABLE-US-00001 TABLE 1 Solid Anaerobic Formulation Component Wt % Resin 25-50 Monomer 45-70 Cure System 4-6 Total 100

(8) The resins and monomers are in general in solid form at room temperature and have a melting point of <100 C. The monomer component above is desirably all solid monomer, but optionally can include up to about 20% (of the overall composition by weight) of liquid monomer. The liquid monomer may be added directly as a liquid to the composition or may be encapsulated. When encapsulated the encapsulated monomer may be present in an amount up to about 20% (of the overall composition by weight).

(9) General examples of types of materials that could be used are given below in Table 2.

(10) TABLE-US-00002 TABLE 2 Examples of types of resins, monomer and initiators that can be used to prepare (100%) solid anaerobic formulation. Resins Monomers Initiators Long chain Short chain (Meth)acrylated Peroxides (Meth) acrylated PU resin with mp 50-80 C. Polyurethane resins (MW > 2,000 g/mol) Novolac Vinyl esters (Meth)acrylate monomers Encapsulated with mp 50-80 C. peroxides Encapsulated (meth)acrylate monomers
Preparation

(11) The raw materials are formulated together at a temperature just above the melting point of the individual components. When the formulation has a homogeneuos appearance, it is allowed to cool to room temperature. At this point, it is a solid. This solid is then ground down to a fine powder (particle size 20-500 m). This can be achieved using a cryogenic ballmill. The resulting powder is free flowing and does not contain any large agglomerates.

(12) Application

(13) The substrate to be coated, in most cases a bolt, is heated up to approx. 80 C. The powder is dispensed on to the hot bolt. Upon touching the hot bolt the powder melts and flows around the threads of the bolts. The extent of the coverage produced can be controlled by various factors such as bolt temperature, and melt viscosity of the powder. As the temperature of the bolts is reduced, the coating solidifies. The process can be expedited by active cooling e.g. placing the substrates in a freezer.

(14) The composition of the invention can thus be provided as a fine powder. It can be applied at a temperature of less than 100 C. It can have a variable profile because the amount of particulate matter that is applied can be varied to suit the application in question. It is an anaerobically curable system so curing in the presence of air is not possible meaning a composition of the invention shows great stability until it is placed in an environment where oxygen (air) is excluded. It shows superior vibration resistance. It also shows improve thermal performance. It also has improved chemical resistance. It can also be utilised with current application systems for example without modifying current dispensing equipment.

EXAMPLES

(15) The formulation of Examples 1 to 7 below were prepared as described above under Preparation and were applied to a bolt as under the heading Application.

(16) Testing was carried out (for Examples 1 to 7) by application to M101.5 bolts. Three different substrates were tested as follows:

(17) 1) Black oxide coated mild steel bolts with mild steel nuts (BO/MS)

(18) 2) Zinc phosphate coated mild steel nut and bolt (ZnP)

(19) 3) Stainless steel nut and bolt (SS)

(20) For each test five of those bolts were used and an average value taken. Nuts of the appropriate type as described above were then applied to the bolts to a torque of >1 N.Math.m to initiate anaerobic cure. After at least 60 minutes the average break torque required to move the nut relative to the bolt was measured in accordance with ISO 10964. The break torque was again measured 24 and 72 hours after the nut and bolt assembly was prepared. The results of the testing of Examples 1 to 7 is set out in FIGS. 1 to 7.

(21) All percentages are percentages by weight based on the total weight of the composition.

Example 1

(22) TABLE-US-00003 Material wt % Methacrylated PU resin 25.0 2-Methacryloxyethylphenylurethane 36.0 Bisphenol A Dimethacrylate 36.0 Cumene Hydroperoxide (CHP) 1.0 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 100

(23) The results of testing with a composition of the invention according to Example 1 are set out in FIG. 1.

Example 2

(24) TABLE-US-00004 Material wt % Novolac Vinyl ester resin 10.0 2-Methacryloxyethylphenylurethane 43.0 Bisphenol A Dimethacrylate 42.0 (CHP) 1.0 PEG 200 dimethacrylate 2.8 Saccharin 0.4 Acetyl Phenyl Hydrazine 0.4 Maleic Acid 0.4 100

(25) The results of testing with a composition of the invention according to Example 2 are set out in FIG. 2.

Example 3

(26) TABLE-US-00005 Material wt % Novolac Vinyl ester resin 25.0 2-Methacryloxyethylphenylurethane 35.0 Bisphenol A Dimethacrylate 34.0 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 BPO Microcaps caps dusted in after 4.0 micronisation 100

(27) The results of testing with a composition of the invention according to Example 3 are set out in FIG. 3.

Example 4

(28) TABLE-US-00006 Material wt % Novolac Vinyl ester resin 25.0 2-Methacryloxyethylphenylurethane 34.5 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 Ethoxylated Bisphenol A Dimethacrylate 34.5 microcaps (E2BDMA caps) dusted in after micronisation BPO Microcaps caps dusted in after 4.0 micronisation 100

(29) The results of testing with a composition of the invention according to Example 4 are set out in FIG. 4.

Example 5

(30) TABLE-US-00007 Material wt % Di-methacrylated PU resin 25.0 RRT600 34.5 2-Methacryloxyethylphenylurethane 34.5 BPO Microcaps 4.0 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 100

(31) The results of testing with a composition of the invention according to Example 5 are set out in FIG. 5.

Example 6

(32) TABLE-US-00008 Material wt % RRT600 25.0 Bisphenol A Dimethacrylate 34.5 2-Methacryloxyethylphenylurethane 34.5 BPO Microcaps 4.0 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 100

(33) The results of testing with a composition of the invention according to Example 6 are set out in FIG. 6.

Example 7

(34) TABLE-US-00009 Material wt % Di-methacrylated PU resin 15.0 Novolac Vinyl Ester Resin 10.0 2-Methacryloxyethylphenylurethane 34.5 Bisphenol A Dimethacrylate 34.5 BPO Microcaps 4.0 PEG 200 dimethacrylate 1.4 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 100

(35) The results of testing with a composition of the invention according to Example 7 are set out in FIG. 7.

(36) The anaerobically curable compositions detailed above in Examples 1 to 7 provided excellent adhesive performance on a range of substrates namely black oxide coated mild steel, zinc phosphate coated mild steel and stainless steel. Full cure strength was achieved within 72 hours of the nut and bolt assembly being prepared. This was confirmed by measuring the breakaway torque values in accordance with ISO 10964, the results of which are given in FIGS. 1 to 7. As this is the first known example of an anaerobically curable composition that is in flowable particulate form, direct comparison cannot be given but the performance of this threadlocker composition is at least comparable to standard liquid anaerobic or other pre-applied threadlocker compositions.

Example 8

Resins and Raw Materials

(37) Examples of starting materials used in the resin synthesis:

(38) Polyols:

(39) (Semi)-crystalline polyester polyols such as those available from Evonik under the Dynacoll trade name e.g. Dynacoll 7380, 7381, 7362

(40) Isocyanates:

(41) Toluene diisocyanate

(42) Methylene diphenyl isocyanate

(43) Hydrogenated Xylylene diisocyanate

(44) Capping agents:

(45) Hydroxyethyl methacrylate

(46) Glycerol dimethacrylate

(47) Example of Resin Synthesis:

(48) Charged Dynacoll 7380 (90.89 g), BHT (butylated hydroxytoluene) (0.03 g), MEHQ (4-methoxyphenol) (0.03 g) and phosphoric acid (0.007 g) to the reaction vessel and mixed while heating to 120 C. Allowed temperature to decrease and mixed for 20 minutes at 100 C. Added DBTDL (dibutyltin dilaurate) (0.037 g) with mixing and then slowly added the TDI (toluene diisocyanate) (6.28 g) into the vessel, maintaining the temperature at 100 C. throughout the reaction. Continued mixing for 2-3 hours or until % wt Isocyanate (NCO) reached equilibrium. Titrated for remaining NCO. Added 90% of the required HEMA (hydroxyethyl methacrylate) (2.5 g) based on titre. Added DBTDL (0.037 g). Allowed to react for 3 hours and monitored the NCO consumption via titration. Where the % NCO remaining is >0.2% charged the calculated 2nd addition of HEMA. Stopped the reaction when NCO content is <0.2%.

Example 9

(49) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(50) TABLE-US-00010 Material wt % Di-functional methacrylated PU resin 25.0 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 37.0 RRT600 37.0 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 PEG 200 dimethacrylate 1.4 BPO microcaps 4.0 Total 100 Melt temperature 70 C. Dry-to-touch time at RT <5 min

(51) The results of cure speed on different substrates as carried out according to ISO 10964 are shown in FIG. 8.

Example 10

(52) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(53) TABLE-US-00011 Material % Di-functional methacrylated PU resin 25.0 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 37.0 Ethoxylated Bisphenol A Dimethacrylate 32.0 microcaps Ethoxylated Bisphenol A Dimethacrylate 5.0 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 PEG 200 dimethacrylate 1.4 BPO microcaps 4.0 100 Melt temperature 70 C. Dry-to-touch time at RT <3 min

(54) The results of cure speed on different substrates as carried out according to ISO 10964 are shown in FIG. 9.

Example 11

(55) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(56) TABLE-US-00012 Material wt % Di-functional methacrylated PU resin 25.0 from semi crystalline polyol Di-functional methacrylated PU resin 20.0 from amorphous polyol 2-Methacryloxyethylphenylurethane 24.0 RRT600 25.0 Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 PEG 200 dimethacrylate 1.4 BPO microcaps 4.0 100 Melt temperature 70 C. Dry-to-touch time at RT <5 min

(57) The results of cure speed on different substrates as carried out according to ISO 10964 are shown in FIG. 10.

Example 12

(58) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(59) TABLE-US-00013 Material wt % Di-functional methacrylated PU resin 25.0 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 37.0 Ethoxylated Bisphenol A Dimethacrylate 37.0 microcaps Saccharin 0.2 Acetyl Phenyl Hydrazine 0.2 Maleic Acid 0.2 PEG 200 dimethacrylate 1.4 BPO microcaps 4.0 100 Melt temperature 70 C. Dry-to-touch time at RT <5 min

(60) The results of cure speed on different substrates as carried out according to ISO 10964 are shown in FIG. 11.

Example 13

(61) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(62) TABLE-US-00014 Material wt % Tetra-functional Methacrylated PU resin 35.0 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 35.0 4RRT600 25.4 Maleic acid 0.2 Acetyl phenyhydrazine 0.2 Saccharin 0.2 BPO Microcaps 4.0 100.0 Melt temperature 80 C. Dry-to-touch time at RT <5 min

(63) The results of break torque on different substrates as carried out according to ISO 10964 are shown in FIG. 12.

Example 14

(64) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(65) TABLE-US-00015 Material wt % Tetra-functional Methacrylated PU resin 32.5 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 32.5 4RRT600 25.4 Bis-(3-ethyl-5-methyl-4-maleinidophenyl)methane 5.0 Maleic acid 0.2 Acetyl phenylhydrazine 0.2 Saccharin 0.2 BPO Microcaps 4.0 100.0 Melt temperature 80 C. Dry-to-touch time at RT <5 min 100.0 Melt temperature 80 C. Dry-to-touch time at RT <5 min

(66) The results of hot strengths on Zinc Phosphate as carried out according to ISO 10964 are shown in FIG. 13.

Example 15

(67) The resin prepared in Example 8 above was formulated with other components to form a composition of the invention as follows:

(68) TABLE-US-00016 Material % Tetra-functional Methacrylated PU resin 31.65 from semi line polyol 2-Methacryloxyethylphenylurethane 31.65 RRT600 22.94 Tricyclodecane dimethanol dimethacrylate 9.04 Maleic acid 0.23 Acetyl phenyhydrazine 0.23 Saccharin 0.23 BPO Microcaps 4.00 100.0 Melt temperature 80 C. Dry-to-touch time at RT <5 min

(69) The results of hot strengths on Zinc Phosphate as carried out according to ISO 10964 are shown in FIG. 14.

Example 16

(70) A composition of the invention for use as a pre-applied flange sealant formulation was prepared having the following composition:

(71) TABLE-US-00017 Material wt % Tetra-functional Methacrylated PU resin 30.28 from semi crystalline polyol 2-Methacryloxyethylphenylurethane 30.28 RRT600 21.98 Tricyclodecane dimethanol dimethacrylate 8.65 Bis-(3-ethyl-5-methyl-maleinidophenyl) methane 4.15 Maleic acid 0.22 Saccharin 0.22 Acetyl phenyl hydrazine 0.22 BPO microcaps 4 100

(72) A formulation with typical peroxides such as cumene hydroperoxide and para menthane hydroperoxide may also be used instead of the benzoyl peroxide microcaps in the above formulation.

(73) This pre-applied flange sealant formulation was applied onto an aluminum surface of a mating flange at 80 C. using a hot-melt dispensing system attached to robot and allowed to cool. The material is dry to touch in less than 5 minutes.

(74) The mating parts were the assembled and torqued down to 10 Nm. An instant seal test was performed 2 minutes after assembly. There was no leakage when tested against air at 1 bar (0.1 MPa) pressure. The product was then allowed to cure for 24 hours at room temperature. A further pressure test against air at 6 bar (0.6 MPa) for 1 hour was performed. Again no leakage was observed.

(75) Adhesion (tensile strength) was measured according to ISO 4587 by applying the pre-applied flange sealant formulation onto the surface of one lap shear and assembling the joint with a second lap shear by applying 4 bar (0.4 MPa) pressure. After curing for 72 hours at room temperature, the results are set out below.

(76) TABLE-US-00018 Aluminum Mild Steel 3.10 MPa 3.22 MPa

Example 17

(77) A formulation was prepared as follows:

(78) TABLE-US-00019 Example 17 wt % Methacrylated PU resin 15.00 2-MAPU (2-Methacryloxyethylphenylurethane) 7.50 RRT600 7.50 Maleic acid 0.06 Saccharin 0.06 APH 0.06 Red dye 0.02 BPO Microcaps 1.20

(79) This formulation was heated to 80 C. and a sample of melted material was placed between two glass plates and clamped. Gap wire (250 m) was placed in between the glass plates to provide spacing to create a smooth film. The glass plates with the melted anaerobic formulation was placed in the oven again for 20 mins to allow the formulation to spread out, providing a level, thin film. The plates were removed from the oven and allowed to cool. At room temperature the solid tape/film was cut into strips and applied to the threaded parts as required.

(80) The tape was then applied to the (zinc phosphate) ZnP bolts and the nuts were torqued on afterwards. It is to be noted that no melting is required to apply the compositions of the invention, in this case in tape form. The tape/film was applied to cold ZnP bolts. No heat was required to apply the (solid) adhesive tape. It is sufficiently flexible to allow application. The composition was then allowed to cure at room temperature for 16 to 17 hours.

(81) The first samples prepared had the formulation above, but had no peroxide microcaps present. The break torques were tested according to ISO 10964 and the results are as follows:

(82) TABLE-US-00020 Example 17 Break (no BPO) N .Math. m 1 0.8 2 1.6 3 0.4 4 0.4 Avg. 0.8

(83) A second set of samples were prepared this time including the peroxide microcaps. This second formulation contains peroxide microcaps and shows a significant increase in torque strength as follows:

(84) TABLE-US-00021 Example 17 Break (with BPO) N .Math. m 1 4.0 2 5.9 3 6.4 4 4.7 5 4.7 Avg. 5.4

(85) A comparison of the average break torque for the two formulations is shown in FIG. 15.

Example 18

(86) A tape was prepared as described above in Example 16 and using the following Example 18 formulation:

(87) TABLE-US-00022 Material wt % Di-functional methacrylated PU resin 14.0 from amorphous polyol Novolac Vinyl Ester Resin 7.00 Di-functional methacrylated PU resin 3.50 from crystalline polyol Maleic acid 0.06 Saccharin 0.06 APH (acetyl phenyl hydrazine) 0.06 Red Dye 0.02 BPO Microcaps 1.20

(88) The tape was applied to black oxide bolts and mild steel nuts and cured for 1 hour, overnight (24 hours), and 1 week (168 hours) at room temperature (RT). The break torques were tested according to ISO 10964 and the results are as follows:

(89) TABLE-US-00023 Break N .Math. m 1 h @ RT Black Oxide bolts and mild steel nuts 1 1.2 2 1.6 3 2.7 4 0.8 5 1.9 Avg. 1.6 24 h @ RT Black Oxide bolts and mild steel nuts 1 4.4 2 3.7 3 5.9 4 5.8 5 4.4 Avg. 4.8 168 h @ RT Black Oxide bolts and mild steel nuts 1 9.8 2 10.4 3 12.0 4 10.1 5 9.5 Avg. 10.4

(90) A comparison of the average break torque for these tests is shown in FIG. 16.

Example 19

(91) A tape was prepared as described above in Example 16 and using the following Example 19 formulation:

(92) TABLE-US-00024 Material Formulation g Novolac Vinyl Ester Resin 9.52 TCDDMA (tricyclodecane dimethanol dimethacrylate) 0.10 Acetyl phenyl hydrazine 0.05 Maleic acid 0.05 Saccharin 0.08 BPO Micro-caps 0.20

(93) The tape was applied to ZnP nuts and bolts and cured overnight (24 hours), at room temperature (RT). The break torques were tested according to ISO 10964 at various temperatures and the results are as follows:

(94) TABLE-US-00025 24 h @ RT on ZnP nuts and bolts Break N .Math. m 1 7.5 2 9.9 3 8.7 Avg. 8.7
Hot Strengths

(95) Samples cured for 24 h and tested @100 C.

(96) TABLE-US-00026 Break N .Math. m 1 7 2 8.3 3 8.7 Avg. 8.0

(97) Samples cured for 24 h and tested @120 C.

(98) TABLE-US-00027 Break N .Math. m 1 7.3 2 7.6 3 6.9 Avg. 7.3

(99) Samples cured for 24 h and tested @150 C.

(100) TABLE-US-00028 Break N .Math. m 1 6.3 2 7.2 3 6.8 Avg. 6.8

(101) A comparison of the average break torque for these tests is shown in FIG. 17.

(102) In the Examples: Methacrylated PU resin is methacrylate terminated urethane polyester resin (M.W.=5,000 g/mol) (see discussion above) CHP is cumene hydroperoxide Novolac vinyl ester resin is: Phenol formaldehyde novolac vinyl ester resin (see discussion above) having a molecular weight of about 6,000 g/mol. BPO caps are benzoyl peroxide microcapsules E2BDMA microcaps are ethoxylated bisphenol A dimethacrylate in a urea/formaldehyde shell.

(103) 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.

(104) 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.