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Description for Henkel 661
A two-part, rapid, room temperature cure, toughened acrylic adhesive that combines ease of use with a high level of performance. The cured adhesive provides a combination of high shear and impact strength with excellent durability.Brand Bondmaster Chemical Resistance Acetone, Diesel Fuel, Gasoline, Isopropyl Alcohol, Salt Spray Application Type Bond 1 Part or 2 Part 2-Part Material Form Liquid Substrate Acrylic, Phenolic, Glass, Metals, Ferrite, Neodymium iron boron, Zinc Dichromate, ABS, Rigid Plastics, Polycarbonate, PVC, Galvanized Steel, Steel, Stainless Steel, Aluminum, Galvanized Steel, Alnico, Zinc Plated, Zinc plated Steel, Epoxy-Coated Metal, Zinc plated Steel, Painted Metal, Samarian cobalt Industry DC motors, Electrical, Magnet, Tags, Signs, Automotive, Marine, Nameplates, Generators Manufacturer Henkel Chemistry Acrylic, Toughened Cure Method Part A/Part B Cure Temperature (°C) 20 to 25, 20 to 25 Cure Time (min) Rapid, 60 Viscosity (cPs) 8,500 Color Dark Green High Temperature Resistance (°C) 155 Low Temperature Resistance (°C) -65 Durability Excellent Durability -
Technical Data for Henkel 661
Overview
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Chemical Resistance
- Chemical Resistance - Acetone, Diesel Fuel, Gasoline, Isopropyl Alcohol, Salt Spray
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Application Type
- Adhesive - Bond
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1 Part or 2 Part
- 2-Part
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Material Form
- Liquid
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Substrate
- Ceramic - Ferrite
- Glass
- Metal - Alnico, Epoxy-Coated Metal, Metals, Painted Metal, Samarian cobalt
- Iron - Neodymium iron boron
- Zinc - Zinc Dichromate, Zinc Plated, Zinc plated Steel
- Steel - Zinc plated Steel
- Aluminum
- Galvanized - Galvanized Steel
- Plastic - Rigid Plastics
- Acrylic (PMMA) - Acrylic
- Phenolic
- ABS
- Polycarbonate
- Polyvinyl chloride (PVC) - PVC
- Galvanized Steel
- Stainless Steel
- Other - Rare earth
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Industry
- Sign - Signs
- Marine
- Automotive
- Electronics - Electrical, Generators
- Speakers
- Industrial - Basket, Housings, Nameplates, Pole piece, Signs, Tags
- Motors - DC motors
- Magnet
- Printing and Graphics - Nameplates, Tags
- Appliances
- Construction - Frames
- Furniture / Wood-Working - Furniture
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Chemistry
- Toughened
- Acrylic
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Cure Method
- 2-Part Cure - Part A/Part B
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Color
- Green - Dark Green
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Brand
- Bondmaster
Specifications
Cure Specs
Cure Temperature (°C) 20 to 25, 20 to 25 Cure Time (min) Rapid, 60 Viscosity (cPs) 8,500 Test Method Fixture or Handling Strength Time (min) 0.75 to 1.50 Test Method Work / Pot Time (min) 0.50 Test Method Mix Ratio 1:1 (by volume), 1:1 (by weight) Bond Strength
Structural/Load-Bearing Structural Peel Strength (piw) High, 10 to 20 (pli) Test Method Shear Strength (psi) High, 2,500 to 3,000, 2,000 to 2,800, 1,500 to 2,500, 2,500 to 3,000, 2,000 to 2,800, 2,000, 2,000, 2,000, 2,000, 250, 300 to 400, 300 to 400, 50 to 100, 80 to 120, 200 to 300 Test Method Impact Strength (psi) High, 8 to 10 (ft-lb / in2) Test Method Material Resistance
High Temperature Resistance (°C) 155 Low Temperature Resistance (°C) -65 Impact Resistance Impact resistance Moisture/Humidity Resistance Moisture/humidity resistance Hardness
Durability Excellent Durability Shore D Hardness 60 to 65, 55 to 60, 40 to 45 Test Method Other Properties
Glass Transition Temp (Tg) (°C) 57 Specific Gravity 0.965 Flash Point (°F) 201.2 % Solids (%) 100 Business Information
Shelf Life Details Shelf life Part A, Package sizes larger than 2000ml six months. , Shelf life Part B, Package sizes larger than 2000ml six months. , Shelf life Mix, BONDMASTER 661 has a shelf life of one year when stored in a refrigerator. Keep away from excessive heat, sparks, flame, and sunlight. Shelf Life Temperature (°F) 36 to 45, 36 to 45 Shelf Life (mon) 12, 12, 12 Not Good For
Don't Use With Delrin, Polyethylene, Polypropylene, Polyurethane, Any type of elastomer, Acetal -
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Best Practices for Henkel 661
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Surface Preparation
Minimal Surface Preparation Required.
The 661 adhesive requires no surface preparation on most metal, ferrite, and glass surfaces. For optimum bond strength on metal parts the surface should be washed with a solvent or cleansing solution, abraded with an abrasive pad, and then rinsed with a solvent or cleansing solution. Glass surfaces should be cleaned with a commercial glass cleaner before bonding. Painted surfaces should be abraded lightly and then wiped clean.
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Application
BONDMASTER's Equipment Group has a complete line of industrial dispensing equipment to dispense the 661 in magnet bonding applications. Equipment is available to dispense the adhesive through BONDMASTER's unique External Mix dispensing process. The External Mix Dispensing System is a technology that results in high performance without the use of a static mixer. This allows the use of the adhesive in high-speed production without having to change static mixers frequently. The External Mix technology also provides the user with a higher performance than conventional bead on bead systems.
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Mixing
For optimum performance, 661 should be mixed in a 1:1 (A:B) ratio. However, the adhesive has a very forgiving mix ratio, and complete cure can be achieved even when the adhesive is not mixed exactly in a one to one ratio.
BONDMASTER 661 Part A & Part B should not be mixed in large quantities, as a vigorous chemical reaction will occur generating a significant amount of heat and vapors.
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Curing
Exposure to air will inhibit the cure of all acrylic adhesives. Because of this inhibition, the exposed surface of any mixed adhesive squeezed outside the bondline will remain tacky for a few hours. Only the cure of the exposed surface is inhibited, not the adhesive in the bondline.
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Clean-Up
Unreacted Part A & Part B can be cleaned up using acetone, isopropanol, or MEK.
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Comparable Materials for Henkel 661
Spec Engine® Results
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Fixture or Handling Strength Time Test Methods
Fixture or Handling Strength Time | Fixture-Handling Strength Time Temperature |
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0.75 to 1.50 min | 25°C |
Viscosity Test Methods
Viscosity | Test Method | Temperature |
---|---|---|
8,500 cPs | Viscosity, Brookfield, 25oC 77°F @ 20 rpm | 25°C |
Work / Pot Time Test Methods
Work / Pot Time | Temperature |
---|---|
0.50 min | 25°C |
Shear Strength Test Methods
Shear Strength | Type | Substrate | Test Temperature | Test Method |
---|---|---|---|---|
High | ||||
2,500 to 3,000 psi | Lap shear strength | Steel/Steel | 25°C | ASTM D-1002 |
2,000 to 2,800 psi | Lap shear strength | Aluminum/Aluminum | 25°C | ASTM D-1002 |
1,500 to 2,500 psi | Lap shear strength | Galvanized steel/Galvanized steel | 25°C | ASTM D-1002 |
2,500 to 3,000 psi | Lap shear strength | Stainless Steel/Stainless Steel | 25°C | ASTM D-1002 |
2,000 to 2,800 psi | Lap shear strength | Zinc plated steel/Zinc plated steel | 25°C | ASTM D1002 |
2,000 psi | Lap shear strength | Ferrite/Steel | 25°C | ASTM D-1002, Substrate Failure |
2,000 psi | Lap shear strength | Ferrite/Zinc Dichromate | 25°C | ASTM D-1002, Substrate Failure |
2,000 psi | Lap shear strength | Ferrite/Galvanized Steel | 25°C | ASTM D-1002, Substrate Failure |
2,000 psi | Lap shear strength | Ferrite/Zinc plated | 25°C | ASTM D-1002, Substrate Failure |
250 psi | Lap shear strength | Glass/Glass | 25°C | ASTM D1002, Substrate Failure |
300 to 400 psi | Lap shear strength | Phenolic/Phenolic | 25°C | ASTM D1002 |
300 to 400 psi | Lap shear strength | PVC/PVC | 25°C | ASTM D1002 |
50 to 100 psi | Lap shear strength | Polycarbonate/Polycarbonate | 25°C | ASTM D1002 |
80 to 120 psi | Lap shear strength | ABS/ABS | 25°C | ASTM D1002 |
200 to 300 psi | Lap shear strength | Acrylic/Acrylic | 25°C | ASTM D1002 |
Peel Strength Test Methods
Peel Strength | Type | Substrate | Test Method |
---|---|---|---|
High | |||
10 to 20 (pli) | T-Peel strength | Steel/Steel | ASTM 1876 |
Impact Strength Test Methods
Impact Strength | Substrate | Test Method |
---|---|---|
High | ||
8 to 10 (ft-lb / in2) | Steel/Steel | ASTM 950 |
Shore D Hardness Test Methods
Shore D Hardness | Hardness Temperature |
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60 to 65 | 25°C |
55 to 60 | 50°C |
40 to 45 | 100°C |