3M

Scotch-WeldTM

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Technical Data

 

 

 

March, 2015

 

 

 

 

 

 

 

Product Description

3MTM Scotch-WeldTM Epoxy Potting Compound/Adhesive DP270 (or 3M™ Scotch-

 

Weld™ Epoxy Potting Compound/Adhesive 270 B/A) is a two-part, low viscosity

 

epoxy resin system designed primarily for potting, sealing, and encapsulation of

 

many electronic components and is available in clear or black. Scotch-Weld epoxy

 

potting compound/adhesive DP270 is noncorrosive to copper and offers good

 

thermal shock resistance and excellent retention of electrical insulation properties

 

under high humidity conditions.

 

 

 

3M™ Scotch-Weld™ epoxy potting compound/adhesive DP270 has a work life

 

of approximately 70 minutes, a tack-free time of about 3 hours and is fully cured

 

after 48 hours at 73°F (23°C). This product produces no exotherm in 5-10 gram

 

masses and a very slight exotherm in larger masses.

 

3M™ Scotch-Weld™ epoxy potting compound/adhesive DP270 is ideal for the

 

potting and encapsulation of many heat sensitive or delicate components such as

 

glass diodes and sensors as well as for transformers, coils, chokes, relays, etc. It is

 

available in the convenient 3M™ EPX™ Applicator System for multi-station usage

 

and in bulk containers for larger volume applications.

 

Available in bulk containers as Scotch-Weld epoxy potting compound/adhesive

 

270 B/A.

 

 

 

 

 

 

 

Features

•

Good Thermal Shock Resistance

•

Excellent Electrical Properties

 

•

Meets UL 94 HB (File No. E61941)

•

Noncorrosive to Copper

 

•

Long Worklife

•

Negligible Exotherm

Typical Uncured

Properties

Note: The following technical information and data should be considered representative or typical only and should not be used for specification purposes.

Color:

Clear or Black

 

 

 

 

Base Resin:

Epoxy/amine

 

 

 

Mix Ratio:

1:1 by volume (1:0.85 B:A by weight)

 

 

 

Net Weight:

Base 9.6 - 9.7

 

Lbs./Gal.

Accelerator 8.0 - 8.2

 

 

Worklife:

60-70 minutes @ 23°C (73°F)

 

 

 

Viscosity:

Base

7000 - 16,000 cps

@ 23°C (73°F)

Accelerator

6000 - 12,000 cps

 

 

 

3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Typical Cured

Properties

Note: The following technical information and data should be considered representative or typical only and should not be used for specification purposes.

Physical:

Color

Clear or Black

Refractive Index @ 25°C (77°C)

Clear 1.656

Cure Shrinkage

.08%

Shore D Hardness

83

(ASTM D-2240)

 

Tack-free Time

Approx. 3 hrs. @ 23°C (73°F)

UL Rating

94 HB (File No. E61941)

Cure Time

48 hrs. @ 23°C (73°F)

Thermal:

Weight Loss by TGA (in air)

1% @ 122°C (252°F)

 

5% @ 175°C (347°F)

 

10% @ 210°C (410°F)

Thermal Coefficient of Expansion by TMA

 

Below Tg

80 x 10-6 units/unit/°C

 

5-30°C range (10-86°F range)

Above Tg

180 x 10-6 units/unit/°C

 

60-125°C range (140-257°F)

Glass Transition Temperature by DSC

 

Onset

43°C (109°F)

Mid-Point

49°C (120°F)

Thermal Conductivity

 

(@ 110°F on .250" samples)

 

BTU - ft./ft.2 - hr. - °F

.103

Cal./sec. - cm - °C

.426 x 103

Watt/m - °C

.177

Thermal Shock Resistance

 

Potted Washer Olyphant Test

Pass 5 Cycles without cracking

3M Test Method C-3174

 

+100°C (air) to -50°C (liquid)

 

Electrical:

Dielectric Constant

3.5 @ 1 KHz @ 23°C (73°F)

(ASTM D-150)

 

Dissipation Factor

.018 @ 1 KHz @ 23°C (73°F)

(ASTM D-150)

 

Dielectric Strength

850 volts/mil

(ASTM D-149)

 

Volume Resistivity

4.1 x 1014 ohm-cm

(ASTM D-257)

 

Insulation Resistance

 

(.8 mm/.8 mm comb pattern on FR-4)

 

60°C/96% R.H./100 volts d.c.)

 

Initial

3 x 1013 ohms

1000 hrs.

2 x 1011 ohms

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3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Additional Electrical Note: The following technical information and data should be considered representative or

Properties

typical only and should not be used for specification purposes.

 

Dissipation Factor

Dielectric Constant

 

Versus Frequency

Versus Frequency

Dissipation Factor

.030

.025

.020

.015

.010

100Hz

1 KHz

10 KHz 100 KHz 1 MHz

FREQUENCY

 

3.8

 

 

 

 

 

3.6

 

 

 

 

Constant

3.4

 

 

 

 

Dielectric

 

 

 

 

 

 

 

 

 

 

3.2

 

 

 

 

 

3.0

 

 

 

 

 

100Hz

1 KHz

10 KHz

100 KHz

1 MHz

 

 

 

FREQUENCY

 

Insulation Resistance

.8 mm/.8 mm Comb Pattern 60°C (140°F)/95% RH/100 V d.c.

 

15

 

 

 

 

 

 

(1 x 10 ohms)*

14

 

 

 

 

 

 

 

 

 

 

 

 

 

of Resistance

13

 

 

 

 

 

 

 

 

 

 

 

 

 

Log

12

 

 

 

 

 

 

 

 

 

 

 

 

 

 

11

 

 

 

 

 

 

 

0

200

400

600

800

1000

1200

 

 

 

 

HOURS

 

 

 

*The numbers on the vertical axis represent the exponential power on the 1 x 10 ohm notation.

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3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Typical Cured

Properties (continued)

Note: The following technical information and data should be considered representative or typical only and should not be used for specification purposes.

Corrosion:

Per ASTM D-3482

 

(35°C/95°F/96% R.H./45V d.c./15 days)

Pass - No copper corrosion

Per 3M Test Method C-708

 

(45°C/113°F/96% R.H./250V d.c./5 days)

Pass - No copper corrosion

(65°C/149°F/96% R.H./250V d.c./4 days)

Pass - No copper corrosion

Per Mil S-46163

 

(10 days/50% R.H./23°C/73°F)

Pass - No aluminum, brass or steel

 

discoloration or corrosion

Solvent Resistance:

(Visual check after immersion in specified solvent at 23°C (73°F)

 

1 Hour

1 Month

Acetone

B

C

Isopropyl Alcohol

A

B

Freon TF

A

A

Freon TMC

B

C

1,1,1-Trichloroethane

A

C

RMA Flux

A

B

Key: A - Unaffected

 

 

B - Slight Attack

 

 

C - Moderate/Severe Attack

Typical Adhesive

Performance

Characteristics

Note: The following technical information and data should be considered representative or typical only and should not be used for specification purposes.

Although 3M™ Scotch-Weld™ Epoxy Potting Compound/Adhesive DP270 and 270 B/A can be used for many potting and encapsulation applications, they can also be used as adhesives. The following shows typical shear and peel values determined on several common substrates:

Overlap Shear Adhesion (ASTM D-1002-72)

 

Curing Conditions

 

7 days/73°F (23°C)

 

 

 

Alum./Alum. (etched)

@-67°F (-55°C)

1200-1250 psi

 

@73°F (23°C)

2450-2500 psi

 

@180°F (82°C)

300-350 psi

 

 

 

FR-4/FR-4 (MEK Wiped)

@73°F (23°C)

1750-1800 psi

 

 

 

Copper/Copper (MEK Wiped)

@73°F (23°C)

1700-1750 psi

 

 

 

90° T-Peel Adhesion (ASTM D-1876-61T)

Alum./Alum. (etched)

@73°F (23°C)

< 2 piw

 

 

 

Compression Strength (ASTM D-695-68T)

Scotch-Weld epoxy potting compound/adhesive

@73°F (23°C)

8100 psi

DP270 Clear and Black

 

 

 

 

 

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3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

3M™ EPX™

200 ml Applicator – Maximum Pressure 58 psi

 

Pneumatic Applicator

 

 

 

Delivery Rates

 

 

 

 

 

6mm Nozzle

10mm Nozzle

 

Adhesive*

gms/minute

gms/minute

 

 

 

 

 

3M™ Scotch-Weld™ Epoxy Potting

38.2

148.8

 

Compound/Adhesive DP270 Black

 

 

 

 

 

 

50 ml Applicator – Maximum Pressure 50 psi

 

1/4 in. Nozzle

Adhesive*

gms/minute

 

 

3M™ Scotch-Weld™ Epoxy Potting

75.6

Compound/Adhesive DP270 Clear

 

Scotch-Weld epoxy potting

68.6

compound/adhesive DP270 Black

 

 

 

*Tests were run at a temperature of 70°F ± 2°F (21°C ± 1°C) and at maximum applicator pressure.

Handling/Curing

Information

Directions for Use

1.For high strength structural bonds, paint, oxide films, oils, dust, mold release agents and all other surface contaminants must be completely removed. However, the amount of surface preparation directly depends on the required bond strength and the environmental aging resistance desired by user. For specific surface preparations on common substrates, see the section on surface preparation.

2.These products consist of two parts.

Mixing

For Duo-Pak Cartridges

3M™ Scotch-Weld™ epoxy potting compound/adhesive DP270 Clear and Black are supplied in a dual syringe plastic duo-pak cartridge as part of the 3M™ EPX™ Applicator systems. To use, simply insert the duo-pak cartridge into the EPX applicator and start the plunger into the cylinders using light pressure on the trigger. Next, remove the duo-pak cartridge cap and expel a small amount of adhesive to be sure both sides of the duo-pak cartridge are flowing evenly and freely. If mixing of Part A and Part B is desired, attach the EPX applicator mixing nozzle to the duo-pak cartridge and begin dispensing the adhesive. For hand mixing, expel the desired amount of material and mix thoroughly to obtain a uniform color.

For Bulk Containers

Mix thoroughly by weight or volume in the proportions specified in the typical uncured properties section to obtain a uniform color.

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3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Handling/Curing

3.

For maximum bond strength apply product evenly to both surfaces to be joined.

Information (continued)

4.

Application to the substrates should be made within 70 minutes. Larger quantities

 

 

 

and/or higher temperatures will reduce this working time.

 

5.

Join the adhesive coated surfaces and allow to cure at 60°F (16°C) or above until

 

 

firm. Heat up to 200°F (93°C) will speed curing.

 

6.

The following times and temperatures will result in a full cure of these products.

 

 

23°C (73°F)

48 Hours

 

 

50°C (122°F)

4 Hours

 

 

80°C (176°F)

60 Minutes

 

 

100°C (212°F)

30 Minutes

 

7.

Keep parts from moving during cure. Contact pressure necessary. Maximum shear

 

 

strength is obtained with a 3-5 mil bond line.

 

8.

Excess uncured adhesive can be cleaned up with ketone type solvents*.

*Note: When using solvents, extinguish all ignition sources, including pilot lights, and follow the manufacturer’s precautions and directions for use.

Adhesion Coverage: A 0.005 in. thick bondline will yield a coverage of 320 sq. ft./gallon

Application and

These products may be applied by spatula, trowel or flow equipment.

Equipment Suggestions

Two part mixing/proportioning/dispensing equipment is available for intermittent or

 

 

production line use. These systems are ideal because of their variable shot size and

 

flow rate characteristics and are adaptable to most applications.

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3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Surface Preparation

For high strength structural bonds, paint, oxide films, oils, dust, mold release agents

 

and all other surface contaminants must be completely removed. However, the

 

amount of surface preparation directly depends on the required bond strength and the

 

environmental aging resistance desired by user.

 

The following cleaning methods are suggested for common surfaces:

Steel

1.Wipe free of dust with oil-free solvent such as acetone, isopropyl or alcohol solvents.*

2.Sandblast or abrade using clean fine grit abrasives.

3.Wipe again with solvent to remove loose particles.

4.If a primer is used, it should be applied within 4 hours after surface preparation.

Aluminum

1.Alkaline Degrease: Oakite 164 solution (9-11 oz./gallon water) at 190°F ± 10°F (88°C ± 5°C) for 10-20 minutes. Rinse immediately in large quantities of cold running water.

2.Acid Etch: Place panels in the following solution for 10 minutes at 150°F ± 5°F (66°C ± 2°C).

Sodium Dichromate

4.1 - 4.9 oz./gallon

Sulfuric Acid, 66°Be

38.5 - 41.5 oz./gallon

2024-T3 aluminum (dissolved)

0.2 oz./gallon minimum

Tap water as needed to balance

 

3.Rinse: Rinse panels in clear running tap water.

4.Dry: Air dry 15 minutes; force dry 10 minutes at 150°F ± 10°F (66°C ± 5°C).

5.If primer is to be used, it should be applied within 4 hours after surface preparation.

Plastics/Rubber

1.Wipe with isopropyl alcohol.*

2.Abrade using fine grit abrasives.

3.Wipe with isopropyl alcohol.*

Glass

1.Solvent wipe surface using acetone or MEK.*

2.Apply a thin coating (0.0001 in. or less) of 3M™ Scotch-Weld™ Metal Primer EC3901 to the glass surfaces to be bonded and allow the primer to dry 60 minutes before bonding.

*Note: When using solvents, extinguish all ignition sources, including pilot lights, and follow the manufacturer’s precautions and directions for use.

- 7 -

3M™ Scotch-Weld™

Epoxy Potting Compound/Adhesive

DP270 Clear and Black

Storage

Store product at 60-80°F (16-27°C) for maximum storage life.

 

 

Shelf Life

These products when stored in original, unopened container have a shelf life of two

 

years for bulk containers and 15 months in duo-pak containers.

Precautionary

Information

Refer to Product Label and Material Safety Data Sheet for health and safety information before using this product. For additional health and safety information, call 1-800-364-3577 or (651) 737-6501.

Technical Information

The technical information, recommendations and other statements contained in this document are based upon tests or experience that 3M believes are reliable, but the accuracy or completeness of such information is not guaranteed.

Product Use

Many factors beyond 3M’s control and uniquely within user’s knowledge and control can affect the use and performance of a 3M product in a particular application. Given the variety of factors that can affect the use and performance of a 3M product, user is solely responsible for evaluating the 3M product and determining whether it is fit for a particular purpose and suitable for user’s method of application.

Warranty,

Limited Remedy,

and Disclaimer

Unless an additional warranty is specifically stated on the applicable 3M product packaging or product literature, 3M warrants that each 3M product meets the applicable 3M product specification at the time 3M ships the product. 3M MAKES NO OTHER WARRANTIES OR CONDITIONS, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OR CONDITION OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR ANY IMPLIED WARRANTY OR CONDITION ARISING OUT OF A COURSE OF DEALING, CUSTOM OR USAGE OF TRADE.

If the 3M product does not conform to this warranty, then the sole and exclusive remedy is, at 3M’s option, replacement of the 3M product or refund of the purchase price.

Limitation of Liability

Except where prohibited by law, 3M will not be liable for any loss or damage arising from the 3M product, whether direct, indirect, special, incidental or consequential, regardless of the legal theory asserted, including warranty, contract, negligence or strict liability.

ISO 9001: 2000

This Industrial Adhesives and Tapes Division product was manufactured under a 3M quality system registered to ISO 9001: 2000 standards.

3M

Industrial Adhesives and Tapes Division

3M Center, Building 225-3S-06 St. Paul, MN 55144-1000

800-362-3550 • 877-369-2923 (Fax) www.3M.com/structuraladhesives

3M, Scotch-Weld and EPX are trademarks of 3M Company.

©3M 2015

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