PT2520 Unfilled High Temperature Epoxy Laminating System


PT2520 is an amber, unfilled epoxy laminating resin designed for the construction of tooling and components that will operate in the intermediate high temperature service range. PT2520 will gel at room temperature for subsequent oven post curing off the pattern with both of the Part B hardeners listed here. Part B and Part B1 hardeners have different working times, so that by selecting the proper hardener, various sized tools and parts can be fabricated. PR2520 Part B has a 45 to 50 minute pot life, and the Part B1 has a 4 to 4.5 hour pot life, depending upon shop temperature. The mixed viscosity of PT2520 provides a system that penetrates the reinforcing fabric quite readily and holds the fabric in place, for fast, reliable fabrication. With the capability to post cure the laminate off the pattern, it is possible to use low temperature pattern materials such as wood or plaster for lower fabrication costs, since they will not be put into the oven for post cure. PT2520 has found good acceptance in such applications as vacuum form tools, foam molds, bond fixtures, layup molds, resin transfer molds, and other situations where
repetitive heating and cooling cycles are involved.
There are no restricted or regulated raw materials used in these high temperature products. PT2520 Part A does not contain vinylcyclohexane diepoxide (VCHD), or other hazardous or potentially restricted diluents. The PT2520 Part B hardeners do not contain methylene dianiline (MDA) or other potentially harmful aniline derivatives. They are non-staining, and will not crystallize in normal shipping and storage conditions.

 PT2520 A
PT2520 B
PT2520 B1
ASTM Method 
2650 cps
1700 cps
500 cps
Specific Gravity, gms./cc
Mix Ratio, by Weight

100 : 16
100 : 19
Pot Life, 4 fl oz Mass @ 77°F
45 – 50 min.
4 – 4.5 hr.


When using PT2520 Part B, the system will gel hard in 18 to 24 hours at 77°F. In lower temperature service, non-critical applications, the system can usually achieve its full cure in service. However, for maximum stability, an oven post cure is recommended, and is mandatory in applications where continuous service temperature is over 250°F. When using the Part B1 hardener, under normal conditions the system will gel to a hard demoldable state in 24 to 36 hours. In colder shop environments, or unusual conditions, the user should check closely to insure that the resin has fully gelled before the tool is post cured.
In very cold environments, it may be necessary to give the tool a slight amount of heat cure before it is removed from the pattern to avoid distortion due to insufficient cure. A few hours at 100°F to 150°F, depending upon what temperature the pattern material can withstand, will harden the tool to the point where it can be given an unsupported post cure. The lower the curing temperature that is used, the longer the curing time should be.


Gallon Kit
Pail Kit
Drum Kit
PT2520 A
9 lb.
40 lb.
470 lb.
PT2520 B
1.48 lb.
6.5 lb.
75 lb.
PT2520 B1
1.72 lb.
7.6 lb.
90 lb.

Inasmuch as PTM&W Industries, Inc. has no control over the use to which others may put material, it does not guarantee that the same results as those described herein will be obtained. The above data was obtained under laboratory conditions, and to the best of our knowledge is accurate. This information is presented in good faith to assist the user in determining whether our products are suitable for his application. No warranty or representation, however is intended or made, nor is protection from any law or patent to be inferred, and all patent rights are reserved. Before using, user shall determine the suitability of the product for his intended use, and user assumes all risk and liability whatsoever in connection therewith. In no event with PTM&W Industries, Inc. be liable for incidental or consequential damages. Buyer’s sole and exclusive remedy in such instances shall be limited to replacement of the purchase price.

 PT2520 A/B
PT2520 A/B1ASTM Method
Mix Ratio, by Weight
100 : 16
100 : 19
Mixed Viscosity, @77°F, centipoise
1900 cps
1275 cps
Working Time, 4 fl. oz. Mass @ 77°F
45 – 50 min.
4 – 4.5 hr.
Cured Hardness, Shore D
88 Shore D
88 Shore D
Specific Gravity, grams, cc
Density, lb./cu. in.
Specific Volume,  cu. in./lb.
Tensile Strength, psi 
36,680 psi
34,377 psi
Elongation at Break, %
1.79 %
1.55 %
Compressive Strength, psi
15,120 psi
15,773 psi
Glass Transistion Temperature, DMA:


PTM&W epoxy products are made from raw materials carefully chosen to minimize or even eliminate toxic chemicals, and therefore offer the user high performance products with minimum hazard potential when properly used.  Generally, the PTM&W epoxy resins and hardeners will present no handling problems if users exercise care to protect the skin and eyes, and if good ventilation is provided in the work areas.  However, all epoxy resins and hardeners can be irritating to the skin, and prolonged contact may result in sensitization; and breathing of mist or vapors may cause allergenic respiratory reactions, especially in highly sensitive individuals.  As such, avoid contact with eyes and skin, and avoid breathing vapors.  Wear protective rubber apron, clothing, gloves, face shield or other items are required to prevent contact with the skin.  In case of skin contact, immediately wash with soap and water, followed by a rinse of the area with vinegar, and then a further wash with soap and water.  The vinegar will neutralize the hardener and lessen the chances of long term effects.  Use goggles, a face shield, safety glasses or other items as required to prevent contact with the eyes.  If material gets into the eyes, immediately flush with water for at least 15 minutes and call a physician.  Generally, keep the work area as uncluttered and clean as possible, and clean up any minor spills immediately to prevent accidental skin contact at a later time.  Keep tools clean and properly stored.  Dispose of trash and empty containers properly.  Do not use any of these types of products until Material Safety Data Sheets have been read and understood.