PT2846 High Temperature Epoxy Laminating Resin


PT2846 is an amber, unfilled high temperature epoxy laminating resin designed specifically for demanding high performance composite tooling. PT2846 has good heat resistance, making it capable of providing excellent long term service in today’s higher temperature curing cycles. The resin has a medium-low viscosity, and, when combined with the hardeners recommended here, allows very easy handling in tool fabrication. The mixed systems wet out the tooling fabrics very readily. This allows faster tool production than when using more viscous materials. This feature is achieved without the use of hazardous or potentially restricted diluents. PT2846 does not contain vinylcyclohexane diepoxide (VCHD).

Three low toxicity hardeners are listed here for use with PT2846. These hardeners provide a broad range of working times for all sizes of tools and lay-up methods. All three hardeners give good high temperature performance with very high physical properties. These hardeners do not contain methylene dianiline (MDA), or other potentially harmful aniline derivatives. They are non-staining materials, and will not crystallize in normal shipping and storage conditions. Other hardeners with special characteristics are available for use with PT2846. Check with our Technical Services
department for details and recommendations.

Mix Ratio
Pot Life
PT2846 Part B
100 : 19
40 – 45 min.
 Intermediate high temperature service hardener with a shorter pot life for smaller tools. Provides a good hard gel at room temperature. Recommended for tools operating in the 275°F to 350°F range. Also, excellent for back-up structure attachment and quick repairs.
 PT2846 Part B1
100 : 22
2.5 – 3 hours
 Intermediate high temperature service hardener with longer working time than PT2846 Part B, for somewhat larger tools and vacuum bagging operations. PT2846 Part B1 gives a good gel at room temperature (77°F), and can allow an unsupported post cure to a properly gelled tool. It provides durable tools with good dimensional stability, for applications in the 300°F to 350°F range. This combination has a lower mixed viscosity for good fabric wetting.
PT2846 Part B2 100 : 9.5
3 – 4 hours
 A unique high temperature service, low toxicity hardener for the most demanding tooling applications. The longer working time allows vacuum bag fabrication of medium sized tools with excellent cured properties. PT2846 Part B2 can be gelled hard at 120°F or higher on a plastic faced plaster pattern for subsequent unsupported post cure and service to over 425°F

 PT2846 A
PT2846 B
PT2846 B1
PT2846 B2
ASTM Method 
7000 cps
1700 cps
500 cps
690 cps
Specific Gravity, gms./cc
Mix Ratio, by Weight

100 : 19
100 : 22
100 : 9.5
Pot Life, 4 fl oz Mass @ 77°F
40 – 45 min.
2.5 – 3 hr.
3 – 4 hr.


PT2846 Part B and Part B1: Hardeners PT2846 Part B and Part B1 have been designed to gel hard at room temperature, to allow removal of the laminate from the pattern after an overnight (18 to 24 hours) cure at room temperature, and then be given an unsupported post cure. PT2846 Part B1 has a longer pot life than PT2846 Part B, to allow vacuum bagging applications on smaller tools.

PT2846 Part B2: A unique feature of PT2846 Part B2 is that the heat resistance of the material “leads” the curing temperature. For example, castings of PT2846 Part B2 and PT2846 cured for 16 hours at 120°F have a heat deflection temperature of over 175°F. With the addition of four hours at 200°F, the heat deflection temperature of the casting is increased to over 250°F. Values for a laminate would be much higher due to the reinforcement of the fabric. This feature allows the fabrication of a high temperature laminate on a plastic faced pattern, and removal after an initial low temperature cure. It can then be post cured unsupported with full confidence that the finished tool will have excellent stability.

 PT2846 A/B
PT2846 A/B1
PT2846 A/B2
ASTM Method
Mix Ratio, by Weight
100 : 19
100 : 22
100 : 9.5
Mixed Viscosity, @77°F, centipoise
4000-4500 cps
3000-3500 cps
5100-5600 cps
Pot Life, 4 fl.oz. Mass, @77°F
40-45 min.
2.5-3 hr.
3-4 hr.
Cured Hardness, Shore D, @77°F, @300°F*
90, 86
92, 87
80 (*@350°)
Specific Gravity, grams, cc
Density, lb./cu. in.
Specific Volume,  cu. in./lb.
Tensile Strength, psi (Laminate)*
29,440 psi
30,880 psi
30,370 psi
Elongation at Break, % (Laminate)*
1.49 %
1.57 %
1.50 %
Tensile Modulus, psi (Laminate)*
50,303 psi
54,250 psi
69,730 psi
Flexural Strength, psi (Laminate)*
44,463 psi
47,649 psi
38,099 psi
Flexural Modulus, psi (Laminate)*
557,871 psi
801,525 psi
540,009 psi
Compressive Strength, psi (Cast Bar)
15,950 psi
17,100 psi
16,880 psi
Compressive Modulus, psi (Cast Bar) 138,040 psi
139,540 psi
138,820 psi
Glass Transistion Temperature, DMA:

*Tensile & Flexural Properties Determined with a 1/8” Laminate, Style 7500 Tooling Cloth, Resin Content of 50%-55%


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.