Isophthalic Polyester Resin

4.9 star rating

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  • Item
  • Description
  • Price
  • Qty
  • 90/69-F
  • 90/69-F
    Quart w/ hardener
  • $54.95
  • 90/69-A
  • 90/69-A
    Gallon w/ hardener
  • $109.95
  • 90/69-AK
  • 90/69-AK
    Case (4 Gallons w/ hardener)
  • $399.95

  • 90-F
  • 90-F
    Quart (2 lbs)
  • $49.95
  • 90-A
  • 90-A
    Gallon (9 lbs)
  • $104.95
  • 90-B
  • 90-B
    5 Gallon Pail (40 lbs)

    Quantity Discounts

  • $399.95


Build Strength and Stability for Tough Parts

#90 Isopthalic Polyester is perfect for fabricating dimensionally stable polyester molds and corrosive service parts. It is often used as a durable repair material for tank linings. This Iso polyester resin offers fast wet-out in spray-up or hand laminates. When spraying, we recommend using a 18" nozzle. The 225 degree F service temperature resists exotherm and post cure problems. #90 Isophthalic Polyester Resin has better strength properties than a general purpose polyester resin, which allow it to be used in more demanding applications.

Properly fabricated parts may be used in food contact, electrical and military applications.

#90 Isopthalic Polyester resin is formulated for 1.25% MEKP catalyzation. This resin can be purchased alone or as part of a Resin and Hardener Kit.

#90/69-F kit contains (1) QUART RESIN, (1) #69-A.

#90/69-A kit contains (1) GAL RESIN, (2) #69-A.

#90/69-AK kit contains (4) GAL RESIN, (8) #69-A.

warning WARNING: This product can expose you to chemicals including Styrene which is known to the State of California to cause cancer. For more information go to


Isophthalic Polyester Resin quart (#90-F) and gallon (#90-A) units and kits can be shipped via standard ground service without hazard charges within the 48 contiguous United States. 5-gallon quantity (#90-B) is considered hazardous (flammable) and will be subject to a hazard charge if shipped by standard ground. All sizes of #90 (quart, gallon, and 5-gallon) will be subject to a hazard charge if shipped by air. Please see our Hazardous Shipping Chart for more information about hazard fees. We will consolidate items whenever possible to minimize these fees.


Isophthalic Molding Resin This resin is available in a variety of sizes that include: One quart (#90-F) One gallon (#90-A) A five-gallon pail (#90-B) One drum (#90-DRUM) *Quantity discounts are available on the five-gallon pail only, when four or more units are ordered at one time. This resin can be purchased as part of a kit that includes MEKP catalyst. You should purchase the kit unless you already have hardener in your workshop. The kits include: One quart of resin, with one 1 oz. bottle of hardener (#90/69-F) One gallon of resin, with two 1 oz. bottles of hardener (#90/69-A) One case of four gallons, with eight 1 oz. bottles of hardener (#90/69-AK)


4.9 star rating

No title

Aug 1, 2022  |  By Edward

Fast delivery, well packaged, great product...

Precision racecars

Mar 31, 2021  |  By Joe Gambino

Service is great. Prices are fair. Great company. I will be using for all my comp needs

Precision racecars

Mar 31, 2021  |  By Joe Gambino

Service is great. Prices are fair. Great company. I will be using for all my comp needs
Mold building
Mar 3, 2018  |  By CLIFF DE LA CERDA
This product works great, as advertised. I used this resin for building my canoe mold. Can be used in cooler temps, highly recommended.

Iso polyester resin
Feb 11, 2018  |  By michael sherman
This was one of my smallest orders, using this to repair CenTek exhaust collector on a customers boat. Have used over 30 gallons of FibreGlast supplied resins in the past, always impressed by the high quality, ease of wet out and the tech support. Always feel bad for the people I see in the marine chain store,purchasing that jelly like, almost unusable stuff off the shelf.

Easy for this novice to use
Dec 14, 2016  |  By Jim
I bought the quart size for a small project. I like that the container is suited for pouring; other products I've used came in quart "paint-style" containers with a lip that makes it messy to pour, or dip. Instructions on the can include the amount of catalyst needed for 1 ounce of resin, which is what I sometimes need for small projects. Set time was as expected for the temperature.

Great product/Difficult online ordering
Aug 20, 2015  |  By Kate W
Your service is great, your product (isophthalic resin) was exactly what I needed and it came quickly. Your online purchasing was difficult, however. It is apparently not possible to purchase something and have it sent to an address other than the billing address - at least I couldn't figure out how to do it. I had to have the resin shipped to the account because her name was on the credit card - a minor but unnecessary inconvenience. The second time I tried to order from you, I couldn't figure out why your site wouldn't let me complete my order. Fortunately, your sales person was pleasant and efficient.

Polyester resins
May 29, 2015  |  By Phillip P
I was pleased to return to my favorite composite website and order my preferred resin for use in building giant scale model RC aircraft. You used to have a name for glass cloth compatible with epoxy and/or polyester resins. What happened to this important distinction?

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