MEKP (Methyl Ethyl Ketone Peroxide) is the catalyst added to polyester resins and vinyl ester resins. As the catalyst mixes with the resin, a chemical reaction occurs, creating heat which cures (hardens) the resin.

How long does MEKP catalyst last?

Description. This MEKP is the catalyst/hardening agent for polyester resins and polyester gelcoats. This item has a shelf life of approximately 2-3 months. One gallon will cure approximately 100 gallons of resin and 50 gallons of gelcoat.

Is MEKP toxic?

Methyl Ethyl Ketone Peroxide (MEKP) is a highly toxic clear liquid used as a solvent. It is a strong oxidizing agent and a corrosive. Acute and chronic toxicity can occur as an occupational hazard.

What does MEKP stand for?

Methyl ethyl ketone peroxide (MEKP) is an organic peroxide with the formula [(CH3)(C2H5)C(O2H)]2O2. MEKP is a colorless oily liquid. It is widely used in vulcanization (crosslinking) of polymers. It is derived from the reaction of methyl ethyl ketone and hydrogen peroxide.

Is MEKP a VOC?

MEKP is a highly reactive, colorless liquid organic oxidizer, with a pungent burning odor, which has the following properties: … Therefore, the normal usage of MEKP at reinforced plastics facilities will not result in any measurable VOC or HAP emissions whatsoever.

Does fiberglass resin have a shelf life?

A lot of manufacturers/suppliers recommend not using resin if its older than 6 months.

Does MEKP catalyst go bad?

If you catalyze a batch of polyester resin use half brand new and half old MEKP. Even if the old MEKP has decomposed and lost 20% or so of its strength it should still work ok.

How much Mekp is polyester resin?

POLYESTER RESIN/GELCOAT IS CATALYZED WITH MEKP (METHYL ETHYL KETONE PEROXIDE). THE RATIO IS APPROXIMATELY ONE OUNCE OF HARDENER PER GALLON OF RESIN.

Is Mekp explosive?

MEKP is an organic peroxide, a high explosive similar to TATP, and is very dangerous to prepare.

What is Mekp hardener?

MEKP (Methyl Ethyl Ketone Peroxide) is a catalyst used in the composites industry for polyester and vinyl ester resins and gel coats. It reacts with the resin to turn it from a liquid to a solid (cure it). It is used in varying ratios, generally between 1%-3%, depending on the product being used.

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What is the pH of Mekp?

MEKP is a strong oxidizing agent. MEKP is hydrolytically stable over a range of environmentally relevant pH and temperature conditions (half-lives of 204, 1155, and 224 hours at 25°C and pH 4.0, 7.0 and 9.0, respectively) following OECD TG 111.

Is all Mekp the same?

The one limiting factor is that all MEKP manufacturers are limited, by law, to a maximum content of active ingredients in a given formulation. The inactive ingredients, or diluents, consist of DMP, dimethyl phthalate, and/or TXIB, safety solvents, and small amounts of water, MEK, and glycol.

What are the side effects of methyl ethyl ketone?

* Breathing Methyl Ethyl Ketone can irritate the nose and throat causing coughing and wheezing. * Exposure can cause dizziness, lightheadedness, headache, nausea, blurred vision, and may cause you to pass out. * Repeated high exposure can damage the nervous system and may affect the brain.

What is the catalyst for polyester resin?

MEKP (Methyl Ethyl Ketone Peroxide) is the catalyst added to polyester resins and vinyl ester resins. As the catalyst mixes with the resin, a chemical reaction occurs, creating heat which cures (hardens) the resin. Use approximately 1/2 oz per quart of resin.

How much catalyst do I need for polyester resin?

A rule of thumb for polyester laminating resin is between 1% and 2% i.e. 1% for summer (to give maximum wetting time) and 2% for winter. For polyester Gelcoats used in a moulding situation, we recommend from 2% to 2.5%catalyst.

Is MEK banned?

MEK is a popular chemical solvent used across several industries including ink, varnishes, and paint, but has MEK been banned? The answer is no. … In fact, MEK is even approved by the FDA for indirect food processes, such as use as an additive for adhesives and polymers.

Can you put fiberglass resin over wood?

Fiberglass resin can seal wood to form a shell that protects the wood, and provides a smooth painting surface. It also fills in any imperfections. Glassing over wood requires a few precautions and techniques to ensure uniformity, strength and bonding.

How long does vinyl ester resin last?

The primary shortcoming is their limited shelf life, many vinyl ester resins only have a 3 month shelf life. This means you typically have to order as needed for a given project rather than stocking up. They are also more expensive than polyester resins and do not offer the ultimate strength that epoxy resins do.

How do you dispose of MEKP?

Wet the MEKP with water, and then sweep into clean polyethylene bags and transfer to disposal area. Dispose in accordance with Federal, State and local regulations. MEK Peroxide is specifically listed as a Hazardous Waste in 40CFR Part 261.33, with an EPA Waste No. of U160.

How long does resin last once opened?

If the bottles remain unopened, ArtResin has a shelf life of 12 months from the date of manufacture. Once the bottles have been opened, however, the shelf life is 6 months from the date of manufacture.

Will old fiberglass resin harden?

There are few things worse than having finished a large project using fiberglass, only to not have it fully cure. You let it sit, and sit, and sit, but it never completely hardens. Chances are you did not add enough catalyst, the chemical that hardens the resin.

What does fiberglass resin do?

Fiberglass resin is used to repair the bodies of cars and boats. Completed, dry fiberglass resin is made of fiberglass cloth bonded to the car or boat with resin and a catalyst, to make the resin harden.

How is methyl ethyl ketone peroxide made?

The invention provides a kind of method that use acid-exchange resin makees catalyst preparation methyl ethyl ketone peroxide, it is using butanone and hydrogen peroxide as raw material, catalyst is made with acid-exchange resin, using dibutyl phthalate as diluent, after constant temperature stirring reaction, standing …

Can I use hydrogen peroxide?

The Food and Drug Administration (FDA) classifies hydrogen peroxide as “generally recognized as safe” (GRAS) for humans at low doses. But the FDA warns that getting hydrogen peroxide on your skin may cause irritation, burning, and blistering.

How explosive is MEK?

METHYL ETHYL KETONE is explosive in the form of vapor when exposed to heat, flame or sparks. Ignition on contact with potassium tert-butoxide. Reactive with strong oxidizing materials, and will dissolve or soften some plastics. Mixture with 2-propanol will form explosive peroxides during storage.

How many drops of MEKP is 1 oz of gelcoat?

We recommend 1.5% – 2.0 % by volume. The Ideal range is 1.8% @ 77°F (approximately 12 drops per ounce of gelcoat.)

What happens if you put too much catalyst in resin?

Adding too much of either resin or hardener will alter the chemical reaction and the mixture will not cure properly.

How do you mix polyester resin and MEKP?

TotalBoat Polyester Laminating Resin requires the adding of MEKP catalyst at the ratio of 7-8 drops of MEKP per one ounce of resin at 77°F (1. 0-2.2% MEKP based on the weight of the resin). Mix thoroughly for at least one minute and apply immediately after.

How do you store MEKP?

MEKP should be stored in the original closed container in a cool place away from all sources of heat, sparks, or flames, and out of direct sunlight. Exposure to high temperatures or contamination with foreign materials may result in explosive decomposition. Do not store in unvented glass containers.

How much catalyst can I mix with resin?

Fibreglass Resin: for 100ml of resin (cold day) use 2.5 to 3ml catalyst; and for 100ml resin (hot day) use 1.5 to 2ml catalyst.

How many drops of resin are in an ounce of MEKP?

To catalyze TotalBoat Polyester Laminating Resin, at 77°F, add 7-8 drops of MEKP catalyst per one fluid ounce of resin. You can measure the fluid ounce(s) of resin in a clean mixing cup.