Eastman Hydroquinone Inhibitors for Polymerization
Eastman Hydroquinone & Derivatives
Eastman Chemical Company produces a series of in-process and storage inhibitors that stop or slow down free radical polymerization. These inhibitors are crucial in maintaining the integrity and stability of various monomers and polymers during manufacturing and storage. By preventing unwanted polymerization, these compounds ensure that products have a longer shelf life, are tailored to meet specific application requirements, and reduce the risk of hazardous reactions.
The Inhibitor Mechanism
Polymerization is initiated by free radicals. The function of polymerization inhibitors is to react with these free radicals to form stable compounds. This inhibition process slows down or stops polymerization. Inhibitors play an important role in the production and storage stability of various monomers and polymers, including vinyl monomers, acrylic monomers, and unsaturated polyesters. By curbing premature polymerization, these inhibitors not only extend the shelf life of monomer solutions but also safeguard against undesirable reactions during storage. Additionally, they provide precise control over reaction rates, ensuring manufacturers achieve the desired molecular weight and polymer properties necessary for high-quality end products.
Polymerization Inhibitors
Hydroquinone, phenolic compounds, and amines are common types of inhibitors used in polymerization. Hydroquinone is widely preferred in many processes due to its effectiveness at quenching free radicals and stabilizing monomers and polymers. Hydroquinone works in the presence of oxygen. Oxygen molecules react with free radicals to form peroxy-free radicals. Subsequently, hydroquinone's rapid reaction with peroxy-free radicals forms a free radical complex, which then interacts with another peroxy-free radical to yield stable compounds. The inhibitor mechanism of hydroquinone makes it indispensable in securing the integrity of various polymer systems during their lifecycle. Hydroquinone and its derivatives are especially important in controlling the cure characteristics of unsaturated polyester and vinyl monomer blends. Inhibitors, or often a combination of inhibitors, are selected based on their ability to prevent gelation during esterification and blending, impart long shelf life, aid in adjusting gel time, and control cure time. Listed below are the attributes of Eastman's hydroquinone inhibitors.
Hydroquinone (HQ)
Hydroquinone (HQ) is an excellent general-purpose inhibitor, stabilizer, antioxidant and intermediate chemical. Hydroquinone is commonly used in-process to stop free-radical polymerization, as well as an intermediate to make other inhibitors, stabilizers, antioxidants, agricultural chemicals, and dyes.
2,5-Di-tertiary-butylhydroquinone (DTBHQ)
2,5-Di-tertiary-butylhydroquinone (DTBHQ) is a multipurpose inhibitor, antioxidant, and stabilizer. DTBHQ can be used with other inhibitors as a storage inhibitor for unsaturated polyesters. It is also a useful antioxidant for rubber and an antiskinning agent in paint, as well as a stabilizer in various materials to prevent odor and color development.
Mono-tertiary-butylhydroquinone (MTBHQ)
Mono-tertiary-butylhydroquinone (MTBHQ) is a superb storage inhibitor for unsaturated polyesters, extending the shelf life and storage stability of the polymer. It is also an effective antioxidant for nonfood fats, oils, and unstable organic solvents.
INHIBITORS for…
HQ
MTBHQ
DTBHQ
Vinyl monomers
X
X
X
Acrylic monomers
X
X
X
Unsaturated polyesters
X
X
X
Peroxides in solution
X
X
Polymerization inhibitors are integral in upholding the quality and reliability of polymer products across various industries, from plastics to paints, dyes, and much more. Eastman is a U.S. based, world-class producer of hydroquinone and other resin intermediate products. Contact us to today to speak with a technical specialist and request a sample!