Hydroquinone Dihydroxyethyl Ether

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Abbreviation: HQEE

Synonyms: Hydroquinone bis(2-hydroxyethyl) ether, Hydroquinone Dihydroxyethyl Ether, Hydroquinone-bis(2-hydroxyethyl) ether, 1,4-Di(2-hydroxyethyl)hydroquinone, 1,4-Di(2-hydroxyethoxy)benzene.

Molecular Formula: C₁₀H₁₄O₄

Molecular Weight: 198.2

CAS Number: 104-38-1

EINECS Number: 203-197-3

Structural Formula:

Physicochemical Properties:

White to off-white powder or flaky solid, hygroscopic. The flaky product absorbs 0.39% moisture after being placed at 24°C and 66.5% relative humidity for 168 hours. T

HQEE is sensitive to light; it turns yellow or brown under ultraviolet light. HQEE is virtually non-toxic, with an acute oral toxicity LD50 in rats > 5 g/kg.

Properties and Uses:

HQEE is a symmetrical aromatic diol chain extender that improves the rigidity and thermal stability of polyurethane elastomers. It is non-toxic and non-irritating.

HQEE is primarily used as a chain extender for polyurethane elastomers. It can be used as a crosslinking agent for compounded, cast, and thermoplastic polyurethane elastomers, improving product stability and enhancing various properties such as tear strength, heat resistance, hardness, resilience, and compression set. It is particularly suitable for MDI series products, exhibiting good compatibility with MDI, effectively extending in-melt life, and facilitating operation.

During polyurethane elastomer production, the HQEE melting vessel should be equipped with heating and gentle stirring devices to prevent surface film formation. Throughout the entire production process, the temperature of both the prepolymer and HQEE should be controlled above 110℃ to prevent crystallization that could clog the production line or cause inaccurate mixing ratios. The mold temperature should also be maintained above 110℃ to avoid defects in the elastomer. The recommended molar ratio of NCO/OH is approximately 1.1/1 to avoid moisture absorption.