What are the main components of OP-7 octylphenol polyoxyethylene ether?

The main component of OP-7 is octylphenol polyoxyethylene (7) ether (CAS: 9036-19-5), a nonionic surfactant formed by the addition polymerization of octylphenol with 7 ethylene oxide (EO) units.

Detailed Description

The full chemical name of OP-7 is octylphenol polyoxyethylene (7) ether, belonging to the alkylphenol polyoxyethylene ether (APE) class of nonionic surfactants. Its molecular formula can be expressed as C₈H₁₇C₆H₄O(CH₂CH₂O)₇H, with an average ethylene oxide addition number (n value) of 7 and a molecular weight of approximately 514 g/mol. The effective active content in the product is as high as ≥99%, with free alcohol content controlled within ≤1%, making it a high-purity industrial-grade surfactant raw material.

From a structural perspective, the OP-7 molecule consists of three parts: the hydrophobic end is the octylphenol group (octyl-substituted benzene ring), providing affinity for oils and organic solvents; the hydrophilic end is the polyoxyethylene chain segment (7 EO units), imparting water solubility and surface activity; the two are connected via an ether bond, giving the molecule both hydrophilic and lipophilic dual characteristics. This structure keeps the HLB value of OP-7 around 11.7, making it an emulsifier with moderate hydrophilic-lipophilic balance, possessing excellent wetting, penetration, emulsifying, and cleaning capabilities.

At room temperature, OP-7 appears as a colorless to light yellow transparent oily liquid, easily soluble in oils and various organic solvents, and can disperse and emulsify in water. The cloud point of the product ranges from 25 to 35°C; when the water temperature exceeds the cloud point, the nonionic surfactant precipitates from the aqueous solution, appearing turbid. The chemical nature of the product is weakly acidic to neutral (pH 5.0~7.0 for a 1% aqueous solution), showing excellent stability against acids, alkalis, and hard water ions, with no adverse reactions to conventional additives.

Technical Parameters

Application Recommendations

With its 99% high active content and moderate HLB value, OP-7 excels in the following areas:

• Industrial and household liquid detergents: Used as a high-efficiency wetting and cleaning component, recommended for dishwashing detergents and hard surface cleaner formulations.
• Textile industry: Applied in pretreatment processes such as desizing, scouring, and bleaching of grey fabrics, providing excellent washing, degreasing, and leveling effects.
• Pesticide emulsifiers: Promotes stable dispersion of active substances in water emulsions, microemulsions, and emulsifiable concentrate formulations, improving the spreadability of the spray solution.
• Emulsion polymerization: Used as a high-efficiency emulsifier and stabilizer for monomers in acrylic, styrene-acrylic, and vinyl acetate-acrylic systems.
• Metal cleaning and processing: Applied in acid/alkaline metal surface degreasers and metalworking fluids such as cutting fluids and grinding fluids.
• Paper and leather industry: Accelerates the penetration of cooking liquor and promotes the removal of resin and grease substances.

Precautions

Although OP-7 contains no other functional additive components and is essentially a high-purity octylphenol polyoxyethylene (7) ether substance, care should still be taken during use: The product is irritating to skin and eyes (GHS classification: Skin irritation category 2, Eye irritation category 2A). Protective gloves and goggles should be worn during operation. The product is toxic to aquatic life and must not be discharged into water bodies. It is recommended to store at temperatures between 5~35°C; at low temperatures, it may appear turbid or solidify, but it can recover upon returning to room temperature without affecting usage quality.