OP-21 (octylphenol ethoxylate (21) EO) is a high-performance nonionic surfactant produced by Guoli Chemical, manufactured through the addition polymerization of octylphenol with ethylene oxide. It appears as a white to light yellow waxy paste. With its outstanding emulsifying ability, excellent wetting and penetration properties, efficient dispersion and cleaning performance, as well as resistance to strong acids, alkalis, and hard water, OP-21 is widely used as a multifunctional additive in numerous industrial fields, representing a typical "industrial general-purpose" surfactant product.
The core advantage of this product lies in its nonionic nature—it does not dissociate in solution and exhibits excellent compatibility with anionic, cationic, and amphoteric surfactants, allowing OP-21 to be flexibly formulated into various systems. At the same time, its high active content (high concentration of active ingredients) means that the dosage can be reduced in practical use, thereby lowering overall costs and offering significant economic benefits.
It is particularly important to note that the octylphenol group contained in OP-21 has certain persistence in the environment and may cause long-term adverse effects on aquatic organisms. Therefore, during use and waste disposal, relevant environmental regulations must be strictly followed, and wastewater containing this product must not be discharged directly into water bodies.
| Industry | Application Process\/Stage | Function |
|---|---|---|
| Textile Printing and Dyeing | Pretreatment scouring, dyeing leveling, fiber penetration | Used as a penetrant, scouring agent, and leveling agent to improve uniformity of fiber treatment and dye uptake rate, suitable for cotton, synthetic fibers, and blended fabrics |
| Leather Processing | Degreasing process, fatliquoring process | Helps remove natural fats from hides, promotes uniform penetration of fatliquoring materials, and improves leather softness and feel |
| Papermaking Industry | Pulping, waste paper deinking | Acts as a wetting and dispersing agent to accelerate ink detachment and dispersion during waste paper repulping, promote fiber separation, and improve deinking efficiency |
| Detergent Industry | Household detergents, industrial detergents, hard surface cleaners | Provides detergency, emulsification, and wetting capabilities, effective in removing various types of oily soils |
| Pesticide Formulations | Preparation of emulsifiable concentrates (EC), emulsion in water (EW) | Acts as a highly effective emulsifier to ensure rapid dispersion of active ingredients in water and formation of stable emulsions, enhancing dilution stability and efficacy |
| Coatings and Inks | Pigment dispersion, color paste preparation | Functions as a pigment dispersing and wetting agent to shorten grinding time, prevent pigment particle flocculation, improve storage stability, and color development |
| Emulsion Polymerization | Full polymerization process | Acts as an emulsifying stabilizer to ensure stable dispersion of monomer droplets and polymer latex particles, control particle size, and optimize emulsion performance |
| Metalworking Fluids | Cutting fluids, degreasers, rust preventives | Enhances cooling, lubrication, and cleaning performance, effectively removes mineral oils and animal\/vegetable fats, and provides synergistic anti-corrosion effects |
In formulation design, OP-21 is recommended to be used as a primary or auxiliary emulsifier. With a high HLB value (approximately 15-16, due to the long EO chain structure), it is particularly suitable for constructing O\/W (oil-in-water) emulsion systems. In textile scouring agent formulations, it is advisable to blend with anionic surfactants to achieve synergistic effects. In pesticide emulsifiable concentrate formulations, the conventional dosage is 5% to 15% of the active ingredient weight. In coating color paste dispersion, the recommended dosage is 2% to 8% of the pigment weight. Specific dosages should be determined through experiments based on the actual formulation system and process conditions.