Anionic Surfactant Sulfate

Commonly used such active agents are fatty alcohol polyoxyethylene ether sulfate and sodium lauryl sulfate. The fatty alcohol polyoxyethylene ether sulfate is aliased to AES, sodium alcohol ether sulfate. It is easily soluble in water. When the active content is 70%, the appearance is light yellow viscous liquid (translucent), and the stability is lower than that of common sulfonate. It is hydrolyzed quickly below pH 4, but it has good hydrolysis stability under alkaline conditions.

Sodium lauryl sulfate is known as AS, K12, sodium cocoyl sulfate, sodium lauryl sulfate, and a blowing agent. It is soluble in water and has a solubility of about 15 in water at 25 ° C, but the degree of water solubility is inferior to AES. Insensitive to alkali and hard water, but less stable than ordinary sulfonates under acidic conditions, close to AES, long-term heating should not exceed 95 ° C, irritating in the middle layer of surfactant, 10% solution stimulation index 3.3, high At AES, lower than LAS.

AES can be used in shampoos, showers, dishwashing liquid detergents (detergents), and laundry liquid detergents. When applied, if the pH quality index allows, the pH should be adjusted as much as possible, such as neutral or alkaline. When AES must be used under low pH conditions (in shampoos), its ethanolamine salt is generally used. AES is more water soluble than AS, which can be formulated into any transparent aqueous solution at room temperature. AES is not only more widely used than LAS in liquid detergents, but also has better compatibility. It can be compounded with many surfactants or compounded into a transparent aqueous solution. Among the synthetic surfactants, AES has the third highest output and the price is lower than AS. In 2002, the 70% AES price was RMB8,500/t. The outstanding advantages of AES are small irritancy, good water solubility, good compatibility, and good performance in preventing dry skin cracking. The disadvantage is that the stability in the acidic medium is slightly worse - the pH must be controlled to be much greater than 4, and the detergency is second to LAS and AS.

When using AS in liquid detergents, it must be paid attention to the pH medium conditions - the acidity is not too high; the application in shampoo must use its ethanolamine or ammonium salt; in the shower liquid is often the use of its ethanolamine or ammonium salt . The use of its ethanolamine salt not only increases acid resistance stability, but also helps to reduce irritation. A 10% triethanolamine salt stimulation index of 3.0. AS is less frequently used in dishwashing liquid detergents, and is rarely used as a primary surfactant, ie, a small amount of formulation, which is mainly due to the disadvantage of reducing product cost, and secondly, such products have almost no requirement for foaming. Among the synthetic surfactants, AS has the fifth highest output and the price is high. In 2002, the powder price was RMB15,000/t. In addition to good foaming and detergency, AS is not as good at performance as AES. If the acid resistance is slightly worse, the irritancy is relatively large - just less than LAS, and the price is also the highest among common anionic surfactants.