Synthesis Method and Application of Polysiloxane Guaternary Ammonium Salt

May 28, 2021

The organopolysiloxane quaternary ammonium salt is generally synthesized by the method of first synthesizing polysiloxane and then quaternizing. When synthesizing organopolysiloxane, the method of cyclosiloxane ring-opening equilibrium polymerization is generally adopted. , The catalyst has H2SO4, KOH, (CH3)NOH, etc., and then receives functional groups (such as amine groups), and controls the amount of access groups as needed, and then performs quaternization.

 Quaternization of hydrogen-containing silicone oil.The quaternary ammonium salt of polysiloxane can be obtained by polymerization of polysiloxane and hydrophilic substance, such as hydrogen-containing silicone oil, allyl alcohol, unsaturated polyethers with different relative molecular masses, one-- Using chloroacetic acid and tertiary amine as raw materials, through catalytic hydrogenation, esterification, and quaternization, a comb-shaped structure of polyether quaternized polysiloxane can be obtained. Zhou Yupeng et al. _ Il With hydrogen-containing polysiloxane and allyl alcohol, Polyoxyethylene allyl ether undergoes hydrosilation reaction, then esterification reaction with chloroacetic acid, and finally quaternization reaction with tertiary amine to prepare polysiloxane quaternary ammonium salt for shampoo

The agent began in the 1960s. In the 1970s, various modified organopolysiloxanes were added to the ranks of softeners. The amino group has polarity and can interact with the hydroxyl and carboxyl groups on the fiber surface to make the siloxane main chain directional. Attached to the surface of the fiber, the friction coefficient between the fibers is reduced, and a small force can start to slide between the fibers, so as to achieve an excellent soft and smooth effect. Amino groups have a strong affinity for the fibers and can Promote the oriented arrangement of organosilicon molecules, minimize the friction between the fibers, and improve the softness of the fibers; its biggest disadvantage is that it is easy to make light-colored fabrics yellow during the finishing process, which is generally believed to be caused by the oxidation of amino groups.

To overcome the above shortcomings, people often
The method is to modify its chemical structure. Modification methods include acylation modification, epoxy compound modification, formation of quaternary ammonium salt, etc. Organic silicon quaternary ammonium salt makes the nitrogen atom positively charged, reducing the oxidation of Sichuan energy When used for fabric treatment to achieve the anti-yellowing day, the silicone quaternary ammonium salt is combined with the fiber in two ways: one is that the positive center N in the molecule is attracted by the negatively charged fiber surface, which is a kind of electrostatic bonding. At the same time, molecular dehydration condensation is carried out to form a covering film on the surface of the fiber: another way is to combine the alcohol group produced by the hydrolysis with the hydroxyl group on the fiber surface under the high temperature condition of 120"C, and at the same time carry out the intermolecular dehydration condensation to make the molecules It is firmly bonded to the surface of the fiber by covalent bonds. Therefore, in practical applications, silicone quaternary ammonium salts are simultaneously formed by covalent bonds and electrostatic adsorption.

 Shampoo:The main function of shampoo is to wash off the oil and dust on the hair, while keeping the hair soft, shiny, and healthy. The main raw material for cleaning is various anionic surfactants and non-ionic surfactants; it can maintain Hair soft and shiny substances are also called conditioners, including various oils, fatty alcohols, polyquaternium polysiloxanes, and various oils (including methyl silicone oil) because they have no active groups, they are basically washed away by water after washing. , Poor conditioning. The macromolecule of polysiloxane quaternary ammonium salt contains hydrophobic long-chain polysiloxane, which makes it have excellent smoothness, softness and good gloss; at the same time, it contains positive charge The quaternary ammonium salt has electrostatic attraction with negatively charged hair, so it is washable and has excellent conditioning. It can significantly reduce the friction coefficient between hair and fiber, hair and comb, thereby greatly improving the dry and wet combing of hair It gives the hair a soft and smooth feel and increases the luster of the hair. It controls the structure of the polysiloxane quaternary ammonium salt so that it does not affect the foam of the shampoo; it has no irritation to human skin and eyes; it is resistant to gram-positive bacteria, Negative bacteria have strong bacteriostasis and bactericidal abilities.