Study On Synthesis Andapplication Of One New Polyquaternium For Hair Care Products

Increasing the concentration of cationic polymer to improve the conditioning properties of shampoo would reduce the foaming properties and increase the cost. To solve this problem, one cationic polyquaternium with the high cationic degree was designed and prepared in order to ensure the conditioning and foaming properties of shampoo.It took three steps to synthesis P(AM-co-NVI). Firstly, N-(3-chloro-2-hydroxypropyl)- N, N-dimethyldodecylammonium chloride (CHDDAC) was synthesized by N,N-dimethyl dodecylamine hydrochloride and epichlorohydrin as the raw materials. Secondly, the polymerizable gemini surfactant (NVI) was synthesized by CHDDAC and vinylimidazole. Lastly, P(AM-co-NVI) was prepared by the copolymerization of NVI and acrylamide (AM). The optimum reaction conditions of CHDDAC were as follows: n(ECH):n(tertiary amine hydrochloride)=1.05:1.0, the reaction temperature was 40℃, the reaction time was 4 hours, the content of active substance (chlorine hydroxypropyl) achieved 93.5%. The optimum reaction conditions of NVI were as follows: n(VI):n(intermediate product)=1.2:1.0, the reaction temperature was 80℃, the reaction time was 12 h. The yield of NVI was 80.7%. The optimum reaction conditions of P(AM-co-NVI) which had a high cationic degree and high viscosity were as follows: Under the condition of AM:NVI=8:1, the reaction temperature was 50℃, the concentration of monomer was 20%, the concentration of initiator was 0.3%, the reaction time was 5h. These structures were characterized by IR, MS, 1HNMR. NVI has a good surface activity. It can reduce the surface tension to 36.54 mN/m, and its cmc is 6.9×10-3 mol/L.From the study of P(AM-co-NVI), with the increasing concentration of polyquaternium, the foaming property of shampoo was reduced, and it would affect the performance of shampoo. P(AM-co-NVI) added into shampoo can suppply a moderate viscosity, have a good sense and appearance. P(AM-co-NVI) can improve the dry and wet combing, especially better than commercial products with a low concentration in wet combing.In summary, P(AM-co-NVI), one synthesized polyquaternium, can be applied in the shampoo formulation as a good conditoner and improve the dry and wet combing ability. And it has achieved the original intention of the designed molecular structure.