Rich in a variety of saturated/unsaturated fatty acids, minerals and vitamins, vegetable oils are believed to improve hair softness, antioxidants and repair damaged keratin. At present, some studies have reported the permeability of pure vegetable oil in hair and the corresponding effect of hair care. However, vegetable oil has some problems such as high cost, easy oxidation and poor compatibility, and is often added in trace form, which limits its actual effect. Compared with vegetable oil, the research and application of silicone oil in personal care products is very mature. In order to improve the convenience of the formulation process and the stability of the product, silicone oil is often added to the formulation system in the form of emulsion, which spreads out into a film during the rinsing process, and ultimately improves the smoothness and anti-static properties of the hair. Silicone oil, as a macromolecular polymer, mainly improves the surface properties of hair and is difficult to enter the hair to provide damaged repair.

Good permeability is the first condition for vegetable oil to play a unique role. In order to meet consumers' increasing preference for natural ingredients and their demands for the multi-efficacy of products, it is necessary to explore a technical solution for the synergy and complementarity of vegetable oil and silicone oil, which can not only improve the efficacy and dosage of vegetable oil, but also maintain the unique regulation of silicone oil, so as to achieve the multiple effects of internal and external care. Chinese researchers have developed a test method to characterize the permeability of vegetable oil using hydrogen NMR spectroscopy. According to the signal peak of fatty acid triglyceride and the integral area of vegetable oil, the permeability of 4 kinds of vegetable oil (coconut oil, olive oil, sunflower oil, argin) was studied. The best permeable coconut oil and silicone oil were blended and emulsified to prepare a "three-in-one" emulsion (coconut oil, ammoniac-terminated polydimethylsiloxane, polydimethylsiloxane). The properties of the emulsion were tested by NMR, carding force test and sensory evaluation.

The results showed that coconut oil has excellent permeability and can be co-emulsified with silicone oil to form a stable and multi-care "three-in-one" emulsion (coconut oil, ammoniac-terminated polydimethylsiloxane, polydimethylsiloxane). During the application of the emulsion, coconut oil can effectively penetrate the hair scales and improve hair flexibility from the inside. After the large molecular silicone oil is spread on the surface of the hair, it can make the hair have a smoother tone and a gentle touch. Compared to the combination of silicone oil emulsion and coconut oil separately, the "three-in-one" emulsion showed better synergy in both grooming power and sensory evaluation.