สำนักราชบัณฑิตยสภา

97 Jaruwan Krongsin, Roongkan Nuisin, Supaporn Noppakundilograt, Suda Kiatkamjornwong วารสารราชบัณฑิตยสถาน ปีที่ ๓๗ ฉบับที่ ๔ ต.ค.-ธ.ค. ๒๕๕๕ Preparation of chitosan microcapsules via a double emulsion method The primary and secondary emulsions at a ratio of 1 : 1 were mixed and stirred gently at 200 rpm for 1 h. Sodium tripolyphosphate (TPP) crosslinking agent with a concentration of 5% was slowly dropped into the mixture of primary and secondary emulsions. The amino group of chitosan-to-TPP ratio was 2 : 1 and the pH was adjusted to 7. Finally, the chitosan/menthol microcapsules were collected and washed repeatedly thrice with petroleum ether and acetone by centrifugation at 3,000 rpm, and then the microcapsules were freeze dried. Preparation of leave-on hair conditioner The mixtures of conditioner base listed as the ingredients shown in Table I were mixed with deionized water at 70-80 º C , stirred at 400 rpm. The mixture was cooled to 40 º C , the glydant as a preservative and chitosan/menthol microcapsule emulsion were then added, and stirred until a homogeneous emulsion was obtained. The conditioner was left for 1 h for further experiments. OriginPro 8 was used to estimate the area of flow of microcapsule emulsion, conditioner base and the leave-on conditioner in order to observe its size with respect to flow.