Amphiphilic graft copolymers were synthesized using chitosan with varying substitution degrees of methoxy polyethylene glycol and palmitic acid. FT‐IR, 1H‐NMR, differential scanning calorimetry, and elemental analysis showed successful chitosan modification. Amphiphilic copolymers are able to produce nano ssemblies with low critical micelle concentration (CMC). It was demonstrated that particle size (PS) analysis and drug solubilization methods could be used to determine CMC, beside fluorescent pyrene assay. Paclitaxel was efficiently loaded (up to 12.8%) without significant change in the nanomicelles’ PS. In addition, without significant change in size and loading, nanomicelles could be freeze‐dried. Hemolysis assay exhibited biocompatibility of copolymers and cell cytotoxicity assay on MCF‐7 cell line showing the encapsulated drug had a higher cytotoxic effect. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43233.