Figure 2.

¹H nuclear magnetic resonance spectra of poly(NIPAM-co-SA) and PEGDMA.

Notes: ¹H nuclear magnetic resonance spectra of (A) poly(NIPAM-co-SA) and (B) PEGDMA. The triplets near 0.84 ppm in (A) indicate the presence of stearyl groups in the polymer backbone, representing that SA monomers were copolymerized with NIPAM. The chemical shifts of methylene protons on PEGDMA are 5.76 ppm and 6.18 ppm, and the protons next to the terminal MA group shifted to 4.37 ppm as shown in (B). Lowercase letter in by the peaks in the graph, correspond to the chemical groups.

Abbreviations: poly(NIPAM-co-SA), poly(N-isopropylacrylamide-co-stearyl acrylate); PEGDMA, polyethylene glycol dimethacrylates; SA, stearyl acrylate; NIPAM, N-isopropylacrylamide; MA, methacrylic anhydride.