[Synthesis and characterization of dihydroeugenol acrylate]

Dihydroeugenol acrylate was synthesized by the reaction of acryloyl chloride (AC) with lignin mode compound dihydroeugenol (DH) in the presence of TEA and characterized by using FTIR, GC/MS, 1H-NMR and GPC. FTIR spectra showed that, after the esterification with acryloyl chloride, the intensity of stretching vibration peak of O-H (centered at 3 495 cm(-1)) of DH was disappeared. At the same time, a new peak appeared at 1 762 cm(-1) which was assigned to ester group. Additionally, the appearance of 1 631 and 981 cm(-1) were attributed to the carbon - carbon double bond confirmed the success in the synthesis of DH-AC. 1H-NMR spectra showed that, after the esterification with acryloyl chloride, the proton signal of O-H at 5.5 ppm was disappeared. Meanwhile, the appearance of three new proton signals at 6.0 ppm, 6.4 and 6.7 ppm, attributed to the vinylic protons, indicated that acryloyl chloride was successfully grafted onto DH. The results further confirmed the structures of the DH-AC. GC-MS results showed the DH-AC had a high purity of 98.63%. GPC results showed that dihydroeugenol acrylate could polymerize in the 1,4-dioxane using a thermal initiator of AIBN (2.0 Wt% of total monomers). The weight average molecular mass (Mw) of the homopolymer is 37 400 g x mol(-1), and the number average molecular mass is 23 400 g x mol(-1)' with a polydispersity index Mw/Mn of 1.60, indicating that the dihydroeugenol acrylate has high polymerization activity. This strategy provides a novel approach for extending the comprehensive utilization of lignin.