Synthesis and characterization of a new dimethacrylate monomer based on 5,5′-bis(4-hydroxylphenyl)-hexahydro-4,7-methanoindan for root canal sealer application

In this study, a new dimethacrylate monomer 5,5′-bis[4-(2′-hydroxy-3′-methacryloyloxy-propoxy)-phenyl]-hexahydro-4,7-methan-oindan (5,5′-BHMPHM) with molecular weight of 640 and large molecular volume was designed and synthesized. The structure of monomer 5,5′-BHMPHM was confirmed by FT-IR, 1H-NMR and elemental analysis. Degree of double bond conversion, volume shrinkage, contact angle, water sorption and solubility, diffusion coefficient value, flexure strength and modulus of 5,5′-BHMPHM/tri(ethylene glycol) dimethacrylate (TEGDMA) based resin were measured. 2,2-bis[4-(2′-hydroxy-3′-methacryloyloxy-propoxy)-phenyl]-propane (Bis-GMA)/TEGDMA based resin was used as reference. The result illustrated that the double bond conversion, polymerization shrinkage, and diffusion coefficient value of 5,5′-BHMPHM/TEGDMA based resin were significantly lower than that of Bis-GMA/TEGDMA based resin (P < 0.05). Water sorption, solubility, flexure strength and modulus of 5,5′-BHMPHM/TEGDMA based resin were higher than that of Bis-GMA/TEGDMA based resin (P < 0.05). There was no statistical difference between 5,5′-BHMPHM/TEGDMA based resin and Bis-GMA/TEGDMA based resin in contact angle (P > 0.05).