From natural products to polymeric derivatives of “Eugenol”: a new approach for preparation of dental composites and orthopedic bone cements

摘要

Polymers with eugenol moieties covalently bonded to the macromolecular chains were synthesized for potentialudapplication in orthopedic and dental cements. First, eugenol was functionalized with polymerizable groups. Theudsynthetic methods employed afforded two different methacrylic derivatives, where the acrylic and eugenol moietiesudwere either directly bonded, eugenyl methacrylate (EgMA), or separated through an oxyethylene group,udethoxyeugenyl methacrylate (EEgMA). A typical Fisher esterification reaction was used for the synthesis of EgMAudand EEgMA, affording the desired monomers in 80% yields. Polymerization of each of the novel monomers, atudlow conversion, provided soluble polymers consisting of hydrocarbon macromolecules with pendant eugenoludmoieties. At high conversions only cross-linked polymers were obtained, attributed to participation of the allylicuddouble bonds in the polymerization reaction. In addition, copolymers of each eugenol derivative with ethyludmethacrylate (EMA) were prepared at low conversion, with the copolymerization reaction studied by assumingudthe terminal model and the reactivity ratios determined according to linear and nonlinear methods. The valuesudobtained were rEgMA ) 1.48, rEMA ) 0.55 and rEEgMA ) 1.22, rEMA ) 0.42. High molecular weight polymers andudcopolymers were obtained at low conversion. Analysis of thermal properties revealed a Tg of 95 °C for PEgMAudand of 20 °C for PEEgMA and an increase in the thermal stability for the eugenol derivatives polymers andudcopolymers with respect to that of PEMA. Water sorption of the copolymers was found to decrease with theudeugenol derivative content. Both monomers EgMA and EEgMA showed antibacterial activity against Streptococcusudmutans, producing inhibition halos of 7 and 21 mm, respectively. Finally, cell culture studies revealed that theudcopolymers did not leach any toxic eluants and showed good cellular proliferation with respect to PEMA. Thisudstudy thus indicates that the eugenyl methacrylate derivatives are potentially good candidates for dental andudorthopedic cements.