The invention relates to a monomer or mixture of monomers represented by the following structure with 1, 2 R independently selected from H, alkyl (e.g. CH 3 , C 2 H 5 ), CF 3 , and Phenyl 3, 4 R independently selected from H, alkyl (e.g. CH 3 ), and halogen (Cl, Br, F) 5 R independently selected from H, alkyl (e.g. CH 3 ) m, n = 1, 2 and x + y = 2 to 10. The invention also relates to a process for producing the monomer or mixture of monomers and the use thereof especially as dental composition.