1987 Volume 29 Issue 4 Pages 287-297
The present studies were carried out with the aim of developing monomers for dental resin, for which the authors synthesized 13 kinds of monomers with a P-N-bond skeleton, containing polymerizing groups and hydrophobic groups in the molecule.
The conditions of synthesis and the properties of the monomers were then examined and the results obtained were as follows :
1. Of the 13 kinds of synthesized monomer, PNC-EMA monomer showed a comparatively large unsubstituted chlorine value of 0.28, whereas the rest showed values between 0.04 and 0.17.
2. In the 2nd step of synthesis, it was possible to shorten the reaction time from 100h to 50 h by raising the reaction temperature from 50°C to 60°C, but even when the temperature was raised to 70°C, the amount of unsubstituted chlorine was almost the same.
3. The specific gravity of PNC-Ph-EMA monomer showed a tendency to decrease in accordance with the increase in the number of substituents, while conversely, its refractive index increased. The specific gravity of PNC-TF-EMA and PNC-OF-EMA monomers also increased in accordance with an increase in the number of their respective substituent hydrophobic groups, while conversely, the refractive index decreased.
4. The viscosity showed a tendency to increase in the following order : PNC-TF-EMA<PNC-OF-EMA<PNC-Ph-EMA.
