MODIFICATION REACTIONS OF NOVOLAC RESINS BY EPOXY-CONTAINING POLYPHENYLSILSESQUIOXANES

摘要

The condensation reaction of tetraethoxypolyphenylsilsesquioxane with the excess of epichlorohydrin in the presence of catalysts Fe(III) and Al chloride has been investigated and the corresponding tetraepoxy derivatives has been obtained.The obtained tetraepoxy-derivatives were studied by elemental and functional analyses,determination of the molecular masses,NMR and FTIR spectral data.By polymerisation reaction of tetraepoxypolyphenylsilsesquioxanes with phenol-formaldehyde novolac oligomers epoxy-siliconorganic and phenol-formaldehyde novolac block-copolymers have been obtained.Copolymers at variation of the content of the components in reaction blends with and without accelerators were produced.The change in the amount of epoxy groups in the reaction blends was controlled by FTIR spectra.It was established that with an increase of the length of epoxy-containing polyphenylsilsesquioxane oligomer in the block-copolymer the thermal stability of the produced material rises.On the basis of hardening reactions it was shown that a gel-fraction is formed in spite of the presence of accelerator in the reaction blend.