MODIFICATION OF PHENOL-FORMALDEHYDE NOVOLAC WITH 1,7-BIS(CARBOXYMETHYLCARBAMOYL)-M-CARBORANE AND ZINC OLIGOSALT

摘要

It is known that composites produced in a novolac melt with 10 wt.% additions of zinc oligosalt of m-carboranedicarboxylic acid (Zn-MC) have increased thermal stability and retention of strength characteristics. However, the infusibility and rigid structure of oligosalt Zn-MC makes the production of homogeneous composite materials significantly more difficult, it is stated. It was assumed that the introduction into this oligosalt of methylene fragments would make it more flexible and thereby improve its compatibility with different polymers and increase the strength characteristics of the composites. To test this assumption, 1,7-bis(carboxymethylcarbamoyl)-m-carborane (GK) and its zinc oligosalt (Zn-GK) were synthesised. Novolac composites were obtained with a content of 10 wt.% Zn-GK and GK respectively, and for comparison, novolac composites with 10 wt.% additions of Zn-m-carboranecarboxylic acid (MK) dichloride and MK, in which there were no CH2 or amide fragments. From the results presented in the research, it was concluded that the presence of -CH2 and Zn-GK used for the modification of novolac, raises the heat resistance of the latter through the formation of a crosslinked structure that is heat stable even at 900 degrees C and which retains up to 50% of the initial strength of the specimens. 5 refs. (Article translated from Plasticheskie Massy, No.12, 2004, p.35-6).