| 摘要 |
<p>Strengthening of glass fibres with polyfunctional cyanic acid esters. N2A. (I) applied in monomeric or precondensed form (e.g. B-stage precondensate prepd. by thermal treatment at 70-180 degrees C. for 2-50 hrs. opt. with a catalyst) in solvents such as acetone, methyl ethyl ketone, chlorobenzene, ethyl acetate, acetophenone or chloroform, followed by thermal treatment at 150-200 degrees C. to cure (I) to high mol. wt. triazines. (I) have the formula:- R(O-CN)n (where R = aromatic gp. and n = 2-6). Examples are m- or p-phenylene bis cyanate, dicyanatonaphthalenes, dicyanatodiphenylsulphone, cyanic acid esters as described in DT. 1,251,023 and esp. 4,4'-dicyanatodiphenylmethylmethane (II). Uses are particularly for strengthening glass fibres to be used as reinforcement in plastics materials.</p> |
