| 摘要 |
PURPOSE:The title material which is excellent in flame retardancy, broad-band electromagnetic wave absorbing characteristics, can be easily produced and has a high and uniform quality, obtained by foaming a specified hydroxyl group- containing compound mixture, an organic isocyanate and a magnetic powder in the presence of a catalyst. CONSTITUTION:100pts.wt. total of a mixture prepared by mixing a hydroxyl group-containing compound mixture (A) comprising 10-20wt% resol resin oligomer of a hydroxyl equivalent MW (M) of 100-150, 60-40wt% polyoxyalkylenetriol of M of 900-1,100 and 30-40wt% polyoxyalkylenetetraol of M of 130-150 with an organic isocyanate (B) of a MW of 130-140 per isocyanate group, such as liquid diphenylmethane diisocyanate at an NCO/OH of 2-5 and 100-2,000pts.wt. at least one powder (C) of a particle diameter of 0.1-100mu, selected from among magnetic powder such as ferrite and electroconductive powders of carbon, Ni or the like are foamed in the presence of at most 3wt%, based on component A, isocyanate trimerization catalyst (D).
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