| 摘要 |
1386887 Expanded phenolic resin material H LIEVREMONT and A COMINASSI 21 Aug 1972 [18 July 1972] 38906/72 Headings C3C and C3R An expanded fireproof building material contains 100 p.b.w. of a phenolformaldehyde resin, 15-25 p.b.w. of magnesium silicate powder and 2À2-9 p.b.w. of granulated split mica and optionally finely granulated lead, one or more powdered substances such as magnesium carbonate, titanium dioxide, silica, slate, wood dust or cork dust, mica, and asbestos, and one or more acicular substances such as glass fibres or organic fibres such as polyamide based synthetic fibres. The material may be made by mixing the ingredients at a temperature between 20-80‹ C. and while stirring vigorously adding an acid polycondensation agent such as HCl, H 2 SO 4 , H 3 PO 4 or benzene sulphonic acid and an expansion agent such as NaHCO 3 to the mixture and then extruding the mixture at a temperature below 180‹ C. |
