| 摘要 |
<p>A non-flammable insulating sandwich material, consists of a central layer and two external layers. The central layer, of density 70-300 g/l, contains 99-60% of light mineral particles of mean dia. 0.05-3 (0.2-2)mm and apparent density 30-150. (40-100) g/l; 0-40% of mineral additive either fibrous or particulate (dia. 1-100 mum), the particles being agglomerated addn. of 1-30% (2-10%) of an organic binder of high mol. wt., heat-resistant and having a service temp. (DIN 53446) >100 degrees C. The external layers, of density 600-2000 g/l contain 96-60% inert mineral filler, insol. in water, in form of fine particles of size 1-200 (1-50)m and apparent density >1 g/cm3; 2-30% of mineral or organic fibres of length 2-50 mm; and 2-30% of the organic binder. The sandwich material has thickness of 10-100 (10-60)mm; the exterior layers are 0.5-5 (0.5-2) mm thick. The sandwich materials are used in the building industry, where their non-flammability, good mechanical properties, esp. high resistance to compression and to bending, and good abrasion resistance are valuable. The method overcomes the disadvantages of earlier methods which did not readily yield materials that combined flame-resistant props. with good mechanical props.</p> |
