| 摘要 |
<p>Granular building materials consisting of polymeric (pref. thermoplastic) particles (A) whose surface is extensively covered with another material, (B) such as finely divided sawdust, sand, a silicate, metal powder, or a (semi) continuous rubber film. Used for the dispersion of additives in concrete (e.g. setting accelerator or retarders, fillers, etc) or in bitumen (e.g. materials to improve bond to mineral fillers, flow behaviour or foaming). Accurate weighing and homogeneous dispersion of the additive are simplified, and a standard freer flowing granular material is obtained, regardless of the form of (B) or the temp. Mixing conditions (temp., moisture, etc) are not critical and prolonged hot mixing of bitumen is not required for homogeneous dispersion. Typically scrap PE film is cut into chips, with heating to around 90 degrees C and latex is sprayed in whole mixing. Those cools the chips and covers their surface, with evaporation of part of the water. The product can be stored in sacks.</p> |
