| 摘要 |
<p>New thermoplastic resin compsn. contains, as filler, particulate amorphous silica. The particulate amorphous silica is obtd. either by vapour phase oxidn. of silicon or by the sublimation and subsequent condensation of silica or is a mixt. of these silicas. A pref. particulate amorphous silica is obtd. as a by-prod. in the prodn. of silicon metal or ferrosilicon in a reduction furnace. The pref. amorphous silica contains >=8 wt. % SiO2, has a real density of 2.20-2.25 g/cm2 and has a specific surface area of 18-22 m2/g. The pref. particles are substantially spherically and at least 60 wt. % of the particles are less than 1 micron. Used in pipes and conduits, guttering, footwear soles, etc. The filler gives a compsn. having high impact strength and low brittleness. It can be used at higher loadings than known fillers to give a lower cost product, without impairing properties such as chemical resistance and water absorption. The filler can assist processability and can give improved surface finish and fire resistance.</p> |
