| 摘要 |
<p>Hardener contng. material is encapsulated in microcapsules and admixed to a moulding compsn. (e.g. sand and binder). Capsule walls are destroyed while charging moulding box with moulding compsn. or during or after shaping of mould part, pref. by ultrasonics, electrical alternating field, press. or abrasion. Pref. hardener is encapsulated by adding it to a liquid (A), contact of which with an immiscible liquid (B) leads to a chemical reaction at (A) and (B) interface with formation of a polymer. Hardener-contg. (A) is dispersed in (B). Polymer skin is formed around particles of disperse phase. Polymer-coated particles are filtered and admixed to moulding compsn.</p> |
