Polystyrene (PS) / ˌ p ɒ l i ˈ s t aɪ r iː n / is a synthetic aromatic hydrocarbon polymer made from the monomer styrene. Polystyrene can be solid or foamed. Generalpurpose polystyrene is clear, hard, and rather brittle. It is an inexpensive resin per unit weight.
ألمانيا المصنعين مطحنة الكرة. كرات طحن في الكرة المصنعين مطحنة. Ball mill Wikipedia. A ball mill is a type of grinder used to grind and blend materials for use in mineral dressing, The ball mill is used for grinding materials such as coal, pigments, and feldspar for pottery Grinding can be carried out either wet or dry but the former.