The main raw materials for gypsum production are natural gypsum containing calcium sulfate (also known as raw gypsum) or chemical by-products and waste residue containing calcium sulfate. The chemical formula is CaSO. 2h20, also known as dihydrate gypsum. Gypsum is usually prepared from natural dihydrate gypsum. The natural dihydrate gypsum is heated to 107-170 under dry condition. C. Take off part of the water is gypsum (also known as hemihydrate gypsum), this is building gypsum.

目前應(yīng)用較多的是在建筑石膏中摻人各種填料加工制成各種石膏制品（源如紙面石膏板、纖維石膏板警医、石膏空心板亿胸、石膏裝飾板、石膏砌塊酱晾、石膏吊頂?shù)龋┕糜诮ㄖ锏膬?nèi)隔墻、墻面和篷頂?shù)难b飾裝修等赠飞。

At present, it is widely used in building gypsum mixed with various fillers to make various gypsum products (such as paper gypsum board, fiber gypsum board, gypsum hollow board, gypsum decorative board, gypsum block, gypsum ceiling, etc.) for the decoration of internal partition wall, wall and roof of buildings.

石膏板具有長(zhǎng)期徐變的性質(zhì)拼固，在潮濕的環(huán)境中更為嚴(yán)重，且建筑石百膏自身強(qiáng)度較低篙协，又因其呈微酸性今攀，不能配加強(qiáng)鋼筋，故不宜用于承重結(jié)構(gòu)度稻续。為進(jìn)一步改善石膏的耐水性以擴(kuò)大其應(yīng)用范圍妈削，可摻入水泥轿跌、撂喜ぃ化高爐礦渣、石灰汪兢、粉煤灰或有機(jī)防水劑批斯，也可在石膏板表面采用耐水護(hù)面紙或防水高分子材料，采取面層防水保護(hù)等技術(shù)措施掷漱。

Gypsum board has the property of long-term creep, which is more serious in humid environment, and the strength of Shibai plaster is low. Because it is slightly acidic, it can not be reinforced, so it is not suitable for load-bearing structure. In order to further improve the water resistance of gypsum and expand its application scope, cement, granulated blast furnace slag, lime, fly ash or organic waterproof agent can be added, and water-resistant face paper or waterproof polymer material can be used on the surface of gypsum board to take technical measures such as surface waterproof protection.