| 摘要 |
An improved composite material is produced by mixing ground gypsum and a plurality of host particles, each having accessible voids therein, together with sufficient liquid to form a dilute slurry; heating the slurry under pressure to a temperature sufficient to calcine the gypsum to calcium sulphate hemihydrate; allowing the calcium sulphate molecules to nucleate and form crystals in-situ in and about the voids in the host particles; dewatering the hot slurry; and drying the dewatered solids to remove substantially all the remaining free water and stabilize the calcium sulphate crystals while still physically interlocked with the host particles. According to a further aspect of the invention, an improved wallboard comprising a plurality of host cellulosic particles each having accessible voids in its body; and calcium sulphate crystals, at least some of which are formed in-situ in and about a significant portion of the accessible voids in the host particles, whereby the host cellulosic particles are physically interlocked with the calcium sulphate crystals. |
