plasterofParisiksi

Plaster of Paris (POP), known in Finnish as "kipsilevy" or "kipsi," is a widely used building material composed primarily of calcium sulfate hemihydrate. It is derived from natural gypsum mineral, which upon heating to remove water content, transforms into calcium sulfate hemihydrate. When mixed with water, it forms a rapid-setting paste that rehydrates into calcium sulfate dihydrate, creating a hard, durable surface.

Historically, Plaster of Paris has been utilized for creating molds, casts, decorative elements, and architectural features. Its quick setting time and ease of shaping make it popular in sculpture, interior decoration, and medical applications such as orthopedic casts. POP is valued for its smooth finish, affordability, and ease of manipulation.

The manufacturing process involves calcining gypsum at approximately 150°C to produce calcium sulfate hemihydrate. When water is added, it undergoes an exothermic reaction, setting and hardening within minutes. Its physical properties—lightweight, compressible before setting, and capable of attaining fine detail—contribute to its versatility.

Despite its widespread use, Plaster of Paris is sensitive to moisture and can deteriorate over time when exposed to humid environments. It is also brittle, which limits its load-bearing capacity, but enhancements such as reinforcement with fiberglass can improve its strength.

Safety precautions include proper handling to avoid inhalation of dust during mixing, as fine particles can cause respiratory issues. POP should be stored in dry conditions to prevent premature setting or deterioration.

Overall, Plaster of Paris remains a fundamental material in construction, art, and medical fields, valued for its rapid setting characteristics and ease of use, although it requires protection from moisture and physical stress.