Plastic Materials Properties

Overview

Engineering reference data for Plastic Materials Properties in material science and properties.

Key Formulas

Stress

$\sigma = \frac{F}{A}$

Force per unit area.

Strain

$\varepsilon = \frac{\Delta L}{L_0}$

Change in length per original length.

Hooke's Law

$\sigma = E \varepsilon$

Stress proportional to strain in elastic region.

Thermal Expansion

$\Delta L = \alpha L_0 \Delta T$

Length change due to temperature.

Variables

Common Plastic Materials in Valve Applications

Based on the introduction to plastic materials used in valves, common engineering plastics and their general properties include:

• PVC (Polyvinyl Chloride): Good chemical resistance, cost-effective, suitable for lower temperature and pressure applications.
• PP (Polypropylene): Excellent chemical resistance, higher temperature capability than PVC, good fatigue resistance.
• PVDF (Polyvinylidene Fluoride): High purity, excellent chemical resistance, good mechanical strength, and higher temperature tolerance.
• PTFE (Polytetrafluoroethylene): Outstanding chemical resistance, very low friction, wide temperature range, but more flexible.
• CPVC (Chlorinated Polyvinyl Chloride): Similar to PVC but with higher temperature and pressure ratings due to chlorination.
• PEEK (Polyether Ether Ketone): High-performance engineering plastic with exceptional mechanical strength, chemical resistance, and thermal stability for severe service.

The selection depends on the specific service conditions including chemical compatibility, operating temperature, pressure, and mechanical requirements.

References

• Original Source