PP sheet's core value lies in its comprehensive properties of lightness, high toughness, chemical resistance, and ease of processing. It is suitable for applications such as chemical containers, advertising signs, food packaging, and consumer goods. It excels in applications requiring corrosion resistance, lightweight, and low-cost solutions.
Product Performance
Mechanical Properties
High Toughness: Tensile strength 25-40 MPa (10%-20% higher than PE), elongation at break ≥300% (compared to approximately 50%-100% for ordinary plastics), impact strength (cantilever notch) ≥60 kJ/m² (still >30 kJ/m² at -20°C), resistant to repeated bending without cracking (suitable for dynamically loaded components).
Medium Rigidity: Flexural strength 30-50 MPa, elastic modulus 800-1300 MPa (10%-30% higher than HDPE), suitable for medium loads (such as support structures).
Fatigue Resistance: Under cyclic stress of 20 MPa and frequency of 10 Hz, fatigue life >5 × 10⁶ cycles (2-3 times higher than PE), suitable for long-term dynamic load scenarios.
Thermal Properties
Excellent temperature resistance: Long-term operating temperature range -20°C to +100°C (short-term resistance 120°C), melting point approximately 160-170°C (heat deformation temperature 90-110°C under 1.82 MPa load), and maintains a certain degree of toughness even at low temperatures (no brittle cracking at -20°C).
Low thermal conductivity: Thermal conductivity of 0.22-0.24 W/(m·K) (approximately 1/60 of that of metal), making it an excellent thermal insulation material (such as cold storage insulation panels).
Chemical Properties
Excellent chemical resistance: Stable to most acids (such as sulfuric acid and hydrochloric acid), alkalis (such as sodium hydroxide), saline solutions, and organic solvents (such as ethanol and acetone) (no significant swelling at concentrations < 90%). The only insurmountable resistance is strong oxidizing acids (such as concentrated nitric acid and sulfuric acid) and chlorinated hydrocarbons (such as carbon tetrachloride). Environmental Stress Cracking Resistance: Environmental Stress Cracking Resistance (ESCR) > 800 hours (under 0.21 MPa stress), higher than HDPE (> 1000 hours but requiring higher stress), making it suitable for long-term stress load scenarios.
Electrical Properties
Excellent Insulation: Volume resistivity ≥ 10¹⁵Ω·cm, dielectric strength 20-30 kV/mm, dielectric constant 2.2-2.3 (1 kHz), suitable for low-voltage electrical insulation components (such as switch housings and junction boxes).
Processability
Easy to Process: Can be processed through extrusion (sheet thickness tolerance ±0.2 mm), thermoforming (temperature 190-230°C), and stamping (for thin sheets), making it suitable for mass production of complex components. Waste is 100% recyclable (shredded and directly used for extrusion).
Welding Compatibility: Supports hot air welding, ultrasonic welding, and friction welding, with weld strength reaching 70%-80% of the parent material (under standard operation).
Other Characteristics
Self-lubricating: A coefficient of friction of 0.2-0.4 (comparable to HDPE) allows for low-friction operation (e.g., in bearings and guide rails) without the need for lubricants.
Abrasion Resistance: Akron abrasion value ≤ 0.12 cm³/1.61 km (10%-20% higher than HDPE), suitable for low- and medium-speed friction scenarios.
UV Resistance: PP sheets without UV inhibitors are susceptible to aging (surface cracking and reduced strength) when exposed to outdoor conditions. Weather-resistant grades (with the addition of ≥2% carbon black or hindered amine light stabilizers) offer resistance to UV radiation (outdoor service life >8 years).
