Polysulfones (PES / PSU / PPSU)
Polysulfones (PES, PSU, PPSU) are amorphous high-performance thermoplastics valued for hydrolysis resistance, toughness and heat stability in fluid-handling, connectors and under-hood automotive applications.
Overview
The polysulfone family includes polysulfone (PSU), polyethersulfone (PES/PESU) and polyphenylsulfone (PPSU). All are amorphous sulfone polymers with outstanding resistance to hot water and steam, good dielectric properties and toughness that exceeds many other high-heat plastics — particularly PPSU. Automotive uses include under-hood connectors, fuse and relay housings, fluid system components and transparent covers where hydrolysis of polyesters or nylons is a risk. PES offers higher heat and chemical resistance within the family; PSU balances cost and processability; PPSU maximises impact and chemical durability. Injection moulding and extrusion dominate processing. This grouped entry covers the sulfone high-performance polymer class used in automotive and mobility programmes.
Automotive Applications
Similar Materials
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Properties
Category
Type
High-Performance Polymer
Available Colors
Available Forms
Key Properties
- Excellent hydrolysis and steam resistance
- High toughness (especially PPSU)
- Amorphous — good dimensional stability
- Continuous use temperatures typically 150–180°C
- Transparent grades available (PSU/PPSU)
- Higher cost than PA/PC commodity resins
Technical Specifications
Density
~1.24–1.37 g/cm³ depending on grade
Tensile Strength
~70–90 MPa (unfilled family range)
Temperature Resistance
Typical continuous use ~150–180°C (grade-dependent); short peaks higher
Sustainability
Sustainability Rating
Sulfone polymers are specialty resins with limited municipal recycling. Clean moulding scrap can be reprocessed within grade. Long service life in fluid systems reduces replacement waste relative to lesser-resistant plastics.