Design Guide - Solvay Plastics

Introduction
Udel ® Polysulfone Resins
Udel ® polysulfone resins offer a superior combination of
high-performance properties that include:
• Excellent thermal stability
• High toughness and strength
• Good environmental stress cracking resistance
• High heat deflection temperature, 174°C (345°F)
• Combustion resistance
• Transparency
• Approved for food contact and potable water
• Low creep
This manual has been compiled to provide design
engineers with the necessary information to effectively
use Udel ® polysulfone. It contains the mechanical,
thermal, and chemical properties of these materials
and recommendations for processing and part design.
Chemistry
Chemical Structure — Property Relationships
Udel ® polysulfone is a rigid, strong, high-temperature
amorphous thermoplastic that can be molded, extruded,
or thermoformed into a wide variety of shapes.
Udel ® polysulfone has the following repeating structure
or basic unit:
CH 3
C
CH 3
O
O
S
O
O
N=50-80
This structural unit is composed of phenylene units linked
by three different chemical groups — isopropylidene,
ether, and sulfone — each contributing specific properties
to the polymer. The complex repeating structure imparts
inherent properties to the polymer that conventionally are
gained only by the use of stabilizers or other modifiers.
The most distinctive feature of the backbone chain is the
diphenylene sulfone group:
O
S
O
diphenylene sulfone
The influence of diphenylene sulfone on the properties
of resins has been the subject of intense investigation
since the early 1960’s. The contributions of this group
become evident upon examination of its electronic
characteristics. The sulfur atom (in each group) is in
its highest state of oxidation. Furthermore, the sulfone
group tends to draw electrons from the adjacent
benzene rings, making them electron-deficient. Thermal
stability is also provided by the highly resonant structure
of the diphenylene sulfone group. This high degree
of resonance imparts high strength to the chemical
bonds. Substances stable to oxidation strongly resist
the tendency to lose their electrons to an oxidizer.
It then follows that the entire diphenylene sulfone group
is inherently resistant to oxidation.
Introduction
Udel ® Polysulfone Design Guide
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