CHE 333 Class 22

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CHE 333 Class 22

• Polymers Continued

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Molecular Configuration
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Stereoisomerism
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Geometrical Isomerism
Need double bond between carbons in this case.
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Stress Strain Behavior
Polymers are both strain rate dependent and
temperature dependent in their Stress strain
behavior. Higher temperatures and slower strain
rate more plasticity
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Visco-elasticity (Temperature Effect)
Elastic
Load History
Viscous
Visco-elastic
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Polymer Relaxation
A Crystalline isotactic polystyrene B lightly
crosslinked atactic polystyrene C- Amorphous
polystyrene.
Stress required to maintain a fixed strain at a
constant temperature
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Glass Transition in Polymers
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Polymer Deformation
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Vulcanization
Used to control the properties of rubber- more
crosslinking stiffer and stronger.
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Forming
Extrusion also soft metals
Compression Molding
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Forming
Transfer molding
Injection molding
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Forming
Thermo vacuum forming
Reaction Injection Molding
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Forming
Blow molding
Reverse roll coating
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Forming
Calendering
Spinning
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Forming
Thermo vacuum forming
Reaction Injection Molding
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Fuel Cells
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