6'1 Crystallinity of polymers

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6.1 Crystallinity of polymers
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Effect of crystallinity on properties
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What polymers will crystallize?

• Foldable, with flexible chains
• Linear polymers, hence thermoplastics
• Polymers with small side groups.
• Examples of crystalline polymers
• HDPE, PTFE
• Examples of amorphous polymer PS

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6.2 Replacement side groups
Isotactic The replacement groups are all on one
side of the backbone.
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Syndiotactic Replacement side groups
alternating regularly on opposite sides of the
backbone.
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Atactic Replacement groups appear on both sides
of the backbone randomly.
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6.3 Ethenic polymers
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polystyrene Atactic Isotactic Syndiotactic
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6.4 Homo-polymer and co-polymers
Homo-polymer consists of one type of monomer,
e.g. polyethylene (C2H4). Co-polymer consists
of two more more types of mer, like an alloy,
e.g. ABS (AcrylonitrileButadieneStyrene).
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6.5 Subdivision of ceramics
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6.6. Common uses of ceramics
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Common uses of ceramics
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6.7 Basic properties of ceramics
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Compositions of some ceramics
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6.8 Division of materials by cost
Per lb 1997 data Budinski
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Materials costing 1.0-10/lb
1997 data Budinski and Budinski 1999