Download Physical Science Chapter 8

(8th) Chapter 8-3 Cornell Notes
• “Polymers and
Composites”
(8th) Chapter 8-3 Cornell Notes
• Key Questions
How do polymers form?
What are composites made of?
How can you reduce the amount of plastic waste?
(8th) Chapter 8-3 Cornell Notes
Key Terms
proteinamino acidplasticcomposite-
(8th) Chapter 8-3 Cornell Notes
Paragraph 1
polymer:
large, complex molecule made of smaller
molecules;
carbon common atom;
common because can have 4 bonds and
structures like rings, etc.
(8th) Chapter 8-3 Cornell Notes
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monomers: smaller
molecules that make
up polymers in long,
repeating pattern
chains.
(8th) Chapter 8-3 Cornell Notes
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polymers either natural or synthetic;
natural polymers:
1. cellulose gives strength to plant cells
and indigestible to us;
2. starches form from sugar molecules,
digestible;
3. proteins made from amino acid
combinations, digestible (forms
fingernails, carries O2 in blood).
(8th) Chapter 8-3 Cornell Notes
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synthetic polymers:
many made in factories from simple
materials like coal, oil;
includes carpets, clothing, glue;
plastics can be molded or shaped are
the most common.
(8th) Chapter 8-3 Cornell Notes
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composites:
combine 2 or more into new material with different
properties;
can be better than either material alone;
many composites include one or more polymers;
natural composite: wood;
synthetic composite: fiberglass.
(8th) Chapter 8-3 Cornell Notes
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synthetic polymers:
inexpensive to make;
strong;
last a long time;
problem with disposal, creates
major trash problem;
possible solution: recycling.