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17 Cards in this Set
- Front
- Back
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Thermoplastic resins are polymers that are generally soluble in _____.
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organic solvents
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A condensation reaction is (fast/slow) and (easy/difficult) to form.
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slow; difficult
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What is the byproduct of a condensation reaction?
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It could be water, ammonia, etc. Some small molecule.
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Which polymerization reaction does not form volatile by-productions?
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addition polymerization
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During addition polymerization, there will always be _____ groups.
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unsaturated
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What are some activators of addition polymerization reactions?
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heat, tertiary amines, light, microwave energy
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What are some inhibitors of polymerization?
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impurities, hydroquinone, and oxygen
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Crosslinking ______ glass transition temperature and strength.
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increases
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Why would you add plasticizers to a polymer?
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to increase solubility and decrease brittleness
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What does the degree of polymerization measure?
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the average number of repeating units
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What does the degree of conversion measure?
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the number of double bonds converted to single bonds during polymerization
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What happens to a polymer at the glass transition temperature?
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It changes from a rigid to a rubbery material.
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Describe a composite resin.
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A combination of materials in which each component retains its identity
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Which type of polymer is impression material?
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a composite resin
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What is butylated hydroxy toluene?
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a composite inhibitor
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What kind of bonds hold together crystalline ceramics?
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Ionic (e.g. NaCl) or covalent (e.g quartz)
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What is an example of an amorphous ceramic?
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silica glass, dental porcelain
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