Name: _________________________________________________________________ POLYMER NOTES GENERAL PROPERTIES OF POLYMERS 1. Easy to ____________________ 2. Excellent _______________________ can be obtained 3. Produced with close dimensional tolerances 4. Economical 5. Low ____________________properties 6. Poor ____________________resistance 7. Can be produced transparent or in different ____________________ 8. _________________________ to chemicals & corrosion. 9. Thermal and electrical __________________________. 10. Generally _____________________________________ 11. Can be processed in various ways Metals Ceramics/ Glass Polymers Type of Matter Element or mixture Compound or Mixture of compounds Mostly compounds Type of Elements Metallic elements Metals w/ nonmetals OR Semimetals w/ nonmetals Nonmetals Type of Structure Crystalline Ceramics = crystalline Glass = amorphous Mostly amorphous w/ some regions of crystallinity Type of Bonding Metallic bonding Ionic bonding and network covalent bonding Covalent bonding and weak intermolecular forces List some examples these polymers Synthetic polymers=plastics Natural polymers HISTORY OF POLYMERS
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
GENERAL PROPERTIES OF POLYMERS1. Easy to ____________________2. Excellent _______________________ can be obtained 3. Produced with close dimensional tolerances 4. Economical 5. Low ____________________properties6. Poor ____________________resistance 7. Can be produced transparent or in different ____________________8. _________________________ to chemicals & corrosion.9. Thermal and electrical __________________________. 10. Generally _____________________________________11. Can be processed in various ways
Metals Ceramics/Glass
Polymers
Type of Matter Element or mixture Compound orMixture of compounds Mostly compounds
Type of Elements Metallic elements
Metals w/ nonmetalsOR
Semimetals w/ nonmetals
Nonmetals
Type of Structure Crystalline Ceramics = crystalline
Glass = amorphousMostly amorphous w/ some regions of
crystallinity
Type of Bonding Metallic bonding
Ionic bonding and network covalent
bonding
Covalent bonding and weak
intermolecular forces
List some examples these polymersSynthetic polymers=plastics Natural polymers
Developing polymers for tissue repair, replacement and regeneration.Making solar cellsengineering polymers to give specific, desired properties such as biodegradability or biocompatibility
POLYMER DEFINITION
• POLY- “______________” • MERS- “______________”• Polymers are _________________________________ made of
thousands of repeated units called _______________• Monomers are connected with _____________________bonds
• Remember that covalent bonds occur when atoms ___________________ electrons
• This occurs with ________________________-polymers are mostly nonmetals
• Most common nonmetals in polymers • ______________________
• Most important because it makes the backbone of polymer chains
• It can make huge chains because ____________________________________• Other elements can be in polymers__________________, ________________,
Nitrogen, Chlorine, __________________, Silicon
HYDROCARBONSHydrocarbons are classes of chemicals made of carbon and hydrogen.
Name: _________________________________________________________________• Hydrocarbons are classes of chemicals made of
___________ and ________________ • Name is based on how many carbons are in the chain
Polymer Molecular Arrangements
• ALKANES – Hydrocarbons with _________________ bonds between all carbons– Remember: All carbons form 4 bonds– Example: Draw butane – Example: Draw propane
• ALKENES – Hydrocarbons with ___________________ bonds between at least 2 of the carbons
• Double bonds are _____________________ and more _________________ than single bonds• Example: Draw hexene
POLYMERIZATION• Polymerization-
– 2 methods of polymerization• _________________________• _________________________
• Addition Polymerization: – Occurs when monomers are added to one another usually by _____________________________– Initiator:
Amorphous: Molecules arranged in coiled and tangled chains like spaghetti noodles
Examples:
Crystalline: Most of the molecules are arranged in chains stacked folded towels.
Examples:
Name: _________________________________________________________________– What happens to the length of chains as there are more initiators? ____________________
– Example: Draw how polyethylene is made from 2 ethene molecules
• Condensation Polymerization: Method of making a polymer that often _________________________ _________________________________ as a by product
Slime and Crosslinking What about slime keeps it stuck together but still allows it to move and sag? _________________ What was the cross linker in slime? ______________________• Cross linking are __________________________________________________________________
• Crosslinking Properties – Higher tensile strength • More of a solid under high temps• ___________________________________________• More ____________________• More ________________, not ____________________• Resistance to _______________ cracking• Improved behavior at __________________ temps• Slightly better flame resistance
Vulcanization– Process of creating ______________________ in rubber
Name: _________________________________________________________________– If the chains were not linked together rubber would remain _______________ because
individual chains would _______________________________– This cross-linking gives the chains of molecules __________________, ensuring the ball returns
to its ____________________________________.– Changes rubber to ____________, ___________________ material (like in tires, shoe soles, hoses,
and hockey pucks) • Uses _______________________________• Named after Vulcan Roman God of ______________• Often called sulfur curing
Classification of Polymers1. Thermoplastic_______________ when heated and _____________________ when cooled Primary types of used for ________________________Formed/shaped when in _______________________ state. Ex: milk jug, shrink to fit polystyrene2. Thermoset
– _______________________ polymers– _______________________ – set into a solid _______________________– can’t be _______________________ by heat (they simply burn instead) – therefore it is very hard or impossible to _______________________– tends to be _______________________ than a thermoplastic.
– Ex: clothespins, urethane3. Elastomer
– Polymers that show a high degree of _______________________ like rubber– Are _______________________ polymers – Helps make seals, adhesives, molded flexible parts
• Some polymers are _____________ and some polymers are ______________ • Polar molecules are molecules that have __________________________• Polarity affects how they _____________________________________________
• ______________ things dissolve in _______________ liquids – starch peanuts & ______________
Name: _________________________________________________________________• ______________ things dissolve in ______________ liquids
– ______________ & ______________
Polymers in relation to water Hyrdophilic: _______________________________ Hydrophobic: _______________________________
Sodium Polyacrylate Demo (Water Lock)• Why did the sodium polyacrylate absorb so much water?
• When water is added the _________________________ (dissociates) ________________ _______________________________________________
• Can absorb up to __________________ mass in water
• Why did salt reduce how much water it absorbed?• adding more salt ___________________________________________________________
Applications of Sodium polyacrylate (water lock)o _______________________o _______________________o _______________________o _______________________
Sodium Polyacrylate (PolySnow)• How is this sodium polyacrylate (polysnow) different than sodium polyacrylate (Water lock)?
– Water lock: less cross linked, water absorbed __________________________ of polymer chains– Polysnow: more cross linked, water absorbed _____________________ of polymer chains
•
Types of Manufacturing 1. Injection Molding
a. STEPSi) Powder or pelletized polymer heated to liquid state and _________________________ through an
opening called a ____________ii) pressurized material is held in the _____________________________iii) ______ opens and part is removed by _______________ pins
b. ADVANTAGEi) Very precise control of shape and dimensions, _________ processing, _______ waste, _____
automation
Polar and nonpolar don’t mix Polar liquids and polar compounds mix
i) ________________, good for only ______________ parts, needs ________ pressure2. Extrusion
a. STEPSi) Polymer pellets are put in _________________ (barrel with continuous feed screw)ii) Material is ____________________________________iii) Material is ______________ carefully
b. Advantagei) Best suited for parts of _________________________ like pipes and rods, used for wraps, films, or
long continuous partsc. Disadvantage
i) Needs to be ______________________ to keep polymer stable
3. Blow Moldinga. STEPS
i) Softened plastic tube is extrudedii) Tube is clamped at one end and _____________________________________iii) Solid shell
b. Advantagesi) Makes ___________________ parts like bottles, fast cycle, not labor intensive, and relatively cheap
c. Disadvantagesi) Can’t control __________________ well, can’t mold details with __________________, need polymers