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Test your basic knowledge |
Modern Material Science And Engineering 2
Start Test
Study First
Subject
:
engineering
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Kevlar - Twaron - high tensile strength - lightweight - susceptible to uv degradation - nonconductive - bullet- resistant armor - sports equipment - fire resistance
polypphenylene terephyhalamide PPTA
coloring agents
viscose process
stabilizers
2. Molecule containing a highly reactive unpaired electron
free radical
eclipsed conformation/ cis - conformation
quenching
block copolymers
3. Conformation that occurs when the largest substituent in a molecule are offset by 60
random copolymers
extruder
gauche conformation
primary termination
4. Configuration of a substituent in a polymer - in which the substituent is located on the same side of the polymer chain in all repeating units
polymers
isotactic dan
termination
syndiotactic dyad
5. Coloring agents that do not dissolve into the polymer
pigments
mutual termination
most common condensation/step- growth polymerization occur between....
staggered conformation
6. Double bounded organic molecule used to begin addition polymerization
free radical
random copolymers
vinyl monomer
termination
7. Part of the extrusion apparatus that hols a large quantity of polymer pellets as they are fed into the barrel
number average molecular weight Mn
acrylic
quenching
hopper
8. Term used to represent the average molecular weight of a sample containing a wide range of polymer chain lengths. this term is used to avoid confusion between the number average and the weight molecular average weight
secondary bonding
blends
spinneret
relative molecular mass RMM
9. On of the two most common reaction schemes used to create polymers - involving three steps: initiaition - propogation - and termination
addition polymerization/chain growth/free- radical polymerization
gauche conformation
polyamides
end groups
10. Process by which chemical cross - linkages can form between adjacent polymer chains - strengthening the material without significantly damaging its elastic properties
polymethylmethacrylate PMMA
vulcanization
thermoplastics
mutual termination
11. Number of repeat/structural units in a polymer chain
secondary bonding
degree of polymerization DPn
polymethylmethacrylate PMMA
number average molecular weight Mn
12. Two substituents found at both ends of a polymer chain - which have little to no effect on mechanical properties
isotactic dan
blends
polymer backbone
end groups
13. Process used to make thermoset fibers by performing the polymerization reacting in a solbent as the material flows through a spinneret and into a quenching bath
initiation
petroleum
solution spinning
barrel
14. Last step in the polymerization process - which occurs when the free radical of a polymer chain joins the free radical on an end group
elastomers
primary termination
degree of polymerization DPn
polyesters
15. Simple polymeric material produced as pellets in large quantities
High volume thermoplastics HVTP
alternating copolymers
free radical
blends
16. Covalently bonded atoms which are usualy carbon - that comprise the center of the polymer chain.
polymer backbone
plyacrylonitrile PAN
pigments
copolymer
17. Long chain polymers that contain at least 85% of an ester of a substituted aromatic carboxylic acid. these fibers are strong and can dyed or made transpared
most common condensation/step- growth polymerization occur between....
step- growth/condensation polymerization
polyesters
plasticizers
18. Peice of the extrusion apparatus that is used as a filter to separate unmelted particles - dirt - and other solid contaminants from the molten polymer
screen pack
end groups
primary bonding
fillers
19. Primary raw material for most polymers
thermoplastics
cracking
acrylic
petroleum
20. One method of expressing the molecular weight of sample of polymers with averaging based on weight; this method is more useful when large molecules in the sample dominate the behavior
weight average molecular weight Mw
polyurethanes
freeze line
copolymer
21. Polymers that can stretch by 200% or more and still return to their original length when released; polyurethatnes and the aliphatic thermosets(rubbers)
blends
random copolymers
elastomers
petroleum
22. Carbon atom capable of multiple configurations due to four different substituents
alternating copolymers
asymetric
free radical
weight average molecular weight Mw
23. Lightwieght polymer that absorbs water well; the first syntheric polymer ever constructed
viscose process
rayon
staggered conformation
oligomers
24. Formation of a polymer that occurs when two potentially reactive end groups on a polymer react to form a new covalent bond between the polymer chain. this reaction also forms a byproduct - which is typically water
polyurethanes
gauche conformation
stabilizers
step- growth/condensation polymerization
25. Spatial arrangement of substituents around the main chain carbon atom that can be altered only by the breaking of bonds
configuration
trans - conformation
free radical
oligomers
26. Additives that improve a polymer's resistance to variable that cause bonds to rupture - such as heat and light
primary bonding
cracking
stabilizers
isotactic dan
27. Covalently bonded chains of molecules with small monomer units repeated from end to end
side groups/ substituents
polymers
atactic
trans - conformation
28. Additives that cause swelling - which allows the polymer chains to slide past one another more easily - making the polymer softer and more pliable. also used to decrease the viscosity of cement paste to make it easier to flow
homopolymer
constitution
addition polymerization/chain growth/free- radical polymerization
plasticizers
29. Arrangement of the largest substituents where the substituets are offset by 120
polymer backbone
end groups
staggered conformation
polyviyl chloride PVC
30. Stiff and extremely inert polymer - low cost - chemical and moisture resistant - outdoor stability
polyamides
functionality
secondary bonding
polyviyl chloride PVC
31. High distance- dependent bonding between adjacent polymer chains; usually includes hydrogen bonding - dipoles - and van der waals
secondary bonding
blends
most common condensation/step- growth polymerization occur between....
pigments
32. Configuration of a polymer in which the sucstituent is located on opposite sides of the molecule in each repeating unit
additives
syndiotactic dyad
polypphenylene terephyhalamide PPTA
polyesters
33. Plexiglas - lucite - transparent - shatterproof - biocompatible - hockey rinks - taillights - implants
polymethylmethacrylate PMMA
poly- p- phenylene benzobisoxazole PBO
addition polymerization/chain growth/free- radical polymerization
propagation
34. Two or more polymers mechanically mixed together but without covalent bonding between them
weight average molecular weight Mw
condensation/step- growth polymerization
coloring agents
blends
35. First step in the process of polymerization - during which a free radical is formed
initiation
melt spinning
most common condensation/step- growth polymerization occur between....
quenching
36. Polymer made up of two of more differenet monomers covalently bonded together
dyes
secondary bonding
copolymer
configuration
37. Type of plymer processing similar to extrusion but can be used to develop parts with complex shapes rapidly
alternating copolymers
fillers
configuration
injection molding
38. Orlon - acrilan - lightweight - durable - carbon - fiber precursor - tennis - racing bikes - helmets
propagation
block copolymers
plyacrylonitrile PAN
shot size
39. Formation of side chains along the backbone; presence of branches disrupts the interactions beween adjacent chains; lowering the tensile strength - melting point - stiffness - crystallinity - and density
polyviyl chloride PVC
branching
plasticizers
plyacrylonitrile PAN
40. Polymers comprised of two or more different monomers that attach to the chain in long runs of one type of monomer - followed by another monomer AAAAAAAAAAAAABBBBBBBBBBBBBBBBBBAAAAAAAA
block copolymers
addition polymerization/chain growth/free- radical polymerization
polymer backbone
functional groups
41. Term associate with blown - film apparatus - which indicated the point at which the molecules develop a more crystalline orientation around the bubble of air
freeze line
oligomers
configuration
weight average molecular weight Mw
42. Polymers that cannot be repeatedly melted and re- formed due to strong covalent bonding between chains
number average molecular weight Mn
constitution
thermosets
oligomers
43. Covalent bonding of the polymer backbone and side groups
primary bonding
thermosets
condensation/step- growth polymerization
poly- p- phenylene benzobisoxazole PBO
44. Circular - stationary block with small holes through which molten polymer can flow to take the shape of a fiber
extruder
spinneret
tow
shot size
45. Small chains of bonded monomers whose properties would be altered by the addition of one more monomer unit
viscose process
oligomers
plasticizers
fillers
46. An acid and an alcohol
shot size
number average molecular weight Mn
thermosets
most common condensation/step- growth polymerization occur between....
47. Smallest repeating unit in a polymer. aka repeat unit
condensation/step- growth polymerization
polyamides
cracking
structural unit
48. Is not asymetric and cannot have multiple configurations
degree of polymerization DPn
tow
propagation
any carbon with double bonds or repeated substituents
49. Refers to the spatial geometry of the main chain carbon and substituents that can be changed by rotation and flexural motion
conformation
trans - conformation
functionality
tow
50. Polymers comprised of two or more different monomer units that attach to the chain in an alternating pattern A-B-A-B...
solution spinning
elastomers
alternating copolymers
number average molecular weight Mn
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