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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. Second- order thermodynamic transition in which the onset of large scale chain mobility occures in polymers. Bellow Tg the polymer is glasslike and brittle. above Tg the polymer becomes rubbery and flexible
constitution
plyacrylonitrile PAN
glass transition temperature Tg
structural unit
2. Technique used to make rayon - which involves treating cellulose from wood or cotton with alkali and extruding it through a spinneret
thermosets
termination
viscose process
blends
3. Spatial arrangement of substituents around the main chain carbon atom that can be altered only by the breaking of bonds
configuration
number average molecular weight Mn
plyacrylonitrile PAN
primary bonding
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
branching
block copolymers
isotactic dan
relative molecular mass RMM
5. Stiff and extremely inert polymer - low cost - chemical and moisture resistant - outdoor stability
branching
polyviyl chloride PVC
melt spinning
alternating copolymers
6. 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
conformation
polyesters
secondary bonding
blends
7. High distance- dependent bonding between adjacent polymer chains; usually includes hydrogen bonding - dipoles - and van der waals
freeze line
vulcanization
condensation/step- growth polymerization
secondary bonding
8. Peice of the extrusion apparatus that is used as a filter to separate unmelted particles - dirt - and other solid contaminants from the molten polymer
block copolymers
screen pack
functional groups
degree of polymerization DPn
9. Second stage of polymerization process during which the polymer chain begins to go as monomers are added to the chain
random copolymers
polyviyl chloride PVC
oligomers
propagation
10. Polymers that can stretch by 200% or more and still return to their original length when released; polyurethatnes and the aliphatic thermosets(rubbers)
barrel
injection molding
isotactic dan
elastomers
11. Part of the polymer processing apparatus through which the polymer is pushed - causing the polymer to form a simple shape - such as a rod or tube
die
gauche conformation
condensation/step- growth polymerization
relative molecular mass RMM
12. Last step in the polymerization process - which occurs when the free radical of a polymer chain joins the free radical on an end group
barrel
dyes
hopper
primary termination
13. Polymers comprised of two or more different monomer units that attach to the chain in an alternating pattern A-B-A-B...
alternating copolymers
vulcanization
coloring agents
vinyl monomer
14. Terminating a condensation/step- growth polymerization reaction by adding a material with only one functional group
quenching
step- growth/condensation polymerization
aramid
barrel
15. Small chains of bonded monomers whose properties would be altered by the addition of one more monomer unit
oligomers
free radical
solution spinning
graft copolymers
16. Lightwieght polymer that absorbs water well; the first syntheric polymer ever constructed
atactic
constitution
die
rayon
17. Atoms attached to the polymer backbone.
functional groups
end groups
side groups/ substituents
rayon
18. Covalently bonded chains of molecules with small monomer units repeated from end to end
aramid
end groups
fillers
polymers
19. Term used to describe a polymer that contains significant numbers of both syndiotactic and isotactic dyads
atactic
High volume thermoplastics HVTP
extruder
initiation
20. Conformation that occurs when the largest substituent in a molecule are offset by 60
aramid
gauche conformation
most common condensation/step- growth polymerization occur between....
barrel
21. Softening agents
mutual termination
tow
plasticizers
branching
22. Specific arrangements of atoms that cause organic compounds to behave in predictable ways
functional groups
atactic
cracking
blends
23. Polymers comprised of two or more different monomers - which attach to the polymer chain in no particular order of pattern
functionality
initiation
vulcanization
random copolymers
24. Covalent bonding of the polymer backbone and side groups
extruder
alternating copolymers
aramid
primary bonding
25. Additives that improve a polymer's resistance to variable that cause bonds to rupture - such as heat and light
stabilizers
block copolymers
plyacrylonitrile PAN
propagation
26. Primary raw material for most polymers
initiation
constitution
petroleum
oligomers
27. Number of repeat/structural units in a polymer chain
weight average molecular weight Mw
degree of polymerization DPn
freeze line
nylon
28. Low- molecular- weight building blocks repeated in the polymer chain
monomers
any carbon with double bonds or repeated substituents
barrel
relative molecular mass RMM
29. Polymer that is made up a single repeat unit
homopolymer
trans - conformation
screen pack
polymer backbone
30. Two or more polymers mechanically mixed together but without covalent bonding between them
alternating copolymers
blends
most common condensation/step- growth polymerization occur between....
plasticizers
31. Number of bonds a molecule has formed
functionality
polymers
freeze line
asymetric
32. Kevlar - Twaron - high tensile strength - lightweight - susceptible to uv degradation - nonconductive - bullet- resistant armor - sports equipment - fire resistance
addition polymerization/chain growth/free- radical polymerization
polypphenylene terephyhalamide PPTA
primary bonding
oligomers
33. 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
pigments
elastomers
weight average molecular weight Mw
end groups
34. Orlon - acrilan - lightweight - durable - carbon - fiber precursor - tennis - racing bikes - helmets
polyviyl chloride PVC
elastomers
acrylic
plyacrylonitrile PAN
35. Form of the molecular weight of a sample of polymer chains determined by dividing the mass of the specimen by total number of mols present; always less than weight average molecular weight; all molecules regardless of size correlate well with Mn
number average molecular weight Mn
branching
conformation
barrel
36. Process by which chemical cross - linkages can form between adjacent polymer chains - strengthening the material without significantly damaging its elastic properties
end groups
any carbon with double bonds or repeated substituents
vinyl monomer
vulcanization
37. 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
gauche conformation
polymers
plasticizers
vinyl monomer
38. Configuration of a polymer in which the sucstituent is located on opposite sides of the molecule in each repeating unit
condensation/step- growth polymerization
syndiotactic dyad
polyamides
polyviyl chloride PVC
39. Covalently bonded atoms which are usualy carbon - that comprise the center of the polymer chain.
alternating copolymers
polymer backbone
polyurethanes
poly- p- phenylene benzobisoxazole PBO
40. Polymers in which one chain of a particular monomer is attached as a side to a chain of another chain of monomer
mutual termination
random copolymers
most common condensation/step- growth polymerization occur between....
graft copolymers
41. Circular - stationary block with small holes through which molten polymer can flow to take the shape of a fiber
spinneret
polymers
screen pack
weight average molecular weight Mw
42. First step in the process of polymerization - during which a free radical is formed
initiation
pigments
homopolymer
eclipsed conformation/ cis - conformation
43. Molecule containing a highly reactive unpaired electron
injection molding
free radical
hopper
propagation
44. Sylon - transparent - shatter proof - biocompatible - hockey rinks - taillights - implants
screen pack
functionality
tow
poly- p- phenylene benzobisoxazole PBO
45. One type of polymer that contains at least 85% of polyacrylonitrile PAN
thermoplastics
any carbon with double bonds or repeated substituents
poly- p- phenylene benzobisoxazole PBO
acrylic
46. Arrangement of the largest substituents where the substituets are offset by 120
cracking
staggered conformation
primary termination
isotactic dan
47. Pigments or dyes that change the way light is absorbed or reflected by a polymer
monomers
plyacrylonitrile PAN
coloring agents
mutual termination
48. Relative configuration of adjecent asymmetric carbons
tacticity
polyamides
addition polymerization/chain growth/free- radical polymerization
structural unit
49. Process of pushing polymers through a spinneret and winding the solidified fibers onto a tow - which imposes a shear stress on the fibers upstream as they emerge from the spinneret
number average molecular weight Mn
relative molecular mass RMM
stabilizers
melt spinning
50. Two substituents found at both ends of a polymer chain - which have little to no effect on mechanical properties
oligomers
atactic
end groups
polyviyl chloride PVC