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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. 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
most common condensation/step- growth polymerization occur between....
oligomers
spinneret
weight average molecular weight Mw
2. Formation of a plymer that occurs when two potentially reactive end groups on a polymer react to form a new covalent bond between the polymer chains. this reaction also forms a biproduct - usually water
condensation/step- growth polymerization
relative molecular mass RMM
plyacrylonitrile PAN
atactic
3. Stiff and extremely inert polymer - low cost - chemical and moisture resistant - outdoor stability
poly- p- phenylene benzobisoxazole PBO
nylon
polyviyl chloride PVC
coloring agents
4. Coloring agent that is dissolved directly into the polymer - causing the polymer to change color
dyes
side groups/ substituents
syndiotactic dyad
plasticizers
5. Occurs when substituent are directly aligned - causing substantial repulsion between the substituents and an unfavorable conformation.
eclipsed conformation/ cis - conformation
glass transition temperature Tg
tow
copolymer
6. Molecules added to a polymer to enhance or alter specific properties or molecules added to concrete for purposed other than altering a specific property
syndiotactic dyad
additives
polyurethanes
polymers
7. 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
polymer backbone
blends
melt spinning
pigments
8. Double bounded organic molecule used to begin addition polymerization
pigments
addition polymerization/chain growth/free- radical polymerization
nylon
vinyl monomer
9. High distance- dependent bonding between adjacent polymer chains; usually includes hydrogen bonding - dipoles - and van der waals
secondary bonding
additives
degree of polymerization DPn
eclipsed conformation/ cis - conformation
10. An acid and an alcohol
most common condensation/step- growth polymerization occur between....
primary termination
configuration
end groups
11. 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
viscose process
number average molecular weight Mn
polyesters
branching
12. Number of bonds a molecule has formed
primary bonding
step- growth/condensation polymerization
functionality
alternating copolymers
13. Specific arrangements of atoms that cause organic compounds to behave in predictable ways
functional groups
plyacrylonitrile PAN
injection molding
step- growth/condensation polymerization
14. Two substituents found at both ends of a polymer chain - which have little to no effect on mechanical properties
random copolymers
polypphenylene terephyhalamide PPTA
High volume thermoplastics HVTP
end groups
15. 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
polyviyl chloride PVC
isotactic dan
barrel
atactic
16. 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
structural unit
polyesters
polymethylmethacrylate PMMA
melt spinning
17. Softening agents
quenching
vinyl monomer
any carbon with double bonds or repeated substituents
plasticizers
18. Configuration of a polymer in which the sucstituent is located on opposite sides of the molecule in each repeating unit
aramid
fillers
syndiotactic dyad
oligomers
19. Conformation in which the largest substituents are offset by 180
trans - conformation
relative molecular mass RMM
pigments
functional groups
20. Additives that improve a polymer's resistance to variable that cause bonds to rupture - such as heat and light
stabilizers
pigments
quenching
polypphenylene terephyhalamide PPTA
21. Atoms attached to the polymer backbone.
aramid
coloring agents
alternating copolymers
side groups/ substituents
22. Polymers in which one chain of a particular monomer is attached as a side to a chain of another chain of monomer
polyurethanes
most common condensation/step- growth polymerization occur between....
graft copolymers
stabilizers
23. Polymer that is made up a single repeat unit
polyesters
fillers
homopolymer
functional groups
24. Second stage of polymerization process during which the polymer chain begins to go as monomers are added to the chain
functionality
propagation
block copolymers
configuration
25. Plexiglas - lucite - transparent - shatterproof - biocompatible - hockey rinks - taillights - implants
mutual termination
aramid
polymethylmethacrylate PMMA
primary termination
26. Molecule containing a highly reactive unpaired electron
plyacrylonitrile PAN
initiation
primary bonding
free radical
27. Covalent bonding of the polymer backbone and side groups
polymer backbone
extruder
degree of polymerization DPn
primary bonding
28. Type of plymer processing similar to extrusion but can be used to develop parts with complex shapes rapidly
polypphenylene terephyhalamide PPTA
eclipsed conformation/ cis - conformation
injection molding
nylon
29. Kevlar - Twaron - high tensile strength - lightweight - susceptible to uv degradation - nonconductive - bullet- resistant armor - sports equipment - fire resistance
elastomers
polypphenylene terephyhalamide PPTA
primary termination
addition polymerization/chain growth/free- radical polymerization
30. Porcess of breaking large organic hydrocarbons into smaller molecules
nylon
cracking
mutual termination
die
31. 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
tow
glass transition temperature Tg
stabilizers
gauche conformation
32. Small chains of bonded monomers whose properties would be altered by the addition of one more monomer unit
initiation
oligomers
quenching
poly- p- phenylene benzobisoxazole PBO
33. Covalently bonded chains of molecules with small monomer units repeated from end to end
blends
polymers
polyviyl chloride PVC
screen pack
34. Polymer made up of two of more differenet monomers covalently bonded together
polyamides
coloring agents
secondary bonding
copolymer
35. Polymers that cannot be repeatedly melted and re- formed due to strong covalent bonding between chains
thermosets
primary bonding
structural unit
glass transition temperature Tg
36. Specified weight of a polymer that is injected into the mold at the end of the barrel during the injection molding process
stabilizers
shot size
number average molecular weight Mn
screen pack
37. First step in the process of polymerization - during which a free radical is formed
screen pack
most common condensation/step- growth polymerization occur between....
initiation
tow
38. Term associate with blown - film apparatus - which indicated the point at which the molecules develop a more crystalline orientation around the bubble of air
plasticizers
die
freeze line
constitution
39. Device used in the processing of polymers that melts polymer pellets and feeds them continuously through a shaping device
mutual termination
thermosets
extruder
vulcanization
40. One of the two different types of termination in the polymerization process. during this type of termination - the free radicals from two different polymer chains join to end the propogation process
stabilizers
copolymer
mutual termination
relative molecular mass RMM
41. Polymers that contain amide (- N-) groups in the chain
glass transition temperature Tg
polyamides
polymethylmethacrylate PMMA
nylon
42. Sylon - transparent - shatter proof - biocompatible - hockey rinks - taillights - implants
termination
poly- p- phenylene benzobisoxazole PBO
extruder
staggered conformation
43. Large spool that is used to wind solidified polymer fibers after they have been pushed through the spinneret
step- growth/condensation polymerization
functional groups
tow
weight average molecular weight Mw
44. Polymers with low melting poins due to the lack of covalent bonding between adjacent chains. such polymers can be repeatedly melted and re- formed
graft copolymers
degree of polymerization DPn
thermoplastics
viscose process
45. Final step in the polymerization process - which causes the elongation of the polymer chain to come to an end
termination
initiation
vinyl monomer
melt spinning
46. Term used to describe a polymer that contains significant numbers of both syndiotactic and isotactic dyads
tacticity
relative molecular mass RMM
plasticizers
atactic
47. Last step in the polymerization process - which occurs when the free radical of a polymer chain joins the free radical on an end group
nylon
primary termination
free radical
eclipsed conformation/ cis - conformation
48. Refers to the spatial geometry of the main chain carbon and substituents that can be changed by rotation and flexural motion
additives
conformation
functionality
side groups/ substituents
49. Part of the extrusion apparatus that hols a large quantity of polymer pellets as they are fed into the barrel
weight average molecular weight Mw
configuration
polyurethanes
hopper
50. On of the two most common reaction schemes used to create polymers - involving three steps: initiaition - propogation - and termination
secondary bonding
additives
number average molecular weight Mn
addition polymerization/chain growth/free- radical polymerization