PHYSICS POLYMER Fall 2009-Edge
EMA 6165 - EXAM 2
STUDENT UFID#:______________________
(use the NEW UF ID No.)
INSTRUCTIONS: Read the entire exam carefully. Answer every question to the best of your ability, based
upon the available information. State all assumptions you use in answers.
SECTION I: Polymer Structures/Properties.
State the polymerization mechanism, i.e., condensation, addition, ring opening.
State the relative Tg and/or Tm for each polymer. (20pts)
Polymer
1. poly(propylene)
2. poly(arylene ether
imide)
3. poly(hexamethylene
adipamide)
4. poly(butadiene)
5. poly(ethylene)
6. poly(bisphenol A
carbonate) Lexan
Polymerization
Mechanism (2pt)
Tg (1pt)
Tm (1pt)
POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
Concepts. Answer the following statements with TRUE or FALSE. If the statement is
false, state the reason(s). If you believe a statement can be made TRUE by a simple
qualifier, then state it clearly. (Normally only a single word change is required.) (12 pts)
7.
Spinodal decomposition represents nucleation and growth kinetics of phase segregation.
8.
The osmotic pressure of the dissolved polymer chain scales inversely with the hydrodynamic
volume of the chain.
9.
The chi parameter is temperature independent.
10. The second virial coefficient equals zero at a chi value of 3/2.
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POLYMER PHYSICS - Fall 2009-Edge
II.
EMA 6165 - EXAM 2
Graphical Relationships:
1. Each plot should be represented as a linear function if possible through algebraic
manipulation.
2. You must provide all equations used to create the plot
3. Label all axes appropriately, i.e., provide units and orders of magnitude.
4. STATE ALL ASSUMPTIONS required.
11. 5Chi parameter versus chain concentration (state assumptions clearly)
(6pts)
12. Given a perfectly elastic chain, plot the ultimate stress as a function of the root (6pts)
mean square end to end distance. Show all equations!
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POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
SECTION II: Definitions/Concepts:
Give a BRIEF description for each of the following terms in the SPACE provided. 16 pts,
Use equations or words or figures.
13. Extension Ratio:
14. <Me>:
15. LCST:
16. Isothermal compressibility:
17. SEBS:
18. Characteristic ratio:
19. Creep:
20. Combinatorial Entropy :
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POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
SECTION III: Engineering Problem
21.
You are given and semi-interpenetrating network, i.e. a second polymeric network is 15
formed within an existing network. You have to determine if one or both networks are pts
elastomers. Describe the experiments that you would perform and the information
you would need to answer the question. REMINDER: You must define the polymers
and their differences to answer this question.
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POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
HONOR CODE: We, the members of the University of Florida community, pledge to hold ourselves and our peers
to the highest standards of honesty and integrity.
Signature:___________________________________________________________
The take home portion of the exam has been emailed
directly to you. Contact me if you have any questions.
The equation sheet on the course site can be used as a
reference.
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POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
SECTION III: TAKE HOME DUE by EMAIL to [e-mail]
by 7 PM on Sunday, November 2, 2009.
State CLEARLY any and all assumptions applied developing the solution.
22.
Review the following citation:
25 pts
Morphology and mechanical properties of polyolefinic thermoplastic
elastomer I. Characterization of deformation process, Takuo Asamia and Kohhei Nittab, Polymer 45 (2004) 53015306
http://brennan.mse.ufl.edu/Courses/ema6165/References/PP_EPDM_Elasticity
_2004.pdf.
Estimate the apparent weight molecular between cross links for the EPDM
presented in Figure 3 (p5304). Use the first two labeled data points at
approximately 7 and 11 MPa (note the figure is labeled incorrectly). Assume a
linear response in strain between these two values. Show all calculations.
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POLYMER PHYSICS Fall 2009-Edge
EMA 6165 - EXAM 2
Rubber Elasticity:
Thermodynamics of Mixing
NV kT 2
2
RT
2 MC
1
2
MC Mo
RT
MC
1
3
0 x
0x
RT
Mc
1/ 3
E 1 / 2 E 1 / 2
H m Vm 1 2 1 2
V
V1
2
H m N1 2 1, 2 k T
1
2
G mix RT ln 1 2 1 2 1 2
x
2
0 N v kT x x 3y 2
x
STUDENT UFID#:______________________
(use the NEW UF ID No.)
1
x 2
x
RT
1
x 2
Mc
x
1, 2 B1
V1
1 2 2
RT
1
C
C
21 2 C
2
1
1
2
2
1
1
X 2 C
2G
1
1
1 2
22
1 2 C X
2
f * 2
NV RT 2
*
f
f * 2
r2
N v RT i 2 2
r0
f*
x (t )
E
S
f
l T l
T ,V
T ,V
2
C
1
c 1
2
T
E
f
f
T
l
T
T ,V
Crystallization & Kinetics
P
l ,V
4d0 N v kT
1
* 7
3
R0
Nc k
[
2
( x 2 y 2 z 2 3 ) (ln( x y z )) ]
S
RT
1
2
ln1 2 1 x 2 12
V1
t
a
1 1 R Vu
o H
1
T
T
V
f
f
f
1
T
f
h
Tmo
Energy
f
v 2b l 2v f ab e
POLYMER PHYSICS - Fall 2009-Edge
EMA 6165 - EXAM 2
GI boaonsi
Q
G Go expQ * RT *exp K * RT
I
D
gI
G b S g aN
I
T
0.5
1 2g
SK
Nk i
Gn
C Tm
kTC TC TC
0.5
n 1
m1 mo 1
mo s
1 V
V T P ,l
P
Tm
T
n 1
t 1 exp kt n
Physical Aging Behavior/Viscoelasticity
1 V
V P l ,T
Chain Dimensions/Molecular Weight
Mn
N M
N
i
i
i
2
Kc
1
1 16 2 r
sin2 2 A2 c
2
R M W M W 3
2
6
f o T To
ln At
f o f T To
n
p(r , n) 2 l 2
3
B f o T To
ln1 (t1 , T1 )
ln 2 (t 2 , T2 ) f o f T To
n
p( x , y , z, n) 2 l 2
3
B
8.86 T To
ln1 (t1 , T1 )
ln 2 (t 2 , T2 ) 101.6 T To
ln1 (t1 ,T1 ) 17.4 T To
ln 2 (t 2 , T2 ) 51.6 T To
Ae
Vo
B
V
f
f f o T To
f
General Thermodynamics
2
g
r
3
3
2
4 r 2 e
2
e
3 r 2
2 nl 2
3 x 2 y 2 z 2
2 nl 2
dr
dxdydz
ro2
nl 2
6
6
r 2 nl 2
1 cos(180 )
1 cos(180 )
1 cos 180 1 cos
r 2 nl 2
1 cos 180 1 cos
a
KM V
2.5 4
3
2
Reo
M
3
2
M
1
2
3
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POLYMER PHYSICS - Fall 2009-Edge
r2
M
3
2
M
1
2
EMA 6165 - EXAM 2
ln1 (t1 ,T1 ) 17.4 T To
ln 2 (t 2 , T2 ) 51.6 T To
3
o
Ae
Vo
B
V
f
f f o T To
f
De =
2Cm 1 1 M 2
T
= n
t o e i
G
t o
1
5
=
3
K
M
*
P R4
Gf
8LQ
1 2.5 14.1 2
= A eE / RT
Go
= A eV/V
(t ) o cos t
0
11Tg1 22Tg 2 p 1 1 2 Tgp
Tg
11 22 p 1 1 2
w 0.5 max min
Fluid Dynamics (Rheology)
Viscoelasticity and Mechanics
EYoung's 2 GShear 1 3 B 1 2
B
R 4 P
Q
8 L
f o T To
ln At
f o f T To
Wh2 h P
=
*
Q
2 s 2 2m L
B f o T To
ln1 (t1 , T1 )
ln 2 (t 2 , T2 ) f o f T To
QP =
8.86 T To
ln1 (t1 , T1 )
ln 2 (t 2 , T2 ) 101.6 T To
S
Dh3 sin 2 P
*
12
L
Dh2 sin2 h P
QP =
2 s 2 2m * L
S
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POLYMER PHYSICS - Fall 2009-Edge
2
E h
2
m = bulk D2 tan DB DS
4
sin
QD = 1/2 2 D2 Nh cos sin
F2
P=
2
9 2 r1 r 2
2
P=
8LQ
R4
F2
P=
2
9 2 r1 r 2
2
P=
8LQ
R4
t
F0 =
x2
DR
vf
v0
Rf
BR
R0
X
Z
R0
yield 0.028 ETensile
F
R0 f z
Q
R0 3 p
P
Q
Q =V A
n 1
= T
Miscellaneous
E E f v f Em vm
vf
v
1
m
E
Ef
Em
k
=
Cp
4 h2
t cooling =
h0
B R DR
hf
E 2 (1 2 ) B
DV
= m T
Blow Molding
E 2 (1 ) G
Bt = B2
p
Re =
EMA 6165 - EXAM 2
8 Tm Tw
ln 2
TD TW
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