The Only Good Rodlike Polymer is a
Dead Rodlike Polymer
Honoring Professor Wilmer G. Miller
on the Occasion of his Retirement
Friday, May 11, 2001
University of Minnesota
http://russo.chem.LSU.edu/WilmerFest
There once was a theorist from France
who wondered how molecules dance.
“They’re like snakes,” he observed,
“As they follow a curve, the large ones
Can hardly advance.”
D ~ M -2
de Gennes
P.G. de Gennes
Scaling Concepts in Polymer Physics
Cornell University Press, 1979
6/27/2016
Entanglement in solution?
Collander
To isolate spaghetti in "solution" with a fork is
difficult: hydrodynamic interactions interfere
with entanglement. After solvent is drained to
obtain a "melt" the entire blob is easily handled.
6/27/2016
“This area is likely to remain fruitful, at least on
the theoretical side: experimentally, one could
argue that sufficient data exist to
test any model thoroughly.”
Physical Chemistry of Polymers:
Entropy, Interactions, and Dynamics
Lodge & Muthukumar, J. Phys. Chem. 1996, 100, 13275-13292
6/27/2016
Doi-Edwards-Onsager Reference Volumes for Rods
 = number density = # of rods per unit volume
d
LC formation
* = 4/A2  5/dL2
L
Reduced # Density
/*  dL2/5
2
3
dL
L

1
3
L
L3  1
6/27/2016

A2 
1
2
dL
dL2  1

dL2
1
A2
A2  1
4
Coloring Molecules—Apologies to Dick Stein
Small Angle Neutron Scattering
Forced Rayleigh Scattering
Fluorescence Photobleaching Recovery
Index-matched DLS
match solvent & polymer refractive index
can't do in aqueous systems
Depolarized DLS
works for optically anisotropic probes
works for most matrix polymers
6/27/2016
Modulation FPR Device a’la Lanni & Ware
PA
TA/PVD
PMT
*
OS
*
D
S
*
M
DM
OBJ
RR
*
M
L
AOM
6/27/2016
Labeling Does Not
Bug the Helix




Computer Simulation
Intrinsic Viscosity
Static Light Scattering
Dynamic Light
Scattering
 Phase boundary
determinations
 Temperaturedependent studies
6/27/2016
traces to zborg\pblg26k
16
LPBLG-20,000
D in DMF at 40oC
m
D corrected to 25oC in pyridine
12
m
D in pyridine at 25oC
s
10
s
m
D and D /10-7cm2-s-1
14
8
6
4
2
0
0.0
0.1
0.2
c/g-mL-1
6/27/2016
0.3
0.4
traces to zborg5pblgc
s
D /cm2-s-1
10-6
10-7
LPBLG-20,000
LPBLG-36,000
LPBLG-89,000
LPBLG-103,000
LPBLG-232,000
10-8
0.01
0.1
c/g-mL-1
Up arrows denote the condition dL2 = 1. Down arrrows show the condition c = [h]-1.
6/27/2016
dL2
0
2
4
6
8
10
12
14
16
1.2
DMF
1
)/(D /Do)
LPBLG
s
(D /Do
LPBLG
0.6
0.4
0.1
s
(D /Do
1.13 + 0.04
s
0.8
s
)/(D /Do)
DMF
1.0
LPBLG- 20,000
LPBLG- 36,000
LPBLG- 89,000
LPBLG-103,000
LPBLG-232,000
0.01
0.1
0.2
0.0
0.0
0.5
1.0
1.5
/*
6/27/2016
1
/*
2.0
2.5
3.0
Beginning to look like real PChem, only not boring.
6/27/2016
Doing our Part to Keep the “A” in LSU A&M
Seedlings
Sick Plants 
And close-up
of mosaic
pattern.
6/27/2016
6/27/2016
An ear of corn has about as many kernels as TMV
has protein subunits (ca. 2130). The protein
subunits enfold a spiral-wound strand of RNA which
will encode the next generation. TMV is more
extended than an ear of corn.
6/27/2016
Contrast
4
0.040
0.035
3
0.030
/Hz
0.025
0.020
0.015
2
0.010
DC Signal
0.005
0.000
0
2
4
6
8
10
12
14
K2 / 105cm-2
1
0
0
200
400
600
t/s
6/27/2016
800
1000
6/27/2016
6/27/2016
Dtracer self of TMV vs. cTMV
Source: Cush Monthly Report (5/1/01)
7
1/L3
1/dL2
5
4
3
D
self
/ 10 -8 cm 2 s -1
6
2
1
0.1
1
10
c
6/27/2016
TMV
/ mg mL-1
100
Fuzzballs
a silica interior and synthetic
homopolypeptide exterior.
Silica (SiO2) core
typically 200 nm diameter
Homopolypeptide Shell
typically 100 nm thick
Colloidal Crystals (PCBL Shell)
Why Study?
~ 2 mm
~ 0.5 m
SiO2
Beautiful!
Fun supramolecular synthesize &
characterize from nm to mm.
Sufficiently
dense devices,
suspensions
Applies to optical
assemble
colloidal
crystals.paint,
betterinto
lasers,
pigment-free
With“smart
a sizecolloids”,
that matches
that muscle,
of
artificial
visible light, diffraction results.
separations technology
Domains with different
orientations result in different
and quite pure colors.
Helical homopolypeptide shell
Transmittance measured on monochromatorequipped microscope
3.5
Transmitted Light Intensity vs. Wavelength
PCBL/Silica Composite Particle
3.0
Imaged region includes 3 domains
568 nm
2.5
I
2.0
593 nm
615 nm
1.5
1.0
0.5
0.0
400
500
600
700
/nm
FWHM of line is ~ 16 nm, comparable to
typical interference filters of conventional design
Fuzzballs: nm to mm
vis
Helical polypeptides
SiO2
Colloidal crystal
•diffract visible light
•ours will be smart!
Colloidal chain
6/27/2016
•chiral stationary phase?
•can they swim?
•Can they be hollow?
NSF IGERT




NSF
Integrative Graduate Education Research Training
NSF Agency-wide, $2.7M two-stage competition
19 funded from a pool of about 300
Some other IGERT’s

Biogeochemical Research Initiative for Education (Penn State)

Integrating Formal and Empirical Methods in the Cognitive
Science of Language (Johns Hopkins)

Astrobiology: Life in and beyond Earth's Solar System
(Washington)

Human Dimensions of Social and Aquatic System Interactions
(Wisconsin--Madison)
LSU’s IGERT
Teaching Craft for Macromolecular
Creativity
 The first and only IGERT in Macromolecules or Polymers.
 An experiment in graduate education.
 Departments: Biology, Chemistry, Chemical Engineering, Mechanical
Engineering, Physics, Textiles, Veterinary Medicine
 Yes, there must be good research--but everyone has this!









Leverage teaching excellence
Apprentice/Artisan/Craftsperson Ladder: Hands First
Faculty researchers, not financiers of research
Faculty teams fund high-risk projects neither could do alone
Ethics training plus community service
Faculty work with students side-by-side
Integrated, multi-department, lab/lecture 4-course curriculum
Minigrants / Finishing School / Off-campus Advisors
Off-campus: MPI-Mainz, METU/Turkey/ DSM/Geleen /Many Others
Inhibition of Amyloid Plaques
NIH In$titute for Aging
6/27/2016
Ph.D. Grandchildren of WGM
NAME
YEAR
WORKS AT
WHERE
1989
PAPERS
PUBLISHED
4
Mark DeLong
Union Carbide
Mazidah
Mustafa
Zimei Bu
1990
3
Housewife
S. Charleston
WV
Detroit, MI
1994
6
Yale & NIST
NH & DC
Debbie Tipton
1995
3
Chevron
Orange, TX
Daewon Sohn
1995
6
Seoul, Korea
Keunok Yu
1995
3
Lucille SmithWright
1999
2+
Han-Yang
University
Kunsan
Universisty
USGS
Kunsan, Korea
Baton Rouge
Randy Cush, Garrett Doucet, Sibel Turksen, Nadia Edwin
6/27/2016
Observe! Wonder! Have Fun!
NSF
6/27/2016
Who did the work
•Zimei Bu (YaleNIST)
•Randy Cush (Yr4)