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Research Interests
Dynamic light scattering; positron
annihilation lifetime spectroscopy; rheology of
macromolecules in solution and bulk; polymer surfactants;
viscoelastic behavior of biopolymer solutions.
Overview of Research
We seek to understand, at the molecular
level, diverse aspects of the thermodynamic and transport
properties of polymeric materials. We apply the dynamic
light scattering (DLS) technique to obtain detailed
information regarding the molecular hydrodynamic properties
of polymer chains in solution and bulk. Most recently, we
utilized DLS to measure the intrinsic viscosities of liquid
crystal polymers dissolved in thermotropic nematic solvents,
and to prove that these data are uniquely sensitive to the
LCP architecture and conformation. Rheological studies with
S. Q. Wang were able to demonstrate the unique transient
flow signatures of flow-aligning and tumbling nematics, as
well as the fact that these behaviors could be manipulated
by dissolution of LCPs, in accordance with predictions of
hydrodynamic theory. With J. D. McGervey and R. Simha, we
have applied positron annihilation lifetime spectroscopy
(PALS) to characterize free volume in amorphous polymers. We
demonstrated a quantitative relationship between the
fractional free volume obtained from PALS analysis and
independent estimates from bulk volume via statistical
mechanical theory. With S. D. Hudson, the influence of a
block copolymer (bcp) on the morphology of immiscible
polymer blends was explored. We showed that enthalpic
interactions can dramatically enhance the emulsifying power
of the bcp and observed such effects as emulsification
failure when the swelling of the bcp in the major phase is
too strong, and the induction of phase inversion when the
bcp swelling in the minor phase is very strong. With J.
Blackwell, we investigated relationships between structure
and rheology of two high molecular weight glycoproteins:
proteoglycan, which forms the shock-absorbing matrix between
the load-bearing collagen fibers in cartilage and tendon,
and mucin, which is the principal component of the mucus
which coats the lungs and gastric tracts. Combining DLS and
rheological measurements, we deduced distinct gelation
mechanisms for these two species. Proteoglycan behaves as a
highly-charged spheroid and gels through a particle-jamming
process at high volume fractions. Mucins behave as stiff
linear 'hairy-rod' chains, and gel via a microphase
separation mechanism.
Current Activity
With S. Nazarenko (Univ. of Southern
Mississippi), PALS studies were performed on a series of
well-characterized poly(ethylene terephthalate) (PET)
samples. Systematic divergences in the orthopositronium
(o-Ps) annihilation lifetimes, 3, and intensities, I3, were
observed, when comparing melt-crystallized and
cold-crystallized PET as a function of crystallinity. These
divergences were traced to distinct characteristic values
for 3 and I3 in the rigid and mobile amorphous phases (RAF
and MAF). Utilizing independent information on the volume
fractions of RAF andMAF, quantitative analysis of the o-Ps
annihilation parameters was achieved.
With J. Lal (Argonne National Lab),
small-angle neutron scattering studies were performed on a
side-chain liquid crystal polymer (SCLCP) dissolved in
deuterated pentylcyanobiphenyl (d-5CB). The results show
that the SCLCP has a quasi-spherical, slightly prolate
shape. This result is consistent with deductions from
electrorheological (ER) studies and serves to validate
hydrodynamic theory. Rheological studies with S. J. Rowan
are exploring the thixotropic behavior of
metallo-supramolecular polymer gels, formed through
self-assembly of a ditopic ligand via metal-ligand binding
interactions, Zn(II) ions acting as a chain extender, and
La(III) as a trifunctional crosslinker. These gels are
highly brittle, undergoing a dramatic transition to a
Newtonian sol at a very small yield strain, and rapidly
recovering the gel structure when the stress is removed.
Laser scanning confocal microscopy indicates the gelation
occurs via the formation and flocculation of
semi-crystalline colloidal particles.
With A. Sirivat (Chulalongkorn
University, Thailand), electrorheological (ER) properties of
particulate dispersions of conducting polymers are in
progress. Perchloric acid-doped polythiophene and the
emeraldine base of polyaniline each show excellent ER
properties. The creep response of these ER fluids indicates
a smooth evolution from linear to nonlinear viscoelastic
solid, then to plastic solid, and finally to yielding and
viscous flow as the applied stress is increased at relative
to the electric field strength. When the field is switched
off a residual structure remains, whose yield stress
increases with the strength of the applied field and
particle concentration. When the applied stress exceeds the
yield stress of the residual structure, fast, fully
reversible switching of the ER response is obtained.
The rheology and properties of zeolite
materials made via controlled hydrolysis of silatrane and
alumatrane, as sources of silica and alumina, respectively,
are being studied in collaboration with S. Wongkasemjit (Chulalongkorn
University, Thailand) and E. Gulari (University of
Michigan). Our results show that silatrane or silatrane
mixed with alumatrane can be conveniently used as starting
materials for sol–gel processing. Both silatrane and
alumatrane have trialkoxyamine ligands that coordinate with
metal atoms to form moderately inert complexes in aqueous
solutions. Using sodium hydroxide as the hydrolytic agent,
and treating the amorphous gel under hydrothermal
conditions, a variety of crystalline aluminosilicates or
zeolites have been obtained in high purity, with small
particle sizes, narrow size distribution, and few defects.
Recent Publications
“Rheological Properties and Conformation
of a Side-Chain Liquid Crystal Polysiloxane Dissolved in a
Nematic Solvent,” Y. Zhao, S. Dong, A. M. Jamieson, X. Hu,
J. Lal, S. Nazarenko, and S. J. Rowan, Macromolecules,
38,
5205 (2005).
“Electrorheological Properties of
Polyaniline Suspensions: Field-Induced Liquid to Solid
Transition and Residual Gel Structure,” P. Hiamtup, A.
Sirivat, and A. M. Jamieson, J. Colloid Interface Sci.,
295,
270 (2005).
“VS-1 Zeolite Synthesized Directly from
Silatrane,” P. Phiriyawirut, A. M. Jamieson b, S.
Wongkasemjit, Micropor. and Mesopor. Mat., 77, 203 (2005).
“Viscoelastic Properties of Ceria Gel,”
N. Phonthammachai, M. Rumruangwong, S. Jitkanka, E. Gulari,
A. M. Jamieson, and S. Wongkasemjit, Mat. Sci. Forum,
480,
355 (2005).
“Electrical Properties of a Novel Lead
Alkoxide Precursor,” N. Tangboriboon, K. Pakdeewanishsukho,
A. M. Jamieson, A. Sirivat, and S. Wongkasemjit, Mat. Chem.
Phys., 98, 138 (2006).
“Crystallization and Catalytic Activity
of High Titanium Loaded TS-1 Zeolite,” N. Phonthammachai, K.
Pakdeewanishsukho, A. M. Jamieson, A. Sirivat, and S.
Wongkasemjit, Mat. Chem. Phys., 97, 458 (2006).
“Synthesis of Fe-loaded MFI zeolite using
silatrane as. precursor and its CO activity,” N.
Kritchayanon, N.Thanabodeekij, S. Jitkarnka , A. M. Jamieson
, and S. Wongkasemjit, Appl. Organomet. Chem. 20, 155
(2006).
“Preparation and
Characterization of Polyaniline/Chitosan Blend Film,” T. Thanpitcha, A. Sirivat, A. M.
Jamieson, and R. Rujiravanit, Carbohydrate Polymers,
64, 560 (2006).
“Polymer-Surfactant Complex Formation and its Effect on Turbulent Wall Shear Stress,” S. Suksamranchit, A. Sirivat, and A. M. Jamieson, J. Colloid Interface Sci., 294, 212 (2006).
“Influence of Polyethylene Oxide on the Rheological Properties of Semidilute, Wormlike Micellar Solutions of Hexadecyltrimethylammonium Chloride and Sodium Salicylate,” S. Suksamranchit, A. Sirivat, and A. M. Jamieson, J. Colloid. Interface Sci., 304 (2006).
“Understanding the Gelation and Stimuli-Responsive Nature of a Class of Metallo-Supramolecular Polymers,” Wengui Weng, J. Benjamin Beck, Alexander M. Jamieson, and Stuart J. Rowan, J. Amer. Chem. Soc., 128, 11663 (2006).
“Creep and Recovery Behaviors of a Polythiophene-based Electrorheological Fluid,” Datchanee Chotpattananont, Anuvat Sirivat, and Alexander M. Jamieson, Polymer, 47, 3568 (2006).
“Conformation of Comb-like Liquid Crystal Polymers in Isotropic Solution Probed by Small-Angle Neutron Scattering,” Y. Zhao, A. M. Jamieson, B. G. Olson, N. Yao, S. Dong, S. Nazarenko, X. Hu, J. Lal, J. Polym. Sci. Polym. Phys., 44, 2412 (2006).
Awards
1989, Fellow of the American Physical
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