Personal Statement – V9
Feng Linqian
I’m an undergraduate student majoring in polymer material science and engineering from BUCT
in China. I want to apply for the Ph.D program of University of Texas–Austin.
Background & Advantage
(1) To obtain a clear thinking in research, I focus on polymer physics and polymer chemistry
learning. In the project “PI/Ladder-like polysiloxanes(LPS) composite films preparation”, I chose
LPS for its ladder structure can maintain the overall structre and properties even when meet
partial chain rupture. I still remember Flory-Huggins model extended my interests into
compatibility thermodynamics of blend polymer, and also provided me the fundamental
understanding of phase disengagement. I got A in statistics which supports me the main
theoretical basis and mathematics tools of polymer physics. Gaussian distribution model and
G-matrix extended me from macroscopical models into quantum statistical mechanics, explaining
the relationship between polymeric properties and molecular chain structures.
(2) I obtained good experimental skills and ideas from polymer physics experiment （A） and
polymer specialty experiment （A）. In my research, I used DSC-TGA to conclude that oxidative
decomposition of PI in the surface composite layers was catalyzed by the newly born ZnO
nanoparticles from the exothermic peak.
Experience & Propose
(1) In order to broaden my knowledge in the field of functional polymer design and synthesis, I
joined
the
research
of
“synthesize
temperature-sensitive
magnetic
poly(N-isopropylacrylamide)/Fe3O4 hollow microspheres” when I was a junior. Considering
hydrophilicity of Fe3O4 nanoparticles (under 15nm) prepared by coprecipitation method, I used
oleic acid to make Fe3O4 stably disperse on the oil-water interface before polymerization, and
embed in the layers of hollow misrocpheres via inverse emulsion
Compared with
PNIPAM/Fe3O4 core-shell structure, hollow microspheres structure have higher drug-loading and
less reaction between shell layers and drugs. The principle difficulties for synthesizing this hollow
microspheres structure center on controlling double-bond grafted on Fe3O4(chose KH550) to
overcome the block of Fe3O4 and maintaining activity of initiator in oxidation-reduction radical
system.
(2) In my team research “preparation of PI/ZnO composite films with photoluminescence
properties”, we fabricated them via ion-exchange technique, incorporating zinc ions into PI film
surface modified layers and thermally treating the precursor films in air atmosphere. We also
researched on the effect of initial zinc ion loading on film morphology, photoluminescence (PL)
properties and thermal properties of the PI/ZnO nanocomposite films by SEM, TEM, PL spectra,
TGA and DSC. Compared with widely used in-situ process, which always leads to uncontrollable
agglomeration and inhomogeneous dispersion of the ZnO nanoparticles in polymer matrix, the
new and convenient ion exchange technique make ZnO form on both surfaces of the PI film,
obtain the excellent mechanical properties and controllable properties of the composite films.
Plan & Goal
Thermoset-based silsesquioxanes or MOS nanocomposites is challenging because of the
agglomeration and interface problems arised from significant difference in surface energy and big
specific surface area of nanostructure when synthesizing nanocomposite. Thus, in my Ph.D
research, I want to approach the problems from 3 aspects. In characterization skills, I am
interested in sophisticated array of modern surface spectroscopies, including surface Raman
spectroscopy; I also want to improve the design of in situ and intercalated hybrud methods, as
well as design of new small molecules with dilfunctionality which can link reinforcement and
matrix by each reactive point, in synthesis field.
这三个方面的方法怎么解决前面提到的问题呢,没有写清楚
Drugs entrapped in polymer matrices can be released via passive diffusion of the drug from a
static polymer scaffold. Enhanced diffusion can be attained with swelling of the polymer matrix,
providing a mechanism for stimuli-responsive release, which I am interested in. Many functional
durg deliveries with core-shell structure is prepared by incorporating nanoparticles, while hollow
microspheres structure is difficult in embeding nanoparticles into matrix. Emulsion method also
result in microsize, which tends to be blocked by nanoparticles. Thus, in my Ph.D research, I plan
to improve template method, seek for new emulsion and W 1/O/W 2 methods.
这一段你想研究的问题是什么？写的不明确
I would like to apply for Ph.D program of material science and engineering in University of
Texas–Austin, not only for your strong strength in structural and biological composites, what is
more important, several professors’ research area are those I am interested in.Dr. Tess J. Moon,.
Dr.Keith P. Johnston and Dr.Don Paul’s interest in Biomedical nanotechnology , polymer blends
and nanocomposites, such as nano-filled polymers, active nanostructures and their application.