1 semi-crystalline polymer morphologies and their hierarchical morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Semi-CrystallineHelical StructureChain FoldingSemi-Crystalline Fibrillar GrowthSpherulitic, shish-kabob, epitaxial surface nucleation, Crystalline OrientationLamellar OrientationMacroscopic Orientation
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Paul Phillips 1990 Review
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Paul Phillips 1990 Review
Rigid, semi-Rigid, FlexiblePolymer Chains
On melting the entropy gain is smallbecause the crystallizing units are
chemically bound. The random coilstate is seen classically as the highestentropy state. For rigid polymers the
ground state may be a lower entropy state.
Kevlar
Polythiophene
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Paul Phillips 1990 Review
Tacticity
Tacticity governs the helical structure
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Chain Folding and Crystallization
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
n-alkane boiling and melting points
“n”
Boili
ng
(to
p)
or
Melt
ing
(b
ott
om
) P
oin
t
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
“Crystals act like crosslinks in rubber” P. Phillips 1990
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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http://www.eng.uc.edu/~gbeaucag/Classes/MorphologyofComplexMaterials/Chapter2html/Chapter2.html
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Solution Crystallization
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Why do Chains Fold?
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Why do Chains Fold?
For an infinite crystal V/S is very large and we can ignore the surfaceAt the equilibrium melting point ΔG = 0 so:
substituting in the first equation,
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Why do Chains Fold?
For a lamellar crystal S is 2R2 and V is tR2
At a pseudo-equilibrium point where the crystal has a finite thickness of t and a depressedmelting point, T
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Why do Chains Fold?
or
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Hoffman-Weeks Plot
http://www.eng.uc.edu/~gbeaucag/Classes/MorphologyofComplexMaterials/Chapter2html/Chapter2.html
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Diffusion of impurities versus growth rate of crystallization front
J = -D dc/dx for flux of impuritiesG = linear growth rate of crystal
D/G = δ, the Keith-Padden δ-parameter
This determines the coarseness of the spherulite (lateral size)
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
Add a first stem, then subsequent stems.
First stem and subsequent stems add
2b0σl and b0σl
To the free energy (cost to make a surface)
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
First stem:
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Hoffman-Lauritzen Secondary Nucleation Theory
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Primary Nucleation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Primary Nucleation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Spherulites
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Primary Nucleation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
http://www.eng.uc.edu/~gbeaucag/Classes/MorphologyofComplexMaterials/Chapter2html/Chapter2.html
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
Non Crystallographic Branching
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Semi-Crystalline Polymer Morphologiesand their Hierarchical Morphologies
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Spherulitic Growth Rate
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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Avrami Equation
http://scholar.lib.vt.edu/theses/available/etd-051799-162256/unrestricted/polyimide2.pdf
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