222
S. Napolitano
Abbreviations
BDS Broadband Dielectric Spectroscopy
C
Capacitance
G
Crystal growth rate
h
Film thickness
LN2 Liquid nitrogen
PEO Polyethylene oxide
PEN Poly(ethylene 2,6-naphthalate)
PET
Poly(ethylene terephthalate)
PHB Poly(3-hydroxy butyrate)
PLLA Poly(L-lactide acid)
t cry
Crystallization time
TFA Trifluoroacetic acid
T g
Glass transition temperature
T m
Melting temperature
ε
Dielectric strength
ξ
Stokes–Einstein exponent
1 Introduction
Nanoconfinement affects the crystallization of polymers [1]. For long chains, same
as in the case of smaller molecules [2], the complex set of mechanisms leading to
the formation of ordered structures is affected by both finite size [3] and interfacial
effects [4]. The former case is related to a change occurring in a given property, e.g.,
the crystal growth rate, when reducing a size of the system from infinite to below a
threshold value, related to a length scale of the system, e.g., a multiple of the lamellar
thickness. Interfacial effects, instead, arise from a perturbation in material properties
because of the presence of an interface with another medium. This is, for example,
the case of density which might significantly vary in proximity of adsorbing walls
or at the free surface with air.
The literature on the impact of nanoconfinement on the crystallization of polymers is impressively large [5–15]. Most of the work has, however, focused on the
analysis of changes in crystalline morphology and perturbations in the crystal growth
rate, by means of different optical and scanning probe microscopies. This type of
investigation has brought to a tremendous advancement of our knowledge on crystallization: investigation of polymers confined at the nanoscale level permitted us to test
the robustness of theories of crystal formation. Working with confined geometries
has, in fact, allowed reaching regimes of undercooling, [16] and peculiar nucleation
densities otherwise not achievable in bulk [3, 17].
Despite this progress, little is known on how molecular mobility affects crystallization in bulk and at the nanoscale. This is not related to the lack of interest
S. Napolitano
Abbreviations
BDS Broadband Dielectric Spectroscopy
C
Capacitance
G
Crystal growth rate
h
Film thickness
LN2 Liquid nitrogen
PEO Polyethylene oxide
PEN Poly(ethylene 2,6-naphthalate)
PET
Poly(ethylene terephthalate)
PHB Poly(3-hydroxy butyrate)
PLLA Poly(L-lactide acid)
t cry
Crystallization time
TFA Trifluoroacetic acid
T g
Glass transition temperature
T m
Melting temperature
ε
Dielectric strength
ξ
Stokes–Einstein exponent
1 Introduction
Nanoconfinement affects the crystallization of polymers [1]. For long chains, same
as in the case of smaller molecules [2], the complex set of mechanisms leading to
the formation of ordered structures is affected by both finite size [3] and interfacial
effects [4]. The former case is related to a change occurring in a given property, e.g.,
the crystal growth rate, when reducing a size of the system from infinite to below a
threshold value, related to a length scale of the system, e.g., a multiple of the lamellar
thickness. Interfacial effects, instead, arise from a perturbation in material properties
because of the presence of an interface with another medium. This is, for example,
the case of density which might significantly vary in proximity of adsorbing walls
or at the free surface with air.
The literature on the impact of nanoconfinement on the crystallization of polymers is impressively large [5–15]. Most of the work has, however, focused on the
analysis of changes in crystalline morphology and perturbations in the crystal growth
rate, by means of different optical and scanning probe microscopies. This type of
investigation has brought to a tremendous advancement of our knowledge on crystallization: investigation of polymers confined at the nanoscale level permitted us to test
the robustness of theories of crystal formation. Working with confined geometries
has, in fact, allowed reaching regimes of undercooling, [16] and peculiar nucleation
densities otherwise not achievable in bulk [3, 17].
Despite this progress, little is known on how molecular mobility affects crystallization in bulk and at the nanoscale. This is not related to the lack of interest