Crystallization of Polymers Under 1D
Confinement
Simone Napolitano
Abstract Crystallization of polymers becomes tremendously sluggish upon
confinement at the nanoscale level, where a severe reduction in the overall crystallization rate is commonly observed. In extreme cases, below a critical thickness (usually
on the order of few tens of nm) polymer chains do not crystallize. This phenomenon
has attracted a considerable technological interest. Being able to suppress, or at least
to reduce, the crystallization rate would yield, for example, a tremendous increase
in safety of those amorphous drugs where the crystalline form has non-negligible
toxicity, and a neat improvement the lifetime of polymer-based nanodevices where
the presence of crystals affects materials properties. While most of the work on crystallization on confinement focused on the investigation of the formation of crystalline
structures, less is known on the molecular origin of the confinement effects of the
slower kinetics. Unveiling the nature of the changes in crystallization rate requires
the use of experimental approaches, as broadband dielectric spectroscopy, permitting to achieve information also on molecular relaxation processes taking place in
the noncrystalline component. In this chapter, we will summarize the outcome of
the investigation of the cold crystallization of thin polymer films (1D confinement)
via Broadband Dielectric Spectroscopy (BDS). After discussing the experimental
protocol necessary to perform such measurements, we will show how BDS can be
employed to disentangle the nucleation and the growth component of the kinetics.
Finally, we will discuss on the interplay between chain adsorption and crystal growth
in thin films and introduce a general picture of the competition between the two
phenomena affecting mass transport at the nanoscale level.
Keywords Thin polymer films · 1D confinement · Dielectric spectroscopy ·
Segmental mobility · Crystallization · Irreversible adsorption
S. Napolitano (B)
Polymer and Soft Matter Dynamics, Experimental Soft Matter and Thermal Physics (EST),
Faculté des Sciences, Université Libre de Bruxelles (ULB), 1050 Ixelles, Brussels, Belgium
e-mail: snapolit@ulb.ac.be
© Springer Nature Switzerland AG 2020
T. A. Ezquerra and A. Nogales (eds.), Crystallization as Studied
by Broadband Dielectric Spectroscopy, Advances in Dielectrics,
https://doi.org/10.1007/978-3-030-56186-4_9
221
Confinement
Simone Napolitano
Abstract Crystallization of polymers becomes tremendously sluggish upon
confinement at the nanoscale level, where a severe reduction in the overall crystallization rate is commonly observed. In extreme cases, below a critical thickness (usually
on the order of few tens of nm) polymer chains do not crystallize. This phenomenon
has attracted a considerable technological interest. Being able to suppress, or at least
to reduce, the crystallization rate would yield, for example, a tremendous increase
in safety of those amorphous drugs where the crystalline form has non-negligible
toxicity, and a neat improvement the lifetime of polymer-based nanodevices where
the presence of crystals affects materials properties. While most of the work on crystallization on confinement focused on the investigation of the formation of crystalline
structures, less is known on the molecular origin of the confinement effects of the
slower kinetics. Unveiling the nature of the changes in crystallization rate requires
the use of experimental approaches, as broadband dielectric spectroscopy, permitting to achieve information also on molecular relaxation processes taking place in
the noncrystalline component. In this chapter, we will summarize the outcome of
the investigation of the cold crystallization of thin polymer films (1D confinement)
via Broadband Dielectric Spectroscopy (BDS). After discussing the experimental
protocol necessary to perform such measurements, we will show how BDS can be
employed to disentangle the nucleation and the growth component of the kinetics.
Finally, we will discuss on the interplay between chain adsorption and crystal growth
in thin films and introduce a general picture of the competition between the two
phenomena affecting mass transport at the nanoscale level.
Keywords Thin polymer films · 1D confinement · Dielectric spectroscopy ·
Segmental mobility · Crystallization · Irreversible adsorption
S. Napolitano (B)
Polymer and Soft Matter Dynamics, Experimental Soft Matter and Thermal Physics (EST),
Faculté des Sciences, Université Libre de Bruxelles (ULB), 1050 Ixelles, Brussels, Belgium
e-mail: snapolit@ulb.ac.be
© Springer Nature Switzerland AG 2020
T. A. Ezquerra and A. Nogales (eds.), Crystallization as Studied
by Broadband Dielectric Spectroscopy, Advances in Dielectrics,
https://doi.org/10.1007/978-3-030-56186-4_9
221