Modeling polymer crystallisation induced by a moving heat sink

Soft Matter ◽

10.1039/d0sm02237c ◽

2021 ◽

Author(s):

Sabin Adhikari ◽

Ahana Purushothaman ◽

Alejandro A. Krauskopf ◽

Christopher Durning ◽

Sanat K. Kumar ◽

...

Keyword(s):

Stefan Problem ◽

Heat Sink ◽

Polymer Melt

Recent experiments have shown that polymer crystallisation can be used to “move” and organize nanoparticles. As a first effort at modelling this situation we consider the classical Stefan problem modified for a polymer melt but driven by a heat sink.

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Polymer Morphology Revealed by Staining Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098204 ◽

1981 ◽

Vol 39 ◽

pp. 340-341

Author(s):

A. C. Reimschuessel ◽

V. Kramer

Keyword(s):

Polymer Melt ◽

Nylon 6 ◽

Morphological Features ◽

Negative Staining ◽

Polymer Morphology ◽

Crystallizable Polymer ◽

Staining Techniques ◽

Long Chain

Staining techniques can be used for either the identification of different polymers or for the differentiation of specific morphological domains within a given polymer. To reveal morphological features in nylon 6, we choose a technique based upon diffusion of the staining agent into accessible regions of the polymer.When a crystallizable polymer - such as nylon 6 - is cooled from the melt, lamellae form by chainfolding of the crystallizing long chain macromolecules. The regions between adjacent lamellae represent the less ordered amorphous domains into which stain can diffuse. In this process the lamellae will be “outlined” by the dense stain, giving rise to contrast comparable to that obtained by “negative” staining techniques.If the cooling of the polymer melt proceeds relatively slowly - as in molding operations - the lamellae are usually arranged in a radial manner. This morphology is referred to as spherulitic.

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The effect of an aluminum heat-sink layer on the laser-induced amorphization of SiOx/TeGeSn/SiOx phase-change recording films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154846 ◽

1989 ◽

Vol 47 ◽

pp. 574-575

Author(s):

Matthew R. Libera ◽

Martin Chen

Keyword(s):

Thin Film ◽

Phase Change ◽

Heat Sink ◽

Multilayer Film ◽

Glassy Phase ◽

Film Structure ◽

Glass Forming ◽

Active Storage ◽

Dielectric Layers ◽

Amorphous States

Phase-change erasable optical storage is based on the ability to switch a micron-sized region of a thin film between the crystalline and amorphous states using a diffraction-limited laser as a heat source. A bit of information can be represented as an amorphous spot on a crystalline background, and the two states can be optically identified by their different reflectivities. In a typical multilayer thin-film structure the active (storage) layer is sandwiched between one or more dielectric layers. The dielectric layers provide physical containment and act as a heat sink. A viable phase-change medium must be able to quench to the glassy phase after melting, and this requires proper tailoring of the thermal properties of the multilayer film. The present research studies one particular multilayer structure and shows the effect of an additional aluminum layer on the glass-forming ability.

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