Polymer blends with ordered distribution of conductive filler

This review highlight approaches to the formation of an ordered distribution of conductive filler in polymer blends. This distribution leads to a significant decrease of the percolation threshold in the polymer mixture, i.e. to a decrease in the critical concentration of the filler, at which the transition of the system from a non-conductive to a conductive state occurs. This improves the mechanical properties of the composition and its processability. It is shown that the ordered structure of the filler is formed in the polymer blend upon mixing the components in the melt under the action of three factors - thermodynamic (the ratio between the values of the interfacial tension of the filler-polymer A and filler-polymer B, as well as between polymers A and B), kinetic (the ratio between viscosities of polymer components A and B) and technological (the intensity and temperature of processing, as well as the order of introduction of a filler into a heterogeneous polymer matrix, which can enhance or suppress the effect of thermodynamic or kinetic factors). On the example of the works performed by the author on mixtures of thermoplastics filled with electrically conductive carbon fillers such as carbon black and carbon nanotubes, as well as a metal filler - dispersed iron, with the involvement of literature data on filled polymer blends, the influence of each of the factors on the formation of an ordered structure of the conducting phase in polymer blends is shown.

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Piezoresistive bond lines for timber construction monitoring—experimental scale-up

Wood Science and Technology ◽

10.1007/s00226-021-01305-6 ◽

2021 ◽

Author(s):

Christoph Winkler ◽

Stefan Haase ◽

Ulrich Schwarz ◽

Markus Jahreis

Keyword(s):

Electrical Contact ◽

Scale Up ◽

Strain Analysis ◽

Conductive Filler ◽

Bond Line ◽

Wood Products ◽

Image Correlation ◽

Test Sequence ◽

Strain Sensing ◽

Electrically Conductive

AbstractSeveral laboratory studies and experiments have demonstrated the usability of polymer films filled with electrically conductive filler as piezoresistive material. Applied to adhesives, the glue lines of wood products can achieve multifunctional—thus bonding and piezoresistive/strain sensing—properties. Based on critical load areas in timber constructions, upscaled test setups for simplified load situations were designed, especially with regard to a stress-free electrical contact. In a second step, another upscaling was done to small glulam beams. Based on an experimental test sequence, the piezoresistive reactions as well as the behaviour until failure were analysed. The results show in all cases that a piezoresistive reaction of the multifunctionally bonded specimens was measurable, giving a difference in the extent of relative change. Additionally, measured phenomena like inverse piezoresistive reactions, electrical resistance drift and the absence of a piezoresistive reaction were discussed, based on additional strain analysis by digital image correlation. A model of macroscopic and microscopic strains influencing the piezoresistive reaction of the electrically conductive bond line in wood was used to explain all experimental results. Finally, a first scale-up of piezoresistive bond lines from laboratory samples to glulam beams was possible and successful.

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Mechanical and Electrical Performance of Flexible Polymer Film Designed for a Textile Electrically-Conductive Path

Materials ◽

10.3390/ma14092169 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2169

Author(s):

Agnieszka Tabaczyńska ◽

Anna Dąbrowska ◽

Marcin Masłowski ◽

Anna Strąkowska

Keyword(s):

Ionic Liquid ◽

Ionic Liquids ◽

Surface Resistance ◽

Conductive Filler ◽

Extrusion Process ◽

Electrical Performance ◽

Electrically Conductive ◽

Non Invasive ◽

Flexible Polymer ◽

The Stability

Electro-conductive paths that are mechanically resistant and stable during simulated aging cycles are promising, in relation to the non-invasive application in e-textiles in our everyday surroundings. In the paper, an analysis of the influence of electro-conductive filler, as well as ionic liquid on surface resistance is provided. Authors proved that depending on the tested variant, obtained surface resistance may vary from 50 kΩ (when 50 phr of Ag and [bmim][PF6] ionic liquid applied) to 26 GΩ (when 25 phr of Ag and [bmim][PF6] ionic liquid applied). The samples were also evaluated after simulated aging cycles and the stability of electric properties was confirmed. Moreover, it was proved that the addition of ionic liquids reduced the resistance of vulcanizates, while no significant influence of the extrusion process on conductivity was observed.

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Structure and mechanical properties of heterogeneous polymer blends

Journal of Applied Polymer Science ◽

10.1002/app.1995.070551002 ◽

1995 ◽

Vol 55 (10) ◽

pp. 1375-1383 ◽

Cited By ~ 7

Author(s):

M. Kozlowski

Keyword(s):

Mechanical Properties ◽

Polymer Blends ◽

Heterogeneous Polymer

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Gas transport in heterogeneous polymer blends

Journal of Membrane Science ◽

10.1016/s0376-7388(00)80161-1 ◽

1983 ◽

Vol 13 (2) ◽

pp. 197-204 ◽

Cited By ~ 12

Author(s):

J.A. Barrie ◽

J.B. Ismail

Keyword(s):

Polymer Blends ◽

Gas Transport ◽

Heterogeneous Polymer

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Combined AFM/Raman Studies of Heterogeneous Polymer Materials

MRS Advances ◽

10.1557/adv.2016.412 ◽

2016 ◽

Vol 1 (25) ◽

pp. 1859-1864 ◽

Cited By ~ 1

Author(s):

Marko Surtchev ◽

Mark Wall ◽

Sergei Magonov

Keyword(s):

Surface Morphology ◽

Polymer Blends ◽

Heterogeneous Systems ◽

Polymer Materials ◽

Raman Mapping ◽

Immiscible Polymer Blends ◽

Immiscible Polymer ◽

Heterogeneous Polymer ◽

Comprehensive Characterization

ABSTRACTCompositional imaging of several immiscible polymer blends was examined with the combination of AFM-based mechanical and electric modes with chemically-specific Raman mapping. Results showed that these methods substantially complement each other in comprehensive characterization of surface morphology by helping to identify a composition of top surface and sub-surface materials in polymer heterogeneous systems.

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Characterization of heterogeneous polymer blends by two-dimensional proton spin diffusion spectroscopy

Macromolecules ◽

10.1021/ma00143a020 ◽

1985 ◽

Vol 18 (1) ◽

pp. 119-122 ◽

Cited By ~ 141

Author(s):

P. Caravatti ◽

P. Neuenschwander ◽

R. R. Ernst

Keyword(s):

Polymer Blends ◽

Spin Diffusion ◽

Proton Spin ◽

Two Dimensional ◽

Heterogeneous Polymer

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Regulation of Electrical, Thermal and Physical Properties of Composites Based on Carbon-Modified Portland Cement Materials

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.264 ◽

2020 ◽

Vol 299 ◽

pp. 264-269

Author(s):

K.V. Tikhomirova ◽

A.Yu. Semeykin

Keyword(s):

Portland Cement ◽

Thermal Characteristics ◽

Water Repellent ◽

Mechanical And Thermal Properties ◽

Cement Composites ◽

Carbon Filler ◽

Electrically Conductive ◽

Conductive Phase ◽

Carbon Fillers ◽

Adhesion Work

The article discusses aspects of the production and use of composites based on carbon-filled cement matrices. It is shown that the main problem in the technology of such composites is the regulation of the processes of structure formation and uniform distribution of the electrically conductive phase throughout the volume, to ensure stable electrical characteristics of the material. A method for solving the problem of improving the physical, mechanical and thermal properties of carbon-filled Portland cement composites by regulating the surface properties of carbon fillers, in order to reduce their concentration in the composite and the content of the aqueous phase, is proposed. It is shown that the modification of the carbon filler surface using the water-repellent agent PMS-20 reduces the adhesion work at the interface, which makes it possible to reduce the concentration of the electrically conductive phase in the composite and improve its physical, mechanical and thermal characteristics.

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