TY - JOUR A1 - Hättig, J. A1 - Bräuer, W. A1 - Pretsch, Thorsten T1 - Ein Kunststoff, der sich erinnert - Einsatzchancen von thermoplastischem Polyurethan mit Formgedächtnis N2 - Ein neu entwickeltes thermoplastisches Polyurethan (TPU) ist alles andere als „vergesslich". Formteile aus dem Material lassen sich in einer temporären Form fixieren und wieder nahezu in ihre ursprüngliche Gestalt zurückverwandeln. Dieser Formgedächtniseffekt hat gute Anwendungschancen - vom Marken- und Produktschutz über den Maschinen- und Automobilbau, bis hin zur Freizeit- und Spielzeugindustrie. KW - Thermoplastisches Polyurethan (TPU) KW - Desmopan DP 2795A SMP KW - Formgdächtnispolymer KW - Shape memory polymer KW - Smarte Etiketten KW - Schaltbare Etiketten KW - Produkt und Markenschutz KW - Smartphone KW - QR code KW - Färbeverfahren KW - Guest diffusion KW - TPU Folie KW - Selbst-aufrichtende Treibhäuser KW - Folientunnel PY - 2013 SN - 0344-4570 VL - 4 SP - 92 EP - 94 PB - Vereinigte Fachverl. CY - Mainz AN - OPUS4-28081 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pretsch, Thorsten A1 - Ecker, Melanie A1 - Schildhauer, Markus A1 - Maskos, Michael T1 - Switchable information carriers based on shape memory polymer N2 - Herein we demonstrate the realization of a new technological concept, which enables the use of shape memory polymers (SMPs) as switchable information carriers. At first, we applied a surface-specific dyeing process based on 'guest-diffusion' on two sophisticated polymeric host materials, including a thermoplastic poly(ester urethane) SMP and a thermoset epoxy-based SMP. Upon drying, self-assembly of the dye molecules inside the polymer surfaces occurred, resulting in homogeneous color penetration depths of about 100 µm. Subsequently, the colored surfaces were patterned with quick response (QR) codes. For this purpose, laser ablation was used. The resulting cavity depth was exceeding the color penetration depth. This assured sufficient surface contrast and rendered the QR codes machine-readable. In a progressive approach, two thermo-mechanical functionalization protocols were designed in accordance with the thermal properties of the polymers. As a result of programming, the tag prototypes were converted into stable, temporary shapes with non-decodable QR code information. When thermally triggering the shape memory effect on the functionalized tags, we verified the mostly complete recovery of the polymer surface and the associated restoration into the almost original shape. As such, the QR code could again precisely be read out. We anticipate that tagging products with these information carriers is helpful for the purpose of secure one-time identification. KW - Shape memory polymer KW - Epoxy-based polymer KW - Poly(ester urethane) KW - Thermo-responsive polymer KW - Laser ablation KW - Laser marking KW - QR code KW - Functionalized tags KW - Tag technology KW - Smart tagging KW - Switchable information carrier KW - Authentification KW - Identification KW - Surface-specific dyeing KW - Guest diffusion PY - 2012 DO - https://doi.org/10.1039/c2jm16204k SN - 0959-9428 SN - 1364-5501 VL - 22 IS - 16 SP - 7757 EP - 7766 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-25737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ecker, Melanie A1 - Pretsch, Thorsten T1 - Durability of QR code carriers based on shape memory polymer N2 - The surface of a shape memory poly(ester urethane) (PEU) was either black- or blue-colored to obtain switchable quick response (QR) codes after laser engraving and thermomechanical functionalization (programming). The investigation of dye and functional stability against UVA and hydrolytic aging (at 23 and 60 °C) gave that contrast decline due to dye decolorization (in case of UVA aging) or distinct dye diffusion (in case of hydrolytic aging) finally inhibited the QR code readability. By contrast, PEU as marked base material could be adequately fixed and recovered even when the Michelson contrast in the QR code region was falling in course of aging below a crucial value of 0.1, whereupon the QR code was no longer readable. Hence, we concluded that under the given experimental conditions the decisive parameter for tag applicability was the surface contrast. T2 - SMASIS2012 - ASME 2012 Conference on smart materials, adaptive structures and intelligent systems CY - Stone Mountain, Georgia, USA DA - 2012-09-19 KW - Shape memory polymer KW - Durability KW - QR code KW - Poly(ester urethane) KW - Product and brand protection applications KW - Counterfeit-proof labels KW - Tags KW - QR code carriers KW - Switchable information carriers KW - Functionalization KW - Surface-specific dyeing PY - 2012 IS - SMASIS2012-8038 SP - 1 EP - 8 PB - ASME AN - OPUS4-27884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mirtschin, Nikolaus A1 - Pretsch, Thorsten T1 - Miniturization of QR code carriers based on shape memory polymer N2 - Here we present a suitable tag prototype with phasesegregated poly(ester urethane) (PEU) as base material for effectively switching a quick response (QR) code in its surface from non-readable to readable. In comparison with recently introduced tags (different geometry) we minimized the thickness from plaque (2 mm) to foil size (0.5 mm) and reduced the lateral QR code length from 15 to 5 mm. Subsequent to surface-dyeing by means of guest diffusion, the QR code was laser-engraved. The implementation of thermo-mechanical functionalization via tensile deformation and cooling resulted in the formation of stable shapes, which exceeded the barrier of QR code readability at an elongation of 20%. Once functionalized, tags were switched on demand by heating. As such the recovery of the PEU was accomplished and the QR code could again be read out. QR code carriers based on shape memory polymer can be used in product and brand protection applications. T2 - SMASIS2012 - ASME 2012 Conference on smart materials, adaptive structures and intelligent systems CY - Stone Mountain, Georgia, USA DA - 2012-09-19 KW - Shape memory polymer KW - QR code KW - Poly(ester urethane) KW - Product and brand protection applications KW - Counterfeit-proof labels KW - Tags KW - Switchable information carriers KW - Functionalization KW - Miniaturization KW - Surface-specific dyeing KW - Victoria Blue B PY - 2012 N1 - Geburtsname von Mirtschin, Nikolaus: Fritzsche, N. - Birth name of Mirtschin, Nikolaus: Fritzsche, N. IS - SMASIS2012-8036 SP - 1 EP - 8 PB - ASME AN - OPUS4-27886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ecker, Melanie A1 - Pretsch, Thorsten T1 - Freely configurable functionalization tool for switchable information carriers N2 - The selective compression of quick response (QR) and Data Matrix code carriers based on shape memory polymer (SMP) with a freely configurable steel ball type indenter and adjacent thermo-mechanical shape fixing gave notched, room temperature (23 °C) stable, temporary shapes with non-decipherable codes. The microscopic investigation of cryomicrotome sections unveiled indentation-related shape fixities of about 90%. Independent of the selected two-dimensional code, the triggering of the SM effect resulted in sufficient shape recoveries to restore the code readability so that a maximum number of characters including 122 for a QR code (version 7) and 112 in case of a Data Matrix code (version 12) could be read with a scanning and decoding device. Due to the large number of difficult to copy shapes with on demand releasable information, SMPs may serve as viable information carriers for product and brand protection applications. T2 - 3rd WMRIF Workshop for young materials scientists CY - Pathumthani, Thailand DA - 2012-08-28 KW - Shape memory polymer KW - QR code KW - Data matrix code KW - Poly(ester urethane) KW - Product and brand protection applications KW - Tags KW - Switchable information carriers KW - Freely configurable functionalization KW - Selective deformation KW - Steel ball type indenter KW - Spherical indentation KW - Cryomicrotome sections KW - Surface-specific dyeing PY - 2012 SP - 1 EP - 10(?) AN - OPUS4-27887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bothe, Martin A1 - Mya, K.Y. A1 - Lin, E.M.J. A1 - Yeo, C. C. A1 - Lu, X. A1 - He, C. A1 - Pretsch, Thorsten T1 - Triple-shape properties of star-shaped POSS-polycaprolactone polyurethane networks N2 - Here, we present an investigation of the triple-shape properties of star-shaped polyhedral oligomeric silsesquioxane-poly(ε-caprolactone) polyurethanes (SPOSS-PUs), which have three-dimensional network structures. In a typical 'triple-shape functionalization process', mostly consisting of two tensile deformations at different temperatures, chain immobilization of the polymer network component poly(ε-caprolactone) (PCL) was successfully realized first through crystallization and then through vitrification. Subsequently, large parts of the respective strains were released under stress-free recovery conditions. The two-fold fixed ('programmed') specimens responded to heating with two independent length contractions (switching steps); the first shape change was associated with PCL devitrification and the second one with the melting of hitherto crystalline PCL. It was revealed that the triple-shape properties of SPOSS-PU networks considerably depend on PCL network chain length. When applying exactly the same 'triple-shape creation procedure', larger strain releases were detected in the first transition for polymers with a higher PCL network chain length, whereas the second transition was more accentuated for SPOSS-PU networks with a shorter PCL chain length. In the course of thermo-mechanical cycling, the formation of a neck during the second tensile deformation was repeatedly detected for SPOSS-PUs with higher PCL network chain length; in the subsequent recovery process the specimens even exhibited the highest total strain recoverability. Finally, gradual strain release could be achieved at temperatures below the PCL melting transition through the selection of up to four temperature holding steps, at which every time stable shapes were formed. KW - Shape memory polymer KW - Active polymer KW - Triple-shape polymer KW - Hybrid star-shaped polymer KW - POSS-polycaprolactone polyurethanes KW - Thermo-mechanical properties PY - 2012 DO - https://doi.org/10.1039/c1sm06474f SN - 1744-683X VL - 8 IS - 4 SP - 965 EP - 972 PB - RSC Publ. CY - Cambridge AN - OPUS4-25260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten T1 - Neue Möglichkeiten mit Formgedächtnispolymeren T2 - Intelligente Materie - Funktionswerkstoffe und smarte Oberflächen für Design und Produktentwicklung, TSB Technologiestiftung Berlin CY - Berlin, Germany DA - 2013-01-23 PY - 2013 AN - OPUS4-27441 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hättig, J. A1 - Bräuer, W. A1 - Pretsch, Thorsten T1 - Scharfes Gedächtnis einprogrammiert - Thermoplastisches Polyurethan N2 - Auch Kunststoffe können sich erinnern. Das zeigt das Beispiel eines neuen thermoplastischen Polyurethans. Das Formgedächtnispolymer kann vorübergehend in einem deformierten Zustand fixiert und dann wieder nahezu in seine ursprüngliche Gestalt zurückverwandelt werden. Einsatzchancen hat es unter anderem im Markenschutz und Maschinenbau sowie in der Textil-, Sport-, Freizeit- und Spielzeugindustrie. KW - Thermoplastisches Polyurethan (TPU) KW - Poly(ester urethan) KW - Desmopan KW - Formgedächtnispolymer KW - Shape memory polymer KW - Folientunnel KW - Smarte Etiketten KW - TPU Etiketten KW - Fälschungssicher KW - Smartphone KW - QR code PY - 2013 UR - http://www.kunststoffe.de/KU111219 SN - 0023-5563 VL - 1 SP - 56 EP - 59 PB - Hanser CY - München AN - OPUS4-27650 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hättig, J. A1 - Bräuer, W. A1 - Pretsch, Thorsten T1 - Programmed to have a keen memory - Thermoplastic polyurethane N2 - Plastics can also remember things. This is made clear by a new thermoplastic polyurethane. The shape memory polymer can be temporarily fixed in a deformed state and then converted back almost entirely into its original shape. Potential applications exist in trademark protection and mechanical engineering as well as in the textile, sports, leisure and toy industries. KW - Thermoplastic polyurethane KW - Poly(ester urethane) KW - Desmopan KW - Shape memory polymer KW - Self-deployable structures KW - Smart tags KW - TPU labels KW - Greenhouse-like film tunnels KW - QR codes KW - Product and brand protection PY - 2013 UR - http://www.kunststoffe-international.com/PE111219 SN - 1862-4243 VL - 1 SP - 39 EP - 41 PB - Hanser CY - München AN - OPUS4-27651 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten A1 - Ecker, Melanie T1 - Deformable QR Codes with Shape Memory Functionality T2 - E-MRS 2012 Spring Meeting, Symposium Q CY - Strasbourg, France DA - 2012-05-14 PY - 2012 AN - OPUS4-25891 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten A1 - Bothe, Martin T1 - Actuation behavior of a thermo-responsive elastomer under constant load T2 - E-MRS 2012 Spring Meeting, Symposium Q CY - Strasbourg, France DA - 2012-05-14 PY - 2012 AN - OPUS4-25892 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hättig, J. A1 - Bräuer, W. A1 - Pretsch, Thorsten T1 - Programmierbares TPU für den Produktschutz - Etiketten mit Gedächtnis N2 - Mit Formgedächtnispolymeren auf Basis von TPU sind Bauteile spritzgieß- oder extrudierbar, die sich vorübergehend durch eine gezielte thermomechanische Behandlung in einer anderen temporären Form fixieren und stabilisieren lassen. Damit können Informationen gespeichert, vorübergehend sicher verschlüsselt und als Quick Response (QR)-Codes mit schaltbarer Lesbarkeit auf TPU-Etiketten eingraviert werden. KW - Thermoplastisches Polyurethan (TPU) KW - Poly(ester uretahne) KW - Desmopan KW - Formgedächtnispolymer KW - Shape memory polymer KW - Smarte Etiketten KW - TPU Etiketten KW - Fälschungssicher KW - Smartphone KW - QR code KW - Färbeverfahren KW - Guest diffusion KW - TPU Folien KW - Technologieentwicklung PY - 2012 SN - 0032-1338 VL - 1 IS - 12 SP - 40 EP - 42 PB - Hüthig CY - Heidelberg AN - OPUS4-27776 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten T1 - Degradation, functional stability and protection of a shape memory polymer T2 - 1st International Workshop for Young Scientists CY - Tsukuba, Japan DA - 2008-07-22 PY - 2008 AN - OPUS4-17942 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten T1 - Shape Memory Polymers - Characteristics, Ageing & Testing T2 - IMRE Seminar, Institute of Materials Research and Engineering CY - Singapore DA - 2008-11-21 PY - 2008 AN - OPUS4-18459 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten A1 - Müller, Werner T1 - Geosynthetic drain elements of landfill capping systems: long-term water flow capacity and long-term shear strength T2 - 8th International Conference on Geosynthetics CY - Yokohama, Japan DA - 2006-09-18 PY - 2006 AN - OPUS4-16416 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten ED - Teruo Kishi, ED - Thomas Böllinghaus, ED - Masaki Kitagawa, ED - Jürgen Lexow, T1 - Degradation, Functional Stability and Protection of a Shape Memory Polymer T2 - 1st World Materials Research Institutes Forum (WMRIF), Workshop for Young Materials Scientists CY - Tsukuba, Japan DA - 2008-07-22 KW - Formgedächtnispolymer KW - Poly(ester urethan) KW - Thermomechanische Eigenschaften KW - Hydrolyse PY - 2008 SN - 978-4-9900563-3-9 SP - XXX-1 - XXX11 AN - OPUS4-17819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecker, Melanie A1 - Pretsch, Thorsten T1 - Durability of switchable QR code carriers under hydrolytic and photolytic conditions N2 - Following a guest diffusion approach, the surface of a shape memory poly(ester urethane) (PEU) was either black or blue colored. Bowtie-shaped quick response (QR) code carriers were then obtained from laser engraving and cutting, before thermo-mechanical functionalization (programming) was applied to stabilize the PEU in a thermo-responsive (switchable) state. The stability of the dye within the polymer surface and long-term functionality of the polymer were investigated against UVA and hydrolytic ageing. Spectrophotometric investigations verified UVA ageing-related color shifts from black to yellow-brownish and blue to petrol-greenish whereas hydrolytically aged samples changed from black to greenish and blue to light blue. In the case of UVA ageing, color changes were accompanied by dye decolorization, whereas hydrolytic ageing led to contrast declines due to dye diffusion. The Michelson contrast could be identified as an effective tool to follow ageing-related contrast changes between surface-dyed and laser-ablated (undyed) polymer regions. As soon as the Michelson contrast fell below a crucial value of 0.1 due to ageing, the QR code was no longer decipherable with a scanning device. Remarkably, the PEU information carrier base material could even then be adequately fixed and recovered. Hence, the surface contrast turned out to be the decisive parameter for QR code carrier applicability. KW - Beständigkeit KW - Thermoplastisches Polyurethan (TPU) KW - Poly(ester urethan) KW - Formgedächtnispolymer KW - UVA Alterung KW - Hydrolytische Alterung KW - Michelson contrast KW - Shape memory polymer KW - Smarte Etiketten KW - TPU Etiketten KW - Fälschungssicher KW - Smartphone KW - QR code KW - Polymerveredlung KW - Färbeverfahren KW - Lasergravur PY - 2013 DO - https://doi.org/10.1088/0964-1726/22/9/094005 SN - 0964-1726 SN - 1361-665X VL - 22 IS - 9 SP - 094005-1 - 094005-10 PB - Institute of Physics Publ. CY - Bristol AN - OPUS4-28986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pretsch, Thorsten T1 - Polymere mit Formgedächtnis T2 - WTT-Kooperationsforum, Produkt- und Plagiatsschutz, Berlin Partner für Wirtschaft und Technologie CY - Berlin, Germany DA - 2013-09-20 PY - 2013 AN - OPUS4-29107 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecker, Melanie A1 - Pretsch, Thorsten T1 - Multifunctional poly(ester urethane) laminates with encoded information N2 - Solvent-cast films from shape memory poly(ester urethane) (PEU) containing different weight contents of microencapsulated thermochromic pigments (T-PIGs) were prepared by drying in air. Spectrophotometric investigations unveiled that gradual loading with T-PIG black resulted in continuous darkening of the films up to filler contents of 20 wt%, accompanied by a steady enhancement of thermochromic properties. Taking this composition as standard, PEU films equipped with T-PIG black, blue and red were deposited atop PEU plaques to obtain laminate structures. Herein, the cover layer thickness (100 ± 5 µm) and the good dispersion of T-PIGs inside the polymer matrix were verified by scanning electron microscopy. Machine-readable information carriers were prepared by laser engraving quick response (QR) codes into the cover layer of the laminates and subsequently cutting cuboidal samples therefrom. Finally, thermo-mechanical programming of the QR code carriers was applied to randomly distort the code patterns, thus rendering them unreadable. Upon heating, surface decolorization and shape recovering occurred; during the ensuing cooling, the surface color and contrast reappeared whereupon the QR codes could be read out. Spectrophotometric, calorimetric and thermo-mechanical investigations gave evidence that the color switching temperature of the T-PIGs roughly coincided with the melting temperature of the ester-based switching segment and thus with the activation temperature of the shape memory effect. Apart from that unique functionality, manifold design concepts may render information carriers difficult-to-copy. Therefore, we anticipate tremendous potential as anti-counterfeiting technology. KW - Stimuli-responsive polymer KW - Shape memory polymer KW - Poly(ester urethane) KW - Microencapsulated KW - Thermochromic pigments KW - Thermo-responsive KW - Thermochromic KW - Shape memory effect KW - Polymer bilayer structure KW - Polymer laminate KW - Paste KW - Gluing KW - Spectrophotometric investigations KW - Calorimetric studies KW - Thermo-mechanical investigations KW - Information carrier KW - Anti-counterfeiting technology KW - Difficult-to-copy PY - 2014 DO - https://doi.org/10.1039/c3ra45651j SN - 2046-2069 VL - 4 IS - 1 SP - 286 EP - 292 PB - RSC Publishing CY - London AN - OPUS4-29652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bothe, Martin A1 - Pretsch, Thorsten T1 - Bidirectional actuation of a thermoplastic polyurethane elastomer N2 - Herein, we report on how to teach a thermoplastic polyurethane elastomer completely stress-free, bidirectional motion. Briefly spoken, we applied training, consisting of extensive tensile deformation in the specimen's viscoelastic state, initiating deformation-induced crystallization. Once unloaded, thermo-reversible specimen expansion and contraction could be detected. Following the microstructural evolution of such a trained specimen by in situ wide-angle X-ray scattering gave evidence for progressive growth of oriented crystallites during cooling. Upon heating, crystallite melting resulted in structural disorder. Beyond this, modification of the training method was used to introduce a geometrically more complex crystalline order. Here, actuation in the form of a decrease and an increase in sample thickness and specimen twisting and untwisting were witnessed. The novel semi-crystalline polymer actuator highlights an enormous potential for realizing versatile reversible shape changes in elastomers. KW - Bidrectional actuation KW - Thermoplastic polyurethane elastomer KW - Shape memory polymer KW - Training KW - Reversible shape changes KW - In situ wide-angle X-ray scattering KW - Hermann's orientation function KW - Mechanical properties KW - Phase change KW - Polymorphism KW - Poly(ester urethane) KW - Poly(1,4-butylene adipate) KW - Semi-crystallinity KW - Stimuli-sensitive polymer KW - Two-way actuator KW - Two-way shape memory KW - Microscopic model PY - 2013 DO - https://doi.org/10.1039/c3ta13414h SN - 2050-7496 SN - 2050-7488 VL - 1 IS - 46 SP - 14491 EP - 14497 PB - RSC CY - London [u.a.] AN - OPUS4-29641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -