Fachgebiet Kunststofftechnikhttps://kobra.uni-kassel.de:443/handle/123456789/20130718430402024-03-29T01:41:43Z2024-03-29T01:41:43ZModification of self-reinforced composites (SRCs) via film stacking processJakob, FabianPollmeier, JoshuaBisevac, SinanHeim, Hans-Peterhttps://kobra.uni-kassel.de:443/handle/123456789/155732024-03-18T17:05:29Z2022-02-25T00:00:00ZThis work presents the mechanical behavior of self-reinforced composites (SRCs) manufactured and modified via film stacking. For modification, interleaved films made of polypropylene (PP), a thermoplastic elastomer and a polyolefin engage were combined in different ways to induce the elastic modifier into the matrix material. The content of modifier was also varied in two ways. First, the films were produced out of a single material and second out of a compound. So, the same content of modifier was implemented in two different ways. It is shown that, in case of this research, only the kind of modifier and the content but not the way of implementation are responsible for the mechanical behavior of SRCs. It is shown that the modification can adjust the tensile strength, tensile stiffness and impact properties in a broad range. It is also shown that different mechanical properties of the composite can be predicted by a regression model that uses the Shore A hardness and the content of modifier.
2022-02-25T00:00:00ZJakob, FabianPollmeier, JoshuaBisevac, SinanHeim, Hans-PeterThis work presents the mechanical behavior of self-reinforced composites (SRCs) manufactured and modified via film stacking. For modification, interleaved films made of polypropylene (PP), a thermoplastic elastomer and a polyolefin engage were combined in different ways to induce the elastic modifier into the matrix material. The content of modifier was also varied in two ways. First, the films were produced out of a single material and second out of a compound. So, the same content of modifier was implemented in two different ways. It is shown that, in case of this research, only the kind of modifier and the content but not the way of implementation are responsible for the mechanical behavior of SRCs. It is shown that the modification can adjust the tensile strength, tensile stiffness and impact properties in a broad range. It is also shown that different mechanical properties of the composite can be predicted by a regression model that uses the Shore A hardness and the content of modifier.Investigation of the adhesive strength in a combined compaction and back-injection process to produce back-injected self-reinforced composites (SRCs)Jakob, Fabian SimonGothe, MarcelGansiniec, FabianHeim, Hans-Peterhttps://kobra.uni-kassel.de:443/handle/123456789/155722024-03-18T16:34:27Z2022-03-08T00:00:00ZThis publication investigates the adhesion between an injection molded component and a self-reinforced composite (SRC) produced in a combined compaction and back-injection process to produce back-injected self-reinforced composites. To study the influence of the process, the parameters barrel temperature, time of injection, and tool temperature were varied. In addition, samples were taken at different positions along the flow path. In light of the orthotropic material behavior of SRCs, investigations were conducted to see whether different loading cases lead to different mechanical behavior. Shear-off and pull-off tests revealed a different strength as a function of the loading type. In the shear-off tests, a mean strength of 11.37 MPa was recorded over the entire test series, while the measured mean strength in the pull-off tests is considerably lower, 4.04 MPa. The type of failure is determined with the aid of SEM images, and the influence of the microstructure of the thermoplastic fibre materials on the adhesion is set out. It is shown that, as of a sufficiently high level of adhesion, failure occurs within the fibres.
2022-03-08T00:00:00ZJakob, Fabian SimonGothe, MarcelGansiniec, FabianHeim, Hans-PeterThis publication investigates the adhesion between an injection molded component and a self-reinforced composite (SRC) produced in a combined compaction and back-injection process to produce back-injected self-reinforced composites. To study the influence of the process, the parameters barrel temperature, time of injection, and tool temperature were varied. In addition, samples were taken at different positions along the flow path. In light of the orthotropic material behavior of SRCs, investigations were conducted to see whether different loading cases lead to different mechanical behavior. Shear-off and pull-off tests revealed a different strength as a function of the loading type. In the shear-off tests, a mean strength of 11.37 MPa was recorded over the entire test series, while the measured mean strength in the pull-off tests is considerably lower, 4.04 MPa. The type of failure is determined with the aid of SEM images, and the influence of the microstructure of the thermoplastic fibre materials on the adhesion is set out. It is shown that, as of a sufficiently high level of adhesion, failure occurs within the fibres.Climatic Ageing of Components of Polymer Based Electrochromic DevicesHeim, Hans-PeterDesjean, Alinehttps://kobra.uni-kassel.de:443/handle/123456789/155712024-03-18T16:10:04Z2013-09-09T00:00:00ZCombining a shading function and a polycarbonate window displays an attractive alternative to the currently employed glass roof in vehicles. However, the ageing of such a device must be investigated before any application. Therefore, our investigations focus on the ageing of the components of a polycarbonate based electrochromic device. The optical, electrical, mechanical and electrochemical properties of the ion storage layer as well as the substrate will be assessed after storage in a climate with a high humidity and high temperature level.
2013-09-09T00:00:00ZHeim, Hans-PeterDesjean, AlineCombining a shading function and a polycarbonate window displays an attractive alternative to the currently employed glass roof in vehicles. However, the ageing of such a device must be investigated before any application. Therefore, our investigations focus on the ageing of the components of a polycarbonate based electrochromic device. The optical, electrical, mechanical and electrochemical properties of the ion storage layer as well as the substrate will be assessed after storage in a climate with a high humidity and high temperature level.UV Surface Treatment of Polycarbonate for Adhesion Improvement to Liquid Silicone Rubber (LSR)Hartung, MichaelNikousaleh, Mohammad AliRüppel, AnnetteGiesen, Ralf-UrsHeim, Hans-Peterhttps://kobra.uni-kassel.de:443/handle/123456789/155562024-03-19T16:09:21Z2018-01-01T00:00:00ZThe adhesion of self-adhesive liquid silicone rubbers to thermoplasts is only possible for a few selected material combinations without a surface pretreatment. A UV pretreatment is effective for polycarbonate and short irradiation periods are sufficient. To clarify the required irradiation conditions that result in an improvement of adhesion, the varying irradiation conditions were assessed. FTIR-ATR spectroscopy was used for surface analysis to characterize the change in the polymer surface.; Die Haftung von selbsthaftenden Flüssigsilikonkautschuken auf Thermoplasten ist ohne Oberflächen-vorbehandlung nur für einige Materialkombinationen möglich. Für Polycarbonat erweist sich eine UV-Vorbehandlung als effektiv, wobei sehr kurze Bestrahlungszeiten ausreichen. Zur Aufklärung der be-nötigten Bestrahlungsbedingungen, die zur Verbesserung der Haftung führen, wurden Bestrahlungs-versuche durchgeführt und ausgewertet. Zur Oberflächenanalytik wurde die FTIR-ATR-Spektroskopie eingesetzt, um die Veränderung der Polymeroberfläche zu charakterisieren.
2018-01-01T00:00:00ZHartung, MichaelNikousaleh, Mohammad AliRüppel, AnnetteGiesen, Ralf-UrsHeim, Hans-PeterThe adhesion of self-adhesive liquid silicone rubbers to thermoplasts is only possible for a few selected material combinations without a surface pretreatment. A UV pretreatment is effective for polycarbonate and short irradiation periods are sufficient. To clarify the required irradiation conditions that result in an improvement of adhesion, the varying irradiation conditions were assessed. FTIR-ATR spectroscopy was used for surface analysis to characterize the change in the polymer surface.
Die Haftung von selbsthaftenden Flüssigsilikonkautschuken auf Thermoplasten ist ohne Oberflächen-vorbehandlung nur für einige Materialkombinationen möglich. Für Polycarbonat erweist sich eine UV-Vorbehandlung als effektiv, wobei sehr kurze Bestrahlungszeiten ausreichen. Zur Aufklärung der be-nötigten Bestrahlungsbedingungen, die zur Verbesserung der Haftung führen, wurden Bestrahlungs-versuche durchgeführt und ausgewertet. Zur Oberflächenanalytik wurde die FTIR-ATR-Spektroskopie eingesetzt, um die Veränderung der Polymeroberfläche zu charakterisieren.