Effect of pigment concentration on mechanical properties of polycarbonate

This experimental study deals with the influence of pigments on the mechanical properties of polymeric polycarbonate material Lexan 923c, which is commonly used in industry and is being processed with injection technology. This material was stained with three different pigments from Lifokolor. It was also stained with 6 different concentrations of selected pigments. Emphasis was placed on measuring the tensile strength, impact strength and hardness of polyurethane mixtures. © The Authors, published by EDP Sciences, 2017.ERDF, European Regional Development Fun

Effect of pigment concentration on mechanical properties and on color stability of polycarbonate

This experimental study deals with the influence of pigments on the mechanical properties of polymeric polycarbonate material Lexan 923c, which is commonly used in industry and is being processed with injection technology. This material was stained with three different pigments from Lifokolor. It was also stained with 6 different concentrations of selected pigments. Emphasis was placed on measuring the tensile strength, impact strength and hardness of polymer mixtures. It also deals with the influence of pigment concentration on colorimetric properties and the concentration of pigment value at which the material needs to be colored. Colorimetric properties and reflective spectra of different concentrations were also measured. © 2017, World Scientific and Engineering Academy and Society. All rights reserved.IGA/FT/2017/010, MŠMT, Ministerstvo Školství, Mládeže a Tělovýchovy; MSMT-7778/2014, ERDF, European Regional Development Fun

The influence of regression curve parameters of creep behaviour on measured data prediction

This study deals with the study of the influence of regression curve parameters on prediction of possibilities of measured data. In this study, the necessary introduction to polymer materials issues and their material structure which influences their physical and mechanical properties, is described. Thereafter, the method of testing materials using device DMA which enables this measurement is presented. In the next part, this measured data are processed using creep modulus in which regression curves are applied. In the final part of this study, the influence of individual parameters of the regression curve on their process during the prediction is described. The study will prove the inconsiderable influence especially the last parameter of the regression curve equation and its significant influence on measured data prediction. © The Authors, published by EDP Sciences, 2017

Correlation of the prediction curve of the creep behaviour of polymeric materials

This study deals with the study corellation of regression curve parameters on the prediction of possibilities of measured data. In this study, the necessary introduction of polymeric materials and their material structure, which influences their physical and mechanical properties is described. Thereafter, the method of testing materials using the DMA device which enables this measurement is presented. In the next section, these measured data are processed by a creep module in which the regression curve methods and their match with the measured data are applied. In the final part of the thesis is evaluated the conformity of the measured data with the data obtained from the regression curve. © 2017, World Scientific and Engineering Academy and Society. All rights reseved

The influence of injection molding on tensile and tear properties of EPDM rubber

In industry the control of physical properties of rubber products produced by injection molding is mostly performed on testing samples produced by another method-cutting out of a compression molded plate according to ISO standard. This different method of producing testing samples and final products may have a different impact on physical properties. The paper compares and evaluates the selected physical properties (tensile strength, modulus of elasticity and tear strength) of EPDM rubber samples prepared by the standard method (cutting out of a compression molded plate) and injection molded samples and finally third method-cutting out of an injection molded plate. The results have shown that using the injection molded samples we will achieve more objective results mainly to determine the tear strength. In the case of tensile strength, the differences are not so significant. © 2018, World Scientific and Engineering Academy and Society. All rights reserved

The Influence of runner system on production of injection molds

This experimental study describes the influence of runner system on rheological properties during the injection molding process. Economic effects on the amount of production are discussed as well. Autodesk Moldflow Synergy 2016 (Moldflow) was used for the study of the injection process. Three suggestions of the runner system, cold runner system, hot runner system and the combination of cold hot runner system have been promoted. These three variants underwent the rheological and economic analysis. As a result, recommendations for the application of the runner system for the required amount of production have been suggested.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; TBU in Zlin [IGA/FT/2016/010

The Effect of Injection Molding on Physical Properties of EPDM Rubber

The paper a part of research aimed at the alternative of preparing test samples by injection molding. Such an alternative could bring more objective results in the field of testing samples produced in the same technology. The research is aimed at changing the preparation of rubber testing samples-replacing the standard method according to ISO 23529 by the injection method, especially with the use of rubber compounds for injection molding. This article compares and evaluates the selected physical properties (tensile strength and tear strength) of EPDM rubber injection molded samples with samples prepared by the standard method-cutting out of a compression molded plate. The results have shown that using the injection molded samples we will achieve more objective results mainly to determine the tear strength. In the case of tensile strength, the differences are not so significant. © 2018 The Authors, published by EDP Sciences.European Regional Development Fund under the project CEBIA-Tech Instrumentation [CZ.1.05/2.1.00/19.0376]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Program [L01303 (MSMT-7778/2014)]; Internal Grant Agency of TBU in Zlin [IGA/FT/2018/012

Influence of length of glass fibers in recycled polypropylene on tensile properties

The purpose of this article is to show the influence of grinded glass fibers in polymer material. Tested samples were processed by injection molding. Waste from this production was subsequently ground and a mixture was obtained with different size of crushed material. These particles contains glass fibers of similar length as the specific size of particle. Thus very small particles contain very short fibers. Investigation was carried out by testing tensile properties on material polypropylene with 30% glass fibers. Testing was conducted at ambient temperatures. The effect of reprocessing of material is mainly represented by fiber shortening. As a result, considerable reduction of tensile properties can be observed. The reduction is most evident in the modules of elasticity and ultimate tensile strength.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089

Mechanical properties of modified HDPE by ionizing radiation after temperature load under and above the pure HDPE melting temperature

Radiation processing of polymers is a well-established and economical commercial method of precisely modifying the properties of polymers, especially mechanical properties. The mechanical properties of modified HDPE samples by beta rays were measured at the ambient temperature and after temperature load under and above the pure HDPE melting temperature. The tested samples showed significant changes of mechanical behaviour before and after temperature load. From this point of view, new applications could also be seen in areas with service temperatures higher than their former melting point

Polymer fluidity influenced by type and amount of filler

Delivery of polymer melts into the mold cavity is the most important stage of the injection molding process. This paper shows the influence of cavity surface roughness and technological parameters on the flow length of polymers into mold cavity. Application of the measurement results may have significant influence on the production of shaping parts of the injection molds especially in changing the so far used processes and substituting them by less costly production processes which might increase the competitiveness of the tool producers and shorten the time between product plan and its implementation. This research focused into the influence of technological parameters on filling of the injection mold cavity and the flow length respectively.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; TBU in Zlin [IGA/FT/2016/010