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Polyolefins (POs) are currently the most widely used engineering plastics due to their relatively low cost, durability, and ease of processing. A feature such as inertness makes polyolefins suitable for applications such as food packaging and medical devices. For the purpose of this study, polyethylene (PE) with good rigidity, hardness, impact strength, environmental stress cracking resistance, and excellent processability, and polypropylene (PP), with high fluidity and very good transparency, were selected polyolefins [1,2]. Knowing that most of the polymer applications are strongly dependent on the initial state of the products, i.e., their morphology, thermal properties, and crystallinity, it is possible to obtain a great variety of morphologies and supermolecular formations by varying different conditions in the preparation process, e.g. cooling conditions during the crystallization process from the melt. One of the aims of this work was to compare the results obtained for two different methods of sample preparation, quenching, and slow cooling. Initial preparation was performed for selected POs by rapid quenching in ice water and slow air cooling after compression molding. Further, the prepared samples were characterized by SEM, WAXD, FTIR, and mechanical measurements. The obtained results indicated that PP is much more sensitive to the method of sample preparation than PE, as well as that the initial preparation of samples plays a decisive role in the final properties of materials for polymeric medical devices.

Screen-printing process has been known for decades as an integral part of thick-film technology. Lately, it has been recognized as a possible means of pattern formation for stretchable electronic devices commonly used in fitness monitoring, epidermal and wearable healthcare. These devices are formed on thin flexible substrates in combination with nanocomposites based on polymeric binders and conductive fillers. The objective of this paper is to present challenges that screen-printing process for stretchable electronics is facing such as key process requirements and parameters, selection of flexible substrates, properties of conductive nanomaterial inks and strain management near rigid areas.

Screen-printing process has been known for decades as an integral part of thick-film technology. Lately, it has been recognized as a possible means of pattern formation for stretchable electronic devices commonly used in fitness monitoring, epidermal and wearable healthcare. These devices are formed on thin stretchable substrates in combination with nanocomposites based on polymeric binders and conductive fillers. The objective of this paper is to present challenges that screen-printing process for stretchable electronics is facing such as key process requirements and parameters, selection of stretchable substrates, properties of conductive nanomaterial inks and strain management near rigid areas.