Compatibility of Sustainable Mater-Bi/poly(ε-caprolactone)/cellulose Biocomposites as a Function of Filler Modification

Despite their popularity and multiplicity of applications, wood–polymer composites (WPCs) still have to overcome particular issues related to their processing and properties. The main aspect is the compatibility with plant-based materials which affects the overall performance of the material. It can be enhanced by strengthening the interfacial adhesion resulting from physical and/or chemical interactions between the matrix and filler, which requires introducing a compatibilizer or a proper modification of one or both phases. Herein, the impact of cellulose filler modifications with varying contents (1–10 wt%) of hexamethylene diisocyanate (HDI) on the compatibility of Mater-Bi/poly(ε-caprolactone) (PCL)-based biocomposites was evaluated. An analysis of surface wettability revealed that the filler modification reduced the hydrophilicity gap between phases, suggesting compatibility enhancement. It was later confirmed via microscopic observation (scanning electron microscopy (SEM) and atomic force microscopy (AFM)), which pointed to the finer dispersion of modified particles and enhanced quality of the interface. The rheological analysis confirmed increased system homogeneity by the reduction in complex viscosity. In contrast, thermogravimetric analysis (TGA) indicated the efficient modification of filler and the presence of the chemical interactions at the interface by the shift of thermal decomposition onset and the changes in the degradation course.This work was supported by the National Science Centre (NCN, Poland) in the frame of SONATINA 2 project 2018/28/C/ST8/00187—Structure and properties of lignocellulosic fillers modified in situ during reactive extrusion. The study was partially co-funded under project with grants for education allocated by the Ministry of Science and Higher Education in Poland executed under the subject of No 0613/SBAD/4820

Czy tylko blaszane zegarki? Znaczenie współczesnych jarmarków-przykład Jarmarku Katarzyńskiego w Toruniu

The study aims at showing the multidimensional significance of fairs as a tourist attraction from the economic and social point of view on the example of the Jarmark Katarzyński which holds in the city of Toruń. It has been assumed that, despite the total loss of the traditional impact of fairs, in modern cities fairs can still significantly form the social and economic life. The impact is completely different from that observed in the past. However, the directions of the impact of fairs, formed in past centuries, are still visible in the modified form in the context of cultural tourism. The research has been based on the original data obtained from a survey

Rank and thematic scope of NASA’s resources available on YouTube videosharing website

The article presents the author study, the aim of which is to define the thematic scope of resources employed in research of NASA scientists and give them the appropriate rank. The value ranks were determined by the functions performed by various divisions, highlighting their importance from the point of view of the Internet user. As a result, this article presents the partition of a set of resources due to the leading topic of animation and describes the significance of the collection to the public in of scientific, economic, cultural and social context. The object of analysis were visualizations available on the official YouTube channel: NASA Goddard. The research was carried out on the basis of a subscription channel organization in the server, the articles posted on the website of NASA and the scientific publications of the team members. The first stage of this work was to see the English-language films, to make their translation and to identify the thematic groups, called the work levels. Elements forming interpreted resource were classified employing the deductive method, where the levels of higher (general) order were divided into lower order levels with a certain degree of detail

Inhibition of Polymer Photodegradation by Incorporation of Coffee Silverskin

Over the last years, the trend associated with the incorporation of materials from renewable resources into polymer technology is getting significantly more vital. Researchers are trying to transfer the properties of natural raw materials into the polymer world. Therefore, different natural materials are more often investigated as potential additives for polymers. Such an effect is noted for the coffee industry byproducts, such as coffee silverskin. Because of the relatively high contents of compounds showing antioxidant activity, such as caffeine, polyphenols, tannins, or melanoidins, this byproduct could be considered not only as a filler, but also as a potential modifier for polymer materials. Its antioxidant activity is comparable to commercially available antioxidants applied in polymer technology. Therefore, in the presented paper, we examined the influence of the coffee silverskin (from 1 to 20 wt %) on the thermal and mechanical performance of polyethylene-based composites. Moreover, materials were subjected to accelerated aging tests in the UV chamber, which revealed that coffee silverskin could inhibit the photodegradation of the polymer matrix. Therefore, this byproduct should be considered as an exciting alternative for the conventional lignocellulosic fillers, which could provide additional features to polymer composites

Morphology and the physical and thermal properties of thermoplastic polyurethane reinforced with thermally reduced graphene oxide

In this study, thermally reduced graphene oxide (TRG)-containing polyurethane nanocomposites were obtained by the extrusion method. The content of TRG incorporated into polyurethane elastomer systems equaled 0.5, 1.0, 2.0 and 3.0 wt%. The morphology, static and dynamic mechanical properties, and thermal stability of the modified materials were investigated. The application of TRG resulted in a visible increase in material stiffness as confirmed by the measurements of complex compression modulus (E′) and glass transition temperature (Tg). The Tg increased with increasing content of nanofiller in the thermoplastic system. The addition of thermally reduced graphene oxide had a slight effect on thermal stability of the obtained materials. The incorporation of 0.5, 1.0, 2.0 and 3.0 wt% of TRG into a system resulted in increased char residues compared to unmodified PU elastomer. Also, this study demonstrated that after exceeding a specific amount of TRG, the physicomechanical properties of modified materials start to deteriorate

Sustainable Strategy for Algae Biomass Waste Management via Development of Novel Bio-Based Thermoplastic Polyurethane Elastomers Composites

This work concerns the waste management method of algae biomass wastes (ABW). For this purpose, we prepared bio-based thermoplastic polyurethane elastomer (bio-TPU) composites. Algae biomass wastes are derived from algal oil extraction of Chlorella vulgaris and from biomass of Enteromorpha and Zostera marina. ABWs were used in the bio-TPUs composites as a filler in the quantity of 1, 5, 10, and 15 wt.%. The bio-based composites were prepared via the in situ method. Polymer matrix was synthesized from a bio-based polyester polyol, diisocyanate mixture (composed of partially bio-based and synthetic diisocyanates), and bio-based 1,3 propanediol. In this study, the chemical structure, morphology, thermal and mechanical properties of prepared composites were investigated. Based on the conducted research, it was determined that the type and the content of algae waste influence the properties of the bio-based polyurethane matrix. In general, the addition of algae biomass wastes led to obtain materials characterized by good mechanical properties and noticeable positive ecological impact by increasing the total amount of green components in prepared bio-TPU-based composites from 68.7% to 73.54%

Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction

This work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties such as impact and flexural strength, Young’s modulus, and hardness of the material. Moreover, the dynamic mechanical analysis (DMA) showed a significant increase in the material’s storage modulus and rigidity in a wide range of temperatures. The increase in glass transition of soft segments can be noticed due to the limitation of macromolecules mobility in the material. The thermogravimetric analysis showed a four step decomposition, with maximal degradation rate at TmaxII = 320–330 °C and TmaxIII = 395–405 °C, as well as a significant improvement of thermal stability. Analysis of the material structure using a scanning electron microscope showed the presence of material defects such as voids, fiber pull-outs, and agglomerates of both fibers

Mechanical, Thermal and Rheological Properties of Polyethylene-Based Composites Filled with Micrometric Aluminum Powder

Investigations related to polymer/metal composites are often limited to the analysis of the electrical and thermal conductivity of the materials. The presented study aims to analyze the impact of aluminum (Al) filler content (from 1 to 20 wt%) on the rarely investigated properties of composites based on the high-density polyethylene (HDPE) matrix. The crystalline structure, rheological (melt flow index and oscillatory rheometry), thermal (differential scanning calorimetry), as well as static (tensile tests, hardness, rebound resilience) and dynamic (dynamical mechanical analysis) mechanical properties of composites were investigated. The incorporation of 1 and 2 wt% of aluminum filler resulted in small enhancements of mechanical properties, while loadings of 5 and 10 wt% provided materials with a similar performance to neat HDPE. Such results were supported by the lack of disturbances in the rheological behavior of composites. The presented results indicate that a significant content of aluminum filler may be introduced into the HDPE matrix without additional pre-treatment and does not cause the deterioration of composites’ performance, which should be considered beneficial when engineering PE/metal composites

Static and Dynamic Mechanical Properties of 3D Printed ABS as a Function of Raster Angle

Due to the rapid growth of 3D printing popularity, including fused deposition modeling (FDM), as one of the most common technologies, the proper understanding of the process and influence of its parameters on resulting products is crucial for its development. One of the most crucial parameters of FDM printing is the raster angle and mutual arrangement of the following filament layers. Presented research work aims to evaluate different raster angles (45°, 55°, 55’°, 60° and 90°) on the static, as well as rarely investigated, dynamic mechanical properties of 3D printed acrylonitrile butadiene styrene (ABS) materials. Configuration named 55’° was based on the optimal winding angle in filament-wound pipes, which provides them exceptional mechanical performance and durability. Also in the case of 3D printed samples, it resulted in the best impact strength, comparing to other raster angles, despite relatively weaker tensile performance. Interestingly, all 3D printed samples showed surprisingly high values of impact strength considering their calculated brittleness, which provides new insights into understanding the mechanical performance of 3D printed structures. Simultaneously, it proves that, despite extensive research works related to FDM technology, there is still a lot of investigation required for a proper understanding of this process