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Modifying plant fibers before their incorporation into the polymer matrix is a crucial factor that influences the characteristics of the resulting composites. This article reports on a study that investigated how modifying ground corn stalks impacted certain properties of a biodegradable polymer composite. The composite was made up of a mixture of polylactide and polycaprolactone in a ratio of 70:30, and the filler was modified using dopamine hydrochloride to create a thin polymer layer of polydopamine on the surface of the particles. The study evaluated the structural, mechanical, thermal, and thermomechanical properties of composites that contained 30%, 40%, or 50% of the filler by weight. Additionally, the tests to determine how well the composites would compost in an industrial setting were conducted. The results of the study showed that modifying the filler particles had a positive impact on most of the properties tested, including tensile strength, flexural strength, Young's modulus, storage modulus, and impact strength. Interestingly, despite concerns about the antibacterial properties of polydopamine, the composting tests revealed that the modification of the filler particles did not have any negative effects on the industrial composting process. [ABSTRACT FROM AUTHOR]

The analysis of LiDAR‐based digital elevation models revealed the existence of groups of longitudinal fractures in the ground in northern Poland at the limit of the ice sheet's extent during its last maximum. Our research on the closed elongated depressions (CEDs) of the Jedwabno test field (Szuć site, north‐east Poland) focuses on explaining their origins and their post‐glacial history. This region was covered by an ice sheet and glacitectonically active during the Vistulian, and at least some surface fractures are possible witnesses to this activity. Using geomorphological mapping, sedimentological and geophysical research, we assumed it was related that the origin of these features here is associated with groundwater migration at the end of the Vistulian glaciation or later when groundwater flow intensified due to a rapid climate warming that caused permafrost to melt. The thawing of permafrost caused to transition from continuous permafrost to discontinuous, which in turn created groundwater flow that was probably responsible for the development of the surface cracks (fractures). Radiocarbon, palaeobiological (pollen, Cladocera) and geochemical studies allowed for an estimation of the formation time of these unique surface cracks in the Older Dryas. Prevailing conditions were also reconstructed for the later dynamic changes of the end of the Late Vistulian glaciation and in the Late Holocene until the Subatlantic Period (Megalayan stage). The surface cracks with steep slopes, despite their small area, are extraordinary sedimentation traps that have, in a special way, retained an almost complete record of the environmental and climate changes of the Late Glacial. There are sedimentological gaps in the Holocene, especially after the Preboreal (old part of the Greenlandian Stage), caused by changes in water levels, aeolian processes and human activity. [ABSTRACT FROM AUTHOR]

Short flax fibers reinforced polycaprolactone (PCL) was crosslinked using electron irradiation and triallyl isocyanurate (TAIC) as coupling agent to improve mechanical properties. Effects of radiation dose and TAIC content on mechanical properties of PCL composites were studied using tensile, impact strength, and dynamic mechanical testing. Selected samples were examined using gel fraction analysis, thermogravimetry, and differential scanning calorimetry to define structural changes induced by electron irradiation at various content of TAIC. Biocomposites were manufactured by conventional extrusion and injection molding processing. Environmental stability of the biocomposites was evaluated for samples subjected to industrial composting. It was found that electron irradiation along with application of TAIC can improve both mechanical properties and environmental stability of flax fibers‐reinforced PCL. POLYM. COMPOS., 40:481–488, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Formation of dunes in the Płock Basin of the Vistula River valley in Central Poland is connected with the aeolian processes that occurred within the European Sand Belt during the Late Pleistocene. Changes in sedimentation conditions, from fluvial (unit G1), to fluvio-aeolian (unit G2) then to aeolian (unit G3), were respectively recorded in the fluvioglacial terrace sand dune profiles in the village of Goreń Duży (the Płock Basin, Central Poland). Both fluvial and aeolian processes occurred in the periglacial zone of the last glaciation, the northern limit of which is defined by the Last Glacial Maximum (LGM), being 18.4 ka in the Płock Basin. River and ice-marginal valley terrace sand sediments, in association with glacial deposits, could be the source material for the studied aeolian bedforms. The results of morphoscopic analysis of dunal sand quartz grains indicate that rapid deposition occurred more often than did long-term longrange grain transport. Grain transport genesis begins during the Older Dryas, which is confirmed by optically stimulated luminescence (OSL) dating performed for unit G2: 13.06±0.76 ka and 13.54±0.84 ka. During dune formation, dead-ice blocks remained intact in a subglacial channel until the Allerød, which suggests that aeolian processes continued after block melting, throughout the Younger Dryas. Successional aeolian processes have resulted in the extensive dune fields of the Płock Basin. [ABSTRACT FROM AUTHOR]

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The paper presents the effects of biodegradation of polylactide containing natural anti-aging compounds. Polymer containing 0.5; 5 and 10 wt % of coffee, cocoa or cinnamon extracts were subjected to industrial composting for 7, 14, 21 or 28 days. The effect of the composting process on polylactide properties was examined based on visual assessment, scanning electron microscopy, average molecular weight, differential scanning calorimetry, thermogravimetry, and tensile strength. The impact of the tested extracts on the effects of the composting process was compared with the impact of a commercially available anti-aging compound. It was found that the tested extracts in most cases did not adversely affect the effects of the composting process compared to pure polylactide, often resulting in intensification of biodegradation processes. As a result of the composting process, changes in the macro- and microscopic appearance of the samples and a decrease in molecular weight, phase transition temperatures, thermal resistance, and thermal strength were observed on a scale close to or greater than the reference anti-aging compound. [ABSTRACT FROM AUTHOR]