Unfinished leather has high water vapour permeability and low waterproofness because of its natural porous structure. To modify the surface appearance and hide any defects, to improve physical properties, such as light and rub fastness, resistance to water, solvents, abrasion, etc., leather needs to be finished. In this study the influence of waterborne finishing agents on the waterproofness and breathability of the hydrophobic leather obtained using different retanning, waterproofing, neutralization and dispersing agents has been investigated. The leather was characterized using morphological analysis and permeability studies.

In this work the effects of different crystallographic modifications of calcium carbonate (CaCO₃) filler on the melt flow, mechanical properties, hydrolytic degradation, and shape memory behaviour of recycled low-temperature poly(e-caprolactone)-based polyurethane (rTPU) were evaluated. Composites were prepared by two-roll milling varying filler content from 2 wt % to 6 wt %. It was found that at temperature range from 20 °C to 50 °C CaCO₃ fillers do not change Young’s modulus, they decrease tensile stress and deformation of rTPU, but improve its mechanical properties at elevated temperatures (up to 65 °C). rTPU melt flow index increases due to chain scission during the recycling and filler mixing with mill. Therefore, destruction temperature of rTPU is 20 °C lower than that of TPU. The CaCO₃ does not change shape memory properties independently of filler type and transition from secondary shape to the primary shape at 70 °C temperature is completed within 17 s for both filled and unfilled rTPU. The investigation of hydrolytic degradation shows that CaCO₃ only slightly increases degradation rate of rTPU.

DOI: http://dx.doi.org/10.5755/j01.ms.18.3.2433

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