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This paper deals with the development and characteristics of the properties of a permeable water-resistant heat insulation panel based on recycled materials. The insulation panel consists of a thermal insulation core of recycled soft polyurethane foam and winter wheat husk, a layer of geopolymer that gives the entire sandwich composite strength and fire resistance, and a nanofibrous membrane that permits water vapor permeability, but not water in liquid form. The observed properties are the thermal conductivity coefficient, volumetric heat capacity, fire resistance, resistance to long-term exposure of a water column, and the tensile strength perpendicular to the plane of the board. The results showed that while the addition of husk to the thermal insulation core does not significantly impair its thermal insulation properties, the tensile strength perpendicular to the plane of these boards was impaired by the addition of husk. The geopolymer layer increased the fire resistance of the panel for up to 13 min, and the implementation of the nanofibrous membrane resulted in a water flow of 154 cm2 in the amount of 486 g of water per 24 h at a water column height of 0.8 m.

Nanofibre membranes and nanofibre products represent break-through technology in many fields of industry. They are used for air or liquid filtration, and their unique properties are suitable for many new health products or when manufacturing clothes etc. Their biggest advantage is their high porosity and fineness. On the other hand, the disadvantage of these membranes is the fact that it is not a homogenous material/foil, but a layer of fibres or rather several fibre layers (hereafter we will always use the term nanomembrane). This structure has a very negative impact on some of its properties i.e. strength, abrasion resistance, pressure resistance etc. This work introduces a 2-layer-laminate and 3-layer laminate where one of the layers is made of nanofibres with a view to their use in the manufacturing of clothes for sport and outdoor activities. The nanofibre membrane laminate must protect the wearer from weather conditions like rain and snow and, at the same time, enable transferring of liquid moisture from the wearer’s body to the outside environment. Using lamination, we can connect the fine nanofibre membrane to a resilient textile material (knitted, woven or non-woven). This stronger textile material protects the more fragile nanomembrane from the outside environment (abrasion, friction etc.) while not diminishing its good comfort properties, like being windproof, waterproof and having good steam-permeability. The result of this work is a laminate with a high level of steam permeability, with minimum air permeability and a water column higher than 5000 mm. The tests carried out proved that during repeated washing cycles no delamination occurred and hydrostatic resistance decreased by approximately 20%.

Nanofiber materials offer a wide range of use in various production fields, e.g., different types of filtration, or areas requiring high hydrostatic resistance. They are made from different polymers, some of which are more hydrophobic than others, for instance some types of polyurethanes and polyvinylidene fluoride. However, even these polyurethanes cannot guarantee a high hydrophobicity of the final nanofiber material. To increase this desired property, we have to use the so-called hydrophobic substances like fluorocarbon. The nanofiber layer has to be prepared so that its pores do not get blocked, which would worsen its filtration capability and air permeability. This is why a roll-to-roll low-vacuum plasma was used in our case for creating a fabric with nanofiber layer for the clothing industry. The result is a nanofiber material with a hydrostatic resistance higher than a 15,000 mm water column. Under suitable conditions, we can produce a nanofiber membrane for clothing with thermophysiological properties similar to those of membranes produced with different principles, e.g., nanoporous membranes. The nanofiber membrane provides us desirable properties such as stability during repeated washing.