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Fibrous materials are often used in the manufacturing of fire protection devices such as fire curtains. Their optimization and improved performance is still a topic of interest. The present work aims to develop and test a new combination of fibers arranged in various 2D and 3D patterns with coatings. For this purpose, basalt fibers were added into a glass fiber fabric, and wires of a shape memory material (SMM) were inserted into the fabric to create air pockets induced by temperature. In fire curtains, the base structure is a 2D basket pattern, and all combinations were tested with and without a waterborne polyurethane (WPU) coating with inorganic materials. Three different tests were selected to characterize the thermal behavior: fire resistance, ignitability, and smoke production. Fiberglass proved to be the best material to provide thermal resistance in fire curtains, with the outer surface temperature of the fabric below 650 °C at the end of the tests. The SMM wires provided good protection during the initial stages of the test, but a combination of excessive deformation and reduced strength of the fabric resulted in a sudden failure of the structure. Basalt fibers contribute to a reduction of smoke production. It was observed an improvement of up to 10% in the thermal capacity between 1MIX2 (glass fibers fabric with coating, MIX2) and the best commercial curtain evaluated, Commercial3 (glass and steel fibers fabric with coating).

The protection of human life and goods assumes a growing concern in all forms of activities. The fire and smoke curtains act as a physical barrier to prevent the fire from spreading between spaces as well as to staunch the smoke and heat transfer to adjacent areas, while causing minimal interference. Usually, curtains are based on fiber structures that can be coated to enhance their protective capabilities. Also, the fiber structure can be developed into a complex pattern of 2D and 3D threads, with single or multiple materials that can be tailored to optimize its behavior. The thermal and fire protection depends on the fibers, fabric pattern and coatings. The present paper reports the development of novel coated structures of fibers used for fire protection curtains. Basalt and glass fibers are used as yarn materials. Following the certification standards the samples were assessed for their thermal resistance by measuring the temperature differential they provide while their integrity is evaluated. The sample is placed under stress in an attempt to mimic its own weight effect when in service. The temperature is monitored using thermocouples which are placed at both sides of the fabric and the integrity parameter is assessed through the occurrence of fabric rupture and smoke and/or odor release motivated by its deterioration. Regarding the uncoated samples, the one composed of glass-fiber in both directions presents the best thermal performance. The addition of an alumina coating significantly improves the performance of all samples. However, while a thinner (0.05 μm) alumina layer provides better results for the sample with glass-fiber in both warp and weft directions, the behavior of samples composed of glass-fiber and basalt is superior when a thicker (0.3 μm) alumina layer is used. In both cases, an alumina coating application results in an increase of the gradient temperature (between curtain inside/outside temperatures) of about 38.0% (310.0 °C vs. 427.0 °C for the first and 386.0 °C vs. 526.0 °C for the latter.

No abstract

The protection of human life and goods assumes a growing concern in all forms of activities. The fire and smoke curtains have as main role to act as a physical barrier to prevent the fire from spreading between spaces as well as to staunch the smoke and heat transfer to adjacent areas. They can also be easily operated (opening and closing) causing a minimal interference with the flow of materials and humans within confines spaces, such as warehouses and industries, while providing adequate protection. Thus, there are a set of characteristics that these products must exhibit high fire protection, thermal resistance and gas impermeability. The classification of the heat resistance, described in the European Standard BS EN 1634-1: Fire resistance and smoke control tests for door, shutter and, openable window assemblies and elements of building hardware — fire resistance tests for doors, shutters and openable windows, is the procedure that allows determining the response of a product in contributing by its decomposition to a fire to which it is exposed, being according to three criteria: (i) integrity, (ii) insulation and (iii) radiation. Usually curtains are based on fiber-based structures which can be coated to enhance their protective capabilities. In addition, the fibrous structure can be tailored to optimize its behaviour using 2D and 3D complex architectures, with single or multiple materials. The performance assessment of the curtains regarding the aforementioned parameters is performed resorting to several experimental procedures that are detailed in the specific standards. The present paper reports the development of novel fibrous structures used for heat protection curtains. They are based on the various combinations of hybrid structures combining 2 or 3 different yarn materials. The tests are carried out in a purpose built oven that induces a steep temperature rate (approximately 600 °C in 5 min) on one side of the sample followed by a slower rate up to 950 °C in 60 min. The sample is placed under stress during the test in order to mimic that caused by its own weight. Thermocouples monitor the temperature on both sides of the sample and its integrity is assessed by both the occurrence of fabric rupture and smoke release due to ignition. Both the fabric integrity and the temperature on the back side of the sample are an indicator of its performance which follows the European Standard BS EN 13501-2: Fire classification of construction products and building elements. Classification using data from fire resistance tests, excluding ventilation services. From the results one can conclude that hybrid structures, including either basalt and glass fibers, are the most suitable.