Study On The Influence Of Light And Wet Factors On The Thermal Protection Performance Of Multi-layer Fabric For Firefighter-clothing

As production factors increase,fire accidents occur frequently.Fire service is an important equipment to protect the life safety of firefighters.Its thermal protection performance directly affects the life and safety of firefighters.However,during storage and operation,fire protection clothing will inevitably be affected by external factors such as sunlight and moisture,which will cause changes in protective performance.Therefore,it is of great practical significance to study the thermal protection performance of fire protection multilateralism fabrics in light and humid environments.In this dissertation,four kinds of outer fabrics,two kinds of waterproof and breathable layer fabrics,two kinds of heat insulation layer fabrics,and one kind of comfort layer fabrics are selected,and eight kinds of fabric combinations are formed through orthogonal experiments.TPP value test was performed on each combination fabric,and the best TPP value was selected as the research object by using the range analysis.The selected fabric combinations are separately subjected to sunlight irradiation,moisture wetness single treatment,light and moisture wetting composite treatment,and the parameters such as warp density,latitudinal density,areal density of the outer shells,thickness and gas permeability;thermal conductivity of multilateralism fabrics in wet state were tested.The TPP value and surface area shrinkage of multi-layer fabrics under light-wet single factor and light-wet composite factors were tested.The effects of illumination time,outer shells wetting amount and comfort lining wetting amount on the thermal protection properties of fabrics were studied by grey correlation analysis.To the extent,the TOPSIS method was used to comprehensively evaluate the thermal protection properties of fabrics.Research indicates:Among the selected layers of fabric,the combination of aramid 1414+aramid non-woven PTFE film+aramid felt 100%Kevlar+flame retardant cotton has the highest TPP value,which is used as the photo-humidity treatment and research objects.Light mainly affects its thermal protection performance by changing the warp and weft density of the outer fabric,reducing the thickness,area density,and breath ability of the multilayer fabric;the moisture has no significant effect on the structural parameters of the fabric,but reduces the permeability of the multilayer barrier.In addition,the moisture in the outer layer and the comfort layer fabric changes the heat transfer process between the fabrics by changing the thermal conductivity,heat capacity,etc.of the multilayer fabric,there by affecting its thermal protection performance.Under a single environmental factor,the light reduces the TPP value of the multilayer fabric and causes the surface area shrinkage of the fabric to increase first and then decrease.The amount of wetting of the outer fabric increases the TPP value of the multilayer fabric and reduces its surface area shrinkage.The comfort layer can reduce the TPP value of the fabric when it is in a low wetting state of 15%.When the wetting amount is more than 15%,the thermal protection performance gradually increases;the surface area shrinkage decreases with the increase of the comfort layer wetting amount,but The overall is still larger than when the comfort layer is not wetted.After the outer layer of the fabric and the comfort layer are simultaneously wetted,the TPP value decreases first and then gradually increases.At this time,the surface area shrinkage of the fabric is mainly affected by the negative influence of the amount of wetting of the outer layer.Under the light-wet composite factor,the TPP value was the best when the illumination time was 30h and the wetting amount of the outer layer and the comfort layer reached saturation.The illumination time was 20h,and the wetting amount of the outer layer and the comfort layer were 60%and 50,respectively.At%,the fabric surface area shrinkage is minimal.The amount of outer layer wetting has the most significant effect on the TPP value and surface area shrinkage of the fabric.The influence of the comfort layer wetting amount on the TPP value is greater than the illumination time,but the effect on the surface area shrinkage of the fabric is less than the illumination time.The comprehensive evaluation results show that under the single factor of light and humidity,the moisture in the outer fabric has the most significant influence on the thermal protection performance;under the light-wet composite factor,the illumination time is 20h,the outer layer wetting amount is 60%,and the comfort layer is wetted.When the amount is 50%,the fabric has the best thermal protection performance.