多层织物系统综合热防护性能

研究了消防服用多层织物系统的综合热防护性能.将耐高温阻燃织物Nomex、Kermel和芳砜纶织物与PTFE、TPU和三维阻燃间隔织物组合,模拟消防服的层次构成,通过垂直燃烧实验测试分析了外层织物的阻燃性能,通过TPP(热辐射和热对流综合热防护性能)实验测试分析了多层织物系统的综合热防护性能.研究得出:热防护性最大的织物组合是芳砜纶、三维阻燃间隔织物和阻燃棉布;最适宜用于消防服的织物组合是NomexⅢ A、三维阻燃间隔织物和阻燃棉布;可将三维阻燃间隔织物用于消防服结构组成中,有助于减轻消防员的热负荷.     

消防避火服外层织物辐射热防护效能研究

通过对高硅氧玻璃纤维织物(A1)、高硅氧玻璃纤维织物(B1)、连续玄武岩纤维织物(XW)三类消防避火服外层织物材料进行比热容、X射线衍射图谱与热射线反射率等织物辐射热防护性能相关指标的测定,比较了三类消防避火服外层织物材料的防护性能,并从微观纱线分子架构等角度对造成三类材料辐射热防护性能差异的原因逐一进行了解释与分析。根据分析与计算结果,认为纤维内部微观结构与织物辐射热防护能力有着较为紧密的联系,纤维结晶度对织物热射线反射能力的影响显著。     

反热辐射层对消防织物系统热防护性能的影响

火场环境中,热辐射是造成消防员烧伤的主要原因之一,因此消防面料的反热辐射性能对保护消防员的生命安全至关重要。为了增加消防面料的反辐射效果,本文将铝箔作为反热辐射层置于消防服面料系统中的不同位置,通过测试加入了反热辐射层后系统的TPP(Thermal protective performance)值,以此探究其对消防面料的热反射效果。实验结果表明:增加反热辐射层后系统TPP值均有所提高,当反热辐射层位于外层和防水透气层之间时,TPP值为54.32,热防护效果最好;而将其放在外层之上直面火源时,TPP值为45.50,则防护效果最差。通过打孔来改善铝箔的通透性,以提高系统的透气性能,但铝箔的孔洞率越大,系统的热防护效果越差,当孔洞率由0个/cm2增大到37.42个/cm2时,TPP值由64.28降至51.84。     

热辐射对消防服热防护性能及耐久性的影响

为探讨低热辐射对消防服用织物热防护性能及物理机械性能的影响,选用两种常用消防服用外层织物,利用远红外石英灯管辐射仪,以不同的辐射强度(6.5kw/m2和9.7kw/m2)对织物分别进行5、10、20、30min的辐射,利用NI虚拟仪器记录辐射时织物表面温度,并测试其各项物理机械性能及TPP值变化。结果表明:当织物表面温度低于织物纤维玻璃化温度时,织物在半小时内能保持其68.9%～84.6%的撕破强力,且TPP值增大,即热防护性能变好;而当织物表面温度达到纤维玻璃化温度时,织物断裂强力及撕破强力随辐射时间增加显著下降,但其TPP值仍增大。     

玻璃纤维膨体纱织物热物理性能的实验研究

玻璃纤维是现代无机非金属材料中具有独特功能的材料,其来源丰富,价格便宜,具有强度高、耐高温、耐腐蚀等一系列优异性能,使其在热防护领域发挥不可比拟的作用.为提高玻璃纤维的热防护性能,首先采用自有知识产权的连续功能纤维束气流分散法,将玻璃纤维无捻粗纱制备成玻璃纤维膨体纱、玻璃纤维膨体花式纱及玻璃纤维膨体纱织物.其次,比较、分析了不同规格的玻璃纤维膨体纱织物的外观形态、力学性能、导热系数及热防护性能.研究表明:本实验制备的玻璃纤维膨体纱织物外观丰厚,且存在较多空隙,具备良好的蓬松性和热防护性能,其中,以膨体纱作为直接纬纱制备的织物热防护性能最好,手感最丰厚蓬松,与毡类制品最接近.     

环保型耐高温涂层织物的制备与性能研究

为制备受热熔融或分解后放出毒害气体低于致毒量的高性能热防护织物,通过在苯甲基有机硅树脂溶液中添加多种填料,利用改性的复合有机硅树脂溶液制备了玻璃纤维涂层织物.探讨了填料粒径及偶联剂等对涂层液存贮稳定性的影响,并对涂层织物的热防护性能和物理性能进行测试.结果表明:涂层后织物的烧蚀隔热性能显著提高,涂层织物为不燃材料;在不超过600℃受热30 min,其性能稳定;遇热释放的烟气中仅有少量的CO和NO_x,其含量远远低于制毒量;涂层后织物具有良好的强力、拒水、拒油及抗静电性能.该涂层织物在产业用和建筑领域将具有广阔的应用前景.     

玻璃纤维膨体纱保温材料的开发及性能探讨

首先,选用玻璃纤维无捻粗纱制备了玻璃纤维膨体纱、玻璃纤维膨体花式纱及玻璃纤维膨体纱织物。其次,研究了玻璃纤维无捻粗纱和膨体纱的化学结构,并观察了它们的形态结构。最后探讨了膨体纱织物的透气性、力学性能、固定树脂能力及热防护性能。结果表明:玻璃纤维膨体纱织物外观丰厚,且存在较多空隙,具备良好的蓬松性、透气性、固定树脂能力及热防护性能。     

涤纶织物纳米Fe3O4颗粒化学复合镀铜

采用化学镀技术,实现了涤纶织物纳米Fe3O4颗粒化学复合镀铜,借助SEM、EDX和TG对镀层表面形貌、成份以及织物热性能进行了研究,测试了化学镀铜织物的电磁波屏蔽、导电和耐磨性能.结果表明与普通镀铜织物相比,纳米Fe3O4复合镀铜织物的热起始分解温度没有明显变化;随着纳米Fe3O4添加量的增加,镀速先下降后上升,纳米Fe3O4复合镀铜织物的耐磨性能先增强后稍有所减弱;使用三聚磷酸钠作为分散剂时,镀层表面晶孢颗粒细小、分布均匀;当增重率接近时,纳米Fe3O4复合镀铜织物的电磁波屏蔽性能较普通镀铜织物为好.     

具有保温性能的电纺LA/PET纳米纤维复合织物的制备与表征（英文）

本文制备了电纺月桂酸(LA)/聚对苯二甲酸乙二醇酯(PET)纳米纤维/机织物的复合织物,并对其进行了表征。选用纯棉纱线、毛纱线、涤棉纱线、腈纶纱线和涤纶纱线分别作为经纬纱线,在实验室制备机织物小样,同时,通过静电纺丝法制备LA/PET纳米纤维,将LA包裹在PET基材之中。之后通过缝合的方式,将电纺LA/PET纳米纤维和机织物构造成三明治结构的复合织物。对纳米纤维的形貌和热性能进行了表征,并分别探究了LA/PET的质量比,机织物组织结构和机织物材料对复合织物保温性能的影响。结果表明:LA/PET纳米纤维呈圆柱形,具有光滑表面,LA和PET展现出良好的相容性,热焓值略低于理论值,但相变温度改变不大。复合织物的热保温性能测试表明,复合织物的保温性能都优于未加入相变材料的织物,同时展现出良好的热循环稳定性。     

具有保温性能的电纺LA/PET纳米纤维复合织物的制备与表征

本文制备了电纺月桂酸(LA)/聚对苯二甲酸乙二醇酯(PET)纳米纤维/机织物的复合织物,并对其进行了表征.选用纯棉纱线、毛纱线、涤棉纱线、腈纶纱线和涤纶纱线分别作为经纬纱线,在实验室制备机织物小样,同时,通过静电纺丝法制备LA/PET纳米纤维,将LA包裹在PET基材之中.之后通过缝合的方式,将电纺LA/PET纳米纤维和机织物构造成三明治结构的复合织物.对纳米纤维的形貌和热性能进行了表征,并分别探究了LA/PET的质量比,机织物组织结构和机织物材料对复合织物保温性能的影响.结果表明:LA/PET纳米纤维呈圆柱形,具有光滑表面,LA和PET展现出良好的相容性,热焓值略低于理论值,但相变温度改变不大.复合织物的热保温性能测试表明,复合织物的保温性能都优于未加入相变材料的织物,同时展现出良好的热循环稳定性.     

Thermal Response of Skin Underneath a Thermal Protective Garment During Post-fire Exposure

Once away from a heat source, the residual heat energy absorbed by thermal protective garments can continue to transfer and can injure human skin. Such a post-fire exposure period should not be neglected when investigating the thermal protective ability of thermal protective garments. In our paper, a heat transfer model of a microsystem consisting of a thermal protective garment, an air gap and multilayer human skin is established, and numerically solved via the Finite Element Method. Temperature distributions of the microsystem during fire exposure and post-fire exposure are extracted from the model, and the thermal behavior of skin underneath the thermal protective garment is elucidated. Two parameters [retardation time (Δt) and temperature maximum (T_max)] are proposed and employed to assess the thermal response of human skin during the post-fire exposure period. Furthermore, the effect of several factors (heat source intensity, thickness and thermophysical properties of the garment, and air gap thickness) on the two parameters and the thermal behavior of human skin are investigated and compared. This might be a significant reminder of self-protection for firefighters on duty, and informative or thermal protective garment design.     

Phase Change Materials for the Improvement of Heat Protection

The use of phase change materials (PCM) that absorb and store heat by an aggregate state change for applications in fire fighters' protective clothing was studied. PCM can help improve the heat protection of the clothing combination, and thus contribute to a reduction of the weight of the equipment and an improvement of the wearing comfort. It was found that PCM have a positive effect on heat protection, but the efficiency of the heat absorption depends on the location of the PCM layer and the incident heat intensity. Furthermore, as the PCM used was made of paraffin, its burning behavior has to be improved for a commercial use in fire fighters' protective clothing.     

The effect of silicon carbide additives on the stab resistance of shear thickening fluid treated fabrics

Applications of shear thickening fluids (STFs) with ballistic fabrics improve the protection performance of body protective systems. This article presents an innovative view of STF-impregnated ballistic fabrics by integrating silicon carbide (SiC) particles into targets. In this study, SiC particles were added into silica-based STFs, and Twaron fabrics were impregnated with this novel suspension. The effect of the SiC particles in the STFs was investigated with rheological testing. The results show that SiC particles are able to increase the viscosity profile of the suspension. In the stab testing, two types of impactors, such as spikes and knives, were dropped on the composite targets. According to the results, SiC particles enhance the protection performance of the STF-treated ballistic fabrics while keeping the flexibility.     

Cationization of cotton for industrial scale salt-free reactive dyeing of garments

Reactive dyeing of cotton garments involves two stages, namely exhaustion and fixation of dyes. The exhaustion stage in reactive dyeing requires high quantity of salt. After dyeing process, the highly saline coloured effluent is discharged and the treatment of this effluent at present is not economically viable and making industries look for other alternatives for usage of salt. Cationization of cotton is one of the effective alternatives to overcome the usage of the salt. The present work focuses on the exhaust method of cationization of garments at an industrial scale using 3-chloro-2-hydroxypropyl trimethylammonium chloride as a cationic agent. Two commercially popular reactive dyes namely Navy Blue and Green dyes were chosen for dyeing the garments at 10% shade. The results of dyeing were evaluated on the basis of colour strength, dyeing levelness and colour fastness. The uniformity of dye on the fabrics was evaluated based on dyeing levelness and was found to be good for cationized cotton dyed garments. The fastness properties of dyed fabrics to washing and light were good. The dye utilization in the cationized cotton dyed garments was twice as that of the conventionally dyed cotton garments. The environmental hazard posed by the highly saline coloured effluent could be easily mitigated by the salt-free reactive dyeing process.     

Thermal–mechanical modelling of laminates with fire protection coating

This paper presents a modelling approach to analyse the protection provided by passive and intumescent surface coatings on glass fibre reinforced laminate substrates exposed to fire. The modelling involves a multi-stage analytical approach: (i) thermal analysis of heat transfer from the fire through the surface insulation coating, which includes decomposition and expansion in the case of an intumescent material; (ii) thermal–chemical analysis of heat transfer through the fibreglass laminate substrate (beneath the fire protective coating), including decomposition of the polymer matrix; and (iii) thermal–mechanical analysis of softening and failure of the laminate under in-plane tension or compression loading. The modelling approach is validated using experimental temperature and strength data from fire structural tests performed on woven glass–vinyl ester laminates insulated with passive (ceramic fibre mat) or organic intumescent surface coatings.     

热阻塞效应在有机硅树脂-碳纤织物复合材料烧蚀防热中的作用

为评价热阻塞效应对有机硅树脂-碳纤织物复合材料防热的贡献,根据有机硅树脂的烧蚀防热机理建立热响应过程数学模型,预测了有机硅树脂-碳纤织物复合材料的背面温度以及有机硅树脂的热物性参数,重点分析了热阻塞效应对有机硅树脂-碳纤织物复合材料防热性能的影响。结果表明在400 kW/m2的热流烧蚀下,有机硅树脂-碳纤织物复合材料40 s前热阻塞效应大部分来自有机硅树脂分解产生的引射气体,40 s后则完全来自于炭燃烧产生的引射气体;阻塞因子在10 s时达到最小,此刻阻挡了121.6 kW/m2的热流进入有机硅树脂内,在整个烧蚀过程中热阻塞效应减少了4.1%的总热量进入有机硅树脂内;在热物性参数中,热阻塞效应对有机硅树脂密度影响最大,导热系数和比热容次之;与增加逸出气体质量流率相比,延长有机硅树脂逸出气体的时间更能显著提高热阻塞效应,达到更好的防热效果。      

Test method for evaluating fabric flammability and predicted skin burn injury in microgravity

To address fire safety concerns associated with the use of flammable fabrics during space travel, an apparatus was designed to be flown on low-gravity parabolic aircraft flights in order to assess the flammability of cotton and 50% cotton/50% polyester fabrics, and the resulting skin burn injury that would occur if these fabrics were to ignite. The apparatus, modelled after a standard fabric flammability test, was also used on the ground for experiments under earth’s gravity. Variables examined in the tests include gravity level, fabric type, air gap size, and orientation of the fabric. Flame spread rates, heat fluxes, and skin burn predictions determined from test results were compared under the two gravity levels. The orientation of the fabric had a large effect on flame spread rates, heat fluxes and predicted skin burn times for tests conducted under earth’s gravity. Flame spread rates and heat fluxes were highest when the fabric was held in the vertical orientation, which resulted in the lowest predicted times to produce skin burns. Flame spread rates and heat fluxes were considerably lower in microgravity than under earth’s gravity, which resulted in longer predicted times to produce skin burns.     

The effect of different passive fire protection systems on the fire reaction properties of GFRP pultruded profiles for civil construction

In order to study the viability of using GFRP pultruded profiles in floors of buildings, as structural elements, experimental investigations were carried out to analyse their behaviour when exposed to fire. In particular, the feasibility and efficacy of using different protective coatings/layers (an intumescent coating, a vermiculite/perlite cement based mortar and a calcium silicate board) to provide fire protection to GFRP pultruded profiles was investigated. Previous experiments showed that the above mentioned passive fire protection systems allow fulfilling fire resistance requirements for the envisaged application. This paper presents the results of the investigations concerning the fulfilment of the fire reaction requirements of those solutions. The experimental programme included dynamic mechanical analyses (DMA) and thermogravimetric and differential scanning calorimetry (TGA/DSC) experiments on both the GFRP and the fire protection materials. Subsequently, fire reaction tests were carried out on GFRP pultruded laminates, both unprotected and protected with the different fire protection systems, using a cone calorimeter. Results of these experiments allowed defining the field of application of each investigated solution, according to building code requirements.