Effects of plasma pretreatment on the adhesion fastness of polyurethane/polyester composite fabrics
The textile industry is a high energy consumption and high pollution industry,with an annual emission of over 8 billion tons.China has introduced a pollution permit system to use legal and other means to control pollution sources and improve the surrounding ecological environment.In the context of China's promotion of green,energy-saving,and environmentally-friendly measures,the current adhesives used in fabric processing in composite factories are mainly solvent based hot melt adhesives.During the operation,organic solvents are prone to volatilization,causing environmental pollution and human injury due to strong odors.And the water-based polyurethane hot melt adhesive has advantages such as good elasticity,high adhesion,and low VOC content,making it a new type of adhesive that adapts to environmental trends.Composite fabrics are mostly used to make warm winter clothing,with a soft and smooth feel.The softener is mostly water repellent amino silicone oil,which conforms to the principle of compatibility with the solvent based hot melt adhesive.The adhesion fastness can meet national standards.On the contrary,the water-based polyurethane hot melt adhesive has a low solubility in water-repellent amino silicone oil,limited diffusion,and a significant reduction in the amount of adhesive absorbed into the fabric,resulting in poor adhesion fastness.The bonding surface of the fabric was treated with plasma,and after etching,numerous concave holes were formed on the surface of the fabric,increasing the specific surface area and friction coefficient of the fabric.The resulting porosity resulted in an excellent bonding effect of the composite fabric;the introduction of hydrophilic groups such as carboxyl groups,ether bonds,and amide bonds increased the moisture absorption of the fabric,and the diffusion of waterborne polyurethane hot melt adhesive to the fabric was also correspondingly improved;the polyester fabric treated with plasma was prone to reacting with water-based polyurethane to form carbamate bonds,urea bonds,and ion bonds,forming strong cohesion and bonding force,thereby increasing the peel strength of the fabric composite.The bonding surface of the fabric was treated with plasma,and the peeling strength of the composite fabric was tested under different process parameters.The optimized plasma process was obtained as follows:a discharge voltage of 25 kV,an action time of 5.5 minutes,and an action distance of 2 mm.The results show that after plasma treatment,the friction factor,specific surface area,roughness,wettability,and capillary effect of the fabric increase,making it easier for the water-based polyurethane hot melt adhesive to adhere and accumulate on the surface of the fabric during transfer,increasing the peel strength between composite fabrics.According to the optimized process,the peel strength of the composite fabric in the warp direction was increased from 2.3 N to 18.3 N,and the peel strength in the weft direction was increased from 1.2 N to 12.6 N.After 30 washes,the composite fabric did not show any peeling or bulging,and the peeling strength still met national standards.Due to plasma etching,the breaking strength of the fabric in both warp and weft directions decreased.The breaking strength decreased slowly before the action time of 5-6 minutes,and decreased rapidly after 6 minutes.It is expected that in the future,practitioners can increase their research and development efforts on water-based polyurethane,develop water-based hot melt adhesives with stronger adhesion,simplify the fabric composite process,shorten reaction time,and achieve instant composite like solvent based hot melt adhesives,so as to improve the production efficiency.
万方数据
维普
