Preparation Of UV-curable Polyurethane Film And Its Application In The Fabric Surface

Ultraviolet(UV) curing is an energy-efficient and environment-friendly technologywhich turns liquid system into solid system rapidly under the action of high-strengthultraviolet radiation, It has been rarely used in fabric finishing areas. Examples of UV curingtechnology in coatings, inks and other areas of a large number of applications provide a newchoice for textile coating finishing in the future.In this paper, the author explored a new wayin fabric finishing areas by using light-cured polyurethane acrylate coating for UV-curablefilm-forming experiments and applied it to the surface of the cotton fabric.In the present work, the preparation methods of polyurethane film based on UVlight-curing reaction were discussed, using the materials of polyurethane acrylate,tri-propylene glycoldiacrylate, Darocure184and ethyl acetate.The properties of the UV-curedfilm were analyzed, including wear resistance, water absorption and its solubility as well. Thestructure and performance of the film were also characterized by using FTIR and TGA. Thecharacteristics of surface morphology, contact angel and tensile strength, for the coated cottonfabrics based on the UV curing method were compared, respectively. In order to compare theapplication effect on two different segments of the urethane acrylate, the polyester andpolyether PUA was used separately as the light curing systems subject, to compare theperformance of two different segments in the cured PUA. Meanwhile, in order to increase thewater vapor permeability of UV light curing polyurethane film,the effect of UV curedmicroporous membrane performance was studied when PEG1000was used as porogen, watervapor permeability, water absorption, porosity and surface morphology of the UV cured filmwas analyzed.The results showed that:（1）UV cured film is stable below300℃, which is suitable to be used in the textilefabric coating finish with its good resistance to sunlight,wear resistance, low water absorptionand good resistance to volatile solvents.After the cotton fabric coating and a series ofperformance tests, the results show that:The use of UV curing technology for coating thefabric is a feasible,not only efficient, but also environmental compared to those traditionaltechniques. UV-cured composite cotton fabric is better than traditional cotton fabric inapparent preparation, breaking strength and water resistance, especially prominent in terms ofwater resistance.The contact angle of the treated cotton fabric can reach128.6o, waterprooffabric and breaking strength are better than untreated cotton fabric. IT can be used in thepreparation of a waterproof material. （2）After PUA coated cotton fabric, wrinkle properties, drape and wear properties ofcotton fabric are greatly improved.And a comparison of the two soft segments PUA coatedcotton fabric shows that the wrinkle recovery angle of polyether PUA coated fabrics is greater,drape coefficient is smaller, Its anti-pilling polyester series is consistent with PUA coatedpolyester fabric. Although the amount of wear is greater than the polyester-based PUAcoating, but the difference is small.（3）After the PEG was added to be used as the porogen in the photo-curablepolyurethane systems,Observed it under SEM, microporous in different size can be seen,Andwith the increase of the added amount,the amount of surface pores,intensity and aperture wasincreased.When the porogen is added to the content of20%, UV curable urethane membranesurface aperture12~20um, close to the diameter of droplets20um. After adding porogen,breathable performance UV curable polyurethane film, water absorption, porosity of acorresponding increase in the dosage20%when compared to the original film did not addPEG UV curing, moisture permeability increase of377%, a significant improvement inmoisture permeability. Meanwhile, coated cotton fabric permeability increases in multiplesof30times to achieve the original, breathable tremendous amount of improvement inresults.The foregoing analysis, when PEG dosage20%, both to ensure that no water dropletsthrough a UV-curable polyurethane membrane surface, but also to improve its water vaporpermeability, making this experiment UV-curable polyurethane film has a good waterproofbreathable performance.