The Puncture and Water Resistance of Polyurethane- Impregnated Fabrics after UV Weathering

Abstract

Polyurethane is a polymer adaptable to different scientific and industrial requirements; nevertheless it is also extremely susceptible to UV radiation, which compromises the physical and mechanical functionality. In this framework, our study investigated the effect of waterborne polyurethane dispersion (WPUD) applied to a polyester (PET)-based fabric, through the impregnation method, on the puncturing and water resistance of the pristine material, before and after UV weathering. Results confirmed an increment of both features in the prepared fabrics, attributed to the PUR textile treatment; but a partially loss of the gained properties in the samples due to the UV weathering. In order to improve the efficiency of the impregnating dispersions, in protecting the durability of the treated materials, the addition of different UV light stabilizers, or/and of crosslinking agent into WPUD was also tested. From the experimental data, it can be concluded that formulations based on WPUD, containing both the crosslinker and UV organic absorber, have displayed an increment of their perforation and water resistance for the treated samples with respect to the starting textile, and contemporary have preserved the features against the UV light. Finally, microscopic and spectroscopic analyses have been performed as further characterization techniques of the samples surface.Polymers 2020, 12, 15 2 of 14 and petroleum depletion concerns, scientific research attention has been paid to study eco-friendly alternatives, i.e., waterborne polyurethane dispersions (WPUDs), with very low VOC emissions and with water as a low-cost, safe for health and the environment, and non-toxic solvent [7]. The aqueous polyurethane characteristics derive essentially from the chemical structure of urethane groups, by which multiple hydrogen bonds between adjacent polymer chains can take place. The chemical arrangement is constituted through hard segments that align in a dry polymer, and self-assemble into strongly hydrogen-bonded areas via flexible soft segments. The multiplicity of strong hydrogen bonds provides the properties commonly associated with a covalently bonded network [8].In the literature, different works have explored the possibility of developing green methods for the synthesis of WPUDs which can be applied as coatings, adhesives and finishing agents, useful for industrial production and application. The results have confirmed that WPUD coatings are endowed with excellent thermal stability, waterproofness and good mechanical properties, in terms of elongation at break and tensile strength [9][10][11][12].In general, the exposure of a polymer to UV radiation causes breakage of the chemical bonds in the material, a subsequent reduction of its molecular weight and a loss in its mechanical features ("photo-oxidative degradation") [13]. Since polyurethane coatings are also utilized for outdoor applications, high durability and weathering resistance may be required for the ambient exposure to ultraviolet (UV) radiation, water/humidity, and tempe...

Polyurethane Impregnation for Improving the Mechanical and the Water Resistance of Polypropylene-Based Textiles

“…Then, in presence of polyurethane (Figure 10b), a thin opaque layer seemed to be deposited homogeneously on fabric surface, making edges of filaments linked among themselves. These considerations were analogously confirmed in a previous work on polyester-based fabrics [5].…”

“…These may require exposure to tension or abrasion forces, contact with water, oils or chemicals that reduce the functionality and alter the durability over time. In order to improve the overall performance of common fabrics, the application of a polymer to the textile surface has been investigated [4,5]. The treatment of PP nonwoven textiles with water-based acrylic copolymer emulsions, has been examined.…”

Synthesis and Characterization of New Polycarbonate-Based Poly(thiourethane-urethane)s

“…Polyurethanes (PUs) are an important group of polymers that have a number of unique properties [ 1 , 2 , 3 , 4 ], which provides opportunities for their use in various industries, e.g., packaging, electronic, automotive, construction, building and medicine [ 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. The various applications of polyurethanes also include the modification of textiles in order to provide them with increased mechanical strength and water resistance [ 12 , 13 ]. Among polyurethane materials, we can distinguish foams, adhesives, varnishes, fibers, elastomers, etc.…”

Towards the Sustainability of the Plastic Industry through Biopolymers: Properties and Potential Applications to the Textiles World

“…Polymers 2022, 14, 692 2 of 27 However, bio-based materials, i.e., a broad class of organic constituents produced from renewable resources endowed with specific structural and functional characteristics such as biodegradability, composability, or biocompatibility, could offer a potential solution to replace the conventional plastics (primarily made from polyester (PET) [9,10], polyamide (PA), and polypropylene (PP) [11][12][13]) involved in fabric and yarn production [14]. Biopolymers can be used in the textile industry as the constituent base material for the production of filaments and yarns, or to replace harmful chemicals in pre-treatment and finishing operations by providing textile substates with various potential functionalities, such as antibacterial and flame-retardant activity, UV protection, electric conductivity, and hydrophobicity [15].…”