**2. UV irradiation and its application in textile industry**

One of the effective and economical methods of surface modification for both natural and synthetic polymers is UV irradiation. Excitation and dissociation of the polymeric molecules take place during exposing the surface to the UV treatment, which is known as a photosensi‐ tized oxidation process.

The color depth of the polylactide (PLA) and polyethylene terephthalate (PET) fabrics has been increased by the UV irradiation. This increase in the depth of dyeing is believed to be due to the surface roughening of the fabrics produced by the UV [2].

According to previous research work which has been done, the prepared thin film polyamide nanofiltration membranes were modified by acrylic acid (AA) and UV irradiation. The effect of UV-irradiation time and addition of AA on the performance and morphology of nanofil‐ tration membranes were investigated. The obtained membranes illustrate the ability for rejection of Na2SO4 and significant properties for separation of divalent ions from monovalent ions [3].

In recent years, many methods have been reported for modifying PET fabric to be hydrophilic. Different types of chemical auxiliaries can be used for this purpose. However, the hydrophi‐ licity of the treated PET surface is not durable because the coated hydrophilic material easily dissolves during repeated washes. Photo-chemical reactions and photophysical processes are gaining attention as techniques for modifying the surface of PET fabrics [4].

UV irradiation and treatment with nano-TiO2, H2O2, and NaOH increased the hydrophilicity of PET fabric, with an irradiation time of 30 min making the fabric nearly wettable and an irradiation time of 40 min making the fabric superhydrophilic. The greatest and most durable wettability results were obtained after 40 min of UV irradiation combined with 30 g/L nano-TiO2, 50 g/L H2O2, and 30 g/L NaOH treatment. The excellent mechanical and physical properties of PET fabric were retained after modification, although the breaking strength and elongation were slightly reduced. The induced hydrophilicity of the PET fabric can be considered permanent because the surface of the PET fabric was chemically modified with the introduction of hydrophilic groups [4].

In the other research, a new technique has been presented to graft sulfonic groups at the surface of PET fabric, which is based on UVC treatment with SO3 gaseous molecule. These modifica‐ tions improved the hydrophilic character of PET fabric surface and consequently its dying ability. The Schematic of system is shown in **Figure 1**. The air flow containing fuming SO molecules is injected into the vessel between which is composed of an UVC lamp and the fabric to be treated. The UVC lamp emits intense and nearly monochromatic light (254 nm). In fact, the UVC lamp emits 512 kJ mol−1 per photon, which allows the PET fibers functionalization without damaging their bulk properties. Sulfonic (SOH) groups can be introduced into aromatic compounds through an electrophilic substitution reaction. Such a reaction is referred as sulfonation [5].

**Figure 1.** UVC treatment device [5].

Alternatively, radiation technology involving low energy use, no chemicals, ease to handling, and high treatment speed can modify the surface of textiles and improve dye uptake, printing,

In this chapter the effect of ultraviolet (UV), gamma, plasma, laser, microwave, electron beam, ion beam, ultrasonic on surface, chemical, and physical and mechanical properties of textile

One of the effective and economical methods of surface modification for both natural and synthetic polymers is UV irradiation. Excitation and dissociation of the polymeric molecules take place during exposing the surface to the UV treatment, which is known as a photosensi‐

The color depth of the polylactide (PLA) and polyethylene terephthalate (PET) fabrics has been increased by the UV irradiation. This increase in the depth of dyeing is believed to be due to

According to previous research work which has been done, the prepared thin film polyamide nanofiltration membranes were modified by acrylic acid (AA) and UV irradiation. The effect of UV-irradiation time and addition of AA on the performance and morphology of nanofil‐ tration membranes were investigated. The obtained membranes illustrate the ability for rejection of Na2SO4 and significant properties for separation of divalent ions from monovalent

In recent years, many methods have been reported for modifying PET fabric to be hydrophilic. Different types of chemical auxiliaries can be used for this purpose. However, the hydrophi‐ licity of the treated PET surface is not durable because the coated hydrophilic material easily dissolves during repeated washes. Photo-chemical reactions and photophysical processes are

UV irradiation and treatment with nano-TiO2, H2O2, and NaOH increased the hydrophilicity of PET fabric, with an irradiation time of 30 min making the fabric nearly wettable and an irradiation time of 40 min making the fabric superhydrophilic. The greatest and most durable wettability results were obtained after 40 min of UV irradiation combined with 30 g/L nano-TiO2, 50 g/L H2O2, and 30 g/L NaOH treatment. The excellent mechanical and physical properties of PET fabric were retained after modification, although the breaking strength and elongation were slightly reduced. The induced hydrophilicity of the PET fabric can be considered permanent because the surface of the PET fabric was chemically modified with the

In the other research, a new technique has been presented to graft sulfonic groups at the surface of PET fabric, which is based on UVC treatment with SO3 gaseous molecule. These modifica‐ tions improved the hydrophilic character of PET fabric surface and consequently its dying

gaining attention as techniques for modifying the surface of PET fabrics [4].

fastness properties, adhesion of coatings, and adsorption of used chemicals.

**2. UV irradiation and its application in textile industry**

the surface roughening of the fabrics produced by the UV [2].

materials is fully discussed.

310 Radiation Effects in Materials

tized oxidation process.

introduction of hydrophilic groups [4].

ions [3].

The results reported in the other research demonstrate that the UVC (254 nm) irradiation method under a stream of gaseous Cl has the potential to graft PET textile fabrics. This technique has many advantages, such as easy handling, and it is a cheap, solvent-free contin‐ uous process without changing the bulk properties. The medication involves only a few nanometres of the surface. Several analytical techniques have confirmed that surface chlori‐ nation has occurred. Scanning Electron Microscope (SEM) analyses showed that the chlorina‐ tion only occurred at the surface of the fibers without changing the bulk of fibers. The Differential scanning calorimetry (DSC) thermograms indicated that the thermal characteris‐ tics of the PET fabrics were maintained. X-ray photoelectron spectroscopy (XPS) also showed the presence of Cl atoms in the upper molecular layers of the surface. The affinity of modified fabrics to cationic dyes is more than untreated samples [6].

For a long time, the textile industry has been searching for a rapid way to modify textile polymer surfaces. Obtaining good bonding between two dissimilar materials is critical for several aspects in textile finishes processing. Adhesion between PET and Tuftane Thermo‐ plastic Polyurethane (TPU) Film was improved by grafting NCO groups onto the PET surface using UV irradiation process by Dong Liu and his coworkers [7].
