HBP-HTC modified cotton fabric reactive dye salt-free dyeing
Abstract: Using EPTAC (glycidyl trimethyl ammonium chloride) and HBP-NH2 (amino-terminated hyperbranched compound), a self-made amino-terminated hyperbranched compound quaternary ammonium salt (HBP-HTC) modifier was used to cationically modify cotton fabrics. . The effects of factors such as the molar concentration of quaternary ammonium salt in HBP-HTC, HBP-HTC solution concentration, immersion time and temperature on the salt-free dyeing performance of reactive dyes on modified cotton fabrics were studied, and suitable modification process conditions were obtained:
EPTAC: HBP-NH2=2:1; soak in 4 g/LHBP-HTC solution at room temperature for 30 minutes, then wash. The test results show that modified cotton fabrics are dyed with reactive dyes without salt, and can obtain K/S values and dye fastnesses comparable to those of conventional dyeing of unmodified cotton fabrics.
Keywords: salt-free dyeing; reactive dyes; cationic modification; cotton fabrics
CLC number: TS193. 632 Document identification code: A Article number: 1000-4017(2019) 11-0005-03
0 Introduction
In the traditional dyeing process of reactive dyes for cotton fabrics, a large amount of salt needs to be added to improve the dye uptake rate and color fixation rate. The addition of salt will cause the deterioration of water quality and damage the ecological environment. Therefore, salt-free and low-salt dyeing with reactive dyes has become one of the hot issues that printing and dyeing workers are striving to solve. Among them, cationization of cotton fiber is a more effective way. That is, through chemical combination or physical adsorption, cationic compounds are fixed on the fiber to improve the dye exhaustion rate and color fixation rate, and reduce or even eliminate the use of inorganic salts.
Amino-terminated hyperbranched compound (HBP-NH2) is a highly branched, water-soluble polydisperse polymer containing abundant terminal amino and imine groups. This compound can combine with cotton fibers through van der Waals forces, hydrogen bonds and other forces, allowing the surface of cotton fabrics to absorb some amino-terminated overbranched compounds, thereby improving dyeing performance and achieving salt-free dyeing.
1 Test
1.1 Materials and reagents
The amino-terminated hyperbranched compound quaternary ammonium salt (HBP-HTC) is modified from glycidyl trimethylammonium chloride (EPTAC) Sex agent, obtained by grafting reaction with HBP-NH2. Its molecular structure is shown in Figure 1, and its preparation formula is shown in Table 1.
Pure cotton bleached cloth (120 g/m2, Huafang Group);
Reactive Orange 3R, Reactive Yellow 3-GL, Reactive Red 3BS , Active Blue GG (Taiwan Yongguang).
1.2 Instrument
LFY-304 Fabric Rubbing Color Fastness Tester (Shandong Textile Science Research Institute); SW-12A Washing Color Fastness Tester (Wuxi Textile Instrument Factory ); Ultrascan XE colorimeter (HunterLab Company, USA).
1.3 Test method
1. 3. 1 Cotton fabric HBP-HTC modification process
Place cotton fabric in 0~20 g/L HBP-HTC solution Medium, soak at 20~90℃ for 5~180 min, take out, wash and set aside.
1. 3. 2 Reactive dye dyeing process
Process prescription/(g/L)
Reactive dye/% (owf) 2. 0
NaCl 60 (NaCl is not added for salt-free dyeing)
Anhydrous Na2CO3 20
Liquor ratio 1∶50
Dyeing heating curve
After washing with water, add 3 g/L soap flakes, boil at 95°C for 5 minutes, and dry.
1. 3. 3 Color fastness test
The color fastness to rubbing is carried out according to GB/T 3920-1997 “Textiles Color Fastness Test – Color Fastness to Rubbing”; color fastness to washing The fastness is carried out according to GB/T 3921. 3-1997 “Textiles Color Fastness Test Color Fastness to Washing: Test 3”.
1. 3. 4 Determination of K/S value
Determine the K/S value of the sample on the Ultrascan XE colorimeter, using a 10° field of view, D65 light source, and the sample Fold four layers.
2 Results and Discussion
2. 1 Optimization of HBP-HTC modification process of cotton fabric
2. 1. 1 Effect of modifier ratio on K/S value Impact
Increasing the feed ratio of EPTAC to HBP-NH2 can increase the grafting rate of quaternary ammonium salt branch chains in the molecular structure of HBP-HTC, see Table 1. Cotton fabrics were treated with 4 g/LHBP-NH2 and HBP-HTC with different feeding ratios at room temperature for 30 min respectively. After washing, they were dyed with 2% reactive yellow 3-GL without salt. The color yield was tested. The results are shown in Figure 2.
From Figure 2, as the concentration of quaternary ammonium salt groups increases, the K/S value of reactive dye dyeing of HBP-HTC modified cotton fabric increases significantly. ���As the quaternary ammonium salt content in HBP-HTC increases, the positive charge on HBP-HTC increases and is easily adsorbed by the negatively charged cotton fiber surface. In addition, the molecular weight of HBP-HTC increases, the bonding force with fibers is enhanced, and the modification effect is good, which is beneficial to improving the salt-free dyeing performance of cotton fabrics. When the above feed ratio EPTAC:HBP-NH2=2:1, the amino groups in the HBP-NH2 molecules have been basically grafted completely, so the feed ratio is selected as 2:1.
2. 1. 2 Effect of HBP-HTC concentration on the dyeing properties of cotton fabrics
Cotton fabrics were impregnated with HBP-HTC at different concentrations. Other process conditions were the same as above. The results are shown in Figure 3. Show.
As can be seen from Figure 3, the dyeing performance of cotton fabrics is significantly improved after being modified by HBP-HTC cations. Since the surface of HBP-HTC has extremely abundant quaternary ammonium salt groups, cationic modification of cotton fabrics can be achieved with a lower concentration of HBP-HTC solution. When the concentration of HBP-HTC is high, HBP-HTC with lower adsorption fastness will fall off during the dyeing process, causing part of the dye in the dye solution to precipitate, resulting in a decrease in the K/S value of the fabric after dyeing. Therefore, the HBP-HTC concentration selected for this experiment was 4 g/L.
2. 1. 3 Effect of immersion temperature on salt-free dyeing of modified cotton fabrics
Place cotton fabrics in 4 g/L HBP-HTC solution at 20 and 60 Dip at 90°C for 30 minutes, wash with water and then dye, and test the dyeing performance. The results are shown in Table 2.
AAE4T45UY75T
Disclaimer:
Disclaimer: Some of the texts, pictures, audios, and videos of some articles published on this site are from the Internet and do not represent the views of this site. The copyrights belong to the original authors. If you find that the information reproduced on this website infringes upon your rights, please contact us and we will change or delete it as soon as possible.
AA
