Soft finishing is the most common in textile dyeing and finishing, and organosilicon softener is also the most used auxiliary in textile dyeing and printing. This paper analyzes and tests the organosilicon softener sold in the market and its application performance, which provides reference for the selection of printing and dyeing enterprises.
Author: Liu ruining, Guo Xiujuan and Hou Lishan of Hebei Ningfang group Finishing) refers to the processing process in which the textile is not only deformed in its structure, but also stiff and rough in its handle due to the wet heat treatment of various chemicals and mechanical tension during the dyeing and finishing process. Soft finishing is to make up for this defect and make the fabric feel soft. There are two methods of soft finishing: mechanical and chemical. Mechanical soft finishing mainly uses mechanical methods to knead and bend the fabric for many times under tension state, so as to reduce the rigidity of the fabric and restore the appropriate softness.
The commonly used mechanical softening method is that the fabric passes through a plurality of tension square bars on the calender, and then is led into the soft rolling point formed by two soft rollers of the calender for light rolling. When the fabric passes through the tension bar, it is buckled many times, and then flattened by the soft rolling point, so as to obtain a smooth and soft hand feeling. However, this finishing method is not washable, so it is generally inclined to use softener. Chemical method is to reduce the friction coefficient between fibers with the effect of softener, so as to obtain the softness effect. Chemical methods are commonly used, sometimes supplemented by mechanical methods. Generally, the fabric is soaked in softener solution for a certain time, then dehydrated and dried; sometimes softener can be used together with other finishing agents; some softeners can produce washable finishing effect after baking.
1、 Test purpose
According to the problems that may be encountered in the production process, the silicone softeners are analyzed and tested with reference to the silicone emulsion performance test items.
2、 Test materials
Methylene blue, concentrated sulfuric acid, sodium sulfate, sodium dodecyl secondary sulfonate, chloroform; acetic acid, sodium carbonate, magnesium chloride; electromagnetic temperature controlled agitator, constant temperature drying oven, etc.
3、 Chemical stability test
Test items and methods: refer to "silicone emulsion performance test items".
4、 Hydrophilicity and softness test
1. Test fabric
20 × 16 128 × 60 pure cotton yarn card / semi floating cloth.
2. Test process
One soaking and one rolling (pressure 0.12 MPa, solid content 17%, dosage 40 g / L) → drying (1.5 min).
See the following table for the test results.
Note: viscosity test, Shanghai precision, snb-4 type, 2 × rotor, rotating speed: 12rpm.
Note: water washing standard, softener dosage 2% (o.w.f), normal temperature, time 10min, drying temperature 110 ℃.
5、 Conclusion
1. In the marked area, the chemical resistance of the products is good; in the marked area, the softness and smoothness after washing are poor, specifically: jh-818 / jh-819 produced by manufacturer F, MFA produced by manufacturer g, T618 produced by manufacturer H.
2. T805 produced by manufacturer h, according to the above washing method, the softness and smoothness of the washed fabric are better than all softeners in this test, and its chemical resistance stability is also very good, so it has been sought after by the market since its launch, and has become the blueprint for research and development by many manufacturers. Through the test, 688b produced by manufacturer J is mixed with 834g in a certain proportion, Its hand feel is basically the same as that of using T805 alone.
3. C320 independently developed and produced by manufacturer C has the same chemical resistance as T805, and slightly worse hand softness and smoothness than T805 (about 15-20%); products equivalent to c320 are: 688b / 834g produced by manufacturer J, 6101 produced by manufacturer I, T816 / T819 produced by manufacturer h; products similar to c320 are: has produced by manufacturer L, 6303 produced by manufacturer I, and H produced by manufacturer H T868 produced. Based on the above experimental results, c320 has its own market competitive advantage as a water repellent softener.
4. The terpolymer silicone oil 688b produced by manufacturer J has good chemical resistance stability and can be used in polyester, cotton, knitting and tatting. Through the test, it can be used in the softness and smoothness of denim fabric. On the whole, this product deserves further attention.
5. Soft oil concentrate alm-90 / oa-400 produced by manufacturer K: ① it has good acid resistance, which is equivalent to ointment 222, and 602 independently researched and developed by manufacturer C has unstable acid resistance; ② at present, the tested soft oil concentrate is unstable in both alkali resistance and electrolyte resistance, and its volume expands to different degrees after being diluted with water. When it is added into cold water, its solubility and diffusion are not very good, and improper operation will cause quality The softness of oa-400 is better than alm-90.
6. As a softener in knitting bath, has produced by manufacturer L has good chemical resistance stability and general hydrophilicity, which is another expansion of application field after the improvement of synthesis technology of organosilicon softener.
7. Softeners are classified according to the type of ions, including anionic type, cationic type, amphoteric type and non-ionic type. Some softeners have long chain of hydrocarbon, and the finished products feel soft, smooth and full. Some softeners are organosilicon polymers. The finished products feel smooth. Sometimes the two are mixed and the finished product feels plump and smooth. Anionic softener is mainly used in cellulose fiber products. After treatment, the fabric has good water absorption and sewing performance, but the softness effect is worse than that of cationic treatment. Anionic softener is suitable for all kinds of fibers, and it has the best effect for acrylic products. The treated fabric is soft and smooth, but it will reduce the sun fastness of some dyes. Amphoteric softener can be used in a wide range of pH, but its softening effect is low. The non-ionic softener has good compatibility with other preparations and is used in the same bath treatment with resin.
8. There is no uniform test method for the softness of textiles, which is mainly evaluated by hand feeling.
Attachment: silicone emulsion performance test items
1、 For solid content detection, weigh 1g (accurate to 0.0001) of the sample in a weighing bottle, dry it in an oven at 105 ℃ for 4h, take it out, transfer it into a dryer, cool it to room temperature, and weigh the mass. Repeat the above drying for 1h, and weigh the mass after cooling.
2、 Identification of anionicity 1. Add 10ml of methylene blue reagent (weigh 0.03g of methylene blue, mix with 12g of concentrated sulfuric acid and 50g of anhydrous sodium sulfate, and dilute to 1L with distilled water) and 5ml of chloroform into the stopper tube. Gradually add 0.5% organosilicon sample diluent (organosilicon emulsion is made into 0.5% dilute solution), add a drop of agitation, the original upper and lower obviously stratified tone, gradually showing the same tone. The color of the chloroform layer in the lower layer is thickened and the water layer in the upper layer is almost colorless, indicating that the organosilicon softener is anionic.
2. Nonionic identification add 3ml kbil4 solution prepared in the test tube, dissolve a {1.7g bismuth nitrite [bino3 (OH) 2 · bio (OH)] in 20ml glacial acetic acid, dilute to 100ml with distilled water, B (dissolve 40gki in 100ml distilled water) solution and combine in 1000ml volumetric flask, add 200ml glacial acetic acid, dilute to the scale with distilled water, 3ml BaCl2 solution (dissolve 20gBaCl2. 2H2O into 100ML distilled water) and gradually add 4mL diluent of organosilicon sample (organosilicon emulsion is made up to 0.01% to 0.1 diluent), and orange red precipitates appear, indicating that the silicone softener is non-ionic. 3. To identify the cation, add 10ml of bromophenol blue reagent in the test tube (use 75ml of 0.2mol/l sodium acetate solution, 925ml of 0.2mol/l acetic acid and 20ml of 0.1% bromophenol blue (96% ethanol solution) to mix together, keep the pH value of 3.6-3.9), Gradually drops into the silicone sample diluent (the silicone emulsion is made up of 10% dilute solution, adjusting pH value is 7) drops, such as the solution is sky blue, indicating that silicone softener is cations.
Three, emulsion stability 1. acid resistance in the 150mL beaker called 3G silicone emulsion sample, and then add 97mL acetic acid solution (adjusted to pH 2~3), placed 4h after static, observe the stability of the emulsion in the cup, and record whether there is bleaching oil stratification. 2. alkali resistance in the 150mL beaker, 3G silicone sample emulsion was added, 97mL soda solution was added (pH value was 12~13), static 4H was placed, the stability of the emulsion in the cup was observed, and the bleaching oil and stratification were recorded. 3. electrolyte resistant (magnesium chloride) in the 150mL beaker, 3G silicone emulsion samples were added, 2%MgCl2 and 6H2O solution 97mL was placed in a static place, observed at 4H and 24h respectively, and the bleaching oil and stratification in the cup were recorded. 4. the fluorescent whitening agent VBU is called 3G silicone emulsion sample in the 150mL beaker, if the 0.3% fluorescent brightener VBU solution 97mL is placed in a static place. Observe once in 4H and 24h respectively, and record the phenomenon of floating oil and stratification in the cup. 5. In a 150ml beaker, weigh 6.6g of 45% 2D resin and 1.0g of MgCl2 · 6H2O, add Vbu (0.3g) into the beaker, dilute to 100ml with water and place it in a standing position, observe once in 4H and 24h respectively, record the phenomenon of oil bleaching and stratification in the beaker. 6. Heat resistance: prepare 200ml of 3% organosilicon working solution in a 250ml beaker, put it into a constant temperature oven with the temperature adjusted to 45 ℃ for 4h, observe the stability of the working solution in the beaker, and record whether there is oil bleaching, oil bloom and other phenomena.
4、 Oil content of silicon emulsion Weigh 14-16g (accurate to 0.0002g) of the sample into the beaker, add 30ml of isopropanol, stir slightly with a glass rod to make it demulsify, and layer still. After the layer is clear, carefully pour out the water and alcohol layer, add some acetone and stir slightly, immediately pour out the acetone layer, and then put the sample into a vacuum drying oven, gradually raise the temperature and reduce the pressure, reach (50 ± 2) ℃ within 20-40min, and the residual pressure is 26 After maintaining 66pa for 2h, take out the sample and put it in a desiccator to cool it to room temperature and weigh it. M1 - beaker mass; M2 - sample and beaker mass; m3 - extraction oil and beaker mass.
The difference between the measured values shall be no more than 0.5% for two parallel determinations, and the arithmetic mean value shall be taken as the measurement result.
Five, the test principle of the amount of hydrogen contained in emulsion (including hydrogen silicone): hydrogen is hydrolyzed by hydrogen containing organosilicon in alkaline solution. Test method: weigh 0.5g of sample in a conical flask, add 10ml of distilled water, connect with a small separating funnel (in which water dissolving solution x ml) and capillary. The other end of the capillary is passed into a large inverted separating funnel filled with water. When the piston of the small separation funnel is opened, the hydrolysate enters the conical flask from the small separation funnel. After adding, the stirring is started, and the hydrogen is discharged. After passing through the capillary, the hydrolysate enters the large separation funnel. After all the gases are discharged, read the ML number. The hydrogen content (ml / g) is calculated according to the formula: V1 - hydrogen collection amount; V2 - hydrolysate amount; m - sample mass. About the author: Liu ruining, light chemical engineering major, intermediate Engineer - end -