Textile Antifouling Principle And Water Proofing, Antifouling And Oil Detection

Antifouling is to prevent textiles from being stained and easy to decontamination. It is easy to remove textiles after being stained, and is not easy to be washed in the washing process.

sewage

　　 The common pollution in life is divided into solid pollution (such as dust), liquid pollution (such as oil) and solid or liquid mixed pollution (such as motor oil and soot). The contamination of solid waste to fabric is mechanical adhesion to fiber. The contamination of liquid to fabric is the wetting, penetration or adhesion of liquid to fabric. It is adsorbed by intermolecular van Edward or hydrogen bond, mainly adsorbed by mechanical force and van Edward force. It is adhered to fabric by mechanical deposition, surface contact friction or electrostatic attraction. In general, the dirt on the fabric is mostly mixed pollution. Liquid contamination is a carrier or adhesive for solid contaminant, which makes it difficult to remove stains.

01

antifouling

　　 Antifouling is mainly to prevent liquid from wetting and wetting the fabric. The spreading of liquid on the fabric depends on the surface tension of the liquid and the critical surface tension of the fabric. When the surface tension of the liquid is higher than the critical surface tension of the fabric, the liquid can not spread on the surface of the fabric. Fabric antifouling can be achieved through water repellent and oil repellent finishing. Water repellent and oil repellent finishing will reduce the surface tension of the fabric to the surface tension of the oily dirt, so that the fabric will not be wetted by water and oily dirt, so as to achieve the purpose of antifouling.

02

decontamination

　　 The cleaning process consists of three steps.

1. The diffusion of water and detergent to the oil pollution fiber interface;

2, with the help of the shrinkage mechanism, the oil and fiber will be separated.

3, through mechanical action, the oil is removed into the water. For hydrophilic fibers, water can diffuse through the fiber to the oily fiber interface. For hydrophobic fibers, hydrophilic groups or hydrophilic finishing agents should be introduced to improve the fabric's hydrophilicity and shorten the initial stage of cleaning.

The easy decontamination finishing agent contains hydrophilic groups, and acts on the fabric after the hydrophilic segments are aligned on the fabric surface, so that the fabric is hydrophilic, and the water and detergent are more easily spread to the oiliness fiber interface. When the interface and the fiber surface are hydrated, the oiliness fiber interface is replaced by the water fiber interface and the water stain interface, thereby separating the oily dirt from the fiber.

Easy decontamination is to make fabrics hydrophilic, antifouling finishing is to reduce the fabric's surface energy, if the fabric has antifouling and decontamination, it is necessary to make the fabric hydrophilic in the liquid phase, and the air has very low surface energy. The three anti fouling finishing agents contain very low surface energy fluorocarbon segments and hydrophilic polyoxyethylene segments. When dry, polyoxyethylene segments are spiral, fluorocarbon segments are aligned on the fiber surface, showing water repellent and oil repellent properties. When wet, polyoxyethylene segments are aligned on the fiber surface, showing hydrophilic properties, thereby achieving antifouling and easy decontamination.

Standard for performance testing

The textile three proofing test mainly examines the ability of textiles to resist water, stain or resist oil droplets and dirt under certain conditions. A common oil repellency test is also one of the tests. The main criteria for testing textiles contamination are shown in Table 1.

　　 Waterproofing property

Referring to AATCC 22, the dynamic waterproof property of fabrics is determined by the test and evaluation of water repellency of textiles. The standard method of GB/T 4745 and ISO 4920 is basically the same as that of AATCC 22, and the fabric samples treated by waterproof and oil proofing are fixed on the metal ring of 150 mm diameter and placed on the fixed shelf with a tilt angle of 45 degrees. Pour 250 mL of water from the glass funnel above the sample to ensure that the natural spray is finished within 25-30 s. Remove the retaining ring and gently tap the fabric face down. Observe the wetting of the sample surface and evaluate its waterproof value. The spray device is shown in Table 2 below.

　　 Oil repellency

According to AATCC 118, GB/T 19977 and ISO 14419 are basically consistent with each other. "Oil expulsion: hydrocarbon resistance test" is used to determine the oil resistance of fabrics. Eight kinds of homologues, which are gradually decreasing in surface tension, were used as the standard solution. The test liquid of different grades was dripped on the surface of the finished fabric, and the wetting condition of the fabric after 30s was observed. If the final test solution does not moisten the fabric, the grade is the oil proof grade of the fabric tested. The 1 is the worst and the 8 is the best. The standard oil for testing oil resistance and its surface tension are shown below.

　　 Antifouling property

The standard of textile antifouling is usually referenced. The standard of stain resistance test method is GB/T 30159.1-2013 "testing and evaluation of textile antifouling properties: the first part: stain resistance", which is divided into liquid contamination method and solid contamination method. The basic principle of liquid contamination method is to add the prescribed liquid to the surface of the horizontal sample, observe the wetting, wicking and contact angles of the droplets on the surface of the sample, and assess the contamination level of the liquid dirt.

In order to select the first grade oil or soy sauce as a filth, two pieces of samples were selected. The samples were placed on 2 layers of filter paper and 0.05mL dirt was distributed in 3 parts of the sample. After 30 seconds, each droplet was observed at 45 degrees and rated.

The solid contamination method is to fix the sample in the test tube containing the specified solid waste, and turn the test tube to make the specimen fully contacted with the dirt. Compare the stain difference between the stained and non stained parts by using the gray card to evaluate the contamination degree of the solid stain. The test process is a mixture of dust and high pigment carbon black as a filth. Two pieces of sample are taken as the sample. The sample is placed on the fixing piece of the sample flat and fixed on the cylinder body. Then the contaminant is placed in the bottom of the cylinder. The test tube is put into the protective bag and put into the roll box, rolling 200 times, the sample is taken out, and the blower is blown to the dirt rating of the sample.

Soil Release

Textiles are easy to decontamination test is to put oil droplets or different stains on the fabric, and then wash the water under certain conditions, to determine the residual status of stains. The main criteria for easy decontamination of textiles are shown in Table 3.

　　 AATCC 130 easy decontamination test method

The test is mainly to measure the ability of fabric washing after washing. During the test, two samples of 38 * 38cm size were lowered to 4 hours after the temperature was 21 + 1 degrees, and the relative humidity was 65 + 2%. They were placed on a single layer of AATCC absorbent paper. The drops were dripped with 5 drops (about 0.2ml) of corn oil on the surface of the sample. The oil spots were covered with 3 x 3inch (7.6 * 7.6cm) cellophane. Then the weight of the 5, 0.1lb (5 + 0.045kg) weight was placed on the cellophane to place the 7.6 + 5S, then the heavy hammer was removed and the glassware was discarded. It should be noted that the samples treated with oil can not contact each other to transfer stains.

The sample is placed in the washing machine within 20 + 5min after the fouling. The washing material is selected according to the sample material and suitable for washing temperature. When washing, use a high water level, add 100 + 1g detergent to the washing machine, add the washing cloth to make the total load 4 + 0.15lb. The maximum number of samples per washing machine is 30. Set the washing machine in Normal file and run the 12min test time. Remove all washing cloth and cloth into the dryer. Set the dryer to Normal, set 45min or dry.

Immediately after drying, remove the sample cloth and put it flat to prevent wrinkle. Then within 4 hours, the sample will be compared with the rating card (a AATCC decontamination rating reference card shown in Figure 1). Each fabric is evaluated two times, and the average value of the four results is taken as the final result. The results of the report need to indicate what kind of rating card, water washing procedure and type of oil used, and also indicate the hardness of water, the type of washing cloth, the type of detergent and the washing machine and dryer used. The results range from 1 to 5. The higher the series, the smaller the residual oil remains, that is, the better the detergency; the smaller the series, the more residual oil remains, that is, the detergency is poor.