① Identification methods include touch, visual inspection, combustion, microscopy, dissolution, drug color development and infrared spectrum. In the actual appraisal, it is often necessary to use a variety of methods, comprehensive analysis and research to get the results.

② The general identification steps are as follows:

A.

Firstly, natural fibers and chemical fibers are distinguished by combustion method.

B.

If it is natural fiber, observe and identify various plant fibers and animal fibers through a microscope. If it is a chemical fiber, it should be distinguished one by one according to the difference of melting point, specific gravity, refractive index and solubility of the fiber.

C.

When distinguishing blended fibers from blended yarns, it is generally possible to confirm that there are several kinds of fibers through microscope observation, and then identify them one by one through appropriate methods.

D.

For dyed or finished fibers, dyeing and stripping or other appropriate pretreatment are generally needed to ensure the reliability of identification results.

Non-professional, general methods mainly rely on hand feeling and combustion method:

Acrylic: fluffy, furry.

Melting and burning near the flame, melting and burning in the flame, burning and splashing quickly after leaving the flame, with weak smell and hard round, irregular or beaded ashes.

Polyester: polyester

Good strength, good wrinkle resistance, low price, static electricity and no irritation to skin.

Near-flame droplet, bubbling in flame, continuous burning, light fragrance, hard round, black or light brown gray, and can be crushed.

Spandex: spandex

It is complicated, and with the different content of components, the characteristics of distinguishing differences are also subtle.

Determine the proportion of polyester and cotton according to ash content.

Nylon: polyamide

Good strength, better handle than polyester, high cost performance, underwear fabrics are mostly nylon.

Smell, small gray, light brown hard ball.

cotton

: cotton

C

Soft to the touch, natural fiber, good hygroscopicity and comfortable to wear.

It burns when it is close to the flame, and there is afterglow after burning. It smells like burning paper, and there is little, soft, black or dark gray ash.

The difference between polyester and acrylic acid

1, which is a synthetic fiber in chemical fiber;

2, high strength and good wear resistance; Widely used in clothing and industrial applications.

3, poor air permeability, uncomfortable wearing heat, easy to generate static electricity.

Difference:

1, the specific gravity is different. Polyester 1.38, nylon 1. 14.

2. Polyester fabric is not easy to wrinkle, and it is stiff, with good dimensional stability and shape retention. Nylon has poor shape retention, unlike polyester, which is stiff and easy to deform.

3. The melting point of polyester is 260℃ and the ironing temperature can reach 180℃. The heat resistance of nylon is not good enough, the ironing temperature should be controlled below 140℃, and the low temperature resistance is good.

4. Nylon has high strength, good elastic recovery, excellent wear resistance and better hygroscopicity and dyeability than polyester.

5. Polyester is resistant to sunlight, acid and alkali. Nylon is alkali-resistant and acid-resistant, and its light resistance is not good. After long-term sun exposure, its fiber strength will decrease and its color will turn yellow.

6, nylon woven feel smooth, high surface gloss. Clothing materials are mostly sportswear, swimsuits, fitness clothes and socks.

7. Polyester fiber is the largest synthetic fiber in the world. Polyester fabrics mainly include knitted shirts, work clothes, warp-knitted decorations, curtains and so on. Silk, wool, hemp and wadding are also widely used. Polyester short silk is often blended with cotton, wool, hemp and viscose fiber. Its fabric not only maintains the characteristics of fastness, wear resistance, stiffness and easy collection of polyester, but also has the characteristics of moisture absorption, warmth retention and less static electricity of natural fibers.