Method for quick lossless distinguishing of polyamide product

Abstract

The invention relates to a method for the quick lossless distinguishing of a polyamide product. The method comprises the following steps: determining an analysis part of the product through a scanningelectron microscope; carrying out the element analysis through an EDS (Energy Disperse Spectroscopy), and calculating the atomic percent of carbon elements in the product; determining whether the measured polyamide product is a polyamide product of a first type or a polyamide product of a second type according to the size of the content of the carbon elements. The polyamide product of the first type is a product which is formed by the polymerization of amide monomers, wherein the number of carbon elements in the biggest monomer of the product is greater than ten. The polyamide product of thesecond type is a product which is formed by the polymerization of amide monomers, wherein the number of carbon elements in the biggest monomer of the product is less than seven. The method cannot cause the loss of a sample when the method is used for the analysis of the polyamide product, and enables the sample to be maintained. The method can quickly discriminate the polyamide products, and is simple in operation. The method also enables the fiber discriminating methods to be abundant, and provides a new thinking for the fiber discrimination.

Description

technical field

[0001] The invention relates to a method for identifying physical evidence such as fibers, in particular to a method for quickly and non-destructively distinguishing polyamide products. Background technique

[0002] Polyamide is also called nylon (Nylon), nylon, English name Polyamide, referred to as PA, which is the general term for polymers containing amide groups in the repeating unit of the macromolecular main chain. Polyamides can be prepared by ring-opening polymerization of lactams, or by polycondensation of diamines and dibasic acids. PA has good comprehensive properties, including mechanical properties, heat resistance, wear resistance, chemical resistance and self-lubricating properties, low friction coefficient, certain flame retardancy, easy processing, suitable for glass fiber and Other fillers are filled and modified to improve performance and expand application range. There are many varieties of PA, including PA6, PA66, PA11, PA12, PA46, PA61...

Examples

Embodiment 1

[0062] Place the sample 1 on the sample stage of the electron microscope, wait for the electron microscope to be vacuumed, apply a voltage of 20KV, and work at a distance of 10mm. Select a point with a flat surface and magnify it by 30 times for analysis. Record the elemental composition of the sample, the results are as figure 1 and as shown in Table 2, figure 1 Among them, the ordinate is the intensity of the peak, and the more the element content, the higher the peak. Table 2 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by the energy spectrometer.

[0063] Table 2 Elemental composition of sample 1

[0064] element

[0065] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

Embodiment 2

[0067] Place sample 2 on the electron microscope sample stage, wait for the electron microscope to be evacuated, apply a voltage of 20KV, and work at a distance of 10mm. Select a point with a flat surface and magnify it by 100 times for analysis. Record the elemental composition of the sample, the results are as figure 2 and as shown in Table 3, figure 2 Among them, the ordinate is the intensity of the peak, and the more the element content, the higher the peak. Table 3 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by the energy spectrometer. .

[0068] Table 3 Elemental composition of sample 2

[0069] element

[0070] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

Embodiment 3

[0072] Place the sample 3 on the sample stage of the electron microscope, wait for the electron microscope to be evacuated, apply a voltage of 20KV, and have a working distance of 10mm. Select a point with a flat surface and magnify it by 100 times for analysis. Record the elemental composition of the sample, the results are as image 3 and as shown in Table 4, image 3 Among them, the ordinate is the intensity of the peak, and the more element content, the higher the peak. Table 4 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by energy spectrometer.

[0073] Table 4 Elemental composition of sample 3

[0074] element

[0075] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

technical field

[0001] The invention relates to a method for identifying physical evidence such as fibers, in particular to a method for quickly and non-destructively distinguishing polyamide products. Background technique

[0002] Polyamide is also called nylon (Nylon), nylon, English name Polyamide, referred to as PA, which is the general term for polymers containing amide groups in the repeating unit of the macromolecular main chain. Polyamides can be prepared by ring-opening polymerization of lactams, or by polycondensation of diamines and dibasic acids. PA has good comprehensive properties, including mechanical properties, heat resistance, wear resistance, chemical resistance and self-lubricating properties, low friction coefficient, certain flame retardancy, easy processing, suitable for glass fiber and Other fillers are filled and modified to improve performance and expand application range. There are many varieties of PA, including PA6, PA66, PA11, PA12, PA46, PA61...

Examples

Embodiment 1

[0062] Place the sample 1 on the sample stage of the electron microscope, wait for the electron microscope to be vacuumed, apply a voltage of 20KV, and work at a distance of 10mm. Select a point with a flat surface and magnify it by 30 times for analysis. Record the elemental composition of the sample, the results are as figure 1 and as shown in Table 2, figure 1 Among them, the ordinate is the intensity of the peak, and the more the element content, the higher the peak. Table 2 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by the energy spectrometer.

[0063] Table 2 Elemental composition of sample 1

[0064] element

[0065] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

Embodiment 2

[0067] Place sample 2 on the electron microscope sample stage, wait for the electron microscope to be evacuated, apply a voltage of 20KV, and work at a distance of 10mm. Select a point with a flat surface and magnify it by 100 times for analysis. Record the elemental composition of the sample, the results are as figure 2 and as shown in Table 3, figure 2 Among them, the ordinate is the intensity of the peak, and the more the element content, the higher the peak. Table 3 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by the energy spectrometer. .

[0068] Table 3 Elemental composition of sample 2

[0069] element

[0070] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

Embodiment 3

[0072] Place the sample 3 on the sample stage of the electron microscope, wait for the electron microscope to be evacuated, apply a voltage of 20KV, and have a working distance of 10mm. Select a point with a flat surface and magnify it by 100 times for analysis. Record the elemental composition of the sample, the results are as image 3 and as shown in Table 4, image 3 Among them, the ordinate is the intensity of the peak, and the more element content, the higher the peak. Table 4 shows the weight percentage and atomic percentage of C, N, and O elements quantitatively analyzed by energy spectrometer.

[0073] Table 4 Elemental composition of sample 3

[0074] element

[0075] The same method was used to analyze and repeat the test five times, and the specific elemental composition of the samples was averaged to calculate the average percentage of C atoms. The results are shown in Table 6.

Images