Method for fast and non-destructive differentiation of polyamide products

Abstract

The invention relates to a method for rapid and non-destructive differentiation of polyamide articles. The method of the present invention comprises the following steps: determine the analysis part of the product through a scanning electron microscope, use an energy spectrometer to perform elemental analysis, calculate the atomic percentage of carbon in the product, and identify the measured polyamide product according to the content of the carbon element. The first type of polyamide product is also the second type of polyamide product; among them, the first type of polyamide product is a product formed by the polymerization of amide monomers containing more than 10 carbon atoms in the largest monomer; the second type of polyamide product Amide products are products obtained by polymerizing amide monomers containing 7 or less carbon atoms in the largest monomer. Using the method of the present invention to analyze polyamide products will not cause loss to the sample, so that the sample can be retained; the method of the present invention can quickly distinguish polyamide products, and the operation is simple; the present invention also enriches the fiber identification method and provides fiber identification. new ideas.

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 weight percentage atomic percent C 64.25 69.32 N 14.94 13.82 O 20.81 16.85 Total 100.00

[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...

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 weight percentage atomic percent C 65.53 70.53 N 14.13 13.04 O 20.34 16.44 Total 100.00

[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 ...

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 weight percentage atomic percent C 71.28 75.58 N 13.76 12.51 O 14.96 11.91 Total 100.00

[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 ...

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 weight percentage atomic percent C 64.25 69.32 N 14.94 13.82 O 20.81 16.85 Total 100.00

[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...

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 weight percentage atomic percent C 65.53 70.53 N 14.13 13.04 O 20.34 16.44 Total 100.00

[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 ...

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 weight percentage atomic percent C 71.28 75.58 N 13.76 12.51 O 14.96 11.91 Total 100.00

[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 ...

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