Method for establishing optical characteristics of polymer and application of method in polymer identification

Abstract

The invention provides an application of a CIE map of a polymer, which is established by the method for establishing the optical characteristics of the polymer, in polymer identification. The invention also provides a method for establishing the optical characteristics of the polymer, and the method comprises the following steps: placing the polymer film on an optical platform, and collecting the color information of the polymer film; and extracting the color information, and drawing a CIE graph to obtain the CIE graph of the polymer film. The method aims at solving the problem that accurate recognition of polymer attributes is difficult to achieve due to the fact that a traditional polymer recognition method depends too much on professional chemical structure characterization equipment and method and is difficult to visually distinguish due to high similarity of morphology and texture. The CIE gallery established by the method for establishing the optical characteristics of the polymer provided by the invention can effectively make up for the defects of the traditional identification technology, can identify the sequence structure of the polymer, and has certain research value and application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of polymers, and in particular to a method for establishing optical characteristics of polymers and an application of the method in polymer identification. Background Art

[0002] The microstructure of polymer materials depends on their molecular structure and reflects information about their macroscopic properties, playing a key role in the design of polymer materials. As polymer materials continue to develop, their microstructures gradually become more similar, making it difficult to distinguish them visually.

[0003] At present, polymer characterization relies on traditional chemical characterization equipment and methods, which makes it difficult to distinguish polymer sequence structures. For example, the infrared spectra, nuclear magnetic resonance hydrogen spectra, and mass spectra of polymers produced by random copolymerization and block copolymerization are basically the same. Based on this, developing a new polymer property identification method has important research value and broad application prospects. Summary of the invention

[0004] The technical problem solved by the present invention is to provide a method for establishing the optical characteristics of polymers. The establishment method provided in this application can establish a CIE library of different polymers. Different polymers can be accurately identified based on the CIE images in the library, especially polymers with high similarity in morphology and texture can be efficiently distinguished.

[0005] In view of this, the present application provides a method for establishing optical characteristics of a polymer, comprising the following steps:

[0006] placing the polymer film on an optical platform and collecting color information of the polymer film;

[0007] The color information is extracted, and a CIE diagram is drawn to obtain a CIE diagram of the polymer film.

[0008] Preferably, the polymer film is PVC, TPU, EVA, PP, PET, PC, styrene-acrylic acid random copolymer film, styrene-acrylic acid block copolymer film, and is transparent and has no oriented structure.

[0009] Preferably, the thickness of the polymer film is 0.1 mm to 0.5 mm.

[0010] Preferably, the optical platform is composed of a white light source, a first polarizer, a second polarizer, a lens and a color CCD camera arranged in sequence, the polymer film is placed between the first polarizer and the second polarizer, and the second polarizer is arranged on the rotating platform.

[0011] Preferably, in the process of collecting the color information of the polymer film, the first polarizer and the second polarizer are adjusted to an extinction state, recorded as 0°, and the color information of the polymer film is collected for the first time; the angle of the second polarizer is adjusted to 5°~10°, and the color information of the polymer film is collected for the second time; the angle of the second polarizer is adjusted to 10°~20°, and the color information of the polymer film is collected for the third time, and the above steps are repeated several times.

[0012] Preferably, the color information of the polymer film is collected 37 to 73 times.

[0013] Preferably, before placing the polymer film on the optical platform, the method further comprises:

[0014] The polymer film is stretched.

[0015] Preferably, the degree of stretching is 20% to 200%.

[0016] The present application also provides the application of the CIE diagram of the polymer established by the establishment method in polymer identification.

[0017] The present application provides a method for establishing the optical characteristics of a polymer, which first places a polymer film on an optical platform, collects color information of the polymer film, then extracts the color information of the polymer film, draws a CIE diagram, and obtains the CIE diagram of the polymer film; The present application provides a method for establishing the optical characteristics of a polymer, which uses the color information of the polymer film to establish a CIE diagram library of the polymer. According to experimental results, the CIE diagrams of different polymers have different change trends, and even the CIE diagrams of random copolymers and block copolymers show different change trends. Therefore, in the process of identifying polymer properties, different polymers can be identified according to the expression of the CIE diagram. This method can accurately identify different polymers, especially efficiently distinguish polymers with high similarity in morphology and texture. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a method for establishing optical characteristics of a polymer provided by the present invention;

[0019] Figure 2 The imaging data collected by the optical path CCD after the polymer is stretched; (a) is PP, 0.5mm thickness, stretched 100%; (b) is TPU, 0.2mm thickness, stretched 100%;

[0020] Figure 3The CIE diagrams for different stretching degrees (0%, 50%, 100%, 150%, 200%) are determined by polymer type and thickness. In the figure, (a) is PP with a thickness of 0.5 mm; (b) is PVC with a thickness of 0.5 mm; (c) is TPU with a thickness of 0.5 mm;

[0021] Figure 4 CIE graphs for different thicknesses (0.2 / 0.3mm, 0.5mm) determined by polymer type and stretching degree; (a) PP, 100% stretching; (b) PVC, 100% stretching; (c) TPU, 100% stretching;

[0022] Figure 5 To determine the stretching degree and thickness, the CIE diagram for different polymer types, the stretching degree is 50% and the thickness is 0.2mm;

[0023] Figure 6 These are the CIE diagrams of styrene-acrylic random and block copolymer films stretched to different degrees. DETAILED DESCRIPTION

[0024] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0025] In view of the problem that the polymer property identification method in the prior art cannot effectively identify polymers with similar structure, morphology, and texture, the present invention provides a method for establishing polymer optical characteristics, which establishes a CIE library of different polymers. Different polymers can be accurately identified based on the CIE library, especially polymers with high similarity in morphology and texture. Specifically, an embodiment of the present invention discloses a method for establishing polymer optical characteristics, comprising the following steps:

[0026] placing the polymer film on an optical platform and collecting color information of the polymer film;

[0027] The color information is extracted, and a CIE diagram is drawn to obtain a CIE diagram of the polymer film.

[0028] In the method for establishing the optical characteristics of polymers in the present application, the present application first builds an optical platform, which is composed of a white light source, a first polarizer, a second polarizer, a lens, and a color CCD camera arranged in sequence, and the polymer film is placed on a sample placement platform between the first polarizer and the second polarizer, and the second polarizer is arranged on the rotating platform, and the rotating platform is used to realize the rotation of the second polarizer. On the optical platform, the emission line of the white light source, the center of the first polarizer, the center of the polymer film, the center of the second polarizer, and the lens are in a straight line to ensure that the color collection of the polymer film can be realized.

[0029] In the above optical platform, the white light source is a light source with a wide optical bandwidth, capable of emitting visible white light, including incandescent lamps, fluorescent lamps and other gas discharge lamps, etc. The present application does not specifically limit the type of white light source. A polarizer is an optical element that can convert natural light into polarized light, and has the functions of shielding and transmitting incident light; in the present application, the first polarizer and the second polarizer are preferably the same, and the types of the first polarizer and the second polarizer are not specifically limited in the present application. The color CCD camera is a digital camera that uses a charge coupled device (CCD) as a photosensitive element, which converts photons into electrons through the photoelectric effect, thereby capturing image information; the present application does not specifically limit the color CCD camera, and it can be selected according to the choice known to those skilled in the art.

[0030] After the optical platform is built, the polymer film is placed on the optical platform, and the color information of the polymer film is collected by a color CCD camera. The polymer film can be selected from polymer films well known to those skilled in the art, that is, the method for establishing the optical characteristics of polymers provided in this application is applicable to all polymers, and the method for establishing preferably collects the color information of all polymers, and finally obtains the CIE library of all polymers; in the specific embodiments provided in this application, the polymer film is PVC, TPU, EVA, PP, PET, PC, styrene-acrylic acid random copolymer film, styrene-acrylic acid block copolymer film, and is transparent and has no oriented structure; the above polymer film is purchased from the factory and does not contain other chemical additives. The thickness of the polymer film is 0.1mm to 0.5mm, and specifically, the thickness of the polymer film is 0.1mm, 0.2mm, 0.3mm or 0.5mm.

[0031] The present application preferably stretches the polymer film and then collects the color information of the polymer film; the degree of stretching is 20-200%, specifically, the degree of stretching is 20%, 100%, 150%, 200%. The temperature of the polymer film during the stretching process should be controlled near its hot stretching temperature, such as 140°C during the stretching process of PP film.

[0032] In the process of collecting the color information of the polymer film, the first polarizer and the second polarizer are adjusted to the extinction state, recorded as 0°, and the color information of the polymer film is collected for the first time, and the angle of the second polarizer is adjusted to 5°~10°. The color information of the polymer film is collected for the second time, and the angle of the second polarizer is adjusted to 10°~20°. The color information of the polymer film is collected for the third time, and the above steps are repeated several times.

[0033] Furthermore, in the process of collecting color information of the polymer film, the first polarizer and the second polarizer are adjusted to an extinction state, recorded as 0°, and the color information of the polymer film is collected for the first time, and the angle of the second polarizer is adjusted to 10°. The color information of the polymer film is collected for the second time, and the angle of the second polarizer is adjusted to 20°. The color information of the polymer film is collected for the third time, and the above steps are repeated until the information of the polymer film within the complete angle range is collected.

[0034] According to the above-mentioned collection angle, the color information of the polymer film is collected 37 to 73 times. In a specific embodiment, the color information of the polymer film is collected 37 times.

[0035] The present application then extracts the color information and draws a CIE diagram, thereby obtaining a CIE diagram of the polymer film. In the present application, the above method can be used to collect all polymer film information, obtain the color information of all polymer films, and finally obtain the CIE diagram of all polymer films, which is equivalent to forming a database of CIE diagrams of polymer films. The CIE diagram is a plane diagram represented by chromaticity coordinates in colorimetry. The method for establishing the optical characteristics of polymers provided in the present application realizes the identification of different polymers through the different change trends of the CIE diagram.

[0036] The schematic diagram of the method for establishing the optical characteristics of polymers provided in this application is as follows Figure 1 As shown, it includes sequentially collecting color information of the polymer film through an optical platform, and obtaining a CIE diagram of the polymer film according to the color information.

[0037] The present application also provides the application of the CIE diagram of the polymer established by the above-mentioned establishment method in polymer identification.

[0038] The establishment method provided in the present application can obtain CIE diagrams of various polymers and form a CIE diagram database of polymers. When identifying polymers, the polymers can be identified based on the expression form of the CIE diagram of the polymers. In particular, the establishment method provided in the present application can effectively distinguish between polymers with high similarity in morphology and texture, such as random polymers and block polymers, effectively making up for the defects of traditional polymer identification.

[0039] In order to further understand the present invention, the method for establishing the optical characteristics of polymers and applications provided by the present invention are described in detail below in conjunction with the embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0040] Example 1

[0041] Optical platform construction The optical platform in the present invention includes a light source, a first linear polarizer, a sample placement table, a second linear polarizer, a rotating table, a lens, and a color CCD, wherein the light source is a white light source, and the polymer color information is collected by CCD. The order of placement from left to right is white light source, first linear polarizer, sample placement table, second linear polarizer, rotating table, lens, and color CCD.

[0042] Example 2

[0043] Optical test of PVC film PVC films with thickness of 0.2 mm and 0.5 mm were stretched by 0%, 50%, 100%, 150% and 200% respectively, and placed on the sample stage of the optical platform built in Example 1 to collect color information. The two polarizers were first adjusted to the extinction state, recorded as 0°, and the color information was collected once. After that, the color information was collected every 10°. Each polymer film was collected 37 times, and the collected color information was processed to draw a CIE diagram. The results are shown in FIG. Figure 3 Middle (b) Figure, Figure 4 Middle (b) Figure, Figure 5 shown.

[0044] Example 3

[0045] Optical test of TPU film: TPU films with thickness of 0.1, 0.2 mm and 0.5 mm were stretched by 0%, 50%, 100%, 150% and 200% respectively and placed on the sample stage of the optical platform to collect color information. The specific steps refer to Example 2. The results are shown in Figure 2 (b) Figure, Figure 3 (c) Figure and Figure 4 (c) As shown in the figure, Figure 5 shown.

[0046] Example 4

[0047] EVA film optical test: 0.1 and 0.2 mm thick EVA films were stretched by 0%, 50%, 100%, 150%, and 200% respectively, and placed on the sample stage of the optical platform to collect color information. The specific steps refer to Example 2. The results are as follows Figure 5 shown.

[0048] Example 5

[0049] Optical test of PET film: PET films with thickness of 0.2 mm and 0.5 mm were stretched by 0%, 50%, 100%, 150% and 200% respectively, and placed on the sample stage of the optical platform to collect color information. The specific steps refer to Example 2. The results are shown in Figure 5 shown.

[0050] Example 6

[0051] PP film optical test PP films with thickness of 0.3 mm and 0.5 mm were stretched by 0%, 50%, 100%, 150%, and 200% respectively, and placed on the sample stage of the optical platform to collect color information. The specific steps refer to Example 2. The results are as follows Figure 2 (a) Figure, Figure 3 (a) Figure, Figure 4 (a) As shown in the figure, it can be found that as the angle of the two polarizers changes, the image collected by the color CCD shows different color changes.

[0052] Example 7

[0053] PC film optical test: PC films with thickness of 0.2 mm and 0.5 mm were stretched by 0%, 50%, 100%, 150%, and 200% respectively, and placed on the sample stage of the optical platform to collect color information. The specific steps refer to Example 2. The results are as follows Figure 5 shown.

[0054] As shown in Table 1, Table 1 is a statistical table of the stretching degree and thickness of the polymers used in Examples 2 to 7;

[0055] Table 1 Statistical table of stretching degree and thickness of polymers used in Examples 2 to 7

[0056]

[0057] Example 8

[0058] Styrene and acrylic acid raft polymerization, film preparation and optical testing Determine the appropriate proportion of styrene, acrylic acid, initiator azobisisobutyronitrile, and raft reagent ethylene trithiocarbonate, feed them once or in batches to obtain styrene-acrylic acid random copolymer PS-co-PAA and styrene-acrylic acid block copolymer PS-b-PAA; dissolve the polymer in tetrahydrofuran, lay the film, and obtain PS-co-PAA polymer film and PS-b-PAA polymer film respectively. Stretch the PS-co-PAA and PS-b-PAA polymer films by 0%, 100%, 200%, and 300%, respectively, and place them on the sample stage of the optical platform to collect color information. Refer to Example 2 for the specific steps. The results are as follows Figure 6 shown.

[0059] Example 9

[0060] More than 5,000 images collected in Examples 2 to 8 were processed and CIE diagrams were drawn.

[0061] according to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 It can be seen that:

[0062] 1. If Figure 2 As shown by Figure 2 It can be seen that when the polarizer is at different relative angles, the PP and TPU films stretched 100% show different color changes, and the collected color information is processed to obtain the CIE diagram for subsequent analysis;

[0063] 2. If Figure 3 As shown in (a), when the degree of stretching changes, the CIE graph of PP with a thickness of 0.5 mm has different performances; Figure 3 (a) Figure 3 (b) and Figure 3 (c), it can be found that the same polymer shows different change trends on the CIE graph when the stretching degree changes, and the change trends of the CIE graphs of different polymers at the same stretching degree are also different;

[0064] 3. From Figure 4 (a) It can be seen that the CIE graph has different change trends when PP is stretched 100% and the thickness is 0.3mm and 0.5mm. Figure 4 (b) It can be seen that the CIE graph has different change trends when PVC is stretched 100% and the thickness is 0.3mm and 0.5mm. Figure 4 (c) It can be seen that the CIE graph has different change trends when TPU is stretched 100% and the thickness is 0.3mm and 0.5mm; Figure 4 It can be found that the same polymer shows different change trends on the CIE diagram when the thickness is different, and different polymers also show different change trends on the CIE diagram when the thickness is different;

[0065] 4. Contrast Figure 5 The CIE diagrams of different polymers under certain stretching degree and thickness show that the CIE diagrams of different polymers show different change trends;

[0066] 5. Contrast Figure 6 The CIE diagrams of the PS-co-PAA polymer film and the PS-b-PAA polymer film after stretching. The CIE diagrams of different polymers also show different change trends. The CIE diagrams of the same polymer under different stretching degrees also show different change trends.

[0067] In summary, this method has a certain ability to identify different film thicknesses, stretching degrees, polymer types, and random and block polymers, so it can be used as a new method for identifying polymer properties.

[0068] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0069] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for establishing the optical characteristics of a polymer, comprising the following steps: placing the polymer film on an optical platform and collecting color information of the polymer film; The color information is extracted, and a CIE diagram is drawn to obtain a CIE diagram of the polymer film.

2. The establishment method according to claim 1, characterized in that: The polymer film is PVC, TPU, EVA, PP, PET, PC, styrene-acrylic acid random copolymer film, styrene-acrylic acid block copolymer film, and is transparent and has no oriented structure.

3. The establishment method according to claim 1, characterized in that: The thickness of the polymer film is 0.1 mm to 0.5 mm.

4. The establishment method according to claim 1, characterized in that: The optical platform is composed of a white light source, a first polarizer, a second polarizer, a lens and a color CCD camera which are arranged in sequence. The polymer film is placed between the first polarizer and the second polarizer, and the second polarizer is arranged on the rotating platform.

5. The establishment method according to claim 4, characterized in that: In the process of collecting the color information of the polymer film, the first polarizer and the second polarizer are adjusted to the extinction state, recorded as 0°, and the color information of the polymer film is collected for the first time; the angle of the second polarizer is adjusted to 5°~10°, and the color information of the polymer film is collected for the second time; the angle of the second polarizer is adjusted to 10°~20°, and the color information of the polymer film is collected for the third time, and the above steps are repeated several times.

6. The establishment method according to claim 1 or 5, characterized in that: The color information of the polymer film is collected 37 to 73 times.

7. The establishment method according to any one of claims 1 to 6, characterized in that: Before placing the polymer film on the optical platform, the step further comprises: The polymer film is stretched.

8. The establishment method according to claim 7, characterized in that: The degree of stretching is 20% to 200%.

9. Application of the CIE diagram of a polymer established by the establishment method according to any one of claims 1 to 8 in polymer identification.

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