Method and system for detecting water swelling of macromolecular water-absorbing material
Through the combination of laser scanning technology and weight measurement, the problem of inconsistent traditional detection results is solved, and the accurate evaluation of the water absorption and expansion rate of polymer water absorption materials is achieved, which promotes in-depth research and optimization of materials.
Patent Information
- Application Number
- CN202411682403.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-02-25
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The water absorption expansion detection of traditional polymer water absorption materials is affected by human subjective factors, resulting in inconsistent detection results and incomplete performance evaluation.
Three-dimensional scanning is performed using laser scanning technology, combining weight measurement, water absorption and expansion rate are calculated, and comprehensive evaluation is performed through hierarchical structure model and AHP method.
Accurate assessment of the water absorption and expansion rates of polymer water absorption materials is achieved, providing a comprehensive understanding of material behavior, and promoting the development of new materials and improvement of existing materials.
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Figure CN119510206A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of expansion rate detection, and in particular to a method and system for detecting water absorption and expansion of polymer water-absorbing materials. Background Art
[0002] Polymer absorbent materials are highly absorbent polymer materials that can absorb and retain water far exceeding their own weight. Such materials are usually composed of polymers with hydrophilic groups, such as polyacrylates and polyacrylamide. They are widely used in many fields such as agriculture, health care, and daily necessities. For example, in agriculture, they can be used as soil moisturizers to improve water utilization in arid areas; in the medical field, they are used to make absorbent sanitary products such as diapers and sanitary napkins. The core characteristics of these materials are their strong water absorption capacity and good water retention. When exposed to water, these polymer materials will expand rapidly to form a gel-like substance. The principle is that the interaction between the hydrophilic groups in the polymer chain and the water molecules leads to the formation of a large number of tiny water molecule spaces inside the material, thereby expanding the volume of the material and locking in water. With the advancement of science and technology, the application scope of polymer absorbent materials continues to expand, such as in environmental protection for wastewater treatment, or in the biomedical field for drug sustained release systems. These applications have not only promoted the development of related industries, but also had a profound impact on improving the quality of human life.
[0003] At present, in order to ensure that polymer water-absorbing materials can be effectively used in the intended applications, it is necessary to test the water absorption and expansion capacity of polymer water-absorbing materials. However, the traditional water absorption and expansion test of polymer water-absorbing materials is affected by human subjective factors, such as the operator's experience and subjective judgment, and only focuses on a certain performance parameter of the material. It lacks a comprehensive evaluation of multiple performance parameters, which will lead to inconsistent test results of the water absorption and expansion test of polymer water-absorbing materials, resulting in incomplete performance evaluation of polymer water-absorbing materials.
[0004] Currently, no effective solution has been proposed for the problems in the related technologies. Summary of the invention
[0005] In view of this, the present invention provides a method and system for detecting water absorption and swelling of polymer water absorbent materials, so as to solve the problem that the conventional water absorption and swelling detection of polymer water absorbent materials is affected by human subjective factors, which may lead to inconsistent test results of the water absorption and swelling detection of polymer water absorbent materials and incomplete performance evaluation of polymer water absorbent materials.
[0006] In order to solve the above problems, the specific technical solutions adopted by the present invention are as follows: According to one aspect of the present invention, a method for detecting the swelling of a polymer water-absorbing material upon absorption of water is provided, the method comprising the following steps: S1. Preparing a polymer water-absorbing material based on a polymer-based material and a water-absorbing additive; S2, performing three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; S3, immersing the polymer water-absorbing material in water for water absorption and swelling treatment, and calculating the water absorption rate of the polymer water-absorbing material according to the weight before and after the polymer water-absorbing material; S4, performing three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain final three-dimensional point cloud data; S5. Analyze the expansion rate of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data; S6. Evaluate the water absorption and expansion properties of the polymer water absorbent material based on its water absorption rate and expansion rate.
[0007] Preferably, immersing the polymer water-absorbing material in water for water absorption and swelling treatment, and calculating the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material comprises the following steps: S31, measuring the initial weight of the prepared polymer water-absorbing material before water absorption; S32, placing the prepared polymer water-absorbing material into a preset water tank for soaking; S33, after reaching the preset soaking time, taking out the polymer water-absorbing material from the water tank; S34, measuring the weight of the polymer water-absorbing material after absorbing water after the immersion, to obtain a final weight; S35. Calculate the water absorption rate of the polymer water-absorbing material according to the initial weight and the final weight.
[0008] Preferably, performing expansion rate analysis on the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data comprises the following steps: S51, preprocessing the initial three-dimensional point cloud data and the final three-dimensional point cloud data respectively; S52, respectively extracting the contour of the polymer water-absorbing material from the preprocessed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial contour and a final contour; S53, based on the initial contour and the final contour, using a grid algorithm to calculate the volume of the polymer water-absorbing material before and after water absorption and expansion; S54. Calculate the expansion rate of the polymer water-absorbing material based on the volume of the polymer water-absorbing material before and after the water absorption and expansion.
[0009] Preferably, respectively extracting the contour of the polymer water-absorbing material from the preprocessed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain the initial contour and the final contour comprises the following steps: S521, based on the point cloud slicing algorithm, respectively perform point cloud slicing on the initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial sheet point cloud and a final sheet point cloud; S522, extracting contour feature points from the initial sheet point cloud and the final sheet point cloud respectively by using a geometric feature point extraction algorithm, where the contour feature points include edge points and inflection points; S523, performing curve fitting on the contour feature points of the initial sheet point cloud and the final sheet point cloud respectively by using the least square method; S524, integrating the fitted curves to construct the initial profile and final profile of the polymer water-absorbing material.
[0010] Preferably, based on a point cloud slicing algorithm, point cloud slicing is performed on the initial three-dimensional point cloud data and the final three-dimensional point cloud data respectively to obtain the initial sheet point cloud and the final sheet point cloud, which includes the following steps: S5211, respectively perform coordinate transformation on the initial 3D point cloud data and the final 3D point cloud data, and transform the initial 3D point cloud data and the final 3D point cloud data to a direction in which the center line is parallel to the positive direction of the z-axis and the bottom surface is parallel to the xoy plane; S5212, establishing a local coordinate system at any data point of the initial three-dimensional point cloud data and the final three-dimensional point cloud data, and setting the positive direction of the x-axis as the direction of the slice; S5213, respectively obtaining the maximum value and the minimum value of the initial three-dimensional point cloud data and the final three-dimensional point cloud data in the x-axis direction; S5214, respectively dividing the initial three-dimensional point cloud data and the final three-dimensional point cloud data into m equally spaced slices in the x-axis direction, generating m groups of projection planes in the same direction as the x-axis; S5215. A plane perpendicular to the slicing direction is used as a reference plane, and the initial three-dimensional point cloud data and the final three-dimensional point cloud data are projected onto the reference plane respectively to obtain an initial sheet point cloud and a final sheet point cloud.
[0011] Preferably, based on the initial contour and the final contour, calculating the volume of the polymer water-absorbing material before and after water absorption and expansion using a grid algorithm comprises the following steps: S531, placing the initial outline and the final outline on the same plane, and establishing a grid; S532, in the grid, for each square of the initial outline and the final outline, using interpolation method to solve the elevation value of each vertex; S533, calculating the volume of each square according to the obtained elevation value; S534, respectively accumulating the volume of each square in the initial outline and the final outline to obtain the volume of the polymer water-absorbing material before and after water absorption and expansion, and using it as the initial state volume and the final state volume.
[0012] Preferably, evaluating the water absorption and expansion property of the polymer water-absorbing material according to the water absorption rate and expansion rate of the polymer water-absorbing material comprises the following steps: S61, determining the water absorption density of the polymer water absorbent material according to the mass and volume of the polymer water absorbent material after absorbing water; S62. The water absorption rate, expansion rate and water absorption density of polymer water-absorbing materials are used as evaluation factors and a hierarchical structure model is established; S63, comparing the evaluation factors by AHP method, and determining the relative weight vector of the evaluation factors; S64. Based on the relative weight vector of the evaluation factors, the evaluation results of the water absorption and swelling performance of the polymer water-absorbing material are calculated.
[0013] Preferably, comparing the evaluation factors by the AHP method and determining the relative weight vectors of the evaluation factors includes the following steps: S631, compare the evaluation factors in pairs, and establish a judgment matrix based on the comparison results; S632, using eigenvalue decomposition method to solve the eigenvalues and eigenvectors of the judgment matrix; S633. Normalize the characteristic vector to obtain the relative weight vector of the evaluation factors.
[0014] Preferably, the calculation of the water absorption and swelling performance evaluation result of the polymer water-absorbing material based on the relative weight vector of the evaluation factors includes the following steps: S641. Calculate the weighted score of each participating factor by weighted average method according to the relative weight vector of the participating factors; S642. Calculate the water absorption and swelling performance evaluation results of the polymer water-absorbing material using a numerical calculation method based on the weighted scores of each evaluation factor; S643. Based on the evaluation results, the composition of the polymer-based material and the water-absorbing additive is improved and the water absorption and swelling properties of the polymer water-absorbing material are optimized.
[0015] According to another aspect of the present invention, a system for detecting water absorption and swelling of a polymer water-absorbing material is provided, the system for detecting water absorption and swelling of a polymer water-absorbing material comprising: a material preparation module, an initial data scanning module, a water absorption and swelling processing module, a final data scanning module, a swelling ratio analysis module and a swelling property evaluation module, wherein the material preparation module, the initial data scanning module, the water absorption and swelling processing module, the final data scanning module, the swelling ratio analysis module and the swelling property evaluation module are sequentially connected; A material preparation module is used to prepare polymer water-absorbing materials based on polymer-based materials and water-absorbing additives; The initial data scanning module is used to perform three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; A water absorption and expansion treatment module is used to immerse the polymer water-absorbing material in water for water absorption and expansion treatment, and calculate the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material; The final data scanning module is used to perform three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain the final three-dimensional point cloud data; An expansion rate analysis module is used to analyze the expansion rate of polymer water-absorbing materials based on initial 3D point cloud data and final 3D point cloud data; The expansion evaluation module is used to evaluate the water absorption expansion of the polymer water absorbent material according to the water absorption rate and expansion rate of the polymer water absorbent material.
[0016] The beneficial effects of the present invention are: 1. The present invention can very accurately evaluate the water absorption and expansion rate of polymer water-absorbing materials by combining weight measurement and three-dimensional laser scanning technology. The three-dimensional scanning provides a detailed view of the volume change of the material before and after water absorption, while the weight measurement provides accurate data on the water absorption rate. The combination of the two data can provide a comprehensive understanding of the material behavior, so that the behavior of polymer water-absorbing materials can be studied more deeply, thereby promoting the development of new materials and the improvement of existing materials.
[0017] 2. The present invention can remove noise and irrelevant data from the original point cloud through preprocessing and contour extraction, and extract key information for analysis. Coordinate transformation and point cloud slicing can simplify the three-dimensional shape into a series of two-dimensional slices, making the problem easier to handle. At the same time, by slicing in the local coordinate system, the details of the shape can be more easily captured. The use of geometric feature point extraction and curve fitting technology can extract accurate shape contours from point cloud data, providing a basis for subsequent volume calculation. The use of grid algorithm for volume calculation can simplify the problem by decomposing complex shapes into simple small units, improve computing efficiency, and provide detailed and comprehensive data support for the research and application of polymer absorbent materials.
[0018] 3. The present invention determines the water absorption density by measuring the mass and volume after water absorption, and uses the AHP method for weight allocation and comprehensive scoring to ensure that the evaluation process is scientific and objective, and can comprehensively consider the influence of various factors. The judgment matrix established by pairwise comparison helps to quantify the relative importance of the participating factors. The eigenvalue decomposition method and the normalization of the eigenvector provide a mathematically reasonable weight vector for the participating factors, ensuring that the decision-making process has a solid mathematical foundation. It not only provides a comprehensive, scientific and accurate evaluation framework, but also promotes the decision-making process based on data and analysis, which is conducive to the continuous improvement and optimization of polymer water-absorbing materials. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 is a flow chart of a method for detecting water absorption and swelling of a polymer water-absorbing material according to an embodiment of the present invention; Figure 2 The present invention is a block diagram of a system for detecting water absorption and swelling of a polymer water-absorbing material according to an embodiment of the present invention.
[0020] In the figure: 1. Material preparation module; 2. Initial data scanning module; 3. Water absorption and expansion treatment module; 4. Final data scanning module; 5. Expansion rate analysis module; 6. Expansion evaluation module. DETAILED DESCRIPTION
[0021] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.
[0022] According to an embodiment of the present invention, a method and system for detecting water absorption and swelling of a polymer water-absorbing material are provided.
[0023] The present invention is further described with reference to the accompanying drawings and specific embodiments. Figure 1As shown, according to one embodiment of the present invention, a method for detecting the swelling of a polymer water-absorbing material upon water absorption is provided, and the method for detecting the swelling of a polymer water-absorbing material upon water absorption comprises the following steps: S1. Preparing a polymer water-absorbing material based on a polymer-based material and a water-absorbing additive; Specifically, polymer-based materials include sodium polyacrylate (SAP), polyvinyl alcohol (PVA), polyacrylamide, etc., and water-absorbing additives include cross-linking agents (such as multi-functional cross-linking agents), plasticizers, surfactants, etc.
[0024] Wherein, the preparation of the polymer water-absorbing material comprises the following steps: Processing of polymer-based materials, such as drying, pulverizing or chemical modification, to improve their compatibility with additives; The polymer-based material and the water-absorbing additive are mixed in a certain proportion, and the mixing is achieved by mechanical stirring, solvent mixing or melt mixing; The polymerization and cross-linking steps are carried out by chemical reactions (such as heating or adding an initiator) to form a polymer with a three-dimensional network structure; After the polymer water-absorbing material is formed, the solvent or water is removed through a drying process, and it may need to be crushed or cut into the desired shape and size.
[0025] S2, performing three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; It should be noted that according to the size, shape and required resolution of the polymer water-absorbing material, a suitable laser scanner is selected, and parameters such as scanning speed, resolution, scanning range and angle are set. Then the polymer water-absorbing material is placed on the working platform of the scanner and the scanning program is started. The laser scanner will emit a laser beam. When the laser beam hits the surface of the sample, it will be reflected back to the detector on the instrument. By measuring the reflection time of the laser beam, the scanner can calculate the exact position of the point on the surface of the sample in space. During the scanning process, the device will generate a point cloud data set composed of a large number of points in space. Each point has its coordinates in three-dimensional space. These points together form a three-dimensional digital copy of the sample.
[0026] S3, immersing the polymer water-absorbing material in water for water absorption and swelling treatment, and calculating the water absorption rate of the polymer water-absorbing material according to the weight before and after the polymer water-absorbing material; As a preferred embodiment, immersing the polymer water-absorbing material in water for water absorption and swelling treatment, and calculating the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material comprises the following steps: S31, measuring the initial weight of the prepared polymer water-absorbing material before water absorption; S32, placing the prepared polymer water-absorbing material into a preset water tank for soaking; S33, after reaching the preset soaking time, taking out the polymer water-absorbing material from the water tank; S34, measuring the weight of the polymer water-absorbing material after absorbing water after the immersion, to obtain a final weight; S35. Calculate the water absorption rate of the polymer water-absorbing material according to the initial weight and the final weight.
[0027] Specifically, the weight of the water absorbed by the material is obtained by subtracting the initial weight before water absorption from the final weight after water absorption. Then, this weight difference is divided by the initial weight, and the result is the water absorption rate of the polymer absorbent material.
[0028] S4, performing three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain final three-dimensional point cloud data; It should be noted that the three-dimensional scanning of the polymer water-absorbing material after the water absorption and swelling treatment by laser scanning technology is the same as the scanning method of the above step S2.
[0029] S5. Analyze the expansion rate of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data; As a preferred embodiment, the expansion rate analysis of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data includes the following steps: S51, preprocessing the initial three-dimensional point cloud data and the final three-dimensional point cloud data respectively; Specifically, preprocessing includes data cleaning, filtering, downsampling, etc.
[0030] Among them, data cleaning is used to remove abnormal points or noise in the three-dimensional point cloud, which can be achieved through statistical analysis methods (such as calculating the average distance from each point in the point cloud to its neighboring points), and then removing those points far from the average distance.
[0031] Filtering is the use of filtering algorithms (such as Gaussian filtering and median filtering) to smooth point cloud data and reduce the impact of noise, which helps to improve the accuracy and robustness of subsequent processing steps.
[0032] Downsampling is if the point cloud data is very dense, downsampling is needed to reduce the number of data points, thereby reducing the computational complexity of subsequent processing. Common downsampling methods include voxel grid filters and random sampling.
[0033] S52, respectively extracting the contour of the polymer water-absorbing material from the preprocessed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial contour and a final contour; As a preferred embodiment, respectively extracting the contour of the polymer water-absorbing material from the pre-processed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain the initial contour and the final contour includes the following steps: S521, based on the point cloud slicing algorithm, respectively perform point cloud slicing on the initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial sheet point cloud and a final sheet point cloud; As a preferred implementation, based on the point cloud slicing algorithm, the initial three-dimensional point cloud data and the final three-dimensional point cloud data are respectively sliced to obtain the initial sheet point cloud and the final sheet point cloud, including the following steps: S5211, respectively perform coordinate transformation on the initial three-dimensional point cloud data and the final three-dimensional point cloud data, and transform the initial three-dimensional point cloud data and the final three-dimensional point cloud data to a direction in which the center line is parallel to the positive direction of the z-axis and the bottom surface is parallel to the xoy plane; It should be noted that, first, the center line and bottom surface direction of the point cloud data set are determined by calculating the principal components of the point cloud or fitting a straight line model. The rotation angle is calculated by comparing the direction of the current center line and the direction of the z-axis. The rotation axis is obtained by vector cross product based on the normal direction of the current center line and the z-axis. A rotation matrix is constructed based on the rotation angle and the rotation axis, and the rotation matrix is applied to each point in each point cloud data set. This process changes the direction of the point cloud but not its shape. After the rotation, the point cloud is translated along the z-axis so that its bottom surface is aligned with the xoy plane.
[0034] S5212, establishing a local coordinate system at any data point of the initial three-dimensional point cloud data and the final three-dimensional point cloud data, and setting the positive direction of the x-axis as the direction of the slice; S5213, respectively obtaining the maximum value and the minimum value of the initial three-dimensional point cloud data and the final three-dimensional point cloud data in the x-axis direction; S5214, respectively dividing the initial three-dimensional point cloud data and the final three-dimensional point cloud data into m equally spaced slices in the x-axis direction, generating m groups of projection planes in the same direction as the x-axis; It should be noted that for each point cloud dataset, the overall range of the slice is defined according to the minimum and maximum values of the point cloud in the x-axis direction, and then m slice planes are defined. Each plane can be regarded as a virtual "wall" located at a specific position on the x-axis. For each point cloud dataset, each data point is assigned to the corresponding slice according to its position on the x-axis. Specifically, if the x-coordinate of a point is between the positions of two planes, then the point belongs to the slice defined by the two planes. For each slice, a projection plane is generated.
[0035] S5215. A plane perpendicular to the slicing direction is used as a reference plane, and the initial three-dimensional point cloud data and the final three-dimensional point cloud data are projected onto the reference plane to obtain an initial sheet point cloud and a final sheet point cloud.
[0036] It should be noted that each point of the initial three-dimensional point cloud data and the final three-dimensional point cloud data is projected onto the reference plane, that is, the x coordinate of each point is replaced by the x coordinate of the reference plane.
[0037] S522, extracting contour feature points from the initial sheet point cloud and the final sheet point cloud respectively by using a geometric feature point extraction algorithm, where the contour feature points include edge points and inflection points; It should be noted that, according to the established local coordinate system, for each point in the point cloud, its normal vector is calculated, and then a detection window with a preset side length is established with each point as the center. The change of the point cloud density is analyzed within the window. If the point cloud density changes significantly in a certain direction, the point is considered to be an edge point. If the density changes significantly in two or more directions, it may be an inflection point. All point cloud data are traversed, and inflection points and edge points are extracted according to the above standards.
[0038] S523, performing curve fitting on the contour feature points of the initial sheet point cloud and the final sheet point cloud respectively by using the least square method; It should be noted that, according to the distribution and shape of the feature points, a linear model, a quadratic or higher-order polynomial model is selected to fit the data, and a least squares problem is constructed based on the selected model. The parameters are solved by minimizing the sum of squared errors. Specifically, the parameter value that minimizes the sum of squares of the vertical distances from all data points to the fitting curve is calculated, and a set of equations is established using the data points. The model parameters are obtained by solving these equations, and then the error between the fitting curve and the actual data points is calculated to determine the accuracy of the fit.
[0039] S524, integrating the fitted curves to construct the initial profile and final profile of the polymer water-absorbing material.
[0040] It should be noted that a series of coordinate points are extracted from the fitted curve. These points should be dense enough to ensure the continuity and integrity of the contour. The coordinate points of the initial and final contour curves are compared to identify the main shape change areas, and then the initial and final contour curves are merged to form a complete contour change map.
[0041] S53, based on the initial contour and the final contour, using a grid algorithm to calculate the volume of the polymer water-absorbing material before and after water absorption and expansion; As a preferred embodiment, based on the initial contour and the final contour, the volume of the polymer water-absorbing material before and after water absorption and expansion is calculated using a grid algorithm, including the following steps: S531, placing the initial outline and the final outline on the same plane, and establishing a grid; It should be noted that the size of the grid is determined according to the characteristics of the contour, and the size should be small enough to capture the important features of the contour. The grid is created on the plane to ensure that it completely covers the initial and final contours.
[0042] S532, in the grid, for each square of the initial outline and the final outline, using interpolation method to solve the elevation value of each vertex; It should be noted that interpolation methods include linear interpolation, polynomial interpolation, spline interpolation, etc. The elevation value is the vertical distance of a point in space relative to a reference surface or datum surface.
[0043] Among them, solving the elevation value of each vertex by interpolation method includes the following steps: Extract vertex data from the initial and final contours, and record the elevation values of points on the contours; For each square in the grid, the elevation values of non-contour points are calculated using linear interpolation method, and these values are known and will be used as the reference points for interpolation; Apply linear interpolation to calculate the elevation of non-contour points in the grid based on the elevation values and position information of adjacent vertices; Verify the calculated elevation values to ensure that the interpolation results are reasonable and reliable.
[0044] S533, calculating the volume of each square according to the obtained elevation value; It should be noted that, first, determine the boundaries of each square, multiply the length and width of the square to get the area, and multiply the area of the square by the elevation value of the internal point of the square to get the volume of the square.
[0045] S534, respectively accumulating the volume of each square in the initial outline and the final outline to obtain the volume of the polymer water-absorbing material before and after water absorption and expansion, and using it as the initial state volume and the final state volume.
[0046] S54. Calculate the expansion rate of the polymer water-absorbing material based on the volume of the polymer water-absorbing material before and after the water absorption and expansion.
[0047] Specifically, the volume difference of the material expansion is obtained by subtracting the volume of the initial state before water absorption from the final state volume after water absorption. Then, this expanded volume difference is divided by the initial state volume. The result is the expansion rate of the polymer water-absorbing material.
[0048] Specifically, the present invention can remove noise and irrelevant data from the original point cloud through preprocessing and contour extraction, and extract key information for analysis. Coordinate transformation and point cloud slicing can simplify the three-dimensional shape into a series of two-dimensional slices, making the problem easier to handle. At the same time, by slicing in the local coordinate system, the details of the shape can be more easily captured. The use of geometric feature point extraction and curve fitting technology can extract accurate shape contours from point cloud data, providing a basis for subsequent volume calculation. The use of a grid algorithm for volume calculation can simplify the problem by decomposing complex shapes into simple small units, improve computing efficiency, and provide detailed and comprehensive data support for the research and application of polymer absorbent materials.
[0049] S6. Evaluate the water absorption and expansion properties of the polymer water absorbent material based on its water absorption rate and expansion rate.
[0050] As a preferred embodiment, evaluating the water absorption and expansion property of the polymer water absorbent material according to the water absorption rate and expansion rate of the polymer water absorbent material comprises the following steps: S61, determining the water absorption density of the polymer water absorbent material according to the mass and volume of the polymer water absorbent material after absorbing water; Specifically, the water absorption density of the polymer water-absorbing material is obtained by dividing the mass after water absorption by the volume after water absorption.
[0051] S62. The water absorption rate, expansion rate and water absorption density of polymer water-absorbing materials are used as evaluation factors and a hierarchical structure model is established; It should be noted that the water absorption performance of polymer water-absorbing materials is taken as the evaluation target, the target is decomposed into a hierarchical structure, and the factors of each level are determined, including water absorption rate, expansion rate and water absorption density. Water absorption rate, expansion rate and water absorption density are taken as the bottom evaluation factors of the hierarchical structure.
[0052] S63, comparing the evaluation factors by AHP method, and determining the relative weight vector of the evaluation factors; As a preferred implementation, comparing the evaluation factors by the AHP method and determining the relative weight vector of the evaluation factors includes the following steps: S631, compare the evaluation factors in pairs, and establish a judgment matrix based on the comparison results; It should be noted that for every two participating factors, pairwise comparisons are carried out; expert opinions or other reliable methods are used to give a relative importance judgment; commonly used comparison scales include 1 (equal importance), 3 (moderate importance), 5 (obviously important), 7 (very important), and 9 (extremely important), and then these comparison results are adjusted as needed and filled into the corresponding positions of the judgment matrix.
[0053] S632, using eigenvalue decomposition method to solve the eigenvalues and eigenvectors of the judgment matrix; It should be noted that the eigenvalues and corresponding eigenvectors of the judgment matrix can be solved by mathematical software or programming language.
[0054] S633. Normalize the characteristic vector to obtain the relative weight vector of the evaluation factors.
[0055] It should be noted that the final weight vector is obtained by normalizing this eigenvector (usually by dividing it by the sum of its elements). The normalized eigenvector represents the relative weight of each evaluation factor.
[0056] S64. Based on the relative weight vector of the evaluation factors, the evaluation results of the water absorption and swelling performance of the polymer water-absorbing material are calculated.
[0057] As a preferred embodiment, based on the relative weight vector of the evaluation factors, calculating the water absorption and swelling performance evaluation result of the polymer water-absorbing material includes the following steps: S641. Calculate the weighted score of each participating factor by weighted average method according to the relative weight vector of the participating factors; It should be noted that for each participating factor, a score is set (the score range is generally 0 to 1). For each participating factor, its weighted score can be calculated using the following formula: Weighted score = relative weight × factor score. The weighted scores of all participating factors are added together to obtain the final weighted score.
[0058] S642. Calculate the water absorption and swelling performance evaluation results of the polymer water-absorbing material using a numerical calculation method based on the weighted scores of each evaluation factor; It should be noted that, first, a mathematical model is determined to describe the relationship between the water absorption and expansion performance and each participating factor. A mathematical equation describing the water absorption and expansion performance is established based on the determined mathematical model. The equation should include the weighted scores of each participating factor, reflecting the influence of each factor on the water absorption and expansion performance. The weighted scores of each participating factor are then substituted into the established mathematical model, and numerical calculations are performed to obtain the evaluation results of the water absorption and expansion performance of the polymer water-absorbing material. The results of the numerical calculations are interpreted to understand the contribution of each participating factor to the water absorption and expansion performance, which helps to identify key factors and provide directions for improvement.
[0059] S643. Based on the evaluation results, the composition of the polymer-based material and the water-absorbing additive is improved and the water absorption and swelling properties of the polymer water-absorbing material are optimized.
[0060] Specifically, according to the evaluation results, the ratio of polymer-based materials to water-absorbing additives is adjusted, and the type or content of polymer-based materials is changed by increasing or decreasing the content of water-absorbing additives to optimize water absorption and expansion performance. Alternatively, new polymer-based materials or water-absorbing additives may be introduced, which may have better performance and help improve water absorption and expansion performance.
[0061] Specifically, the present invention determines the water absorption density by measuring the mass and volume after water absorption, uses the AHP method for weight allocation and comprehensive scoring, ensures that the evaluation process is scientific and objective, and can comprehensively consider the influence of various factors, and the judgment matrix established by pairwise comparison helps to quantify the relative importance of the participating factors. The eigenvalue decomposition method and the normalization of the eigenvector provide a mathematically reasonable weight vector for the participating factors, ensures that the decision-making process has a solid mathematical foundation, and not only provides a comprehensive, scientific and accurate evaluation framework, but also promotes the decision-making process based on data and analysis, which is conducive to the continuous improvement and optimization of polymer water-absorbing materials.
[0062] like Figure 2 As shown, the present invention also provides a system for detecting water absorption and swelling of polymer water-absorbing materials, the system for detecting water absorption and swelling of polymer water-absorbing materials comprises: a material preparation module 1, an initial data scanning module 2, a water absorption and swelling processing module 3, a final data scanning module 4, a swelling ratio analysis module 5 and a swelling property evaluation module 6, and the material preparation module 1, the initial data scanning module 2, the water absorption and swelling processing module 3, the final data scanning module 4, the swelling ratio analysis module 5 and the swelling property evaluation module 6 are connected in sequence; Material preparation module 1, used for preparing polymer water-absorbing materials based on polymer-based materials and water-absorbing additives; The initial data scanning module 2 is used to perform three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; The water absorption and swelling treatment module 3 is used to immerse the polymer water-absorbing material in water for water absorption and swelling treatment, and calculate the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material; The final data scanning module 4 is used to perform three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain the final three-dimensional point cloud data; An expansion rate analysis module 5 is used to analyze the expansion rate of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data; The expansion evaluation module 6 is used to evaluate the water absorption and expansion of the polymer water absorbent material according to the water absorption rate and expansion rate of the polymer water absorbent material.
[0063] In summary, with the help of the above technical solutions of the present invention, the present invention can very accurately evaluate the water absorption rate and expansion rate of polymer water-absorbing materials by combining weight measurement and three-dimensional laser scanning technology. Three-dimensional scanning provides a detailed view of the volume change of the material before and after water absorption, while weight measurement provides accurate data on water absorption. The combination of the two data can provide a comprehensive understanding of the material behavior, so that the behavior of polymer water-absorbing materials can be studied more deeply, thereby promoting the development of new materials and the improvement of existing materials; the present invention can remove noise and irrelevant data from the original point cloud through preprocessing and contour extraction, and extract key information for analysis. Coordinate transformation and point cloud slicing can simplify the three-dimensional shape into a series of two-dimensional slices, making the problem easier to handle. At the same time, by slicing in the local coordinate system, the details of the shape can be more easily captured. The use of geometric feature point extraction and curve fitting technology can be extracted from the point cloud data. The precise shape contour can be extracted from the data to provide a basis for subsequent volume calculation. The volume calculation using the grid algorithm can simplify the problem by decomposing complex shapes into simple small units, improve calculation efficiency, and provide detailed and comprehensive data support for the research and application of polymer water-absorbing materials. The present invention determines the water absorption density by measuring the mass and volume after water absorption, and uses the AHP method for weight allocation and comprehensive scoring to ensure that the evaluation process is scientific and objective, and can comprehensively consider the influence of various factors. The judgment matrix established by pairwise comparison helps to quantify the relative importance of the participating factors. The eigenvalue decomposition method and the normalization of the eigenvector provide a mathematically reasonable weight vector for the participating factors, ensuring that the decision-making process has a solid mathematical foundation. It not only provides a comprehensive, scientific and precise evaluation framework, but also promotes the decision-making process based on data and analysis, which is conducive to the continuous improvement and optimization of polymer water-absorbing materials.
[0064] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) containing computer-usable program code.
[0065] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for detecting water absorption and swelling of a polymer water-absorbing material, characterized in that: The method for detecting water absorption and swelling of a polymer water-absorbing material comprises the following steps: S1. Preparing a polymer water-absorbing material based on a polymer-based material and a water-absorbing additive; S2, performing three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; S3, immersing the polymer water-absorbing material in water for water absorption and swelling treatment, and calculating the water absorption rate of the polymer water-absorbing material according to the weight before and after the polymer water-absorbing material; S4, performing three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain final three-dimensional point cloud data; S5. Analyze the expansion rate of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data; S6. Evaluate the water absorption and expansion properties of the polymer water absorbent material based on its water absorption rate and expansion rate.
2. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 1, characterized in that: The method of immersing the polymer water-absorbing material in water for water absorption and swelling, and calculating the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material comprises the following steps: S31, measuring the initial weight of the prepared polymer water-absorbing material before water absorption; S32, placing the prepared polymer water-absorbing material into a preset water tank for soaking; S33, after reaching the preset soaking time, taking out the polymer water-absorbing material from the water tank; S34, measuring the weight of the polymer water-absorbing material after absorbing water after the immersion, to obtain a final weight; S35. Calculate the water absorption rate of the polymer water-absorbing material according to the initial weight and the final weight.
3. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 1, characterized in that: The expansion rate analysis of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data comprises the following steps: S51, preprocessing the initial three-dimensional point cloud data and the final three-dimensional point cloud data respectively; S52, respectively extracting the contour of the polymer water-absorbing material from the preprocessed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial contour and a final contour; S53, based on the initial contour and the final contour, using a grid algorithm to calculate the volume of the polymer water-absorbing material before and after water absorption and expansion; S54. Calculate the expansion rate of the polymer water-absorbing material based on the volume of the polymer water-absorbing material before and after the water absorption and expansion.
4. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 3, characterized in that: The steps of extracting the contour of the polymer water-absorbing material from the pre-processed initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain the initial contour and the final contour include the following steps: S521, based on the point cloud slicing algorithm, respectively perform point cloud slicing on the initial three-dimensional point cloud data and the final three-dimensional point cloud data to obtain an initial sheet point cloud and a final sheet point cloud; S522, extracting contour feature points from the initial sheet point cloud and the final sheet point cloud respectively by using a geometric feature point extraction algorithm, wherein the contour feature points include edge points and inflection points; S523, performing curve fitting on the contour feature points of the initial sheet point cloud and the final sheet point cloud respectively by using the least square method; S524, integrating the fitted curves to construct the initial profile and final profile of the polymer water-absorbing material.
5. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 4, characterized in that: The point cloud slicing algorithm is based on which the initial three-dimensional point cloud data and the final three-dimensional point cloud data are sliced to obtain the initial sheet point cloud and the final sheet point cloud, respectively, and the steps include: S5211, respectively perform coordinate transformation on the initial three-dimensional point cloud data and the final three-dimensional point cloud data, and transform the initial three-dimensional point cloud data and the final three-dimensional point cloud data to a direction in which the center line is parallel to the positive direction of the z-axis and the bottom surface is parallel to the xoy plane; S5212, establishing a local coordinate system at any data point of the initial three-dimensional point cloud data and the final three-dimensional point cloud data, and setting the positive direction of the x-axis as the direction of the slice; S5213, respectively obtaining the maximum value and the minimum value of the initial three-dimensional point cloud data and the final three-dimensional point cloud data in the x-axis direction; S5214, respectively dividing the initial three-dimensional point cloud data and the final three-dimensional point cloud data into m equally spaced slices in the x-axis direction, generating m groups of projection planes in the same direction as the x-axis; S5215. A plane perpendicular to the slicing direction is used as a reference plane, and the initial three-dimensional point cloud data and the final three-dimensional point cloud data are projected onto the reference plane to obtain an initial sheet point cloud and a final sheet point cloud.
6. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 3, characterized in that: The method of calculating the volume of the polymer water-absorbing material before and after water absorption and expansion using a grid algorithm based on the initial contour and the final contour comprises the following steps: S531, placing the initial outline and the final outline on the same plane, and establishing a grid; S532, in the grid, for each square of the initial outline and the final outline, using interpolation method to solve the elevation value of each vertex; S533, calculating the volume of each square according to the obtained elevation value; S534, respectively accumulating the volume of each square in the initial outline and the final outline to obtain the volume of the polymer water-absorbing material before and after water absorption and expansion, and using it as the initial state volume and the final state volume.
7. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 1, characterized in that: The method of evaluating the water absorption and expansion property of the polymer water-absorbing material according to the water absorption rate and expansion rate of the polymer water-absorbing material comprises the following steps: S61, determining the water absorption density of the polymer water absorbent material according to the mass and volume of the polymer water absorbent material after absorbing water; S62. The water absorption rate, expansion rate and water absorption density of polymer water-absorbing materials are used as evaluation factors and a hierarchical structure model is established; S63, comparing the evaluation factors by AHP method, and determining the relative weight vector of the evaluation factors; S64. Based on the relative weight vector of the evaluation factors, the evaluation results of the water absorption and swelling performance of the polymer water-absorbing material are calculated.
8. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 7, characterized in that: The method of comparing the evaluation factors by the AHP method and determining the relative weight vector of the evaluation factors includes the following steps: S631, compare the evaluation factors in pairs, and establish a judgment matrix based on the comparison results; S632, using eigenvalue decomposition method to solve the eigenvalues and eigenvectors of the judgment matrix; S633. Normalize the characteristic vector to obtain the relative weight vector of the evaluation factors.
9. A method for detecting water absorption and swelling of polymer water-absorbing materials according to claim 7, characterized in that: The method of calculating the water absorption and swelling performance evaluation result of the polymer water-absorbing material based on the relative weight vector of the evaluation factors comprises the following steps: S641. Calculate the weighted score of each participating factor by weighted average method according to the relative weight vector of the participating factors; S642. Calculate the water absorption and swelling performance evaluation results of the polymer water-absorbing material using a numerical calculation method based on the weighted scores of each evaluation factor; S643. Based on the evaluation results, the composition of the polymer-based material and the water-absorbing additive is improved and the water absorption and swelling properties of the polymer water-absorbing material are optimized.
10. A system for detecting water swelling of a polymer water-absorbing material, used to implement the method for detecting water swelling of a polymer water-absorbing material according to any one of claims 1 to 9, characterized in that: The system for detecting water absorption and swelling of polymer water-absorbing materials comprises: a material preparation module, an initial data scanning module, a water absorption and swelling processing module, a final data scanning module, a swelling rate analysis module and a swelling property evaluation module, and the material preparation module, the initial data scanning module, the water absorption and swelling processing module, the final data scanning module, the swelling rate analysis module and the swelling property evaluation module are connected in sequence; The material preparation module is used to prepare a polymer water-absorbing material based on a polymer-based material and a water-absorbing additive; The initial data scanning module is used to perform three-dimensional scanning on the polymer water-absorbing material by laser scanning technology to obtain initial three-dimensional point cloud data; The water absorption and expansion processing module is used to immerse the polymer water-absorbing material in water for water absorption and expansion processing, and calculate the water absorption rate of the polymer water-absorbing material according to the front and back weights of the polymer water-absorbing material; The final data scanning module is used to perform three-dimensional scanning on the polymer water-absorbing material after water absorption and swelling treatment by laser scanning technology to obtain final three-dimensional point cloud data; The expansion rate analysis module is used to analyze the expansion rate of the polymer water-absorbing material based on the initial three-dimensional point cloud data and the final three-dimensional point cloud data; The expansion evaluation module is used to evaluate the water absorption and expansion of the polymer water absorbent material according to the water absorption rate and expansion rate of the polymer water absorbent material.