Method, system and equipment for detecting moisture content in polylactic acid and medium

Abstract

The invention relates to a method, a system and equipment for detecting the moisture content in polylactic acid and a medium. The method for detecting the moisture content in polylactic acid comprises the following steps: acquiring the mass of a polylactic acid sample to be detected and the mass of a standby alcohol solution containing alkoxide; detecting the content of inorganic base in the alcoholic solution before and after adding the polylactic acid sample to be detected; and determining the moisture content in the polylactic acid based on the content of the inorganic base in the alcoholic solution before and after the polylactic acid sample is added, the mass of the alcoholic solution and the mass of the polylactic acid sample to be detected. The method comprises the following steps: acquiring the mass of a polylactic acid sample to be detected and the mass of an alcohol solution containing alkoxide; detecting the content of inorganic base in the alcoholic solution before and after adding the polylactic acid sample to be detected; the moisture content in the polylactic acid is determined based on the content of the inorganic base in the alcoholic solution before and after the polylactic acid sample is added, the quality of the alcoholic solution and the quality of the polylactic acid sample to be detected, the problems of uneven heating, difficulty in ensuring accuracy and the like are avoided, and the detection accuracy is further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of detection, and particularly relates to a method, a system, a device and a medium for detecting the water content in polylactic acid. Background Art

[0002] Polylactic acid (PLA) is a thermoplastic aliphatic polyester polymer material. Its raw materials are derived from bio-based sources, and after its products complete their usage cycles, they can be completely degraded into water and carbon dioxide under certain conditions, which are fixed by plant photosynthesis to form a carbon cycle, and it is an important way for carbon emission reduction. The biggest feature of polylactic acid is its degradability, but the degradability also brings new problems to polylactic acid. Excellent degradability has relatively high requirements for the water content of polylactic acid raw materials, products and their processing processes, and the water content of polylactic acid needs to be paid special attention to during production, storage and processing into products.

[0003] The most commonly used method for analyzing the water content of polylactic acid is the drying method. In this method, a certain amount of sample is placed in an oven and dried (usually at 105 - 110 °C) to a constant weight. The water in the sample will vaporize due to high temperature, resulting in the loss of the sample mass. Then, the water content in the sample is calculated based on the mass change of the sample before and after drying. However, the time required to measure the water content using this method is relatively long, about 5 - 6 h, and due to reasons such as the positions of the heating rod and the thermocouple, the heating space in the oven is uneven, resulting in large errors in the detection results. To solve the problems of long detection time and uneven heating in the traditional oven method, a rapid moisture analyzer has been developed. The rapid moisture analyzer is internally equipped with a ring-shaped halogen heater to ensure that the sample is evenly heated during the high-temperature test, so that the surface of the sample is not easily damaged and can be quickly dried. During the drying process, the moisture analyzer continuously measures and immediately displays the water content lost by the sample. After the drying program is completed, the finally measured water content value is locked and displayed. Compared with the traditional oven heating method, its detection results have good consistency, good result repeatability, and the detection efficiency is much higher than that of the oven method. It is commonly used in the production and test processes of industries such as plastics, rubber, chemical engineering, medicine, and food. The range of water measured by the rapid moisture analyzer is usually 0.01 wt% - 100 wt%, and the readability of the result is 0.01%. Compared with other plastic slices, polylactic acid (PLA) slices are more sensitive to water and have more stringent requirements for the water content, usually at the ppm (parts per million) level. In addition to water, PLA slices usually also contain volatile substances such as the polymerization monomer lactide. When using the drying method to measure the water content of PLA, these volatile substances will also interfere with the measurement results. Obviously, the principle of measuring water by the rapid moisture analyzer is still the drying method, and the result is calculated based on the mass difference of the sample before and after drying, resulting in low measurement accuracy. The rapid moisture analyzer based on the drying method is not suitable for the routine measurement of the water content of PLA slices.

[0004] The Coulometric method is a relatively accurate method for measuring moisture content, with high measurement efficiency and strong result repeatability. Its principle is that moisture undergoes a quantitative reaction with Karl Fischer reagent (iodine, sulfur dioxide, alcohols, and organic bases). If this method is used to measure the moisture content in PLA chips, a Karl Fischer furnace needs to be equipped. A certain amount of sample is placed in a headspace vial, and the sample is heated. The evaporated moisture is carried into the Karl Fischer titration cell by a high-purity carrier gas that has been dried and dehydrated. The moisture in the sample reacts with the Karl Fischer reagent in the titration cell, and the reaction formula is:

[0005] H2O + I2 + [RNH]SO3CH3 + 2RN → [RNH]SO4CH3 + 2[RNH]I

[0006] The consumed elementary iodine is generated by electrolysis at the anode, enabling the redox reaction to continue until all the moisture is exhausted. According to Faraday's law of electrolysis, the iodine generated by electrolysis is directly proportional to the amount of electricity consumed by electrolysis, thereby calculating the moisture content in the sample. The electrode reaction formula is:

[0007] Anode: 2I - - 2e - → I2;

[0008] Cathode: I2 + 2e - → 2I - ,2H + + 2e - → H2↑.

[0009] However, the principle of this method for measuring the moisture content in PLA chips still belongs to the drying method, and it cannot ensure that all the moisture in the polymer is brought out by heating, making it difficult to guarantee the accuracy of the measurement results. Summary of the Invention

[0010] In view of this, the present invention provides a method, system, device, and medium for detecting the moisture content in polylactic acid.

[0011] To achieve the above solution, the technical solution of the present invention is as follows:

[0012] In the first aspect, the present application provides a method for detecting the moisture content in polylactic acid, including the following steps:

[0013] Obtain the mass of the polylactic acid sample to be detected and the mass of the alcohol solution containing alkoxide, where the alkoxide contains a metal element, and the inorganic base is the inorganic base corresponding to the metal element;

[0014] Detect the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected;

[0015] Determine the moisture content in the polylactic acid based on the content of the inorganic base in the alcohol solution, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected before and after adding the polylactic acid sample.

[0016] Optionally, the alcohol is selected from alcohol substances with 1-4 carbon atoms.

[0017] Optionally, the metal element is selected from at least one of lithium, sodium, and potassium.

[0018] Optionally, the mass ratio of the alcohol salt to the polylactic acid sample to be detected is 1.1-1.5:1, preferably 1.2-1.5:1.

[0019] Optionally, in the alcohol solution, the concentration of the alcohol salt is 10wt%-50wt%, preferably 10wt%-20wt%.

[0020] Optionally, the Karl Fischer method is used to detect the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected.

[0021] Optionally, determining the moisture content in the polylactic acid includes:

[0022] Based on the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, and the inorganic base is the inorganic base corresponding to the salt in the alcohol salt;

[0023] Determine the moisture content in the polylactic acid according to the content of the inorganic base, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected.

[0024] Optionally, determining the moisture content in the polylactic acid includes:

[0025] Determine the molar amount of water according to the mass of the alcohol solution and the content of the inorganic base therein;

[0026] Determine the moisture content in the polylactic acid according to the molar amount of water and the mass of the polylactic acid sample to be detected.

[0027] In a second aspect, the present application also provides a detection system for the moisture content in polylactic acid, including:

[0028] A mass acquisition module configured to acquire the mass of the polylactic acid sample to be detected and the mass of the alcohol solution containing the alcohol salt to be used, and the alcohol salt contains a metal element;

[0029] A detection module configured to detect the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, and the inorganic base is the inorganic base corresponding to the metal element;

[0030] A determination module, configured to determine the water content in polylactic acid based on the content of inorganic base in the alcohol solution, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected before and after adding the polylactic acid sample.

[0031] In a third aspect, the present application further provides an electronic device, which includes:

[0032] One or more processors;

[0033] A storage device for storing one or more programs, which, when executed by the one or more processors, cause the electronic device to implement the method for detecting the water content in polylactic acid as described above.

[0034] In a fourth aspect, the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer is caused to execute the method for detecting the water content in polylactic acid as described above.

[0035] As described above, the method, system, device, and medium for detecting the water content in polylactic acid of the present invention have the following beneficial effects:

[0036] The present application obtains the mass of the polylactic acid sample to be detected and the mass of the alcohol solution containing alkoxide; detects the content of inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected; and determines the water content in the polylactic acid based on the content of inorganic base in the alcohol solution, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected before and after adding the polylactic acid sample, avoiding technical problems such as uneven heating and difficulty in ensuring accuracy in the prior art, and thus improving the accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. In the drawings:

[0038] Figure 1 is a flowchart of the method for detecting the water content in polylactic acid shown in an exemplary embodiment of the present application;

[0039] Figure 2 is Figure 1 a flowchart of step S130 in the shown embodiment in an exemplary embodiment;

[0040] Figure 3 is Figure 2Flow chart of step S220 in the illustrated embodiment in an exemplary embodiment;

[0041] Figure 4 Block diagram of a detection system for water content in polylactic acid shown in an exemplary embodiment of the present application;

[0042] Figure 5 Schematic structural diagram of a computer system of an electronic device suitable for implementing the embodiments of the present application. Detailed implementation manners

[0043] The present invention will be further described below through specific specific examples. It should be noted that the specific material ratios, process conditions, results, etc. described in the embodiments of the present invention are only used to illustrate the present invention, and the protection scope of the present invention cannot be limited thereby. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

[0044] The present invention will be described in detail below through specific exemplary embodiments. Similarly, it should be understood that the following embodiments are only used to specifically illustrate the present invention, and cannot be understood as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention all belong to the protection scope of the present invention. The specific process parameters and the like in the following examples are also only an example within a suitable range, that is, those skilled in the art can make selections within a suitable range according to the description herein, rather than being limited to the specific values in the following examples.

[0045] Please refer to Figure 1 , Figure 1 Flow chart of a detection method for water content in polylactic acid shown in an exemplary embodiment of the present application.

[0046] As Figure 1 shown, in an exemplary embodiment, the detection method for water content in polylactic acid at least includes steps S110 to S130, which are introduced in detail as follows:

[0047] Step S110. Obtain the mass of the polylactic acid sample to be detected and the mass of the alcohol solution containing alkoxide for use;

[0048] It should be noted that in the present application, the alcohol is selected from alcohol substances with 1 to 4 carbon atoms, the alkoxide contains a metal element, the metal element is selected from at least one of lithium, sodium, and potassium, and in the alcohol solution, the concentration of the alkoxide is 10 wt% - 50 wt%.

[0049] It should be noted that in the present application, the alkoxide contains a metal element,

[0050] Step S120. Obtain the content of inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected;

[0051] It should be noted that in this application, the mass ratio of the alcoholate to the polylactic acid sample to be detected is 1.1 - 1.5:1.

[0052] It should be noted that in this application, the inorganic base is the inorganic base corresponding to the metal element.

[0053] Exemplarily, the Karl Fischer method is used to obtain the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected. In other words, the Karl Fischer method is used to detect the content of the inorganic base in the alcohol solution before adding the polylactic acid sample to be detected and the content of the inorganic base in the alcohol solution after adding the polylactic acid sample to be detected respectively.

[0054] The principle of this application is as follows:

[0055] The alcoholate reacts with polylactic acid to form lactate; the water contained in the polylactic acid reacts with the alcoholate to form an inorganic base. The molar amount of the inorganic base generated by the reaction is the same as the molar amount of the water consumed during the reaction. Therefore, based on the mass difference of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, the molar amount of the inorganic base generated during the reaction, that is, the molar amount of water, can be determined. The reaction process is as follows (taking sodium methoxide as an example);

[0056]

[0057] CH3ONa + H2O → NaOH + CH3OH;

[0058] I2 + 2NaOH → Nal + NalO + H2O;

[0059]

[0060] Step S130. Based on the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected, determine the water content in the polylactic acid. In other words, based on the content of the inorganic base in the alcohol solution before adding the polylactic acid sample, the content of the inorganic base in the alcohol solution after adding the polylactic acid sample, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected, determine the water content in the polylactic acid.

[0061] In the related art, the moisture content is measured based on the drying method and the coulomb method. After the inventor analyzed the above technologies, it was found that the heating space was uneven and the detection result error was large. The rapid moisture analyzer based on the drying method was not suitable for the conventional measurement of the moisture content of PLA chips. When using the coulomb method to measure the moisture content in PLA chips, it was impossible to ensure that all the moisture in the polymer was brought out by heating, and it was difficult to guarantee the accuracy of the measurement results. Therefore, the inventor considered that polylactic acid solids could react with alkoxides and dissolve in alcohols, and all the moisture contained in them was released and reacted with the alkoxides to form inorganic bases and alcohols. By obtaining the mass of the polylactic acid sample to be detected, the mass of the alcohol solution containing alkoxide for use, and the content of the inorganic base; detecting the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected; based on the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected, the moisture content in the polylactic acid was determined, avoiding technical problems such as uneven heating and difficulty in ensuring accuracy in the prior art, and thus improving the detection accuracy.

[0062] Please refer to Figure 2 , Figure 2 is Figure 1 the flowchart of step S130 in the exemplary embodiment shown in

[0063] As Figure 2 shown, in an exemplary embodiment of the present application, the process of determining the moisture content in polylactic acid may include step S210 to step S220, which are introduced in detail as follows:

[0064] In an exemplary embodiment, determining the moisture content in polylactic acid includes:

[0065] S210. Determine the mass difference of the inorganic base based on the mass of the alcohol solution and the content of the inorganic base before and after adding the polylactic acid sample to be detected.

[0066] Exemplarily, the difference obtained by multiplying the content of the inorganic base in the alcohol solution after adding the polylactic acid sample to be detected by the mass of the alcohol solution and subtracting the product of the content of the inorganic base in the alcohol solution before adding the polylactic acid sample to be detected and the mass of the alcohol solution (i.e., the mass difference) is the mass of the inorganic base generated by the reaction of water in the polylactic acid sample with the alkoxide.

[0067] S220. Determine the moisture content in the polylactic acid according to the amount of the inorganic base generated by the reaction of water with the alkoxide and the mass of the polylactic acid sample to be detected.

[0068] Please refer to Figure 3 , Figure 3 is Figure 2 the flowchart of step S220 in the exemplary embodiment shown in

[0069] As Figure 3As shown, in an exemplary embodiment of the present application, the process of determining the water content in polylactic acid may include steps S310 to S320, which are introduced in detail as follows:

[0070] Step S310. Determine the molar amount of water according to the mass difference of the inorganic base and the mass of the alcohol solution.

[0071] Exemplarily, the mass difference of the inorganic base is the amount of the inorganic base generated by the reaction. According to the amount of this inorganic base and the molar mass of this inorganic base (usually known data), the molar amount of the inorganic base generated by the reaction can be determined (the quotient obtained by dividing the mass of the inorganic base by the molar amount of the inorganic base is the molar amount of the inorganic base generated by the reaction). The molar amount of the inorganic base generated by the reaction is the molar amount of water consumed by the reaction, that is, the molar amount of water determined here. Multiplying by the molar mass of water gives the mass of water.

[0072] Step S320. Determine the water content in polylactic acid according to the mass of water and the mass of the polylactic acid sample to be detected.

[0073] Exemplarily, the product of the molar amount of water and the molar mass of water (usually known data) is the mass of water. The ratio of the mass of water to the mass of the polylactic acid sample is the water content in polylactic acid.

[0074] In a specific embodiment, the steps of the method for detecting the water content in polylactic acid are as follows:

[0075] Obtain the mass of the polylactic acid sample to be detected (a standard polylactic acid sample, and the specific preparation steps are: 1) Take a polylactic acid sample and crush it with a pulverizer; 2) Sieve it with a 100-mesh sample sieve, take the sieved polylactic acid powder, and weigh it), and the mass of the methanol solution containing 20 wt% sodium methoxide for use. Weigh the polylactic acid sample to be detected to obtain the mass of the polylactic acid sample to be detected.

[0076] Use the Karl Fischer method to detect the content of sodium hydroxide in the above methanol solution before and after adding the polylactic acid sample to be detected, calculate the mass of the contained sodium hydroxide, and the mass ratio of the polylactic acid sample to sodium methoxide is 1:1.5.

[0077] Based on the content of sodium hydroxide in the methanol solution before and after adding the polylactic acid sample to be detected, determine the mass difference of sodium hydroxide. Specifically, the difference obtained by subtracting the mass of sodium hydroxide in the methanol solution before adding the polylactic acid sample to be detected from the mass of sodium hydroxide in the methanol solution after adding the polylactic acid sample to be detected is the mass difference of sodium hydroxide (the product of the sodium hydroxide content after adding the polylactic acid sample and the mass of the methanol solution minus the product of the sodium hydroxide content before adding the polylactic acid sample and the mass of the sodium methoxide solution, and the obtained value is the mass difference of sodium hydroxide, that is, the mass of sodium hydroxide generated by the reaction of water and sodium methoxide).

[0078] Determine the molar amount of water based on the mass difference and the molar mass of sodium hydroxide. Specifically, based on the mass difference and the molar mass of sodium hydroxide (known data), the molar amount of sodium hydroxide produced by the reaction can be determined. The molar amount of sodium hydroxide produced by the reaction is the molar amount of water consumed by the reaction, that is, the molar amount of water determined here;

[0079] Determine the water content in polylactic acid based on the molar amount of water and the mass of the polylactic acid sample to be detected. Specifically, the product of the molar amount of water and the amount of substance of water (known data) is the mass of water. The ratio of the mass of water to the mass of the polylactic acid sample is the water content in polylactic acid. Here, 5 mg and 10 mg are respectively selected as two spiking levels for detection. Taking 5 mg as an example, the specific preparation steps are as follows: ① Weigh 10.0000 g of the pulverized polylactic acid sample, add 5 μg of water to the polylactic acid sample, dissolve and dilute it to 100 ml with methanol-sodium methoxide, and absorb 10.00 ml of the spiked sample. The mass of water contained in the sample is m1 = direct measurement value × 10; ② At the same time, take this 10.0000 g sample for a blank experiment, and measure the water content of the blank sample as m0 = direct measurement value × 10. The actually added mass of water m = m1 - m0; ③ At the same time, repeat the parallel water addition experiment 6 times; ④ Calculate the spiking recovery rate of the six experiments and the relative standard deviation of the recovery rate. The results are shown in Tables 1 and 2.

[0080] Table 1 Spiking recovery rate data with a spiking amount of 5 μg

[0081]

[0082] Table 2 Spiking recovery rate data with a spiking amount of 10 μg

[0083]

[0084] As can be seen from Tables 1 and 2, the spiking recovery rate is about 100%, and the relative standard deviation of the spiking recovery rate is less than 0.2%. This result shows that the method of the present application for detecting the water content in polylactic acid has high accuracy, high precision and good stability.

[0085] Figure 4 It is a block diagram of a water content detection system M400 for polylactic acid shown in an exemplary embodiment of the present application.

[0086] As Figure 5 shown, the exemplary water content detection system M400 for polylactic acid includes:

[0087] A mass acquisition module M410 configured to acquire the mass of the polylactic acid sample to be detected and the mass of the alcohol solution containing alkoxide for use;

[0088] It should be noted that in the present application, the metal alkoxide contains a metal element;

[0089] The detection module M420 is configured to detect the content of inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected;

[0090] It should be noted that in the present application, the inorganic base is the inorganic base corresponding to the metal element;

[0091] The determination module M430 is configured to determine the water content in the polylactic acid based on the content of the inorganic base in the alcohol solution, the mass of the alcohol solution, and the mass of the polylactic acid sample to be detected before and after adding the polylactic acid sample.

[0092] It should be noted that the detection system for the water content in polylactic acid provided in the above embodiments and the detection method for the water content in polylactic acid provided in the above embodiments belong to the same concept. The specific manners in which each module and unit perform operations have been described in detail in the method embodiments and will not be elaborated herein. In practical applications, the detection system for the water content in polylactic acid provided in the above embodiments can, according to needs, allocate the above functions to different functional modules, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above. This is not limited herein either.

[0093] An embodiment of the present application further provides an electronic device, including: one or more processors; a storage device for storing one or more programs, which when executed by the one or more processors, cause the electronic device to implement the detection method for the water content in polylactic acid provided in each of the above embodiments.

[0094] Figure 5 The structural schematic diagram of a computer system of an electronic device suitable for implementing the embodiments of the present application is shown. It should be noted that Figure 5 The computer system 500 of the electronic device shown is only an example and should not impose any limitation on the functions and usage scope of the embodiments of the present application.

[0095] As Figure 5As shown, the computer system 500 includes a Central Processing Unit (CPU) 501, which can perform various appropriate actions and processes according to a program stored in a Read-Only Memory (ROM) 502 or a program loaded from a storage section 508 into a Random Access Memory (RAM) 503, such as executing the method described in the above embodiments. In the RAM 503, various programs and data required for system operations are also stored. The CPU 501, ROM 502, and RAM 503 are connected to each other via a bus 504. An Input / Output (I / O) interface 505 is also connected to the bus 504.

[0096] The following components are connected to the I / O interface 505: an input section 506 including a keyboard, a mouse, etc.; an output section 507 including, for example, a Cathode Ray Tube (CRT), a Liquid Crystal Display (LCD), etc., and a speaker, etc.; a storage section 508 including a hard disk, etc.; and a communication section 509 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 509 performs communication processing via a network such as the Internet. A drive 510 is also connected to the I / O interface 505 as needed. A removable medium 511, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 510 as needed so that a computer program read from it can be installed into the storage section 508 as needed.

[0097] Specifically, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 509, and / or installed from the removable medium 511. When the computer program is executed by a Central Processing Unit (CPU) 501, various functions defined in the system of the present application are executed.

[0098] It should be noted that the computer-readable medium shown in the embodiments of the present application may be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as a part of a carrier wave, which carries a computer-readable computer program. Such a propagated data signal may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium may be transmitted by any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0099] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, and the combination of blocks in the block diagram or flowchart, may be implemented by a dedicated hardware-based system for performing the specified functions or operations, or may be implemented by a combination of dedicated hardware and computer instructions.

[0100] The units involved in the embodiments described in this application can be implemented in software or in hardware, and the described units can also be provided in a processor. Among them, the names of these units do not constitute a limitation to the unit itself in some cases.

[0101] Another aspect of this application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor of the computer, the computer is caused to execute the method for detecting the moisture content in polylactic acid as described above. The computer-readable storage medium can be included in the electronic device described in the above embodiments, or can exist alone without being assembled into the electronic device.

[0102] Another aspect of this application also provides a computer program product or a computer program. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method for detecting the moisture content in polylactic acid provided in the above various embodiments.

[0103] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for detecting the water content in polylactic acid, characterized in that, The following steps are involved: Obtaining the mass of the polylactic acid sample to be tested and the mass of the alcohol solution containing alkoxide to be used, wherein the alkoxide contains a metal element; Detecting the content of the inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected, wherein the inorganic base is the inorganic base corresponding to the metal element; The moisture content in the polylactic acid is determined based on the content of the inorganic base in the alcohol solution before and after the polylactic acid sample is added, the mass of the alcohol solution and the mass of the polylactic acid sample to be tested.

2. The method for detecting the water content in polylactic acid according to claim 1, wherein The alcohol is selected from alcohols having 1 to 4 carbon atoms.

3. The method for detecting the water content in polylactic acid according to claim 1, wherein The metal element is selected from at least one of lithium, sodium and potassium.

4. The method for detecting the moisture content in polylactic acid according to claim 1, characterized in that, In the alcohol solution, the concentration of the alkoxide is 10wt%-50wt%; And / or, the mass ratio of the alkoxide to the polylactic acid sample to be detected is 1.1-1.5:

1.

5. The method for detecting the water content in polylactic acid according to claim 1, characterized in that, The Karl-Fischer method is used to detect the content of inorganic base in the alcohol solution before and after adding the polylactic acid sample to be detected.

6. The method for detecting the water content in polylactic acid according to claim 1, characterized in that, Determining the moisture content in the polylactic acid comprises: Based on the content of inorganic base in the alcohol solution before and after the polylactic acid sample to be detected is added, the water content in the polylactic acid is determined according to the content of inorganic base, the mass of the alcohol solution and the mass of the polylactic acid sample to be detected.

7. The method for detecting the water content in polylactic acid according to claim 1, wherein, Determining the moisture content in the polylactic acid comprises: Determining the molar amount of water according to the content and the mass of the alcohol solution; The water content in the polylactic acid is determined according to the molar amount of water and the mass of the polylactic acid sample to be tested.

8. A detection system for the water content in polylactic acid, characterized in that, include: A mass acquisition module is configured to acquire the mass of the polylactic acid sample to be tested and the mass of the alcohol solution containing alkoxide to be used, wherein the alkoxide contains metal elements; A detection module is configured to detect the content of the inorganic base in the alcohol solution before and after the polylactic acid sample to be detected is added, wherein the inorganic base is the inorganic base corresponding to the metal element; The determination module is configured to determine the water content in the polylactic acid based on the content of the inorganic base in the alcohol solution before and after the polylactic acid sample is added, the mass of the alcohol solution and the mass of the polylactic acid sample to be tested.

9. An electronic device, characterized in that, The electronic device comprises: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the electronic device to implement the method for detecting the moisture content in polylactic acid as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, A computer program is stored thereon, and when the computer program is executed by a processor of a computer, the computer is enabled to execute the method for detecting the moisture content in polylactic acid as described in any one of claims 1 to 7.

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