Device for measuring Young modulus of polybutylene-1

Abstract

The invention discloses a device for measuring Young modulus of polybutylene-1, which belongs to the technical field of Young modulus measurement and has the measurement principle that the average T2 relaxation rate and Young modulus of the polybutylene-1 have good correlation. According to the measuring device, the Young modulus of a series of polybutylene-1 with different structures at different temperatures can be quickly obtained by utilizing the relationship. The method comprises the following steps: respectively measuring a stress-strain curve and a T2 relaxation curve of a polybutylene-1 sample in different states by using a stretching instrument and a low-field solid nuclear magnetic resonance spectrometer, obtaining Young modulus and a corresponding average T2 relaxation rate by using a corresponding program, and obtaining a linear function corresponding to the Young modulus and the average T2 relaxation rate; after the linear function is obtained, the Young modulus does not need to be obtained by repeatedly carrying out stretching detection on a sample through a stretching instrument like a traditional method, only the corresponding T2 relaxation time and phase composition need to be measured through a low-field solid nuclear magnetic resonance spectrometer, and then the Young modulus of polybutylene-1 in different states can be obtained by substituting the relaxation time and the phase composition into the function for calculation.

Description

Technical Field

[0001] This invention belongs to the field of Young's modulus measurement technology, and specifically relates to a device for measuring the Young's modulus of polybutene-1, a polymer material. Background Technology

[0002] Polymer materials are a class of engineering materials with broad application prospects, and their mechanical properties have a significant impact on their strength and reliability. The mechanical properties of polymer materials refer to their macroscopic properties of resisting deformation and fracture under external forces, such as elasticity, plasticity, hardness, and impact resistance. These properties are the main basis for material selection when designing various engineering structures. For polymer materials, deformation performance is one of the important indicators for evaluating their mechanical properties and reliability. Therefore, studying the deformation performance of polymer materials is of great significance for improving their application value. Although polymers are viscoelastic materials, exhibiting time and temperature dependence, some assumptions and theorems in elasticity theory can still be used to discuss the deformation of viscoelastic polymers under small deformations. Within the applicability of Hooke's law, the ratio of uniaxial stress to uniaxial deformation is Young's modulus, a physical quantity that reflects the material's ability to resist elastic deformation and is one of the important bases for material structure design.

[0003] Polybutene-1 (PP-1) possesses outstanding resistance to environmental stress cracking, creep, heat, and chemical corrosion, making it suitable for applications in pipes, films, and cable insulation. Due to its superior performance and high price, it is often referred to as "plastic gold," yet it has not achieved the large-scale industrial production and application seen with polyethylene and polypropylene. The properties of P-1 are largely influenced by its complex polymorphic behavior. Under different crystallization conditions, P-1 can form four different crystal forms: crystal form II, crystal form I, crystal form I', and crystal form III, each with different crystal structures. Crystal form II is a tetrahedral 113 helical structure.

[0004] Quadratic crystal form, with left-handed and right-handed chains appearing in pairs, exhibiting opposite chirality, space group is Crystal form I consists of 3 / 1 helical chains of left-handed (L) and right-handed (R), exhibiting a hexagonal stacked crystal structure with space group I. During the crystallization of polybutene-1 melt, a metastable crystal form II is initially formed. At room temperature, it requires a certain period of time to irreversibly transform from crystal form II to the stable crystal form I, significantly improving the material's structural stability and mechanical properties. With the steady increase in domestic polybutene-1 production and its expanding application scenarios, further research on the structure and mechanical properties of polybutene-1 is urgently needed.

[0005] There are various devices for determining the Young's modulus of polybutene-1. Commonly used measuring devices utilize methods such as tensile testing, beam bending, vibration testing, and internal friction testing. New experimental techniques and methods have also emerged, including those using fiber optic displacement sensors, moiré fringes, eddy current sensors, and wave transmission technology (microwave or ultrasonic). One common method involves applying a constant stress to the sample using a tensile tester, recording the deformation during the tensile process, calculating the strain, and then using the ratio of the strain to obtain the Young's modulus. However, the crystallization temperature and testing temperature of polymer materials significantly affect the Young's modulus. Using traditional tensile testers is problematic because the samples cannot be reused, resulting in the consumption of large amounts of material, and it is also impossible to measure the Young's modulus of brittle samples.

[0006] In order to solve the above-mentioned problems, clarify a reasonable processing technology scheme, ensure product quality, and improve production efficiency, it is necessary to develop a new measuring device. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of the prior art by providing a device for measuring the Young's modulus of polybutene-1. By establishing the correspondence between the relaxation time of polybutene-1 and its Young's modulus, a formula for calculating the Young's modulus can be obtained, thereby quickly obtaining the Young's modulus at any test temperature corresponding to different crystallization temperatures, saving detection time.

[0008] To solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0009] A device for measuring the Young's modulus of polybutene-1 includes a hot press, a pneumatic sample cutter, a heating device, a tensile tester, an NMR instrument, and a storage device, wherein the hot press, the pneumatic sample cutter, the heating device, the tensile tester, the NMR instrument, and the storage device are all connected to a control system.

[0010] The hot press includes a hot press mold, which is used to hot press polybutene-1 and eliminate past thermal history in the process;

[0011] The pneumatic sample cutter includes a cutter, which is used to cut the hot-pressed sample to the size that meets the requirements of the tensile tester.

[0012] The heating device is used to heat treat the sample, and it can adjust the heating temperature to make the sample crystallize isothermally at different temperatures to obtain samples with different lamellar thicknesses.

[0013] The tensile tester can adjust the tensile temperature to perform tensile tests at different temperatures and test its Young's modulus.

[0014] The nuclear magnetic resonance instrument is a low-field solid-state nuclear magnetic resonance instrument;

[0015] The memory contains a computer program capable of performing a measurement method, which includes:

[0016] Step 1: Measure the stress-strain curves of polybutene-1 samples at several different tensile temperatures and different crystallization temperatures using the tensile instrument described in the device, and obtain the Young's modulus E of polybutene-1 at different crystallization temperatures and different tensile temperatures.

[0017] Step 2: Using the nuclear magnetic resonance (NMR) instrument described in the apparatus, detect the T2 relaxation curves of polybutene-1 at the corresponding crystallization temperature and test temperature of the above sample in Step 1. Fit the T2 relaxation curves using Abragamian, Gaussian, and two exponential functions to obtain the T2 relaxation time T2 of the crystalline region. cr And amplitude A(0) cr The T2 relaxation time of the interface int And amplitude A(0) int And the T2 relaxation time of the amorphous region. am1 T2 am2 And amplitude A(0) am1 A(0) am2 ;Utilizing the relaxation time T2 of each phase region cr T2 int T2 am1 T2 am2 and amplitude A(0) cr A(0) int A(0) am1 A(0) am2 The average relaxation rate of the sample was calculated as 1 / T2. ave .

[0018] Step 3: Combine the Young's modulus E obtained in Step 1 with the average relaxation rate of the sample 1 / T2 ave Perform a fitting operation to obtain the corresponding fitting function;

[0019] Step 4: Use the nuclear magnetic resonance instrument described in the device to detect the relaxation curves of polybutene-1 samples at different crystallization temperatures and different test temperatures. new The T2 relaxation curve was fitted using the Abragaimian function, the Gaussian function, and two exponential functions. new To obtain the T2 relaxation time T2 of the new crystal region cr-new And amplitude A(0) cr-new The T2 relaxation time of the interface int-new And amplitude A(0) int-new T2 relaxation time of amorphous region am1-new and T2 am2-new And amplitude A(0) am1-new A(0) am2-new;Utilizing the relaxation time T2 of each phase region cr-new T2 int-new T2 am1-new T2 am2-new and amplitude A(0) cr-new A(0) int-new A(0) am1-new A(0) am2-new The average relaxation rate of the sample was calculated as 1 / T2. ave-new ;

[0020] Step 5: Calculate the average relaxation rate 1 / T2 obtained in Step 4. ave-new By substituting the values ​​into the fitting function from step three, we can obtain the Young's modulus E of polybutene-1 at any test temperature corresponding to different crystallization temperatures. new Step three calculates 1 / T2. ave The method is as follows:

[0021] 1 / T2 ave =f cr / T2 cr +f int / T2 int +f am1 / T2 am1 +f am2 / T2 am2 The content of crystal regions f cr =A(0) cr / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], interface content f int =A(0) int / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 Amorphous region content f am1 =A(0) am1 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], f am2 =A(0) am2 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], i.e. f cr +f int +f am1 +f am2=1. In step three, a linear function is used to fit 1 / T2. ave The relationship between Young's modulus and this linear function is expressed as: Young's modulus E = a × (1 / T²) ave )+b.

[0022] Step 5 yields 1 / T2 ave-new The method is as follows:

[0023] 1 / T2 ave-new =f cr-new / T2 cr-new +f int-new / T2 int-new +f am1-new / T2 am1-new +f am2-new / T2 am2-new The content of crystal regions f cr-new =A(0) cr-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], interface content f int-new =A(0) int-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new Amorphous region content f am1-new =A(0) am1-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], f am2-new =A(0) am2-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], i.e. f cr-new +f int-new +f am1-new +f am2-new =1.

[0024] The calculation method in step five also includes taking 1 / T2 ave-new Substituting into step three, E = a × (1 / T2) ave )+b, find E new =a×(1 / T2) ave-new )+b.

[0025] The stretching apparatus includes a heating stage, which is used to change the stretching temperature.

[0026] The resonance frequency of the nuclear magnetic resonance instrument is 19.65MHz.

[0027] The beneficial effects of this invention are:

[0028] (1) The present invention discloses a device for measuring the Young's modulus of polybutene-1. The measurement principle is that the present application has creatively discovered that there is a corresponding relationship between the average T2 relaxation rate of polybutene-1 and its Young's modulus. The corresponding linear relationship is obtained by measuring the Young's modulus and T2 relaxation time of polybutene-1 samples under different conditions by a tensile tester and storing it. After obtaining the linear relationship, it is not necessary to obtain the Young's modulus by traditional methods such as sample preparation and stretching. It is only necessary to use a low-field solid-state nuclear magnetic resonance spectrometer to measure the corresponding T2 relaxation time and phase composition, and then substitute it into the function to calculate the Young's modulus of polybutene-1 under different conditions. It is not necessary to repeatedly prepare test samples and use a tensile tester to perform tensile testing.

[0029] (2) Compared with traditional testing devices, this device can achieve non-destructive testing of samples, thereby enabling the repeated recycling of samples. At the same time, this device can also achieve rapid testing of a large number of samples, saving testing time. In addition, this device can realize the connection between the macroscopic mechanical properties and microstructure of polybutene-1 material, which has great practical significance for computer modeling of the mechanical behavior of polybutene-1 and prediction of its properties. Attached Figure Description

[0030] Figure 1 It is the average relaxation rate 1 / T2 in Example 1. ave A schematic diagram of the dependence curve on Young's modulus. Detailed Implementation

[0031] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0032] This invention provides a device for measuring the Young's modulus of polybutene-1.

[0033] A device for measuring the Young's modulus of polybutene-1 includes a hot press, a pneumatic sample cutter, a heating device, a tensile tester, an NMR instrument, and a storage device. The NMR instrument and the storage device are both connected to a control system, and the storage device stores a computer program capable of performing the following measurement method.

[0034] The memory contains a computer program capable of performing the following measurement methods;

[0035] The hot press includes a hot press mold, which is used to hot press polybutene-1 and eliminate past thermal history in the process;

[0036] The pneumatic sample cutter includes a cutter, which is used to cut the hot-pressed sample to the size that meets the requirements of the tensile tester.

[0037] The heating device is used to heat treat the sample, and it can adjust the heating temperature to make the sample crystallize isothermally at different temperatures to obtain samples with different lamellar thicknesses.

[0038] The tensile tester includes a hot stage, which can adjust the temperature of the hot stage to change the temperature of the polybutene-1 sample, thereby enabling tensile tests to be performed at different temperatures and testing its Young's modulus.

[0039] The nuclear magnetic resonance instrument is a low-field solid-state nuclear magnetic resonance instrument with a resonance frequency of 19.65 MHz;

[0040] The measurement method includes the following steps:

[0041] Step 1: Measure the stress-strain curves of polybutene-1 samples at several different tensile temperatures and different crystallization temperatures using the tensile instrument described in the device, and obtain the Young's modulus E of polybutene-1 at different crystallization temperatures and different tensile temperatures.

[0042] Step 2: Using the nuclear magnetic resonance (NMR) instrument described in the apparatus, detect the T2 relaxation curves of polybutene-1 at the corresponding crystallization temperature and test temperature of the above sample in Step 1. Fit the T2 relaxation curves using Abragamian, Gaussian, and two exponential functions to obtain the T2 relaxation time T2 of the crystalline region. cr And amplitude A(0) cr The T2 relaxation time of the interface int And amplitude A(0) int And the T2 relaxation time of the amorphous region. am1 T2 am2 And amplitude A(0) am1 A(0) am2 ;Utilizing the relaxation time T2 of each phase region cr T2 int T2 am1 T2 am2 and amplitude A(0) cr A(0) int A(0) am1 A(0) am2 The average relaxation rate of the sample was calculated as 1 / T2. ave .

[0043] Step 3: Using a computer program, compare the Young's modulus E obtained in Step 1 with the average relaxation rate 1 / T2 of the sample. ave Perform a fitting operation to obtain the corresponding fitting function;

[0044] Step 4: Use the nuclear magnetic resonance instrument described in the device to detect the relaxation curves of polybutene-1 samples at different crystallization temperatures and different test temperatures. new The T2 relaxation curve was fitted using the Abragaimian function, the Gaussian function, and two exponential functions. new To obtain the T2 relaxation time T2 of the new crystal region cr-new And amplitude A(0) cr-new The T2 relaxation time of the interface int-new And amplitude A(0) int-new T2 relaxation time of amorphous region am1-new and T2 am2-new And amplitude A(0) am1-new A(0) am2-new ;Utilizing the relaxation time T2 of each phase region cr-new T2 int-new T2 am1-new T2 am2-new and amplitude A(0) cr-new A(0) int-new A(0) am1-new A(0) am2-new The average relaxation rate of the sample was calculated as 1 / T2. ave-new .

[0045] Step 5: Calculate the average relaxation rate 1 / T2 obtained in Step 4. ave-new By substituting the values ​​into the fitting function from step three, we can obtain the Young's modulus E of polybutene-1 at any test temperature corresponding to different crystallization temperatures. new .

[0046] Furthermore, in step three, 1 / T2 is calculated. ave The method is as follows:

[0047] 1 / T2 ave =f cr / T2 cr +f int / T2 int +f am1 / T2 am1 +f am2 / T2 am2 The content of crystal regions f cr =A(0) cr / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], interface content f int =A(0) int / [A(0) cr +A(0)int +A(0) am1 +A(0) am2 Amorphous region content f am1 =A(0) am1 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], f am2 =A(0) am2 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], i.e. f cr +f int +f am1 +f am2 =1.

[0048] Furthermore, in step three, a linear function is used to fit 1 / T2. ave The relationship between Young's modulus and this linear function is expressed as: Young's modulus E = a × (1 / T²) ave )+b.

[0049] Furthermore, in step five, we obtain 1 / T2. ave-new The method is as follows:

[0050] 1 / T2 ave-new =f cr-new / T2 cr-new +f int-new / T2 int-new +f am1-new / T2 am1-new +f am2-new / T2 am2-new The content of crystal regions f cr-new =A(0) cr-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], interface content f int-new =A(0) int-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new Amorphous region content f am1-new =A(0) am1-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new], f am2-new =A(0) am2-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], i.e. f cr-new +f int-new +f am1-new +f am2-new =1.

[0051] Furthermore, the calculation method in step five also includes taking 1 / T2 ave-new Substituting into step three, E = a × (1 / T2) ave )+b, find E new =a×(1 / T2) ave-new )+b.

[0052] To further illustrate this, a detailed description is provided below with reference to specific embodiments.

[0053] Example 1:

[0054] A device for measuring the Young's modulus of polybutene-1 includes a hot press, a pneumatic sample cutter, a heating device, a tensile tester, an NMR instrument, and a storage device, wherein the hot press, the pneumatic sample cutter, the heating device, the tensile tester, the NMR instrument, and the storage device are all connected to a control system.

[0055] The hot press includes a hot press mold, which is used to hot press polybutene-1 and eliminate past thermal history in the process;

[0056] The pneumatic sample cutter includes a cutter, which is used to cut the hot-pressed sample to the size that meets the requirements of the tensile tester.

[0057] The heating device is used to heat treat the sample, and it can adjust the heating temperature to make the sample crystallize isothermally at different temperatures to obtain samples with different lamellar thicknesses.

[0058] The tensile tester includes a hot stage, which can adjust the temperature of the hot stage to change the temperature of the polybutene-1 sample, thereby enabling tensile tests to be performed at different temperatures and testing its Young's modulus.

[0059] The nuclear magnetic resonance instrument is a low-field solid-state nuclear magnetic resonance instrument with a resonance frequency of 19.65 MHz;

[0060] The memory contains a computer program capable of performing the following measurement methods, the program comprising:

[0061] Step 1: Measure the stress-strain curves of polybutene-1 samples at several different tensile temperatures and different crystallization temperatures using the tensile instrument described in the device, and obtain the Young's modulus E of polybutene-1 at different crystallization temperatures and different tensile temperatures.

[0062] Step 2: Using the nuclear magnetic resonance (NMR) instrument described in the apparatus, detect the T2 relaxation curves of polybutene-1 at the corresponding crystallization temperature and test temperature of the above sample in Step 1. Fit the T2 relaxation curves using Abragamian, Gaussian, and two exponential functions to obtain the T2 relaxation time T2 of the crystalline region. cr And amplitude A(0) cr The T2 relaxation time of the interface int And amplitude A(0) int And the T2 relaxation time of the amorphous region. am1 T2 am2 And amplitude A(0) am1 A(0) am2 ;Utilizing the relaxation time T2 of each phase region cr T2 int T2 am1 T2 am2 and amplitude A(0) cr A(0) int A(0) am1 A(0) am2 The average relaxation rate of the sample was calculated as 1 / T2. ave .

[0063] Step 3: Using a computer program, compare the Young's modulus E obtained in Step 1 with the average relaxation rate 1 / T2 of the sample. ave Perform a fitting operation to obtain the corresponding fitting function;

[0064] Step 4: Use the nuclear magnetic resonance instrument described in the device to detect the relaxation curves of polybutene-1 samples at different crystallization temperatures and different test temperatures. new The T2 relaxation curve was fitted using the Abragaimian function, the Gaussian function, and two exponential functions. new To obtain the T2 relaxation time T2 of the new crystal region cr-new And amplitude A(0) cr-new The T2 relaxation time of the interface int-new And amplitude A(0) int-new T2 relaxation time of amorphous region am1-new and T2 am2-new And amplitude A(0) am1-new A(0) am2-new ;Utilizing the relaxation time T2 of each phase region cr-new T2 int-new T2 am1-newT2 am2-new and amplitude A(0) cr-new A(0) int-new A(0) am1-new A(0) am2-new The average relaxation rate of the sample was calculated as 1 / T2. ave-new ;

[0065] Step 5: Calculate the average relaxation rate 1 / T2 obtained in Step 4. ave-new By substituting the values ​​into the fitting function from step three, we can obtain the Young's modulus E of polybutene-1 at any test temperature corresponding to different crystallization temperatures. new .

[0066] Furthermore, in step three, 1 / T2 is calculated. ave The method is as follows:

[0067] 1 / T2 ave =f cr / T2 cr +f int / T2 int +f am1 / T2 am1 +f am2 / T2 am2 The content of crystal regions f cr =A(0) cr / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], interface content f int =A(0) int / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 Amorphous region content f am1 =A(0) am1 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], f am2 =A(0) am2 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], i.e. f cr +f int +f am1 +f am2 =1.

[0068] Furthermore, in step three, a linear function is used to fit 1 / T2. ave The relationship between Young's modulus and this linear function is expressed as: Young's modulus E = a × (1 / T²) ave )+b.

[0069] Furthermore, in step five, we obtain 1 / T2. ave-new The method is as follows:

[0070] 1 / T2 ave-new =f cr-new / T2 cr-new +f int-new / T2 int-new +f am1-new / T2 am1-new +f am2-new / T2 am2-new The content of crystal regions f cr-new =A(0) cr-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], interface content f int-new =A(0) int-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new Amorphous region content f am1-new =A(0) am1-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], f am2-new =A(0) am2-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], i.e. f cr-new +f int-new +f am1-new +f am2-new =1.

[0071] Furthermore, the calculation method in step five also includes taking 1 / T2 ave-new Substituting into step three, E = a × (1 / T2) ave )+b, find E new =a×(1 / T2) ave-new )+b.

[0072] When performing actual measurements using this measuring instrument, the commercial polybutene-1 sample is first placed on the hot press described in this application to melt and press into a sheet to eliminate thermal history. Then, pressure is applied and maintained to ensure that the sample can fully fill the entire hot press mold.

[0073] The hot-pressed sample was then transferred to the heating device described in this application. The heating device was set to 0°C (i.e., quenching), 50°C, and 95°C, so that the sample could complete isothermal crystallization at the corresponding temperature. After standing, the sample of crystal form I was obtained.

[0074] The sample is transferred to a pneumatic sample cutter, which cuts the crystal form I sample sheet into dumbbell-shaped strips that meet the requirements of the tensile tester.

[0075] The samples were transferred to a tensile testing instrument, and the temperature of the hot stage was adjusted to 50, 70 and 90 °C. Samples with different crystallization temperatures were stretched at 50, 70 and 90 °C respectively, with a stretching rate of 20 μm / s. The corresponding stress-strain curves were recorded, and the elastic deformation region of the stress-strain curves was fitted to obtain the Young's modulus E of polybutene-1 at different crystallization temperatures and different stretching temperatures.

[0076] The above samples were transferred to the low-field solid-state nuclear magnetic resonance instrument described in this application. Single-pulse nuclear magnetic resonance (SPE) sequences were used to test the free-induction decay curves of polybutene-1 samples crystallized isothermally at 0℃ (i.e., quenched), 50℃, and 95℃ at 50℃, 70℃, and 90℃, respectively. Spin echo (HEPS) sequences were used to obtain decay curves with longer decay times for the corresponding samples. The T2 relaxation curves measured by SPE and HEPS were combined at decay times of 200–400 μs to obtain the final determined T2 relaxation curve. The T2 relaxation measured by the instrument is the sum of contributions from all phase regions. Abragamian, Gaussian, and two exponential functions were used to fit the relaxation components of the crystalline region, interface, and two amorphous regions of polybutene-1 crystal form I, respectively. The relaxation in the amorphous region includes faster-decreasing relaxation originating from network chains and slower-decreasing relaxation originating from rapidly moving chain ends. After fitting, the T2 relaxation time T2 of the crystalline region can be obtained. cr And amplitude A(0) cr T2 relaxation time of the interface int And amplitude A(0) int And the T2 relaxation time of the amorphous region. am1 T2 am2 And amplitude A(0) am1 A(0) am2 .

[0077]

[0078] Using the relaxation time T2 of each phase region cr T2int T2 am1 T2 am2 and amplitude A(0) cr A(0) int A(0) am1 A(0) am2 The average relaxation rate of the sample was calculated as 1 / T2. ave ,Right now:

[0079] 1 / T2 ave =f cr / T2 cr +f int / T2 int +f am1 / T2 am1 +f am2 / T2 am2 ,

[0080] The crystal region content f cr =A(0) cr / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ],

[0081] Interface content f int =A(0) int / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ],

[0082] Amorphous region content f am1 =A(0) am1 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ],

[0083] f am2 =A(0) am2 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ].

[0084] The computer program stored in the storage device of this application is used to calculate Young's modulus and the corresponding 1 / T2. ave Perform fitting analysis and plot the curve;

[0085] The fitted curve shows a linear relationship, and the equation of this linear function is: Young's modulus E = 13367 × (1 / T2) ave )-401, and the corresponding fitting function is obtained.

[0086] The target crystallization temperature and Young's modulus of polybutene-1 at the target stretching temperature were calculated using a fitting function. In this embodiment, the crystallization temperature was specifically selected as 85℃ and the stretching temperature as 50℃, 70℃, and 90℃.

[0087] Using the low-field solid-state nuclear magnetic resonance instrument described in this application, the T2 relaxation curves of polybutene-1 samples isothermally crystallized at 85℃ were measured at 50℃, 70℃, and 90℃ using single-pulse nuclear magnetic resonance (SPE) and spin echo (HEPS) sequences. new The T2 relaxation curves were fitted using Abragamian, Gaussian, and two exponential functions. new To obtain the T2 relaxation time T2 of the new crystal region cr-new And amplitude A(0) cr-new The T2 relaxation time of the interface int-new And amplitude A(0) int-new T2 relaxation time of amorphous region am1-new and T2 am2-new And amplitude A(0) am1-new A(0) am2-new .

[0088] The new T2 relaxation time obtained new Substitute the fitting function into the calculation, and use the relaxation time T2 of each phase region. cr-new T2 int-new T2 am1-new T2 am2-new and amplitude A(0) cr-new A(0) int-new A(0) am1-new A(0) am2-new The average relaxation rate of the sample was calculated as 1 / T2. ave-new :

[0089] 1 / T2 ave-new =f cr-new / T2 cr-new +f int-new / T2 int-new +f am1-new / T2 am1-new +f am2-new / T2 am2-new ,

[0090] The crystal region content f cr-new =A(0) cr-new / [A(0) cr-new +A(0)int-new +A(0) am1-new +A(0) am2-new ],

[0091] Interface content f int-new =A(0) int-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ],

[0092] Amorphous region content f am1-new =A(0) am1-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ],

[0093] f am2-new =A(0) am2-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ],

[0094] This allows us to obtain the 1 / T2 of polybutene-1 at different crystallization temperatures and test temperatures. ave-new , 1 / T2 ave-new Substituting E = 13367 × (1 / T2) ave )-401, find E new .

[0095] Comparative Example 1

[0096] Tensile specimens were prepared from polybutene-1 samples that were isothermally crystallized at 85℃. The stress-strain curves of the samples were measured at 50℃, 70℃, and 90℃ using a tensile instrument. The Young's modulus E (tensile) of polybutene-1 at different tensile temperatures was obtained and compared with the data calculated by the above formula. The data were within the error range, proving that the measuring device described in this application can quickly measure the Young's modulus of polybutene-1 samples.

[0097] Table 1 compares the Young's modulus obtained by the measuring device in Example 1 with that in Comparative Example 1.

[0098] Tensile temperature / Test temperature [°C] <![CDATA[1 / T2 ave-new [μs -1 ]]]> <![CDATA[E new [MPa]]]> E (tensile strength) [MPa] 50 0.04392 186 183 70 0.04113 148 143 90 0.04016 135 125

[0099] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

[0100] If this patent uses terms such as "first" and "second" to define components, those skilled in the art should know that the use of "first" and "second" is merely for the convenience of describing the invention and simplifying the description, and the above terms have no special meaning.

[0101] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this invention is defined by the appended claims and their equivalents.

[0102] In the description of this invention, it should be understood that the terms "front", "rear", "left", "right", "center", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of this invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

Claims

1. A device for measuring the Young's modulus of polybutene-1, characterized in that: It includes a hot press, a pneumatic sample cutter, a heating device, a tensile tester, an NMR instrument, and a storage device, and the hot press, pneumatic sample cutter, heating device, tensile tester, NMR instrument, and storage device are all connected to the control system. The hot press includes a hot press mold, which is used to hot press polybutene-1 and eliminate past thermal history in the process; The pneumatic sample cutter includes a cutter, which is used to cut the hot-pressed sample to the size that meets the requirements of the tensile tester. The heating device is used to heat treat the sample, and it can adjust the heating temperature to make the sample crystallize isothermally at different temperatures to obtain samples with different lamellar thicknesses. The tensile tester can adjust the tensile temperature to perform tensile tests at different temperatures and test its Young's modulus. The nuclear magnetic resonance instrument is a low-field solid-state nuclear magnetic resonance instrument; The memory contains a computer program capable of performing a measurement method, which includes: Step 1: Measure the stress-strain curves of polybutene-1 samples at several different tensile temperatures and different crystallization temperatures using the tensile instrument described in the device, and obtain the Young's modulus E of polybutene-1 at different crystallization temperatures and different tensile temperatures. Step 2: Using the nuclear magnetic resonance (NMR) instrument described in the apparatus, detect the T2 relaxation curves of polybutene-1 at the corresponding crystallization temperature and test temperature of the above sample in Step 1. Fit the T2 relaxation curves using Abragamian, Gaussian, and two exponential functions to obtain the T2 relaxation time T2 of the crystalline region. cr And amplitude A(0) cr The T2 relaxation time of the interface int And amplitude A(0) int And the T2 relaxation time of the amorphous region. am1 T2 am2 And amplitude A(0) am1 A(0) am2 ;Utilizing the relaxation time T2 of each phase region cr T2 int T2 am1 T2 am2 and amplitude A(0) cr A(0) int A(0) am1 A(0) am2 The average relaxation rate of the sample was calculated as 1 / T2. ave . Step 3: Combine the Young's modulus E obtained in Step 1 with the average relaxation rate of the sample 1 / T2 ave Perform a fitting operation to obtain the corresponding fitting function; Step 4: Use the nuclear magnetic resonance instrument described in the device to detect the relaxation curves of polybutene-1 samples at different crystallization temperatures and different test temperatures. new The T2 relaxation curve was fitted using the Abragaimian function, the Gaussian function, and two exponential functions. new To obtain the T2 relaxation time T2 of the new crystal region cr-new And amplitude A(0) cr-new The T2 relaxation time of the interface int-new And amplitude A(0) int-new T2 relaxation time of amorphous region am1-new and T2 am2-new And amplitude A(0) am1-new A(0) am2-new ;Utilizing the relaxation time T2 of each phase region cr-new T2 int-new T2 am1-new T2 am2-new and amplitude A(0) cr-new A(0) int-new A(0) am1-new A(0) am2-new The average relaxation rate of the sample was calculated as 1 / T2. ave-new ; Step 5: Calculate the average relaxation rate 1 / T2 obtained in Step 4. ave-new By substituting the values ​​into the fitting function from step three, we can obtain the Young's modulus E of polybutene-1 at any test temperature corresponding to different crystallization temperatures. new .

2. A measuring device as described in claim 1, characterized in that... In step three, 1 / T2 is calculated. ave The method is as follows: 1 / T2 ave =f cr / T2 cr +f int / T2 int +f am1 / T2 am1 +f am2 / T2 am2 The content of crystal regions f cr =A(0) cr / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], interface content f int =A(0) int / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 Amorphous region content f am1 =A(0) am1 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], f am2 =A(0) am2 / [A(0) cr +A(0) int +A(0) am1 +A(0) am2 ], i.e. f cr +f int +f am1 +f am2 =1.

3. A measuring device as described in claim 1, characterized in that: In step three, a linear function is used to fit 1 / T2. ave The relationship between this linear function and Young's modulus is expressed as follows: Young's modulus E = a × (1 / T2) ave )+b.

4. A measuring device as described in claim 1, characterized in that... Step 5 yields 1 / T2 ave-new The method is as follows: 1 / T2 ave-new =f cr-new / T2 cr-new +f int-new / T2 int-new +f am1-new / T2 am1-new +f am2-new / T2 am2-new The content of crystal regions f cr-new =A(0) cr-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], interface content f int-new =A(0) int-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new Amorphous region content f am1-new =A(0) am1-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], f am2-new =A(0) am2-new / [A(0) cr-new +A(0) int-new +A(0) am1-new +A(0) am2-new ], i.e. f cr-new +f int-new +f am1-new +f am2-new =1.

5. A measuring device as described in claim 1, characterized in that... The calculation method in step five also includes taking 1 / T2 ave-new Substituting into step three, E = a × (1 / T2) ave )+b, find E new =a×(1 / T2) ave-new )+b.

6. A measuring device as described in claim 1, characterized in that... The stretching apparatus includes a heating stage, which is used to change the stretching temperature.

7. A measuring device as described in claim 1, characterized in that... The resonance frequency of the nuclear magnetic resonance instrument is 19.65MHz.

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