Device and method for preparing methyl methacrylate adhesive compression sample

Abstract

The invention belongs to the technical field of polymer mechanical property testing, and particularly discloses a methyl methacrylate adhesive compression sample preparation device and method.The preparation device comprises a compression sample mold, an injector and a compression sample polisher, and the compression sample mold comprises a raw material injection end and a sample taking section; the compressed sample polisher comprises a sample clamping part, a clamping and screwing screw opening and a handheld end. According to the device and the method for preparing the methyl methacrylate adhesive sample, the problem that the compression sample cannot be prepared from a high-viscosity and low-fluidity material is solved by adopting the method for preparing the compression sample by using the injector and the mold, the preparation method is used for replacing the previous method for preparing the sample by pouring, and a pressurized injection method is adopted; holes are effectively avoided, and it is guaranteed that the mold can be filled with materials.

Description

Technical Field

[0001] The invention relates to the technical field of polymer mechanical property testing, in particular to a device and method for preparing a methyl methacrylate adhesive sample. Background Art

[0002] Methyl methacrylate (MMA) adhesive is the main material for thick bonded composite joints. After curing, it has excellent mechanical strength, chemical corrosion resistance and good electrical insulation properties. Considering the influence of thickness on the strength of bonded joints, in addition to the bond strength test, the tensile and compressive properties of MMA adhesives need to be tested. According to the requirements of GB / T8813-2020 "Determination of Compression Properties of Rigid Foam Plastics", circular or square specimens with a thickness of at least 10 mm need to be prepared. When companies produce compression specimens, they generally use raw materials for mold curing or cut finished materials for preparation. However, MMA adhesives will bond most metal materials, and the temperature during the cutting process will affect the compression performance test. The viscosity before curing, the brittleness after curing and the temperature sensitivity make the compression specimens prepared by conventional methods have uneven surface flatness, difficult to accurately measure the size, and changes in mechanical properties. These problems affect the accuracy of the test data, resulting in large discreteness and poor accuracy of the compression performance data tested.

[0003] The existing technology is unable to prepare small batch compression samples for high viscosity and low fluidity MMA materials. The main reasons are as follows:

[0004] 1. MMA material has high viscosity. When casting with a mold, it will adhere to the mold and cannot be demoulded.

[0005] 2. MMA material has poor fluidity. Using general casting molds will produce defects such as holes and gaps. Samples with defects cannot be accurately tested for mechanical properties.

[0006] 3. Material properties are related to temperature. The cutting method will produce unnecessary temperature defects and defects with low precision.

[0007] Therefore, there is an urgent need to provide a method for preparing a methyl methacrylate adhesive sample, and the prepared compression sample can solve the problems of the prior art. Summary of the invention

[0008] The purpose of the present invention is to provide a methyl methacrylate adhesive sample preparation device and method, which uses a syringe and a mold to prepare a compression sample, solving the problem that high-viscosity, low-fluidity materials cannot make compression samples. The preparation method of the present invention replaces the previous method of pouring and making samples, and adopts a pressurized injection method, which effectively avoids the generation of holes and ensures that the material can fill the mold.

[0009] To achieve the above-mentioned purpose, the present invention provides a methyl methacrylate adhesive compression sample preparation device, including a compression sample mold, a syringe, and a compression sample grinder. The compression sample mold includes a raw material injection end and a sample collection section. The compression sample grinder includes a sample clamping part, a clamping and tightening screw, and a handheld end.

[0010] Preferably, a slot is provided on one side of the sample clamping part, and clamping and tightening screws are provided on both sides of the slot. The top opening of the sample clamping part is arranged and its bottom is integrally arranged with the handheld end. The bottom of the sample clamping part corresponding to one side of the slot is recessed upward and does not contact the handheld end.

[0011] Preferably, the raw material injection end and the sample collection section are both located inside the compression sample mold, and the raw material injection end and the sample collection section are connected, and the bottom of the sample collection section is flush with the bottom of the compression sample mold and is open.

[0012] Preferably, the syringe comprises, from left to right, an injection end, a conical mixing head, a raw material storage tank, and a syringe pressurizing end.

[0013] Preferably, the compression specimen mold is made of polytetrafluoroethylene or other hard non-metallic materials.

[0014] Preferably, the syringe is made of polytetrafluoroethylene material.

[0015] Preferably, the compression sample grinder is made of aluminum alloy material.

[0016] The present invention also provides a method for preparing a compression sample of a methyl methacrylate adhesive. The method is implemented by a preparation device and comprises the following steps:

[0017] Step 1: Mix the methyl methacrylate main agent and the curing agent and put them into the raw material storage tank of the syringe, apply pressure through the pressurizing end of the syringe, mix them twice through the conical mixing head, and use the injection end of the syringe to pressurize and inject the methyl methacrylate adhesive into the raw material injection end of the compression sample mold. The methyl methacrylate adhesive at the raw material injection end flows to the sample sampling section;

[0018] Step 2: Wait for the methyl methacrylate adhesive in the compression sample mold to solidify and form, select the molded methyl methacrylate adhesive sample in the sample sampling section of the compression sample mold for cutting, and the cutting length must be 1mm-3mm greater than the standard sample height;

[0019] Step 3: Place the cut sample into the sample clamping part through the sample clamping end, fix it to the sample clamping part of the sample grinder by clamping and tightening the screw, and grind and polish it with a polishing machine to finally obtain a methyl methacrylate adhesive compression sample with flush upper and lower surfaces and precise size.

[0020] The advantages and beneficial effects of the present invention using the above-mentioned methyl methacrylate adhesive compression sample preparation device and method are as follows:

[0021] 1. The method of preparing compression specimens using a syringe and a mold solves the problem that compression specimens cannot be prepared using materials with high viscosity and low fluidity.

[0022] 2. The mold of the present invention is divided into a raw material injection end and a sample sampling section, and can be used with the same syringe to make compression specimens of different sizes; the sample grinder can adjust the diameter of the sample clamping end by clamping and tightening the screw, match different samples and ensure the parallelism of the upper and lower end surfaces of the compression sample; a hard polytetrafluoroethylene syringe can be used to secondary mix the curing agent and the methyl methacrylate adhesive main agent through a conical mixing head, and no adhesion occurs with the methyl methacrylate adhesive; the present invention replaces the previous method of casting to make samples, and adopts a pressurized injection method, which effectively avoids the generation of holes and ensures that the material can fill the mold.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a compression sample mold in a methyl methacrylate adhesive compression sample preparation device of the present invention;

[0025] Figure 2 It is a schematic diagram of a syringe in a device for preparing a compression sample of methyl methacrylate adhesive according to the present invention;

[0026] Figure 3 It is a schematic diagram of a compression sample grinder in a methyl methacrylate adhesive compression sample preparation device of the present invention;

[0027] Figure 4 It is the force displacement curve of the sample measured at a constant pressure head rate of the present invention, and the experimental result is repeated three times.

[0028] Reference numerals

[0029] 1. Raw material injection end; 2. Sample collection section; 3. Injection end; 4. Conical mixing head; 5. Raw material storage tank; 6. Syringe pressurization end; 7. Sample clamping end; 8. Clamping and tightening screw; 9. Hand-held end; 10. Slot; 11. Sample clamping part. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0031] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0032] Example 1

[0033] A device for preparing a compression sample of methyl methacrylate adhesive includes a compression sample mold, a syringe, and a compression sample grinder. The compression sample mold includes two parts: a raw material injection end 1 and a sample sampling section 2. The compression sample mold is made of polytetrafluoroethylene or other hard non-metallic materials. The compression sample grinder is made of aluminum alloy material. The compression sample grinder includes a sample clamping part 11, a clamping and tightening screw 8, and a handheld end 9. A slot 10 is provided on one side of the sample clamping part 11, and clamping and tightening screws 8 are provided on both sides of the slot 10. Bolts and nuts used in conjunction with the clamping and tightening screws 8 are provided in the clamping and tightening screws 8 (not shown in the figure). The top of the sample clamping part 11 is open and its bottom is integrally arranged with the handheld end 9. The bottom of the sample clamping part 11 corresponding to one side of the slot 10 is recessed upward and does not contact the handheld end 9. The square-edge clamping and tightening screw 8 adjusts the diameter of the sample clamping part 11 through a bolt.

[0034] The raw material injection end 1 and the sample collection section 2 are both located inside the compression sample mold, and the raw material injection end 1 and the sample collection section 2 are connected, and the bottom of the sample collection section 2 is flush with the bottom of the compression sample mold and is open. The compression sample mold is divided into the raw material injection end 1 and the sample collection section 2, which can be matched with the same syringe to make compression samples of different sizes. The length of the sample collection section should be at least three times greater than the height of the sample to facilitate the removal of the collection section with bad head and tail.

[0035] The syringe includes, from left to right, an injection end 3, a conical mixing head 4, a raw material storage tank 5, and a syringe pressurizing end 6. The syringe is made of polytetrafluoroethylene material.

[0036] like Figure 1 As shown, the compression specimen mold is made of polytetrafluoroethylene or other hard non-metallic materials, and is divided into two parts: a raw material injection end 1 and a specimen collection section 2. The compression specimen mold is not limited to Figure 1As shown, it can be a mold for making samples of other shapes. The compression sample mold material can be other materials except polytetrafluoroethylene, as long as it is guaranteed not to bond and react with the sample material, and a certain strength needs to be guaranteed.

[0037] like Figure 2 As shown, the syringe is divided into an injection end 3, a conical mixing head 4, a raw material storage tank 5 and a syringe pressurizing end 6. The syringe is made of polytetrafluoroethylene, will not adhere to methyl methacrylate, and has sufficient strength to withstand pressurized injection, and the conical mixing head 4 can also perform secondary mixing of the raw materials, which is an ideal pressurizing device. The syringe adopts a conical mixing head 4 to perform secondary mixing of the raw materials, which is not limited to the shape and material of the syringe.

[0038] like Figure 3 As shown, the compression sample grinder is made of aluminum alloy, which has certain deformation properties and can be made of wear-resistant materials. The sample clamping end 7 can adjust the clamping diameter through the bolts and nuts located in the clamping screw 8, and is equipped with a handheld end 9 for easy grinding. The compression sample grinder can adjust the diameter of the clamping end through the clamping screw 8 to match different samples and ensure the parallelism of the upper and lower end surfaces of the compression sample.

[0039] A method for preparing a compression sample of a methyl methacrylate adhesive, which replaces the previous method of casting and making the sample, adopts a pressurized injection method, effectively avoids the generation of holes, and ensures that the material can fill the mold, comprising the following steps:

[0040] Step 1: Mix the methyl methacrylate main agent and the curing agent and put them into the raw material storage tank 5 of the syringe, apply pressure through the syringe pressurizing end 6, mix them twice through the conical mixing head 4, and use the injection end 3 of the syringe to pressurize and inject the methyl methacrylate adhesive into the raw material injection end 31 of the compression sample mold, and the methyl methacrylate adhesive at the raw material injection end 1 flows to the sample sampling section 2;

[0041] Step 2: Wait for the methyl methacrylate adhesive in the compression sample mold to solidify and form, select the molded methyl methacrylate adhesive sample of the sample sampling section 2 in the compression sample mold for cutting, and the cutting length must be 1mm-3mm greater than the standard sample height;

[0042] Step 3: Place the cut sample into the sample clamping part 11 through the sample clamping end 7, fix it to the sample clamping part 11 of the sample grinder by clamping and tightening the screw 8, and grind and polish it with a polishing machine to finally obtain a methyl methacrylate adhesive compression sample with flush upper and lower surfaces and precise size.

[0043] The sample prepared in the present invention is a compression sample of methyl methacrylate adhesive, but it is also applicable to other materials with great viscosity that cannot be used to prepare samples.

[0044] Example 2

[0045] By the preparation method of Example 1, a methyl methacrylate adhesive compression specimen with a height of 8 mm was prepared, and its force displacement curve was measured at a constant pressure head rate. The experimental results were repeated three times. Figure 4 As shown, the measured data of the prepared samples have good consistency.

[0046] Therefore, the present invention adopts the above-mentioned methyl methacrylate adhesive sample preparation device and method, and uses a syringe and a mold to prepare a compression sample, which solves the problem that high-viscosity and low-fluidity materials cannot make compression samples. The preparation method of the present invention replaces the previous method of pouring and making samples, and adopts a pressurized injection method, which effectively avoids the generation of holes and ensures that the material can fill the mold.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A methyl methacrylate adhesive compression sample preparation device, characterized in that: The compression specimen grinder comprises a compression specimen mold, a syringe and a compression specimen grinder. The compression specimen mold comprises a raw material injection end and a specimen collection section. The compression specimen grinder comprises a specimen clamping portion, a clamping screw and a hand-held end.

2. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: A slot is provided on one side of the sample clamping part, and clamping and tightening screws are provided on both sides of the slot. The top of the sample clamping part is opened and its bottom is integrated with the handheld end. The bottom of the sample clamping part corresponding to one side of the slot is recessed upward and does not contact the handheld end.

3. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: The raw material injection end and the sample collection section are both located inside the compression sample mold, and the raw material injection end and the sample collection section are communicated, and the bottom of the sample collection section is flush with the bottom of the compression sample mold and is open.

4. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: The syringe includes an injection end, a conical mixing head, a raw material storage tank, and a syringe pressurizing end from left to right.

5. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: The compression sample mold is made of polytetrafluoroethylene or other hard non-metallic materials.

6. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: The syringe is made of polytetrafluoroethylene material.

7. A methyl methacrylate adhesive compression sample preparation device according to claim 1, characterized in that: The compression sample grinder is made of aluminum alloy material.

8. A method for preparing a compression sample of methyl methacrylate adhesive, characterized in that: The method is realized by the preparation device according to any one of claims 1 to 4, comprising the following steps: Step 1: Mix the methyl methacrylate main agent and the curing agent and put them into the raw material storage tank of the syringe, apply pressure through the pressurizing end of the syringe, mix them twice through the conical mixing head, and use the injection end of the syringe to pressurize and inject the methyl methacrylate adhesive into the raw material injection end of the compression sample mold. The methyl methacrylate adhesive at the raw material injection end flows to the sample sampling section; Step 2: Wait for the methyl methacrylate adhesive in the compression sample mold to solidify and form, select the molded methyl methacrylate adhesive sample in the sample sampling section of the compression sample mold for cutting, and the cutting length must be 1mm-3mm greater than the standard sample height; Step 3: Place the cut sample into the sample clamping part through the sample clamping end, fix it to the sample clamping part of the sample grinder by clamping and tightening the screw, and grind and polish it with a polishing machine to finally obtain a methyl methacrylate adhesive compression sample with flush upper and lower surfaces and precise size.

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