阅读说明：本技术 一种声磁或射频防盗硬标签、硬标签外壳及其制备方法 (Acoustic magnetic or radio frequency anti-theft hard tag, hard tag shell and preparation method thereof ) 是由 张曙 虞丽京 刘曹飞 廖娜 于 2021-07-13 设计创作，主要内容包括：本发明公开了一种声磁或射频防盗硬标签、硬标签外壳及其制备方法。本发明声磁或射频防盗硬标签外壳通过100％的废旧ABS塑料制成,或者通过废旧ABS塑料及改性材料制成,并利用上下外壳形成的空腔结构,使其具有非常好的抗冲击强度,即便用1kg或10kg铁锤连续砸击直至裂开,此时展现有塑性断裂,非完全脆性直接断裂,能满足防盗需求,而且实现了变废为宝,满足了广大客户对于具绿色倾向声磁或射频防盗硬标签的迫切需求。(The invention discloses an acoustic magnetic or radio frequency anti-theft hard tag, a hard tag shell and a preparation method thereof. The shell of the acoustic-magnetic or radio-frequency anti-theft hard tag is made of 100% of waste ABS plastic or waste ABS plastic and modified materials, and a cavity structure formed by the upper shell and the lower shell is utilized, so that the acoustic-magnetic or radio-frequency anti-theft hard tag has very good impact strength, even if a hammer of 1kg or 10kg is used for continuously pounding the tag until the tag is cracked, the tag shows plastic fracture and is not completely brittle and directly fractured, the anti-theft requirement can be met, waste is changed into valuable, and the urgent requirement of customers on the acoustic-magnetic or radio-frequency anti-theft hard tag with a green trend is met.)

1. The acoustic magnetic or radio frequency anti-theft hard tag shell is characterized in that the acoustic magnetic or radio frequency anti-theft hard tag shell material comprises a modified material and waste ABS plastic; based on the total weight of the acoustic magnetic or radio frequency anti-theft hard tag shell material, the content of the waste ABS plastic is 1-100%, and the total content of the modified material and the new ABS plastic is 0-99%.

2. The acousto-magnetic or rf anti-theft hard tag casing according to claim 1, characterized in that the content of waste ABS plastic is 100% calculated on the total weight of the acousto-magnetic or rf anti-theft hard tag casing material.

3. The acoustic-magnetic or radio frequency anti-theft hard tag shell according to claim 1, wherein the modifying material comprises at least one of glycidyl methacrylate grafted nitrile rubber and virgin ABS plastic, and the glycidyl methacrylate grafted nitrile rubber is prepared by reacting nitrile rubber, glycidyl methacrylate and styrene under the action of an initiator.

4. The acoustic-magnetic or radio-frequency anti-theft hard tag shell according to claim 3, wherein the content of the waste ABS plastic is 92-98%, the content of the glycidyl methacrylate grafted nitrile rubber is 2-8%, preferably the content of the waste ABS plastic is 94%, and the content of the glycidyl methacrylate grafted nitrile rubber is 6%; or based on the total weight of the shell material of the acoustic magnetic or radio frequency anti-theft hard tag, the content of the waste ABS plastic is 1-99%, the content of the new ABS plastic is 1-99%, preferably, the content of the waste ABS plastic is 1-99%, and the content of the new ABS plastic is 1-49%.

5. The acousto-magnetic or rf anti-theft hard tag cover according to claim 3, characterized in that the ratio of the weight of nitrile rubber to the total weight of nitrile rubber, glycidyl methacrylate, styrene and initiator is 90-99%.

6. The acousto-magnetic or RF anti-theft hard tag cover according to claim 1, characterized in that the acousto-magnetic or RF anti-theft hard tag cover material has an impact strength of 8.21-18.02kJ/m²。

7. A preparation method of an acoustic magnetic or radio frequency anti-theft hard tag shell is characterized by comprising the following steps:

granulating waste ABS plastics, or mixing the waste ABS plastics and new ABS plastics for granulation, or mixing modified materials and the waste ABS plastics for reactive extrusion and then granulating to obtain ABS plastic granules;

and the ABS plastic granules are injected into the upper and lower shells of the acoustic magnetic or radio frequency anti-theft hard tag through a mould.

8. The method for preparing the acoustic-magnetic or radio frequency anti-theft hard tag shell according to claim 7, wherein the modified material is acrylonitrile butadiene rubber grafted with glycidyl methacrylate, and the method further comprises the following steps: and carrying out melt grafting on the nitrile rubber, glycidyl methacrylate and styrene under the action of an initiator to obtain the glycidyl methacrylate grafted nitrile rubber.

9. An acousto-magnetic or radio frequency anti-theft hard tag characterized by comprising an acousto-magnetic or radio frequency anti-theft hard tag housing according to any one of claims 1 to 6.

10. The acousto-magnetic or rf anti-theft hard tag according to claim 9, wherein the acousto-magnetic or rf anti-theft hard tag is fixed on the surface of an anvil and is hit continuously with a hammer of 1-10kg until it is cracked, at which time the acousto-magnetic or rf anti-theft hard tag exhibits plastic fracture but not completely brittle fracture.

11. The acousto-magnetic or rf anti-theft hard tag according to claim 9, characterized in that the acousto-magnetic anti-theft alarm has an alarm frequency of 57.5-58.5 kHz; the alarm frequency of the radio frequency anti-theft alarm is 8.1-8.3 MHz.

Technical Field

The invention belongs to the technical field of anti-theft hard tags, and relates to an acoustic magnetic or radio frequency anti-theft hard tag, a hard tag shell and a preparation method thereof.

Background

An Acoustic Magnetic (AM)/Radio Frequency (RF) anti-theft hard tag (called as a hard tag or a hard tag for short) generally comprises an upper shell and a lower shell which are formed by injection molding of ABS plastic, and after a pin lock core and an alarm piece are arranged in the shells, the two shells are ultrasonically welded to form a cavity into a whole, so that the anti-theft hard tag is obtained and is commonly used for the anti-theft of soft goods. After the customer selects the commodity, the customer can pay at the cashier desk, and the cashier takes off the hard mark by the nail taking device. If the thief tries to take the commodity out of the store without paying, the hard tag which is not taken down triggers an alarm when the commodity passes through the doorway alarm antenna, so that the anti-theft effect is achieved.

Currently, hard tags are sold in billions per year worldwide, and are usually made of brand new ABS plastic. However, after the hard tag is used for several years, the hard tag must be discarded due to the abrasion of the lock cylinder and the like, so that the environment is polluted. With the introduction of "plastic-limited order" in various countries, merchants need to use recycled plastics to prepare hard acoustic-magnetic/radio-frequency anti-theft tags (i.e., "pro-green" products which are beneficial to environmental protection) to accomplish the continuously enhanced environmental protection task.

At present, some regenerated ABS master batches with relatively stable quality and large quantities are available on the market, but most of the materials are recycled from electronic and electric products (such as household appliance shell plastics). In the structure of the ABS plastic, because the alpha hydrogen beside C is active, the ABS plastic is easily affected by heat, mechanical stress, ions or ultraviolet radiation in long-term service under the aerobic condition to generate an oxide active intermediate, and finally the ABS plastic is subjected to oxidative degradation. The comprehensive performance and environmental adaptability of the aged ABS plastic are obviously reduced, especially the impact strength is greatly reduced, the ABS plastic has larger brittleness and is easy to break and break, so the technical personnel in the field think that the waste ABS plastic is difficult to be applied to manufacturing the anti-theft hard label shell with better anti-theft effect. Therefore, no report on the acoustic magnetic/radio frequency anti-theft hard tag shell made of waste ABS plastic exists in the current market.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a sound magnetic or radio frequency anti-theft hard tag, a hard tag shell and a preparation method thereof.

In order to achieve the above object, in a first aspect, the present invention provides an acoustic magnetic or radio frequency anti-theft hard tag shell, which comprises modified materials and waste ABS plastics; based on the total weight of the acoustic magnetic or radio frequency anti-theft hard tag shell material, the content of the waste ABS plastic is 1-100%, and the total content of the modified material and the new ABS plastic is 0-99%.

The acoustic magnetic or radio frequency anti-theft hard label made of the shell has good impact resistance, and is continuously knocked to crack by a 1kg or 10kg hammer, so that the hard label shows plastic fracture (whitening phenomenon exists near the crack and the crack is fractured after plastic deformation) and not complete brittle fracture (the crack is directly fractured without deformation).

Preferably, the content of the waste ABS plastic is 100% by weight based on the total weight of the acoustic magnetic or radio frequency anti-theft hard tag shell material. The inventor considers that the shell of the acoustic magnetic or radio frequency anti-theft hard tag made of 100% waste ABS plastic is continuously knocked to crack by using a 1kg or 10kg hammer, and brittle fracture can occur, but the fracture state of the shell of the hard tag made by using the shell of the hard tag after continuous knocking is almost the same as that of the shell of the hard tag made of brand-new ABS plastic, and the shell of the hard tag shows plastic fracture (whitening phenomenon exists near a crack and the crack fractures after plastic deformation exists) and not completely brittle fracture (the crack does not deform and directly fractures) (as shown in figures 1a and 1 b), which shows that a cavity structure formed by welding an upper shell and a lower shell of the hard tag has good impact resistance effect, the work of the invention shows that even if the impact resistance of the material per se is obviously reduced, the qualified anti-theft hard tag with impact resistance can be made by using 100% waste ABS plastic, and the invention is beyond the expectation range of technicians in the field, producing unexpected technical effects.

Preferably, the modified material comprises glycidyl methacrylate grafted nitrile rubberThe acrylonitrile-butadiene rubber grafted by the glycidyl methacrylate is prepared by reacting the acrylonitrile-butadiene rubber, the glycidyl methacrylate and styrene under the action of an initiator. The nitrile-butadiene rubber (NBR) is a synthetic rubber prepared by copolymerizing butadiene and acrylonitrile, and has the same components with acrylonitrile-butadiene-styrene (ABS), so that the butadiene-acrylonitrile rubber grafted by the glycidyl methacrylate can supplement a butadiene (PB) phase in the waste ABS plastic, silver stripes can be triggered to absorb a certain amount of energy when the butadiene-acrylonitrile rubber is impacted, and meanwhile, the acrylonitrile-butadiene rubber grafted by the glycidyl methacrylate can supplement an acrylonitrile phase in the waste ABS plastic; the Glycidyl Methacrylate (GMA) structural unit in the glycidyl methacrylate grafted nitrile rubber has an epoxy group, and the epoxy group can react with hydroxyl and carboxyl generated by aging degradation of ABS, so that chain scission of waste ABS plastics caused by aging is connected, the molecular weight is increased, and the performance of the waste ABS plastics is further enhanced. The glycidyl methacrylate grafted nitrile rubber and the waste ABS plastic are subjected to reactive extrusion modification, so that the mechanical property of the waste ABS plastic can be improved, such as the impact strength is obviously improved. In the acoustic magnetic or radio frequency anti-theft hard label shell material, the weight content of the butadiene-acrylonitrile rubber grafted by the glycidyl methacrylate can be selected to be 2-8%, and when the weight content is 6%, the impact strength of the material can reach 18.01kJ/m²The weight content is increased to 253 percent, but when the weight content exceeds 6 percent, the impact strength of the material is reduced; with the increase of the weight content of the glycidyl methacrylate grafted nitrile rubber, the tensile strength of the material is gradually reduced, and when the weight content is more than 6%, the tensile strength of the material is reduced from the original 45.72MPa to 42.57MPa, because the nitrile rubber has lower yield stress and is polar rubber, and the addition of the nitrile rubber increases the rigidity of the waste ABS plastic, which causes the tensile strength of the blend to be slightly reduced. Because the retention value of the tensile strength of the aged waste ABS plastic is relatively high, the tensile strength is sacrificed by a small margin, the impact strength and other short board properties are greatly improved, and the regeneration material is very favorable for being improvedThe material performance can meet the requirement of preparing a high-quality recycled plastic acoustic magnetic/radio frequency anti-theft hard tag which meets the anti-theft requirement, namely a Green tendency (Pro-Green) acoustic magnetic or radio frequency anti-theft hard tag.

Preferably, based on the total weight of the acoustic magnetic or radio frequency anti-theft hard tag shell material, the content of the waste ABS plastic is 92-98%, the content of the glycidyl methacrylate grafted nitrile rubber is 2-8%, preferably, the content of the waste ABS plastic is 94%, and the content of the glycidyl methacrylate grafted nitrile rubber is 6%; or based on the total weight of the shell material of the acoustic magnetic or radio frequency anti-theft hard tag, the content of the waste ABS plastic is 1-99%, the content of the new ABS plastic is 1-99%, preferably, the content of the waste ABS plastic is 1-99%, and the content of the new ABS plastic is 1-49%.

Preferably, the ratio of the weight of the nitrile rubber to the total weight of the nitrile rubber, glycidyl methacrylate, styrene and initiator is from 90 to 99%.

Preferably, the weight ratio of nitrile rubber, glycidyl methacrylate, styrene and initiator is 188:6:6: 0.3.

Preferably, the impact strength of the shell material of the acoustic magnetic or radio frequency anti-theft hard tag is 8.21-18.02kJ/m²。

In a second aspect, the invention provides a method for preparing an acoustic magnetic or radio frequency anti-theft hard tag shell, which comprises the following steps:

granulating waste ABS plastics, or mixing the waste ABS plastics and new ABS plastics for granulation, or mixing modified materials and the waste ABS plastics for reactive extrusion and then granulating to obtain ABS plastic granules;

and the ABS plastic granules are injected into the upper and lower shells of the acoustic magnetic or radio frequency anti-theft hard tag through a mould.

Preferably, the modified material is acrylonitrile butadiene rubber grafted with glycidyl methacrylate, and the preparation method further comprises the following steps: and carrying out melt grafting on the nitrile rubber, glycidyl methacrylate and styrene under the action of an initiator to obtain the glycidyl methacrylate grafted nitrile rubber.

Preferably, the temperature of each section of an extruder adopted by the reactive extrusion is 180-230 ℃, the rotating speed of a main machine is 60r/min, and the feeding frequency is 2.5 Hz.

In a third aspect, the invention further provides an acousto-magnetic or radio-frequency anti-theft hard tag, which comprises the acousto-magnetic or radio-frequency anti-theft hard tag shell. Although fig. 1a,1b, 2a and 2b show the shape and structure of the acoustic-magnetic or rf anti-theft hard tag, the shape and structure of the acoustic-magnetic or rf anti-theft hard tag of the present invention are not limited thereto, and the shape and structure of the acoustic-magnetic or rf anti-theft hard tag of the present invention may be the same as those of any acoustic-magnetic or rf anti-theft hard tag in the art, and the acoustic-magnetic or rf anti-theft hard tag of any shape and structure in the art may exhibit plastic fracture (whitening phenomenon in the vicinity of the fracture and fracture after plastic deformation of the fracture) and not complete brittle fracture (direct fracture without deformation) as long as the hard tag is subjected to continuous tapping of the hard tag with a 1kg or 10kg hammer, using the shell material defined in the present invention.

Preferably, the alarm frequency of the acoustic magnetic anti-theft alarm part is 57.5-58.5 kHz.

Preferably, the alarm frequency of the radio frequency anti-theft alarm part is 8.1-8.3 MHz.

Compared with the prior art, the invention has the beneficial effects that: the shell of the acoustic-magnetic or radio-frequency anti-theft hard tag is made of 100% of waste ABS plastic or waste ABS plastic and modified materials, and an integrated cavity structure is formed by welding the upper shell and the lower shell, so that the acoustic-magnetic or radio-frequency anti-theft hard tag has very good impact strength, even if the upper shell and the lower shell are continuously knocked by a 1kg or 10kg hammer until the upper shell and the lower shell are cracked, the hard tag shows plastic fracture (whitening phenomenon exists near the crack and the crack is fractured after plastic deformation) as the hard tag made of new materials, but is not completely brittle fracture (the crack is directly fractured without deformation), the anti-theft requirement can be met, waste is changed into valuable, and the urgent requirement of vast clients on acoustic-Green (Pro-Green) acoustic-magnetic or radio-frequency anti-theft hard tags can be met.

Drawings

Fig. 1 is a schematic structural diagram of an acoustic magnetic or radio frequency anti-theft hard tag, wherein 1 is an upper shell, 2 is a lower shell, 3 is an alarm piece, and 4 is a locking nail.

FIG. 2a is a photo of the acoustic magnetic anti-theft hard tag made of 100% waste ABS plastic and continuously knocked by a 1kg or 10kg hammer until the tag is cracked, and FIG. 2b is a photo of the same hard tag made of brand-new ABS plastic and continuously knocked by a 1kg or 10kg hammer until the tag is cracked.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to specific examples. It will be understood by those skilled in the art that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the examples, the experimental methods used were all conventional methods unless otherwise specified, and the materials, reagents and the like used were commercially available without otherwise specified.

Example 1

100% waste ABS plastic (with the notch impact strength of 7.12kJ/m2) is granulated and then is molded into an upper shell and a lower shell of the acoustic-magnetic anti-theft hard label through a mold, a pin lock core and a 58.1kHz acoustic-magnetic alarm part are assembled, the upper shell and the lower shell are welded into a cavity through ultrasonic welding to form a whole, the acoustic-magnetic anti-theft hard label is obtained, the acoustic-magnetic anti-theft hard label is fixed on the surface of an anvil, and is continuously hammered by a 1kg or 10kg iron hammer until the hard label cracks, at the moment, the hard label shows plastic fracture (whitening phenomenon near the crack and fracture after the crack has plastic deformation) and is not complete brittle fracture (the crack is directly fractured without deformation), and the high-quality regenerated plastic radio-frequency anti-theft hard label meeting the anti-theft requirement is prepared, namely, the Green trend (Pro-Green) acoustic-magnetic anti-theft hard label is prepared.

Example 2

Waste ABS plastic (namely 100 percent of waste ABS plastic with the notch impact strength of 7.12 kJ/m)²) And the brand new ABS plastic is prepared from the following raw materials in parts by weight: mixing and granulating brand-new ABS plastic with the weight ratio of 90:10 to obtain the ABS plastic with the notch impact strength of 8.21kJ/m²The materials are then injected into the upper and lower shells of the acoustic magnetic anti-theft hard tag through a mould, the pin lock core and the 8.1MHz radio frequency alarm piece are assembled,welding an upper shell and a lower shell into a cavity through ultrasonic welding to form a whole, namely obtaining the radio frequency anti-theft hard tag, fixing the radio frequency anti-theft hard tag on the surface of an anvil, continuously pounding the hard tag by using a 1kg or 10kg iron hammer until the hard tag cracks, wherein the hard tag shows plastic fracture (whitening phenomenon exists near a crack and the crack cracks are fractured after plastic deformation) but not complete brittle fracture (the crack is directly fractured without deformation), and the radio frequency anti-theft hard tag which is prepared from high-quality recycled plastics and meets the anti-theft requirement, namely the radio frequency anti-theft hard tag with Green tendency (Pro-Green).

Example 3

Waste ABS plastic (namely 100 percent of waste ABS plastic with the notch impact strength of 7.12 kJ/m)²) And the brand new ABS plastic is prepared from the following raw materials in parts by weight: mixing and granulating brand-new ABS plastic in a weight ratio of 80:20 to obtain the product with the notch impact strength of 9.29kJ/m²The materials are then injected into an upper shell and a lower shell of the acoustic-magnetic anti-theft hard tag through a mold, a pin lock core and a 58.5kHz acoustic-magnetic alarm piece are assembled, the upper shell and the lower shell are welded into a cavity through ultrasonic welding to form a whole, the acoustic-magnetic anti-theft hard tag is obtained, the acoustic-magnetic anti-theft hard tag is fixed on the surface of an anvil, a 1kg or 10kg iron hammer is used for continuously pounding the hard tag until the hard tag cracks, at the moment, the hard tag shows plastic fracture (whitening phenomenon exists near the crack and the crack cracks are fractured after plastic deformation) and is not completely brittle fracture (the crack is fractured directly without deformation), and the high-quality recycled plastic acoustic-magnetic anti-theft hard tag which meets the anti-theft requirement is prepared, namely, the acoustic-magnetic anti-theft hard tag which is Green and prone (Pro-Green).

Example 4

Waste ABS plastic (namely 100 percent of waste ABS plastic with the notch impact strength of 7.12 kJ/m)²) And the brand new ABS plastic is prepared from the following raw materials in parts by weight: mixing and granulating brand-new ABS plastic with the weight ratio of 70:30 to obtain the product with the notch impact strength of 10.38kJ/m²The materials are then injected into an upper shell and a lower shell of the acoustic-magnetic anti-theft hard tag through a mould, a pin lock core and an 8.3MHz radio frequency alarm piece are assembled, the upper shell and the lower shell are welded into a cavity through ultrasonic welding to form a whole, the radio frequency anti-theft hard tag is obtained (the structural schematic diagram is shown in figure 2), and the radio frequency anti-theft hard tag is fixedThe method is characterized in that the method is fixed on the surface of an anvil, 1kg or 10kg of iron hammers are used for continuously pounding until a hard label cracks, at the moment, the hard label shows plastic fracture (whitening phenomenon exists near the crack and the crack is fractured after plastic deformation is generated), and the hard label is not completely brittle fracture (the crack is directly fractured without deformation), so that the anti-theft requirement of the high-quality regenerated plastic radio-frequency anti-theft hard label is met, and the high-quality regenerated plastic radio-frequency anti-theft hard label meeting the anti-theft requirement, namely a Green trend (Pro-Green) radio-frequency anti-theft hard label, is prepared.

Example 5

Waste ABS plastic (namely 100 percent of waste ABS plastic with the notch impact strength of 7.12 kJ/m)²) And the brand new ABS plastic is prepared from the following raw materials in parts by weight: mixing and granulating brand-new ABS plastic with the weight ratio of 51:49 to obtain the ABS plastic with the notch impact strength of 12.45kJ/m²The materials are then injected into the upper and lower shells of the acoustic magnetic anti-theft hard tag through a mould, the pin lock core and the 8.2MHz radio frequency alarm piece are assembled, the upper and lower shells are welded into a cavity through ultrasonic welding to form a whole, namely, the radio frequency anti-theft hard tag (the structure diagram is shown in figure 2) is obtained, the radio frequency anti-theft hard tag is fixed on the surface of an anvil, the hammer of 1kg or 10kg is used for continuously pounding until the hard tag cracks, at the moment, the hard tag shows plastic fracture (the phenomenon of whitening near the crack and the crack breaks after plastic deformation), the high-quality recycled plastic radio frequency anti-theft hard tag is not completely brittle fracture (the fracture is directly fractured without deformation), and meets the anti-theft requirement of the high-quality recycled plastic radio frequency anti-theft hard tag, and the high-quality recycled plastic radio frequency anti-theft hard tag meeting the anti-theft requirement, namely a Green inclined (Pro-Green) radio frequency anti-theft hard tag, is prepared.

Example 6

Waste ABS plastic (namely 100 percent of waste ABS plastic with the notch impact strength of 7.12 kJ/m)²) And the brand new ABS plastic is prepared from the following raw materials in parts by weight: mixing and granulating brand new ABS plastic in a weight ratio of 1:99 to obtain the ABS plastic with the notch impact strength of 17.98kJ/m²The materials are injected into an upper shell and a lower shell of the acoustic-magnetic anti-theft hard tag through a mould, a pin lock core and a 57.5kHz acoustic-magnetic alarm piece are assembled, the upper shell and the lower shell are welded into a cavity through ultrasonic welding to form a whole, and the acoustic-magnetic anti-theft hard tag is obtained (the structural schematic diagram is shown in the figure)2), fixing the acoustic-magnetic anti-theft hard tag on the surface of an anvil, continuously pounding the hard tag by using a 1kg or 10kg hammer until the hard tag cracks, wherein the hard tag shows plastic fracture (whitening phenomenon exists near the crack and the crack fractures after plastic deformation exists), but not complete brittle fracture (the crack fractures directly without deformation), which indicates that a high-quality recycled plastic acoustic-magnetic anti-theft hard tag meeting the anti-theft requirement, namely a Green trend (Pro-Green) acoustic-magnetic anti-theft hard tag, is prepared.

Example 7

Firstly, putting nitrile rubber into an internal mixer, mixing for 5min at 80 ℃, taking out, heating the internal mixer to 165 ℃, adding the nitrile rubber and styrene, mixing for 1min, adding Glycidyl Methacrylate (GMA), mixing for 1min, finally adding an initiator dicumyl peroxide (DCP), mixing for 5min, and taking out to obtain NBR-g- (GMA-co-St), wherein the weight ratio of the nitrile rubber to the glycidyl methacrylate to the styrene to the initiator is 188:6:6: 0.3; drying 100 percent of waste ABS plastic (the notch impact strength is 7.12 kJ/m)²) And performing reactive extrusion on the crushed NBR-g- (GMA-co-St) by a double-screw extruder, setting the temperature of each section of the extruder between 180 ℃ and 230 ℃, setting the rotating speed of a main engine at 60r/min and setting the feeding frequency at 2.5Hz, wherein the mass fraction of the NBR-g- (GMA-co-St) is 6 percent, and then granulating by a granulator to obtain the product with the notch impact strength of 18.0kJ/m²The materials are then injected into an upper shell and a lower shell of the acoustic-magnetic anti-theft hard tag through a mold, a pin lock core and a 57.9kHz acoustic-magnetic alarm piece are assembled, the upper shell and the lower shell are welded into a cavity through ultrasonic welding to form a whole, the acoustic-magnetic anti-theft hard tag (the structural schematic diagram is shown in figure 2) is obtained, the acoustic-magnetic anti-theft hard tag is fixed on the surface of an anvil, a 1kg or 10kg iron hammer is used for continuously pounding the acoustic-magnetic anti-theft hard tag until the hard tag cracks, at the moment, the hard tag shows plastic fracture (whitening phenomenon near the crack and fracture after plastic deformation of the crack) and is not complete brittle fracture (the crack directly breaks without deformation), and the high-quality recycled plastic acoustic-magnetic anti-theft hard tag meeting the anti-theft requirements is prepared, namely, the Green trend (Pro-Green) acoustic-magnetic anti-theft hard tag is obtained.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the protection scope of the present invention, and although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.