Manufacturing method of eco-friendly resin composition and engine cover containing the same

Abstract

The present invention relates to an eco-friendly resin composition comprising a recycled polyamide resin according to one embodiment of the invention and an engine cover manufactured therefrom, wherein the composition comprises 25 to 45 weight% of recycled polyamide resin, 35 to 55 weight% of new nylon resin, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam, and wherein the recycled polyamide resin is derived from discarded nylon fishing nets.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing an eco-friendly resin composition and an engine cover comprising the same, and more specifically, to a method for collecting lost nylon waste fishing nets and recycling them into a recycled raw material for an engine cover, which is an automotive part, through washing, crushing, cutting, pressurizing, heating, and a compounding extruder. Background Technology

[0002] Polyester, nylon, polyethylene, and PVC are used as materials for fishing nets, but since the 1970s, most fishing net materials have been shifting toward the use of nylon polymers.

[0003] Nylon fishing nets are typically discarded after two to three years of use, but about 5 to 20 percent of them are lost underwater. Since these lost nets are left undisturbed for long periods, they pollute the underwater environment and cause aquatic life to become ill, thereby destroying the aquatic ecosystem. In particular, endocrine disruptors released from discarded nylon fishing nets also contribute to the decline in fish catches.

[0004] As a technology to resolve the problem of lost nylon fishing nets as described above, there is a technology to produce biodegradable fishing nets using biodegradable polymers such as polybutylene succinate (PBS). However, even if the fishing nets are decomposed by adding biodegradable polymers, the various additive components added to artificially manufactured plastics inevitably have an adverse effect on the marine or river environment and ecosystem. Therefore, collecting and recycling the fishing nets is ultimately the safest method.

[0005] Meanwhile, in the recycling of nylon waste fishing nets, significant degradation and fluctuation in molecular weight are inevitable during the process of processing the recycled material into various component materials. Furthermore, the recycled material often contains small amounts of polyester and polyethylene fibers in addition to nylon; these fibers are not properly mixed during the processing, thereby degrading the physical properties of the recycled material. Consequently, there is a problem in that a significant amount of time and manpower is consumed to individually identify materials with such physical property issues arising from the processing.

[0006] Therefore, to minimize the impact of non-nylon fibers mixed in the aforementioned recycled material on its physical properties, it is necessary to use additives to enhance usability. Traditionally, nylon resin has been widely used as a material for automotive parts by incorporating reinforcing materials such as glass fibers. In other words, technology is required to determine the content and type of reinforcing material to match the required physical properties of the target part, and to select and formulate the necessary additives.

[0007] Thus, the present invention aims to provide a resin composition for use as an engine cover for automobiles by mixing a reinforcing agent and an additive with waste nylon fishing nets to regenerate them into recycled nylon material.

[0008] Next, we will briefly explain the prior art existing in the field to which the technology of the present invention belongs, and then explain the technical details that the present invention aims to achieve differently from the said prior art.

[0009] First, Korean Registered Patent No. 10-1130461 (published on April 12, 2012) relates to a method for regenerating waste nylon fishing nets and recycled nylon long fibers. More specifically, it relates to a method for regenerating waste nylon fishing nets that allows for the recovery of waste nylon fishing nets as raw materials by depolymerizing them without dismantling or sorting, and enables repeated regeneration, a method for manufacturing recycled nylon long fibers using the same, and recycled nylon long fibers manufactured therefrom. The above prior art is similar to the present invention in that it relates to a method for regenerating waste nylon fishing nets, but it differs from the present invention in that it relates to a method for regenerating waste nylon fishing nets by depolymerizing them, unlike the regeneration method using a compounding process as in the present invention.

[0010] Regarding nylon recycling technology using a compounding process similar to the present invention, there is Korean Registered Patent No. 10-0666794 (published on January 9, 2007). The prior art relates to a resin composition using waste nylon resin and a method for manufacturing the same. More specifically, it relates to mixing waste nylon resin, nylon-based resin, glass fiber, inorganic filler, and various additives in an optimal ratio to achieve excellent heat resistance and mechanical strength, enable the realization of excellent molded products, and improve the physical properties of the resin to a level that allows for recycling. Although the prior art shares some similarities with the present invention in that it describes a technology regarding additives mixed to improve physical properties when recycling waste nylon resin through a compounding process, it still had the problem of low physical properties, making it difficult to apply for automotive parts.

[0011] In Korean Registered Patent No. 10-0401768 (published on October 17, 2003), a patent was registered for a composition with excellent vibration damping properties by compounding glass fiber and mica with 100 parts by weight of nylon and molding an engine cover. In addition, in Korean Registered Patent No. 10-0527945 (published on November 9, 2005), a patent was registered for use as an automobile engine cover using a resin composition that reinforces long-term heat resistance by adding a hydrotalcite-based long-term heat-resistant agent and nanoclay to nylon resin. In Korean Registered Patent No. 10-0828654 (published on May 9, 2008), a composition for use as an engine cover with excellent heat resistance was filed by compounding inorganic fillers such as glass bubbles and talc with nylon 6 resin.

[0012] The aforementioned patents related to engine covers do not utilize recycled fishing nets, and no composition has been developed using recycled fishing nets with physical properties tailored for use as engine covers. Prior art literature

[0013] Korean Registered Patent No. 10-1130461 (Published Apr. 12, 2012) Korean Registered Patent No. 10-0666794 (Published Jan. 09, 2007) Korean Registered Patent No. 10-0401768 (Published Oct. 17, 2003) Korean Registered Patent No. 10-0527945 (Published Nov. 09, 2005) Korean Registered Patent No. 10-0828654 (Published May 09, 2008) The problem to be solved

[0014] The present invention was created to solve the aforementioned problem, and aims to provide a resin composition recycled from nylon waste fishing nets and a method for manufacturing the same, which can regenerate nylon waste fishing nets into recycled materials that serve as materials for high-value-added parts such as engine covers, intake manifolds, and radiator grilles, by utilizing a compounding process that is relatively simple and consumes less energy compared to a large-scale nylon recycling chemical process that requires a large amount of energy. means of solving the problem

[0015] A resin composition manufactured by recycling a nylon waste fishing net according to one embodiment of the present invention is characterized by comprising 25 to 45 weight% of recycled nylon waste fishing net material, 35 to 55 weight% of new nylon resin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam.

[0016] In addition, as one embodiment, the nylon resin novel is characterized as being nylon 6, nylon 66, or a mixture thereof.

[0017] In addition, a method for manufacturing a resin composition recycled from nylon waste fishing nets according to another embodiment of the present invention comprises a pretreatment process of washing the nylon waste fishing net and cutting it into pieces 10 to 30 cm in size, and a process of manufacturing the nylon waste fishing net cut through the pretreatment step into pelletized nylon recycled material, wherein the compounding extrusion process comprises the step of manufacturing nylon recycled material by pressurizing and heating the nylon waste fishing net cut through the pretreatment step to melt it, and then feeding it into the feed section of an extruder to pelletize it; the step of feeding 25 to 45 weight% of nylon recycled material, 35 to 55 weight% of nylon resin virgin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam into the compounding extruder; and the step of heating, melting, and mixing the fed materials. It is characterized by including a step of compounding to form pellets and discharging them.

[0018] In one embodiment of the present invention, in the compounding process, one or more additives selected from plasticizers, antioxidants, heat stabilizers, UV stabilizers, flame retardants, lubricants, antistatic agents, impact modifiers, crosslinking agents, colorants, and nucleating agents may be further introduced into the compounding machine as material property aids.

[0019] In one embodiment of the present invention, the temperature during compounding may be in the range of 250 to 270°C. Effects of the invention

[0020] The present invention relates to a resin composition recycled from discarded nylon fishing nets and a method for manufacturing the same. By regenerating discarded nylon fishing nets through cutting and washing, and then heating, melting, and mixing them with new nylon resin, glass fibers, inorganic fillers, and additives in a compounding process to form a recycled nylon resin that serves as a base material for high-value-added parts such as automotive components like engine covers, intake manifolds, and radiator grilles, discarded nylon fishing nets can be recycled at a lower cost compared to conventional large-scale chemical processes that consume large amounts of energy. Furthermore, by securing such recycling technology, environmental preservation can be achieved while creating new added value through recycled materials. In addition, manufacturing component materials such as automotive parts using these recycled materials can lower the unit cost of parts and contribute to global environmental protection, resource conservation, and CO2 reduction. Brief explanation of the drawing

[0021] FIG. 1 is a block diagram illustrating a nylon waste fishing net recycling process according to one embodiment of the present invention. Specific details for implementing the invention

[0022] Hereinafter, preferred embodiments of a resin composition recycled from nylon waste fishing nets and a method for manufacturing the same according to the present invention will be described in detail with reference to the attached drawings so that a person skilled in the art to which the present invention pertains can easily practice the present invention.

[0023] In each drawing of the present invention, the sizes or dimensions of the structures are depicted enlarged or reduced compared to the actual size to ensure clarity of the invention, and known components are omitted to reveal characteristic configurations, so the invention is not limited to the drawings.

[0024] In describing the principles of a preferred embodiment of the present invention in detail, if it is determined that a specific description of related known functions or configurations could unnecessarily obscure the essence of the present invention, such detailed description is omitted.

[0025] In addition, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0026] The present invention relates to a resin composition obtained by collecting and recycling nylon waste fishing nets and a method for manufacturing the same. The resin composition of the present invention is characterized by comprising 25 to 45 weight% of recycled nylon waste fishing net material, 35 to 55 weight% of new nylon resin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam.

[0027] Here, the nylon resin new material refers to the new material after polymerization, not recycled as nylon 6, nylon 66, or a mixture thereof.

[0028] In addition, the method for manufacturing a resin composition recycled from nylon waste fishing nets according to the present invention comprises a pretreatment process of washing the nylon waste fishing net and cutting it into pieces 10 to 30 cm in size, and a regeneration pelletization process of manufacturing the nylon waste fishing net cut through the pretreatment step into pelletized nylon recycled material. The regeneration pelletization process refers to a process of melting the nylon waste fishing net cut through the pretreatment step by applying pressure and heating, and then feeding it into the feed section of an extruder to form regeneration pellets. The compounding process is characterized by comprising the steps of: introducing 25 to 45 weight% of pelletized recycled nylon material, 35 to 55 weight% of new nylon resin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam into the interior of a compounding extruder; and heating, melting, and mixing the introduced material to compound and discharge it.

[0029] The present invention will be described in more detail below with reference to the drawings.

[0030] FIG. 1 is a block diagram illustrating a nylon waste fishing net recycling process according to one embodiment of the present invention.

[0031] As illustrated in FIG. 1, the nylon waste fishing net recycling process of the present invention is largely composed of a nylon recycling process for pre-treating waste fishing nets and a compounding process.

[0032] The nylon recycling process for pre-treating the above-mentioned waste fishing nets involves collecting waste fishing nets that are collected from underwater or discarded after use, cutting them into sizes of 10 to 30 cm so that they can be used in the next compounding process, and performing pre-treatment before recycling the nylon waste fishing nets, such as washing the waste fishing nets to prevent foreign substances from mixing into the recycling process.

[0033] Nylon waste fishing net pieces, cut and washed to a size of 10 to 30 cm through the above waste fishing net pretreatment process, are supplied to the above compounding process.

[0034] In the compounding process above, a process is performed in which nylon waste fishing net pieces, which are primarily cut in the waste fishing net pretreatment process, are pressurized and heated to sufficiently melt them so that a solid bed can be formed that can be fed into the feed section of a recycling extruder.

[0035] In other words, the cut pieces of waste fishing nets are uniformly mixed and melted under pressure and heat, and then fed into the feed section of the recycling extruder. By forming the resin into a solid bed using a pressurized and heated method, there is an advantage in being able to process various types of shredded materials into the recycling extruder. Film or fiber forms are difficult to feed directly into the feed section of the recycling extruder, and it is also difficult to feed shredded materials into the feed section when they are fine and have a low apparent specific gravity, or when they are large in size. By pre-melting the resin using a pressurized and compressed method and feeding it into the recycling extruder, stable production of recycled materials is possible regardless of the shape of the shredded materials.

[0036] The recycled nylon waste fishing net material manufactured as described above undergoes a compounding extrusion step involving heating, melting, and mixing after the addition of new nylon resin and additives to reinforce physical properties.

[0037] At this time, the components fed into the compounding extruder include nylon resin virgin material containing nylon 6, nylon 66, or a mixture thereof, glass fiber, and inorganic filler. If the content of nylon resin virgin material is less than 35 weight%, problems arise such as reduced compounding performance and mechanical durability strength, and if it exceeds 55 weight%, problems arise such as increased costs and reduced efficiency in recycling waste nylon fishing nets.

[0038] In addition, glass fibers play a role in improving the mechanical strength of recycled nylon, but if the content is less than 5 weight percent, the improvement in mechanical strength is not significant, and if it exceeds 30 weight percent, there is a problem that it may cause difficulties in molding when producing products using recycled nylon as a raw material.

[0039] In addition, the inorganic filler includes one or more selected from carbon black, calcium carbonate, talc, diatomaceous earth, activated clay, acid clay, hydrated lime, cement, silica fume, clay, mica, fly ash, and bentonite. If the content is less than 5 weight%, mechanical strength may decrease, causing problems in maintaining the shape stably, and if it exceeds 20 weight%, there may be problems with the physical properties as a raw material for recycled nylon deteriorating.

[0040] That is, the components fed into the compounding extruder are preferably in the range of 25 to 45 weight% of recycled nylon fishing nets, 35 to 55 weight% of new nylon resin, 5 to 30 weight% of glass fibers, and 5 to 20 weight% of inorganic fillers.

[0041] Since recycled resin has undergone thermal history, its molecular weight decreases and various types of decomposition or gelation reactions occur. Therefore, when recycled materials are used, a degradation of various physical properties occurs. In particular, it often significantly affects long-term durability properties (usage characteristics). When 100% of the nylon waste fishing net recycled material used in the present invention is used, the long-term durability properties are drastically reduced, making it unsuitable for application as an engine cover material.

[0042] In addition, the fishing net is a nylon fiber grade with a high specific viscosity of approximately 2.9. This material has a high molecular weight, making it unsuitable for injection molding applications. In particular, when the injection-molded product is a large part such as an engine cover, this level of viscosity poses a problem for moldability. Methods to solve this problem include adding additives to control molecular weight or increasing fluidity during the compounding process. It is known that metal salt-based lubricants such as caprolactone or calcium stearate (Ca-St) are used, or decomposition agents such as peroxides are used. However, peroxides have the problem of not being able to fully control their decomposition reactions to reproduce the desired physical properties.

[0043] Accordingly, in this invention, research was conducted to control the molecular weight of recycled nylon using an additive having carboxyl groups (dicarboxylic acid) at both ends.

[0044] Among these, experiments were conducted by adding straight-chain difunctional carboxylic acids with 12 to 16 carbon atoms. As a result of the experiment, dodecanedioic acid (DDA) with 12 carbon atoms obtained the best molecular weight control effect.

[0045] In addition, recycled fishing nets have a high molecular weight, but their mechanical properties are reduced due to thermal history and decomposition during use. This problem can be addressed by adding ε-caprolactam, a monomer of nylon 6, to induce a polymerization reaction during the compounding process, thereby compensating for the properties that may deteriorate during the regeneration process.

[0046] Adding the above straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms in the range of 0.1 to 3 weight% and ε-caprolactam in the range of 0.5 to 5 weight% can compensate for the physical properties of the recycled material and improve flowability, thereby providing physical properties suitable for injection molding.

[0047] Other commonly used additives may include one or more of the following: plasticizers to increase the flexibility, processability, or expandability of the resin; antioxidants to prevent the loss of the intrinsic properties of nylon due to oxidation; heat stabilizers to inhibit the thermal decomposition of nylon; UV stabilizers to prevent the decomposition of nylon by ultraviolet rays, which causes discoloration or loss of mechanical properties; flame retardants to reduce flammability; lubricants to facilitate the flow of metal surfaces in contact with nylon during the compounding process; antistatic agents to suppress the generation of static electricity on the nylon surface; impact modifiers to improve impact resistance; crosslinking agents used in crosslinking reactions; colorants composed of pigments and dyes; and nucleating agents to promote the crystallization rate of the polymer, refine the crystal size to improve transparency, and increase the crystallization rate.

[0048] The recycled nylon resin compounded through the steps described above is cut into recycled nylon in a pelletized state.

[0049] The present invention will be explained in more detail through the following examples.

[0050] Examples 1 to 5

[0051] Recycled nylon waste fishing nets, new nylon resin (Nylon 6, Hyosung Toplan 1101), glass fiber, and inorganic filler (talc) were compounded after adding DDA and caprolactam monomer (ε-caprolactam). Antioxidants and lubricants were basically used in amounts of 1 wt% or less. As shown in Table 1 below, recycled nylon was manufactured using a compounding extruder with a cylinder temperature of 250 ℃, L / D=40, and a diameter of 60 mm, and specimens were manufactured through an injection molding process at 250 ℃ and 8 oz.

[0052] Comparative Examples 1 to 6

[0053] Recycled nylon waste fishing net material, new nylon resin material, glass fiber, inorganic filler, and additives were mixed as shown in Table 1 below, and recycled nylon resin was manufactured through the compounding process as described above, and specimens were manufactured through an injection molding process.

[0054] division Recycled Nylon Fishing Nets (Weight %) New Nylon 6 Resin (Weight%) Glass fiber (weight%) Talc (weight%) DDA (weight%) ε-Caprolactam (whether %) Example 1 39.6 39.6 11.9 7.9 0.3 0.7 Example 2 44.0 36.7 11.0 7.3 0.3 0.7 Example 3 30.4 49.5 11.4 7.6 0.3 0.7 Example 4 39.1 39.1 11.7 7.8 1.6 3.7 Example 5 37.9 37.9 11.4 7.6 1.5 3.8 Comparative Example 1 40.0 40.0 12.0 8.0 - - Comparative Example 2 39.7 39.7 11.9 7.9 - 0.8 Comparative Example 3 39.9 39.9 12.0 8.0 0.3 - Comparative Example 4 51.2 32.0 9.6 6.4 0.2 0.6 Comparative Example 5 36.9 36.9 11.1 7.4 0.3 7.4 Comparative Example 6 37.6 37.6 11.3 7.5 5.2 0.8

[0055] Exam content

[0056] Tensile strength, flexural strength, Izod impact strength, HDT heat distortion temperature, fluidity, and long-term use characteristics were measured for a material developed as an engine cover material by compounding using recycled nylon fishing nets from Examples 1 to 5 and Comparative Examples 1 to 6.

[0057] Test Method

[0058] Measurements were taken using the method shown in Table 2 below, and target values ​​were set based on Hyundai Motor Company’s material specification MS211-60 for engine cover materials. Here, tensile strength followed ASTM D638, flexural strength followed ASTM D790, Izod impact strength followed ASTM D256, and HDT heat distortion temperature followed ASTM D648. For long-term service characteristics, the above tensile strength, flexural strength, Izod impact strength, and HDT heat distortion temperature were measured at 140°C for 1,000 hours. For long-term service characteristics, a tensile strength value of 80% or more of the initial measured value was set as the standard normal value.

[0059] Target figures

[0060] Performance indicators unit target Test standards tensile strength Kgf / cm 2 950 or more ASTM D638 Flexural strength Kgf / cm 2 1,500 or more ASTM D790 Izod impact strength Kgf.cm / cm 3 or more ASTM D256 HDT heat distortion temperature ℃ 180 or more ASTM D648 liquidity 235 ℃, 2.16 kgf g / 10 min 15 or more - Long-term use characteristics 140 ℃, 1000 h Maintain tensile strength of 80% or more -

[0061] Test results

[0062] division Tensile strength Kgf / cm 2 Flexural strength Kgf / cm 2 Izod impact strength Kgf.cm / cm HDT Heat Distortion Temperature ℃ Flowability, 235℃, g / 10 min Long-term use characteristics 140℃, 1000 h Example 1 950 1570 4 181 15 Maintain 83% Example 2 960 1550 4.5 182 16 Maintain 83% Example 3 980 1530 4.5 183 18 Maintain 90% Example 4 955 1550 4.5 183 18 Maintain 85% Example 5 960 1500 4.5 181 16 Maintain 83% Comparative Example 1 970 1550 3.2 170 6 Maintain 55% Comparative Example 2 980 1570 3.5 177 10 Maintain 66% Comparative Example 3 980 1580 4.2 180 14 Maintain 80% Comparative Example 4 940 1480 2.8 182 15 Maintain 83% Comparative Example 5 900 1550 4.0 184 20 Maintain 70% Comparative Example 6 900 1500 3.2 173 24 Maintain 70%

[0063] Table 2 above is a table showing target values ​​in the physical property evaluation of recycled nylon material according to the present invention, and Table 3 is a table showing experimental results according to Examples 1 to 5 and Comparative Examples 1 to 6 above.

[0064] As shown in the test results of Table 3 above, Examples 1 to 5 all satisfy the target values ​​for tensile strength, flexural strength, Izod impact strength, HDT heat distortion temperature, and long-term use characteristics. In particular, the flow characteristics also show results similar to or better than those when using new material, with a flow rate of 15 g / 10 min or higher.

[0065] Meanwhile, looking at the comparative test results in Table 3 above, it can be seen that when the content of recycled nylon fishing net material is mixed at 100 wt% or more (Comparative Example 1), the mechanical properties approach the lower limit of the target value, while the HDT heat resistance temperature does not reach the target value. In terms of long-term use properties, it can be seen that it reaches approximately 55% of the target value. Furthermore, the flow characteristics are less than 15 g / 10 min, indicating that it would be difficult to mold large injection-molded parts. Consequently, it was found to be unsuitable for use as a material for automotive parts. As the content of the recycled material is reduced, long-term use characteristics improve along with an increase in the HDT heat resistance temperature. When the content is 50% or less, it can be seen that the properties approximate the target values.

[0066] The examples in Table 3 show the physical properties when DDA, which has two carboxyl groups, and caprolactam, a monomer of nylon 6, are added to improve physical properties when the content of recycled material is mixed at 50% by weight or more. It shows that while mechanical strengths such as tensile strength, flexural strength, and impact strength remain largely unchanged, the heat distortion temperature has increased. Furthermore, long-term use characteristics are also improved, showing a property retention rate of over 80%. This implies that the addition of DDA and caprolactam, a monomer of nylon 6, acts as a fluidity enhancer during compounding, thereby increasing the molecular weight of the nylon resin. This increase in molecular weight demonstrates that target physical properties can be achieved even when using a large amount (50%) of recycled waste fishing net material.

[0067] In other words, it can be seen that for the composition of the nylon recycled material to satisfy the target values ​​shown in Table 2 above, it is preferable to use 50 weight% or less of recycled nylon fishing net material. Furthermore, it shows that adding small amounts of DDA and caprolactam can produce a material with improved properties that surpass the target properties. It can also be seen that 50 weight% or more of recycled nylon fishing net material can be used.

[0068] Although the present invention has been described above with reference to embodiments illustrated in the attached drawings, this is merely illustrative, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible therefrom. Accordingly, the technical scope of protection of the present invention should be determined by the following claims. Explanation of the symbols

[0070] 100 : Pretreatment process 200 : Compounding process

Claims

Claim 1 A polyamide recycled resin composition for a compounding process, comprising 25 to 45 weight% of polyamide recycled resin, 35 to 55 weight% of nylon resin virgin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of inorganic filler, and as a modifier for controlling the physical properties of the recycled resin, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms and 0.5 to 5 weight% of ε-caprolactam; wherein the polyamide recycled resin is derived from nylon waste fishing nets. Claim 2 A polyamide recycled resin composition for a compounding process according to claim 1, characterized in that the nylon waste fishing net is nylon 6, nylon 66, or a mixture thereof. Claim 3 A method for manufacturing a polyamide recycled resin composition for a compounding process comprises: a pretreatment process of washing a nylon waste fishing net and cutting it into pieces 10 to 30 cm in size; and a compounding process of manufacturing the nylon waste fishing net cut through the pretreatment step into pelletized nylon recycled material; wherein the compounding process comprises the step of: pressurizing and heating the nylon waste fishing net cut through the pretreatment step to melt it and feeding it into the feed portion of a regeneration extruder to produce a waste fishing net recycled material; and feeding 25 to 45 weight% of the nylon waste fishing net recycled material, 35 to 55 weight% of the nylon resin virgin material, 5 to 30 weight% of glass fiber, 5 to 20 weight% of an inorganic filler, 0.1 to 3 weight% of a straight-chain difunctional carboxylic acid having 12 to 16 carbon atoms, and 0.5 to 5 weight% of ε-caprolactam into the interior of a compounding extruder. A method for manufacturing a polyamide recycled resin composition for a compounding process, characterized by comprising the steps of: heating, melting, and mixing an input material to compound it, and pelletizing and discharging it. Claim 4 A method for manufacturing a polyamide recycled resin composition for a compounding process, characterized in that, in paragraph 3, one or more additives selected from plasticizers, antioxidants, heat stabilizers, UV stabilizers, flame retardants, lubricants, antistatic agents, impact modifiers, crosslinking agents, colorants, and nucleating agents are further introduced into the compounding machine as physical property aids. Claim 5 A method for manufacturing a polyamide recycled resin composition for a compounding process, characterized in that, in paragraph 3, the temperature during compounding extrusion is in the range of 250 to 270℃.

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