Method for preparing packaging material by recycling waste artificial boards

Abstract

The invention discloses a method for preparing a packaging material by recycling waste artificial boards, and belongs to the technical field of packaging materials. The method for preparing the packaging material by recycling the waste artificial boards comprises the following steps that the waste artificial boards are crushed and screened, and board particles are obtained; mixing the resin particles with a foaming agent to obtain a mixture; uniformly mixing the plate particles, the mixture, a binder and a lubricant to obtain a premix; the premix is added into a molding press to be subjected to mold pressing, and a plate blank is obtained; the plate blank is subjected to standing, cooling and drying, and a secondary plate is obtained; and the secondary plate is cut, and the cut secondary plate is used as a packaging material. By the adoption of the method for preparing the packaging material through recycling of the waste artificial boards, the problems that existing waste boards are high in treatment cost, and packaging boards are low in strength and difficult to degrade can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of packaging materials, and in particular to a method for preparing packaging materials by recycling waste artificial boards. Background Art

[0002] Currently, panel furniture uses a large number of artificial boards, including medium-density boards, high-density boards, solid wood particle boards, multi-layer boards, etc. Before cutting, furniture companies will use nesting software to perform layout calculations to achieve a higher board utilization rate. At present, the general board utilization rate in the industry is between 85% and 92%, which will form a certain ratio of surplus or waste artificial boards. In the cutting process, furniture companies use electronic saws and large-board nesting equipment to cut materials. After cutting, the remaining or waste artificial boards will be collected and concentrated.

[0003] At present, discarded boards are cut or crushed into particles. One way is to treat them as garbage, and the other is to recycle them. However, both methods require transportation to centralized processing points for processing or recycling, which makes the cost of board processing relatively high.

[0004] In the packaging process, furniture companies use existing foam boards to fill the remaining space and protect the finished furniture panels. Foam has the characteristics of low cost, but when the finished panels are circulated to the end customers, they are recycled as hazardous waste. In some urban and rural areas or rural areas, they are directly discarded as garbage in the natural environment, which is difficult to degrade naturally and causes great pollution to the environment. In addition, the strength of the existing foam board is relatively high, and the protective effect on furniture panels is relatively poor. Summary of the invention

[0005] The purpose of the present invention is to provide a method for recycling waste artificial board materials to prepare packaging materials, so as to solve the problems of high cost of waste board treatment, low strength of packaging board materials and difficulty in degradation.

[0006] To achieve the above object, the present invention provides a method for recycling waste artificial board materials to prepare packaging materials, comprising the following steps: S1, crushing and screening the waste artificial board to obtain board particles; S2, mixing the resin particles with the foaming agent to obtain a mixture; S3, mixing the plate particles, the mixture, the binder and the lubricant uniformly to obtain a premix; S4, adding the premix into a molding machine for molding to obtain a slab; S5, standing, cooling and drying the slab to obtain a secondary plate; S6. Cut the secondary board material and use the cut secondary board material as packaging material.

[0007] Preferably, in S1, the thickness of the waste artificial board is 6mm-35mm, the waste artificial board includes medium-density fiberboard, high-density fiberboard, particleboard, solid wood sandwich panel, and the crushing method includes mechanical crushing and thermal treatment crushing.

[0008] Preferably, in S1, the particle size of the plate particles is 1 mm-2 mm.

[0009] Preferably, in S2, the resin particles are one of polystyrene particles, polyurethane particles, polyvinyl chloride particles, and polylactic acid foamed particles; the foaming agent is an azo foaming agent; and the mass percentage of the foaming agent in the mixture is 4%-6%.

[0010] Preferably, in S3, the mass percentages of the components in the premix are: 45%-55% of plate particles, 30%-35% of mixed material, 15%-20% of binder, and 3%-5% of lubricant.

[0011] Preferably, in S3, the binder is starch adhesive, urea-formaldehyde glue or white latex, and the lubricant is calcium stearate.

[0012] Preferably, in S4, the heating temperature in the molding machine is 100° C.-200° C., and the insulation time is 5 min-10 min.

[0013] Preferably, in S5, the slab is left standing at room temperature for not less than 2 hours.

[0014] Preferably, in S6, when the secondary board material is cut and used as a packaging material for finished furniture board materials, a protective layer is provided between the cut surface of the secondary board material and the finished furniture board material.

[0015] Preferably, before S2, the process also includes soaking the sheet material particles in a flame retardant liquid for 1 to 2 hours; after the soaking, the sheet material particles are dried until the moisture content of the sheet material particles is below 5%.

[0016] The advantages and positive effects of the method for preparing packaging materials by recycling waste artificial boards described in the present invention are: the present invention forms a plate-like structure by foaming resin particles, which is conducive to reducing the density and weight of secondary boards, and improving the flexibility of the boards to meet packaging needs. The board particles in the secondary boards are the main components, which have the characteristics of natural degradation, reduce environmental pollution, and realize the recycling and reuse of waste artificial boards. The packaging materials mainly use waste artificial boards as the main raw materials, which reduces the cost of packaging materials.

[0017] The technical solution of the present invention is further described in detail below through embodiments. DETAILED DESCRIPTION

[0018] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application. In the event of any inconsistency, the meaning described in this specification or the meaning derived from the contents recorded in this specification shall prevail. In addition, the terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application. In order to accurately describe the technical content in this application and to accurately understand the present invention, the following explanations or definitions are given to the terms used in this specification before describing the specific embodiments: The embodiments of the present invention are described in detail below.

[0019] A method for recycling waste artificial board materials to prepare packaging materials comprises the following steps: S1. Crushing and screening the waste artificial board to obtain board particles.

[0020] Crushing methods include mechanical crushing and heat treatment crushing. Mechanical crushing is to cut the plate to be crushed into fine particles by high-speed rotating blades to achieve the purpose of crushing. Heat treatment crushing is to heat the plate to be crushed to a high temperature, and then quickly cool the plate after it expands to break it to achieve the purpose of crushing.

[0021] The thickness of waste artificial boards is 6mm-35mm. Waste artificial boards include medium-density fiberboard, high-density fiberboard, particleboard, and solid wood sandwich panels. Waste artificial boards are mainly the remaining or discarded artificial boards from the previous cutting process in panel furniture factories.

[0022] The particle size of the plate particles is 1mm-2mm. Crushing the plate into small particle size plates can facilitate mixing the plate particles with the resin particles.

[0023] S2. Mixing the resin particles with the foaming agent to obtain a mixture.

[0024] The resin particles are one of polystyrene particles, polyurethane particles, polyvinyl chloride particles, and polylactic acid foamed particles. The foaming agent is an azo foaming agent. The resin particles and the foaming agent are first mixed, which is conducive to improving the uniformity of the mixing of the resin particles and the foaming agent.

[0025] The mass percentage of the foaming agent in the mixture is 4%-6%, which ensures that the resin particles can be fully foamed.

[0026] Azo foaming agents are azodicarbonamide or azobisisobutyronitrile. Azodicarbonamide foaming agents decompose rapidly under heating conditions to produce gases such as nitrogen, carbon monoxide and a small amount of carbon dioxide. Thermoplastic resin softens and flows at high temperatures. The large amount of gas produced by the decomposition of the foaming agent causes the sheet to form a uniform pore structure during the molding process, achieving the purpose of foaming and uniform distribution of pores. After maintaining a certain pressure and temperature for a period of time, the sheet is fully shaped and evenly distributed.

[0027] Polylactic acid is a biodegradable thermoplastic polyester synthesized from lactic acid monomers through polycondensation. Lactic acid can be obtained from biomass fermentation such as corn and sugar cane, making polylactic acid renewable. When heated, azobisisobutyronitrile foaming agent decomposes to produce gas to foam PLA. Using polylactic acid particles as foaming resin particles improves the degradability of secondary boards.

[0028] S3, uniformly mixing the plate particles, the mixed material, the binder and the lubricant to obtain a premix.

[0029] The mass percentage of each component in the premix is: 45%-55% of sheet particles, 30%-35% of mixed material, 15%-20% of binder, and 3%-5% of lubricant. By adding binder, the connection strength between sheet particles and resin foam particles is improved, so that the premix can form a good secondary sheet structure. Lubricant can improve the mixing effect of sheet particles, premix and binder, so that sheet particles, premix and binder can be fully mixed, and the uniformity of sheet components is improved.

[0030] The adhesive is starch adhesive, urea-formaldehyde adhesive or white latex.

[0031] Starch adhesives use starch as raw material, which is widely available, inexpensive and environmentally friendly; they are biodegradable and will not pollute the environment. Starch adhesives can give secondary sheets better flexibility to a certain extent, allowing secondary sheets to better meet packaging needs.

[0032] Urea-formaldehyde adhesive has good adhesion, which can improve the connection strength between the board particles and the resin foam particles, which is beneficial to improving the molding effect and strength of the secondary board.

[0033] White glue has good environmental performance. It has a good bonding effect on wood fibers, improves the connection strength between wood fibers and foamed particles, and improves the strength and toughness of secondary boards.

[0034] The lubricant is calcium stearate. Calcium stearate can reduce the friction coefficient between materials, improve fluidity, and improve the mixing uniformity between sheet particles, resin particles and binder. Stearic acid can also act as a release agent, making it easier for the secondary sheet to be removed from the mold after foaming, improving the surface quality of the product and reducing the scrap rate. Calcium stearate can also improve the thermal stability of the foamed sheet and improve the molding effect of the secondary sheet.

[0035] S4, adding the premix into a molding machine for molding to obtain a slab.

[0036] The heating temperature in the molding machine is 100°C-200°C, and the insulation time is 5min-10min.

[0037] At the heating temperature, the resin particles foam under the action of the foaming agent, and the foamed particles are bonded together with the board particles under the action of the binder to form a board structure. The use of resin particles to foam the board particles to form a plate-like structure is conducive to reducing the density and weight of the secondary board, and improving the flexibility of the board to meet the packaging needs. The board particles are the main component of the secondary board, which has the characteristics of natural degradation, reduces environmental pollution, and realizes the recycling and reuse of waste artificial boards.

[0038] S5, the slab is allowed to stand, cool and dry to obtain a secondary plate. The slab is allowed to stand at room temperature for no less than 2 hours. The resin foam material is allowed to mature in the standing state to improve the dimensional stability and flexibility of the secondary plate.

[0039] S6. Cut the secondary board material and use the cut secondary board material as packaging material.

[0040] The cutting of the secondary board can be arbitrarily cut according to the thickness and shape required by the actual finished furniture board. A protective layer is arranged between the cutting surface of the secondary board and the finished furniture board. The protective layer can be artificial foam, artificial plastic film, artificial paper, etc. to prevent the cutting edge of the secondary board from causing wear and scratches on the finished furniture board.

[0041] Before S2, the plate particles are immersed in a flame retardant liquid for 1 to 2 hours. After the immersion is completed, the plate particles are dried until the moisture content of the plate particles is below 5%. After the plate particles are immersed, it is beneficial to improve the flame retardancy of the plate particles and meet the flame retardancy requirements of the packaging material.

[0042] Example 1 A method for recycling waste artificial board materials to prepare packaging materials comprises the following steps: S1. Mechanically crush and sieve the waste artificial board to obtain board particles with a particle size of 1mm-2mm.

[0043] S2. Mixing the resin particles with the foaming agent to obtain a mixture.

[0044] The resin particles are polystyrene particles, the foaming agent is azodicarbonamide, and the mass percentage of the foaming agent in the mixture is 5%.

[0045] S3, uniformly mixing the plate particles, the mixed material, the binder and the lubricant to obtain a premix.

[0046] The mass percentage of each component in the premix is: 51% of plate particles, 30% of mixed material, 15% of binder, and 4% of lubricant.

[0047] The binder is urea-formaldehyde glue and the lubricant is calcium stearate.

[0048] S4, adding the premix into a molding machine for molding to obtain a slab.

[0049] The heating temperature in the molding machine is 120°C and the holding time is 6 minutes.

[0050] S5, the slab is left to stand, cooled and dried to obtain a secondary sheet. The slab is left to stand at room temperature for no less than 2 hours.

[0051] S6. Cut the secondary board material and use the cut secondary board material as packaging material.

[0052] Example 2 A method for recycling waste artificial board materials to prepare packaging materials comprises the following steps: S1. Mechanically crush and sieve the waste artificial board to obtain board particles with a particle size of 1mm-2mm.

[0053] S2. Mixing the resin particles with the foaming agent to obtain a mixture.

[0054] The resin particles are polyvinyl chloride particles, the foaming agent is azodicarbonamide, and the mass percentage of the foaming agent in the mixture is 6%.

[0055] S3, uniformly mixing the plate particles, the mixed material, the binder and the lubricant to obtain a premix.

[0056] The mass percentages of the components in the premix are: plate particles 46%, mixed material 33%, binder 18%, and lubricant 3%.

[0057] The binder is white latex and the lubricant is calcium stearate.

[0058] S4, adding the premix into a molding machine for molding to obtain a slab.

[0059] The heating temperature in the molding machine is 150°C and the holding time is 10 minutes.

[0060] S5, the slab is left to stand, cooled and dried to obtain a secondary sheet. The slab is left to stand at room temperature for no less than 2 hours.

[0061] S6. Cut the secondary board material and use the cut secondary board material as packaging material.

[0062] Example 3 A method for recycling waste artificial board materials to prepare packaging materials comprises the following steps: S1. Mechanically crush and sieve the waste artificial board to obtain board particles with a particle size of 1mm-2mm.

[0063] S2. Mixing the resin particles with the foaming agent to obtain a mixture.

[0064] The resin particles are polylactic acid foamed particles, the foaming agent is azobisisobutyronitrile, and the mass percentage of the foaming agent in the mixture is 6%.

[0065] S3, uniformly mixing the plate particles, the mixed material, the binder and the lubricant to obtain a premix.

[0066] The mass percentages of the components in the premix are: plate particles 49%, mixed material 32%, binder 16%, and lubricant 3%.

[0067] The binder is starch adhesive and the lubricant is calcium stearate.

[0068] S4, adding the premix into a molding machine for molding to obtain a slab.

[0069] The heating temperature in the molding machine is 190°C and the holding time is 8 minutes.

[0070] S5. The slab is allowed to stand, cooled and dried to obtain a secondary plate.

[0071] The slab is left to stand at room temperature for no less than 2 hours.

[0072] S6. Cut the secondary board material and use the cut secondary board material as packaging material.

[0073] The performance of the secondary plates prepared in Examples 1-3 was tested, and the results are shown in Table 1.

[0074] Table 1 Performance data of secondary plates prepared in Examples 1-3

[0075] It can be seen from Table 1 that the secondary board produced by the preparation method of the present invention has relatively high compressive strength and toughness, and relatively low density, which can meet the requirements of board packaging materials. It also has high degradability, good environmental friendliness and low cost.

[0076] Therefore, the method for preparing packaging materials by recycling waste artificial boards according to the present invention can solve the existing problems of high waste board processing costs, low packaging board strength, and difficulty in degradation.

[0077] 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 method for recycling waste artificial board materials to prepare packaging materials, characterized in that: The following steps are involved: S1, crushing and screening the waste artificial board to obtain board particles; S2, mixing the resin particles with the foaming agent to obtain a mixture; S3, mixing the plate particles, the mixture, the binder and the lubricant uniformly to obtain a premix; S4, adding the premix into a molding machine for molding to obtain a slab; S5, standing, cooling and drying the slab to obtain a secondary plate; S6. Cut the secondary board material and use the cut secondary board material as packaging material.

2. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S1, the thickness of the waste artificial board is 6mm-35mm, and the waste artificial board includes medium-density fiberboard, high-density fiberboard, particleboard, and solid wood sandwich panel. The crushing methods include mechanical crushing and thermal treatment crushing.

3. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S1, the particle size of the plate particles is 1 mm-2 mm.

4. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S2, the resin particles are one of polystyrene particles, polyurethane particles, polyvinyl chloride particles, and polylactic acid foamed particles; the foaming agent is an azo foaming agent; and the mass percentage of the foaming agent in the mixture is 4%-6%.

5. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S3, the mass percentages of the components in the premix are: 45%-55% of plate particles, 30%-35% of mixed material, 15%-20% of binder, and 3%-5% of lubricant.

6. The method for preparing packaging materials by recycling waste artificial boards according to claim 5, characterized in that: In S3, the binder is starch adhesive, urea-formaldehyde adhesive or white latex, and the lubricant is calcium stearate.

7. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S4, the heating temperature in the molding machine is 100° C.-200° C., and the insulation time is 5 min-10 min.

8. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In S5, the slab is left standing at room temperature for not less than 2 hours.

9. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: In the above S6, when the secondary board is cut and used as a packaging material for finished furniture boards, a protective layer is provided between the cut surface of the secondary board and the finished furniture board.

10. The method for preparing packaging materials by recycling waste artificial boards according to claim 1, characterized in that: Before S2, the process also includes soaking the sheet material particles in a flame retardant liquid for 1 to 2 hours; after the soaking, the sheet material particles are dried until the moisture content of the sheet material particles is below 5%.

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