Processing equipment for epoxy resin reinforced wood-plastic material

Abstract

The invention discloses processing equipment for an epoxy resin reinforced wood-plastic material. The processing equipment comprises a yarn supply system, a pre-curing system, an extruder, a co-extrusion mold, an online embossing system, a cooling system and a cutting system. The co-extrusion die comprises an interface, a die body, a transition plate, a support plate, a confluence plate, a mouth die, a first co-extrusion plate, a second co-extrusion plate and a third co-extrusion plate, wherein the confluence plate is provided with a pre-cured resin joint; the first co-extrusion plate is provided with a first co-extrusion machine joint and is connected with the first co-extrusion machine; and the second co-extrusion plate is provided with a second co-extrusion machine joint and is connected with the second co-extrusion machine. According to the invention, the degradable epoxy resin and the reinforced fiber are pre-cured in a pre-curing system, so that the surface layer of the degradable epoxy resin still has part of epoxy groups with relatively high activity, and the part of epoxy groups in a co-extrusion mold can be subjected to ring-opening reaction with hydroxyl, anhydride groups and the like in a wood-plastic granulation material to produce covalent bonds; therefore, the interface bonding force between the degradable epoxy resin and the wood plastic is enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of composite material manufacturing and relates to processing equipment for epoxy resin reinforced wood-plastic material. Background Art

[0002] Wood-plastic composite materials are a kind of recyclable green and environmentally friendly new materials made from waste thermoplastics, biomass fibers and various processing aids through extrusion, injection molding, hot pressing, 3D printing and other processes. They are widely used in garden landscapes such as outdoor decking, pavilions, pergolas, fences, wall panels, etc. However, due to the low strength of the main raw material polyolefin, the wood-plastic composite materials on the market generally lack strength and are difficult to use in engineering fields with high requirements for product performance, thus limiting the high-end application of wood-plastic composite materials.

[0003] In order to solve the problem of insufficient mechanical properties of wood plastic products, academia and industry have conducted a lot of exploration, which can be divided into the following aspects: (1) Using various engineering plastics such as PA, PET, ABS, etc. to replace polyolefins. Engineering plastics themselves have excellent performance, but their melting point and processing temperature are often high, while biomass fibers have poor thermal stability. Even if the melting point is lowered by plastic modification, the actual processing difficulty is still relatively large. For example, the melt viscosity is greatly increased, making it difficult to extrude stably; (2) Adding various reinforcing fibers such as glass fiber and carbon fiber to polyolefins or wood plastics, but due to the strong shearing effect of the extruder screw, the viscosity will increase. Strong fibers are sheared and become fibers with a relatively small length-diameter ratio, and the interface bonding between the fibers and the wood-plastic matrix is ​​poor, resulting in limited actual reinforcement effect; (3) Biomass fibers, such as hemp fibers and bamboo fibers, are modified by physical and chemical methods to improve the interface bonding force, but due to the limitations of fiber strength and the strong shearing effect of the extrusion screw, it is difficult to achieve a reinforcement effect in practice; (4) By using wood strips, aluminum alloys and other materials as core materials and co-extruding wood-plastic, the strength of the resulting product is greatly improved, but the cost and energy consumption of aluminum alloys are high, and wood strips are very absorbent. They are prone to absorbing water, swelling and cracking when used outdoors, so actual industrialization faces great difficulties.

[0004] Thermosetting resins such as epoxy resins are added with glass fiber, carbon fiber and other reinforcing fibers to prepare high-strength composite materials. They can be used as structural materials to partially replace metal materials. The products are widely used. They are used as reinforcing materials and co-extruded with wood plastics to meet the requirements in terms of cost and performance. However, since thermosetting resins are non-degradable, they are difficult to recycle and reprocess, and waste pollutes the environment. Therefore, the consensus in the wood plastic industry is that if thermosetting resins are used to reinforce wood plastics, they will become non-recyclable composite materials, which runs counter to green and environmentally friendly wood plastic products. Therefore, what process, equipment and how to prepare wood plastic composite materials with moderate cost, green and renewable, and high performance have become difficult problems in the wood plastic industry. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a processing device for epoxy resin reinforced wood-plastic material which overcomes the defects of the prior art materials and has better performance. The technical scheme adopted by the present invention is: a processing equipment for epoxy resin reinforced wood-plastic material, comprising: a yarn supply system for conveying reinforcing fibers; a resin tank connected to the yarn supply system for immersing the reinforcing fibers in resin; a precuring system connected to the resin tank for receiving the reinforcing fibers impregnated with resin and obtaining precured resin; an extruder having a screw and a heating module therein; a co-extrusion die connected to the extruder for receiving precured resin and elastic layer materials from a first co-extruder and surface materials from a second co-extruder, and forming the wood-plastic profile; wherein the co-extrusion die comprises an interface, a die body, a transition plate, a bracket plate, a busbar, a mouth die, a first co-extrusion plate, a second co-extrusion plate, and a third co-extrusion plate; a precuring resin connection is provided on the upper surface of the busbar for the precuring resin to enter the co-extrusion die; a first co-extrusion machine connection is provided on the side of the first co-extrusion plate, which is connected to the first co-extruder; a second co-extrusion machine connection is provided on the side of the second co-extrusion plate, which is connected to the second co-extruder; the first co-extruder and the second co-extruder are respectively located on both sides of the co-extrusion die.

[0006] As a further improvement of the above method, one end of the resin tank is provided with an introduction roller to ensure that the fibers can be smoothly immersed in the resin, and also provided with a fiber pressing device, wherein the fiber pressing device includes an adjustable pressing mechanism, so that the reinforcing fibers delivered by the yarn supply system can be pressed so that they are completely immersed in the resin contained in the resin tank without causing resin overflow.

[0007] As a further improvement of the above method, the precuring system has a precuring cavity and an infrared temperature control element and a pressure control element connected to the precuring cavity. The precuring cavity has an inlet end and an outlet end. The inlet end is opposite to the resin tank, and the outlet end outputs the precuring resin.

[0008] As a further improvement of the above method, the yarn supply system is composed of a column, a yarn drum, a yarn guide plate, and a slot. The column has a plurality of slots, and the slots are composed of two movable blocks and screws. The movable blocks are fixed to the column by screws, and the yarn drum and the yarn guide plate are connected to the column through the slots. The reinforcing fiber is wound on the yarn drum. The yarn guide plate includes a yarn guide hole and / or a cloth guide hole, and the yarn guide hole is composed of one or more circular holes.

[0009] As a further improvement of the above method, the processing equipment also includes an online embossing system connected to the coextrusion die. The online embossing system includes a film roller, a plain roller and an embossing roller. The film is wound on the film roller, and the film is transported to the plain roller and the embossing roller to coat and emboss the wood-plastic profile. The surface of the plain roller is smooth, and the surface of the embossing roller is engraved with patterns.

[0010] As a further improvement of the above method, the pre-curing system is one or more combinations of microwave drying, ultraviolet curing, and infrared drying.

[0011] As a further improvement of the above method, the processing equipment also includes a cooling system and a cutting system, which are sequentially arranged after the online embossing system and are used for cooling and cutting to obtain the epoxy resin reinforced wood-plastic material and its products.

[0012] Preferably, one or more ultrasonic vibrators are installed on the surface of the coextrusion die.

[0013] The beneficial effects of the present invention are:

[0014] 1. The degradable epoxy resin and reinforcing fiber are pre-cured in the pre-curing system, so that the surface of the degradable epoxy resin still has some highly active epoxy groups. In the co-extrusion mold, these epoxy groups can undergo a ring-opening reaction with the hydroxyl groups and anhydride groups in the wood plastic pellets to produce covalent bonds, thereby enhancing the interfacial bonding force between the degradable epoxy resin and the wood plastic.

[0015] 2. The wood-plastic composite materials on the market contain a high amount of biomass fiber filling, which has good rigidity, but poor toughness and elasticity. The present invention uses a co-extruder to add elastic layer materials into the co-extrusion die, thereby maintaining the overall rigidity of the material while improving the elasticity and toughness of the surface layer of the composite material, thereby expanding its application range.

[0016] 3. The unique design of the co-extrusion mold can ensure that the four materials enter the mold from four different parts, and under the conditions of high temperature and high pressure in the mold, corresponding chemical reactions occur at the interface, which improves the bonding strength of each interface, and finally produces a four-layer wood-plastic composite material including a surface layer, an elastic layer, a base layer and a core layer.

[0017] 4. The flow channel length of the co-extrusion die is limited. If only relying on heat and pressure, the interface reaction is not sufficient. Therefore, multiple ultrasonic vibrators are installed on the surface of the co-extrusion die to provide additional energy on the one hand and increase the contact of the molecules on the interface on the other hand, thereby intensifying the chemical reaction rate and reaction probability, making the interface reaction more sufficient and further improving the bonding strength of each interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a side view of the processing equipment for epoxy resin reinforced wood plastic material in the present invention.

[0019] Figure 2 It is a top view of the processing equipment of epoxy resin reinforced wood plastic material in the present invention

[0020] Figure 3 It is the left side view of the co-extrusion die of the present invention

[0021] Figure 4Coextrusion die right side view

[0022] Figure 5 Top view of coextrusion die

[0023] Figure 6 Front view of yarn supply system

[0024] Figure 7 Side view of yarn supply system

[0025] Figure 8 Schematic diagram of the card slot installation structure in the yarn supply system

[0026] Fig. 9 Schematic diagram of the movable block in the card slot

[0027] Fig.10 Schematic diagram of online embossing system DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the embodiments are briefly described below. Obviously, what is described is only a part of the embodiments of the present invention, not all of them, and those skilled in the art can also obtain other design solutions based on the schematic diagram without paying creative work.

[0029] A processing device for epoxy resin reinforced wood-plastic material, comprising: a yarn supply system for conveying reinforcing fibers; a resin tank connected to the yarn supply system for immersing the reinforcing fibers in resin; a precuring system connected to the resin tank for receiving the reinforcing fibers impregnated with resin and obtaining precured resin; an extruder having a screw and a heating module therein for high-temperature processing of wood-plastic pellets; a co-extrusion die connected to the extruder for receiving precured resin and elastic layer materials from a first co-extruder and surface materials from a second co-extruder, and forming to obtain wood-plastic profiles; wherein the co-extrusion die comprises an interface, a die body, a transition plate, a bracket plate, a manifold, a mouth die, a first co-extrusion plate, a second co-extrusion plate, and a third co-extrusion plate. A precuring resin connection is provided on the upper surface of the manifold for the precuring resin to enter the co-extrusion die; a first co-extrusion machine connection is provided on the side of the first co-extrusion plate for connecting to the first co-extruder; a second co-extrusion machine connection is provided on the side of the second co-extrusion plate for connecting to the second co-extruder. The first co-extruder and the second co-extruder are located on both sides of the co-extrusion die, respectively.

[0030] The beneficial effect of this embodiment is that after the epoxy resin is pre-cured, some epoxy groups are still unreacted, so that the epoxy resin can react chemically with adjacent materials in the co-extrusion mold to improve the interface bonding strength. The co-extrusion mold structure allows the epoxy resin, elastic layer material, surface layer material, and wood-plastic base layer to enter the mold in a certain order, and the high pressure and high temperature of the mold cause chemical reactions at each interface to improve the bonding strength of each interface.

[0031] The elastic layer ensures the overall rigidity of the product while improving the elasticity and toughness of the surface layer, so that people can experience a better foot feel when stepping on the product.

[0032] As a further improvement of the above method, one end of the resin tank is provided with an introduction roller to ensure that the fibers can be smoothly immersed in the resin, and also provided with a fiber pressing device, wherein the fiber pressing device includes an adjustable pressing mechanism, so that the reinforcing fibers delivered by the yarn supply system can be pressed so that they are completely immersed in the resin contained in the resin tank without causing resin overflow.

[0033] As a further improvement of the above method, the precuring system has a precuring cavity and an infrared temperature control element and a pressure control element connected to the precuring cavity, the precuring cavity has an inlet end and an outlet end, the inlet end is opposite to the resin tank, and the outlet end outputs the precured resin. The beneficial effect of the implementation of this scheme is that after the epoxy resin is precured, some epoxy groups are still unreacted, so that the epoxy resin can be chemically reacted with adjacent materials in the co-extrusion mold, thereby improving the interface bonding strength.

[0034] As a further improvement of the above method, the yarn supply system is composed of a column, a yarn drum, a yarn guide plate, and a slot. The column has a plurality of slots, and the slots are composed of two movable blocks and screws. The movable blocks are fixed to the column by screws, and the yarn drum and the yarn guide plate are connected to the column by the slots. The reinforcing fiber is wound on the yarn drum. The yarn guide plate includes a yarn guide hole and / or a cloth guide hole, and the yarn guide hole is composed of one or more circular holes. The beneficial effect of this embodiment is that various forms of reinforcing fibers such as continuous fibers, fiber mats, and fiber cloth can be transported to the next process through the yarn guide plate, thereby solving the problem that different forms of fibers require different equipment. In addition, the design of the slot makes it easier to install and disassemble the reinforcing fiber. At the same time, the slot is modular and universal, and the position and quantity of the yarn drum and the yarn guide plate can be flexibly adjusted to meet the needs of the process.

[0035] As a further improvement of the above method, the processing equipment also includes an online embossing system connected to the co-extrusion die. The online embossing system includes a film roller, a plain roller and an embossing roller. The film is wound on the film roller, and the film is transported to the plain roller and the embossing roller to coat and emboss the wood-plastic profile. The surface of the plain roller is smooth, and the surface of the embossing roller is engraved with patterns. The beneficial effect of this embodiment is that the temperature of the wood-plastic product extruded from the mold is relatively high, and the online embossing system can easily extrude deeper textures on the wood-plastic surface to form realistic wood grain. A layer of transparent wear-resistant plastic film is coated on the surface to increase wear resistance and improve the service life of the product.

[0036] As a further improvement of the above method, the pre-curing system is one or more combinations of microwave drying, ultraviolet curing, and infrared drying. The beneficial effect of this embodiment is that after the epoxy resin is pre-cured, some epoxy groups are still unreacted, thereby ensuring that the epoxy resin reacts chemically with adjacent materials in the co-extrusion mold and improves the interfacial bonding force. If there is no pre-curing, the epoxy resin cannot be completely cured in the co-extrusion mold due to the short co-extrusion mold, which affects the mechanical properties of the product.

[0037] As a further improvement of the above method, the processing equipment also includes a cooling system and a cutting system, which are sequentially arranged after the online embossing system, and are used to cool and cut the epoxy resin reinforced wood-plastic material and its products. The beneficial effect of this embodiment is that the thermal stress in the wood-plastic processing process is quickly released by the cooling system, reducing the defects of the material and the product.

[0038] As a further improvement of the above method, one or more ultrasonic vibrators are installed on the surface of the coextrusion die. The beneficial effect of this embodiment is that the ultrasonic vibrator can intensify the vibration of molecules, increase the contact opportunity of each molecule, accelerate the reaction rate and reaction probability, and thus improve the bonding force of each interface.

Claims

1. A processing equipment for epoxy resin reinforced wood plastic material, characterized in that: include: A yarn supply system (2) for conveying reinforcing fibers (1); a resin tank (3) connected to the yarn supply system (2) for immersing the reinforcing fibers (1) in a resin (4); a precuring system (5) connected to the resin tank (3) for receiving the reinforcing fibers (1) impregnated with the resin (4) and obtaining a precured resin (6); an extruder (7) having a screw and a heating module therein; a coextrusion die (8) connected to the extruder (7) for receiving the precured resin (6) and an elastic layer material from a first coextruder (9) and a surface layer material from a second coextruder (10), and forming the precured resin (6) to obtain a wood-plastic profile (14); wherein the coextrusion die (8) comprises an interface (81 ), a mold body (82), a transition plate (83), a bracket plate (84), a busbar (85), a die (86), a first co-extrusion plate (87), a second co-extrusion plate (88), and a third co-extrusion plate (89); the upper surface of the busbar (85) is provided with a pre-curing resin connection (851) for the pre-curing resin (6) to enter the co-extrusion mold (8); the side of the first co-extrusion plate (87) is provided with a first co-extruder connection (871) connected to the first co-extruder (9); the side of the second co-extrusion plate (88) is provided with a second co-extruder connection (881) connected to the second co-extruder (10); the first co-extruder (9) and the second co-extruder (10) are arranged on both sides of the co-extrusion mold (8).

2. The epoxy resin reinforced wood-plastic material processing equipment according to claim 1, characterized in that: One end of the resin tank (3) is provided with an introduction roller to ensure that the fibers can be smoothly immersed in the resin, and also has a fiber pressing device, wherein the fiber pressing device includes an adjustable pressing mechanism, so that the reinforcing fibers (1) delivered by the yarn supply system (2) can be pressed so that they are completely immersed in the resin (4) contained in the resin tank (3) without causing the resin (4) to overflow.

3. The epoxy resin reinforced wood-plastic material processing equipment according to claim 1, characterized in that: The precuring system (5) comprises a precuring cavity and an infrared temperature control element and a pressure control element connected to the precuring cavity. The precuring cavity comprises an inlet end and an outlet end. The inlet end is opposite to the resin tank (3), and the outlet end outputs the precuring resin (6).

4. The epoxy resin reinforced wood-plastic material processing equipment according to claim 1, characterized in that: The yarn supply system (2) is composed of a column (21), a yarn drum (22), a yarn guide plate (23), and a slot (24); the column (21) has a plurality of slots (24); the slots (24) are composed of two movable blocks (241) and screws (242); the movable blocks (241) are fixed to the column (21) by screws (242); the yarn drum (22) and the yarn guide plate (23) are connected to the column (21) by the slots (24); the reinforcing fibers (1) are wound around the yarn drum (22); the yarn guide plate (23) comprises a yarn guide hole (231) and / or a cloth guide hole (232); the yarn guide hole (231) is composed of one or more circular holes.

5. The processing equipment for epoxy resin reinforced wood-plastic material according to claim 1, characterized in that: The invention also comprises an online embossing system (11) connected to the co-extrusion die (8); the online embossing system (11) comprises a film roller (111), a plain roller (112) and an embossing roller (113); a film (16) is wound around the film roller (111), and the film (16) is transported to the plain roller (112) and the embossing roller (113) to perform film coating and embossing treatment on the wood-plastic profile (14); the surface of the plain roller (112) is smooth, and the surface of the embossing roller (113) is engraved with patterns.

6. The epoxy resin reinforced wood-plastic material processing equipment according to claim 1, characterized in that: The pre-curing system (5) is one or a combination of microwave drying, ultraviolet curing, and infrared drying.

7. The processing equipment for epoxy resin reinforced wood-plastic material according to claim 1, characterized in that: It also comprises a cooling system (12) and a cutting system (13), which are arranged in sequence after the online embossing system (11) and are used for cooling and cutting to obtain epoxy resin reinforced wood-plastic material (15) and products thereof.

8. The epoxy resin reinforced wood plastic material processing equipment according to claim 1, characterized in that: One or more ultrasonic vibrators (17) are installed on the surface of the co-extrusion die (8).

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