Method and device for preparing self-skinning polyurethane steering wheel from polyether polyol

Abstract

The invention discloses a method and device for preparing a self-skinning polyurethane steering wheel from polyether polyol, and relates to the technical field of polyurethane foaming injection molding. The preparation method is technically characterized by comprising the following steps: 1, preparing a component A: sequentially adding polyether polyol 330N, polyether polyol POP36 / 28, a triethylene diamine catalyst with the mass fraction of 33%, foam stabilizer silicone oil, ethylene glycol and deionized water into a reaction kettle, and stirring for 30-60 minutes at normal temperature to prepare the component A; 2, preparing liquefied diphenylmethane diisocyanate as a component B; and 3, preparing the self-skinning polyurethane steering wheel. According to the self-skinning polyurethane steering wheel prepared from the polyether polyol, the self-skinning polyurethane material is prepared from the two-component polyether polyol, so that the self-skinning polyurethane steering wheel is uniform in foam structure, excellent in mechanical property, safe and environmentally friendly; through cooperation of the double polyether polyol, the silicone oil, the ethylene glycol and the liquefied MDI, demolding can be accelerated.

Description

Technical Field

[0001] The invention relates to the technical field of polyurethane foam injection molding, in particular to a method and a device for preparing a self-skinning polyurethane steering wheel by using polyether polyol. Background Art

[0002] Self-skinning polyurethane is also called integral skin polyurethane. It consists of a dense skin and a polyurethane core. Both the skin and the core are made of the same two-component material at one time. The texture of the skin is tight and can form various patterns according to the shape of the mold. It can add beauty while playing a protective role. The polyurethane core reduces the density of the product and gives it elasticity. It has strong wear resistance, waterproofness, deformation resistance, crack resistance, UV resistance and other characteristics. The surface crust strength is good and the appearance is beautiful. Due to the above technical advantages, self-skinning polyurethane is widely used in the manufacturing fields of automobile steering wheels, armrests, headrests, etc.

[0003] The polyether polyols in the prior art are used to prepare the self-skinning polyurethane steering wheels. However, due to the low degree of crosslinking in the system, the polyurethane steering wheels formed after the reaction have problems such as insufficient rigidity and excessive volatile organic compound (VOC) content.

[0004] In addition, during the production process, the prefabricated metal parts need to be placed in the lower mold of the molding mold in advance, and then the upper and lower molds need to be closed. The raw materials are then injected into the mold cavity through the injection molding machine and the nozzle for molding, and the parts are removed after molding. In this process, the placement and positioning of the prefabricated metal parts and the removal of the parts are performed manually or by a robot. Therefore, the staff needs to open the upper mold in turn, and then take out the multiple molded parts formed in the last time in turn, and then put in the prefabricated metal parts for mold closing and injection molding. The operation process is relatively cumbersome and inefficient. In addition, the upper and lower molds are generally fixed by a single-side hinge, which results in limited operating space for the material placement and material removal robots even after the mold is opened, and it is easy to interfere with the upper mold, further affecting production efficiency.

[0005] Therefore, we propose a method and device for preparing a self-skinning polyurethane steering wheel using polyether polyol to solve the above problems. Summary of the invention

[0006] In order to solve the technical problems in the background technology, the present invention provides a method and device for preparing a self-skinning polyurethane steering wheel using polyether polyol.

[0007] To achieve the above object, the present invention provides the following technical solution: a method for preparing a self-skinning polyurethane steering wheel using polyether polyol, comprising the following steps: Step 1: Prepare component A: Accurately weigh the following raw materials in parts by weight: Polyether polyol 330N 5-10 parts; Polyether polyol POP36 / 28 1-5 parts; 0.05-0.2 parts of triethylenediamine catalyst with a mass fraction of 33%; Foam stabilizer silicone oil 0.01-0.1 part; 5-10 parts of ethylene glycol; 0.05-0.2 parts of deionized water; Add them into the reaction kettle in sequence, stir at room temperature for 30 to 60 minutes to obtain component A, which is set aside; Step 2: Prepare component B, which is liquefied diphenylmethane diisocyanate; Step 3: Preparation of a self-skinning polyurethane steering wheel: Place component A and component B in pressure tank A and pressure tank B respectively, and maintain the material temperature in the range of 30-70°C; mix evenly in the mixing area of ​​a pouring machine at a mass ratio of A:B=100:(35-45), foam rapidly, and then quickly inject into an automatic molding mold through the pouring head of the pouring machine for injection reaction molding; demolding is completed 60-90S after pouring to obtain a self-skinning polyurethane steering wheel.

[0008] Preferably, the liquefied diphenylmethane diisocyanate described in step 2 is any one of MDI-100HL, MDI-100LL, and MDI-50H, with a viscosity of ≤60 mPa·s, a freezing point of ≤15°C, and a density of 1.21 to 1.23 g / cm at 25°C. 3 .

[0009] Preferably, the material temperature in step 3 is maintained in the range of 40 to 65°C.

[0010] Preferably, the mass ratio of component A to component B in step three is A:B=100:40.

[0011] A device used in a method for preparing a self-skinning polyurethane steering wheel using polyether polyol, wherein the automatic forming mold described in step three is installed on a base, the self-skinning polyurethane steering wheel is composed of prefabricated metal parts and foaming molding parts, the automatic forming mold includes a lower mold and an upper mold, the top of the upper mold is provided with an injection port, the lower mold is provided with two, the position of the lower mold is moved by a rotating mechanism arranged on the base, and the position of the upper mold is positioned by a positioning mechanism.

[0012] As a further scheme of the present invention: the rotating mechanism includes a rotating groove, which is opened at the top of the base, and the inner wall of the rotating groove is rotatably connected to a rotating disk, and the two lower molds are symmetrically fixedly connected to the top of the rotating disk, and a first motor is installed at the bottom end of the base, and the output end of the first motor is connected to a rotating shaft, one end of the rotating shaft is fixedly connected to the rotating disk, and an arc block is fixedly connected to the bottom end of the inner wall of the rotating groove, and a C-shaped frame is slidably connected to the inside of the lower mold, and the top of the C-shaped frame extends to the inner cavity of the lower mold, and the bottom end of the C-shaped frame extends to the bottom of the rotating disk, and the bottom end of the C-shaped frame is fixedly connected to a vertical rod, and the outer wall of the vertical rod is fixedly connected to a counterweight block.

[0013] As a further scheme of the present invention: the positioning mechanism includes a mounting frame, the mounting frame is fixedly connected to the top of the base, the top of the mounting frame is equipped with a hydraulic cylinder, the upper mold is connected to the output end of the hydraulic cylinder, the top of the mounting frame is symmetrically provided with a movable groove, the inner wall of the movable groove is slidably connected with the movable frame, one side outer wall of the movable frame is fixedly connected with a connecting plate, one side outer wall of the mounting frame is symmetrically fixedly connected with the mounting plate, the outer wall of the mounting plate is symmetrically fixedly connected with the second motor, the output end of the second motor is connected with a threaded rod running through the connecting plate, the bottom end of the mounting frame is located at both sides of the upper mold and is fixedly connected to a reinforcement frame, the bottom end of the reinforcement frame is rotatably connected to a support plate, the top of the support plate is fixedly connected with a connecting shaft, the top of the connecting shaft is fixedly connected with a spur gear, the interior of the mounting frame is located on the outer wall of the spur gear and is slidably connected with a slider extending to the inner cavity of the movable groove, and a spring is connected between the slider and the mounting frame.

[0014] As a further solution of the present invention: the outer wall of the rotating disk is in contact with the inner wall of the rotating groove.

[0015] As a further solution of the present invention: the arc block is in an arc shape, and a first inclined surface is provided at one end of the arc block.

[0016] As a further solution of the present invention: a threaded hole is provided on the outer wall of the connecting plate, and external threads are symmetrically provided on the outer wall of the threaded rod, and the external threads match the threaded hole.

[0017] As a further solution of the present invention: the outer wall of the movable frame is in contact with the inner wall of the movable groove.

[0018] As a further solution of the present invention: a second inclined surface is provided at one end of the slider located in the inner cavity of the movable groove, and the slider is in an L-shape.

[0019] As a further solution of the present invention: a tooth groove is formed on the outer wall of the sliding block, and the tooth groove is meshed with the spur gear.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. The self-skinning polyurethane steering wheel prepared with polyether polyol of the present invention uses a two-component polyether polyol to prepare a self-skinning polyurethane material, has a uniform pore structure, and has excellent mechanical properties; it is safe and environmentally friendly, and can accelerate demoulding through the synergistic combination of di-polyether polyol, silicone oil, ethylene glycol and liquefied MDI.

[0021] 2. The method of preparing a self-skinning polyurethane steering wheel using polyether polyol of the present invention is safe and controllable, has low cost, and can achieve single-furnace production of hundreds of kilograms, which is conducive to industrial mass production applications.

[0022] 3. The present invention is directed to an improved production method and also designs an improved automatic forming mold. The automatic forming mold is provided with a rotating mechanism. The operation of the first motor drives the rotating disk to rotate in the rotating groove. The rotation of the rotating disk drives the two lower molds to shift and exchange positions. During this process, the bottom end of the vertical rod under one lower mold slides along the bottom end of the rotating groove until the vertical rod contacts the arc block, thereby driving the vertical rod to shift. The C-shaped frame shifts to eject the steering wheel from the inner cavity of the lower mold, so that when one lower mold is performing a forming operation, the prefabricated metal parts can be placed in advance into another lower mold, thereby improving the production speed of the steering wheel. At the same time, after the steering wheel in the lower mold is formed, the C-shaped frame automatically ejects the steering wheel from the lower mold, so that the molded steering wheel can be demolded conveniently.

[0023] 4. The automatic forming mold is provided with a positioning mechanism. The second motor drives the threaded rod to rotate, and the rotation of the threaded rod drives the movable frame to slide until the two movable frames fit with the two sides of the upper mold. At this time, the movable frames fit with the two sides of the lower mold at the same time to position the lower mold and the upper mold. After that, the hydraulic cylinder drives the upper mold to move downward and contact with the lower mold to complete the mold closing operation, which is convenient for positioning the positions of the lower mold and the upper mold when the lower mold and the upper mold are closed, to prevent the position deviation of the lower mold and the upper mold from affecting the molding accuracy and effect, and at the same time, prevent the upper mold from moving downward for the mold closing operation before the lower mold and the upper mold are positioned. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of the self-skinning polyurethane steering wheel of the present invention; Figure 2 It is a structural schematic diagram of the upper mold and the lower mold of the automatic forming mold of the present invention; Figure 3 It is a structural schematic diagram of the upper mold of the automatic forming mold of the present invention; Figure 4 It is a structural schematic diagram of the base of the automatic forming mold of the present invention; Figure 5 It is a schematic diagram of the internal structure of the base of the automatic forming mold of the present invention; Figure 6 This is a schematic diagram of the installation of the C-shaped frame of the automatic forming mold of the present invention; Figure 7 It is a structural schematic diagram of the mounting frame of the automatic forming mold of the present invention; Figure 8 It is a schematic diagram of the installation of the reinforcement frame of the automatic forming mold of the present invention; Fig. 9 It is a schematic diagram of the internal structure of the reinforcement frame of the automatic forming mold of the present invention.

[0025] In the figure: 1. prefabricated metal parts; 2. foaming molding parts; 3. lower mold; 4. upper mold; 5. injection port; 6. base; 7. rotating mechanism; 701. rotating groove; 702. rotating disk; 703. rotating shaft; 704. first motor; 705. arc block; 706. C-shaped frame; 707. vertical rod; 708. counterweight block; 8. positioning mechanism; 801. mounting frame; 802. hydraulic cylinder; 803. movable groove; 804. movable frame; 805. connecting plate; 806. mounting plate; 807. second motor; 808. threaded rod; 809. reinforcement frame; 810. support plate; 811. connecting shaft; 812. spur gear; 813. slider; 814. spring. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The following is an explanation of an embodiment of the present invention based on the overall structure of the present invention. Example 1

[0028] See also Figures 1 to 9 In an embodiment of the present invention, a method for preparing a self-skinning polyurethane steering wheel using a polyether polyol comprises the following steps: Step 1: Prepare component A: Accurately weigh the following raw materials in parts by weight: 5 parts of polyether polyol 330N; Polyether polyol POP36 / 28 5 parts; 0.05 parts of triethylenediamine catalyst with a mass fraction of 33%; Foam stabilizer silicone oil 0.01 part; 10 parts of ethylene glycol; 0.05 parts of deionized water; Add them into the reactor in sequence, stir at room temperature for 30 minutes to obtain component A, which is set aside.

[0029] Step 2: Prepare component B, which is liquefied MDI; the liquefied MDI is MDI-100HL, with a viscosity of ≤60mPa·s, a solidification point of ≤15°C, and a density of 1.21-1.23g / cm at 25°C. 3 .

[0030] Step 3: Prepare a self-skinning polyurethane steering wheel: Place component A and component B in pressure tank A and pressure tank B respectively; keep the material temperature at 30°C; according to the mass ratio of A:B=100:45, mix evenly in the mixing zone of the pouring machine and foam quickly, then quickly inject into the automatic molding mold through the pouring head of the pouring machine, and perform injection reaction molding; demolding is completed in 60-90S after pouring, and the self-skinning polyurethane steering wheel is obtained. In this embodiment: a self-skinning polyurethane material is prepared with a two-component polyether polyol, which has good waterproof performance, short surface drying time, uniform pore structure, and rapid demolding. The demolding can be accelerated by the synergistic cooperation of dipolyether polyol, silicone oil, ethylene glycol and liquefied MDI; it has the characteristics of safety and controllability, low cost, and can achieve single-furnace production of 100 kg, which is conducive to industrial mass production.

[0031] like Figure 1 As shown, the integral polyurethane steering wheel is composed of a prefabricated metal part 1 and a foaming molded part 2. In the device for preparing an integral polyurethane steering wheel with polyether polyol described in the present invention, the automatic molding mold described in step 3 is installed on a base 6, and the automatic molding mold includes a lower mold 3 and an upper mold 4. The top of the upper mold 4 is provided with an injection port 5, and the lower mold 3 is provided with two injection ports. The position of the lower mold 3 is moved by a rotating mechanism 7 arranged on the base 6, and the position of the upper mold 4 is positioned by a positioning mechanism 8.

[0032] In this embodiment: when a lower mold 3 is located below an upper mold 4, the parts in the positioning mechanism 8 cooperate to close the lower mold 3 and the upper mold 4. After closing the molds, the pouring head of the pouring machine quickly injects the material into the automatic molding mold through the injection port 5 for injection reaction molding.

[0033] Please refer to Figures 4 to 6 The rotating mechanism 7 includes a rotating groove 701, which is opened at the top of the base 6, and the inner wall of the rotating groove 701 is rotatably connected to a rotating disk 702. The two lower molds 3 are symmetrically fixedly connected to the top of the rotating disk 702. A first motor 704 is installed at the bottom end of the base 6, and the output end of the first motor 704 is connected to a rotating shaft 703, one end of the rotating shaft 703 is fixedly connected to the rotating disk 702, and an arc block 705 is fixedly connected to the bottom end of the inner wall of the rotating groove 701. A C-shaped frame 706 is slidably connected to the inside of the lower mold 3, and the top of the C-shaped frame 706 extends to the inner cavity of the lower mold 3, and the bottom end of the C-shaped frame 706 extends to the bottom of the rotating disk 702. The bottom end of the C-shaped frame 706 is fixedly connected to a vertical rod 707, and the outer wall of the vertical rod 707 is fixedly connected to a counterweight block 708.

[0034] In this embodiment: after the molding is completed, the upper mold 4 and the lower mold 3 are separated, and the first motor 704 is started. The operation of the first motor 704 drives the rotating shaft 703 to rotate. The rotation of the rotating shaft 703 drives the rotating disk 702 to rotate in the rotating groove 701. The rotation of the rotating disk 702 drives the two lower molds 3 to shift and exchange positions. In this process, the bottom end of the vertical rod 707 under one lower mold 3 slides along the bottom end of the rotating groove 701 until the vertical rod 707 contacts the arc block 705 and slides along the top of the arc block 705, thereby driving the vertical rod 707 to shift. The displacement of the vertical rod 707 drives the C-shaped frame 706 to shift. The displacement of the C-shaped frame 706 pushes the steering wheel out of the inner cavity of the lower mold 3, which is convenient for taking out the molded steering wheel. At the same time, the other lower mold 3 moves to the bottom of the upper mold 4, driving the vertical rod 707 Separated from the arc block 705, the vertical rod 707 moves downward under the gravity of the counterweight block 708, contacts and slides with the bottom end of the rotating groove 701; at this time, the C-shaped frame 706 moves out from the inner cavity of the lower mold 3, so that when one lower mold 3 is performing a molding operation, the prefabricated metal component 1 can be placed in advance into another lower mold 3, thereby improving the production speed of the steering wheel. At the same time, when the steering wheel is formed in the lower mold 3, the C-shaped frame 706 automatically ejects the steering wheel from the lower mold 3, thereby facilitating the demoulding operation of the molded steering wheel.

[0035] Please refer to Figures 7 to 9 The positioning mechanism 8 includes a mounting frame 801, the mounting frame 801 is fixedly connected to the top of the base 6, a hydraulic cylinder 802 is installed on the top of the mounting frame 801, the upper mold 4 is connected to the output end of the hydraulic cylinder 802, and a movable groove 803 is symmetrically opened on the top of the mounting frame 801. The inner wall of the movable groove 803 is slidably connected to a movable frame 804, and a connecting plate 805 is fixedly connected to the outer wall of one side of the movable frame 804. A mounting plate 806 is symmetrically fixedly connected to the outer wall of one side of the mounting frame 801, and a second motor 807 is installed on the outer wall of the mounting plate 806. The output end of the machine 807 is connected to a threaded rod 808 that passes through the connecting plate 805. The bottom end of the mounting frame 801 is located on both sides of the upper mold 4 and is fixedly connected to a reinforcement frame 809. The bottom end of the reinforcement frame 809 is rotatably connected to a support plate 810. The top of the support plate 810 is fixedly connected to a connecting shaft 811. The top of the connecting shaft 811 is fixedly connected to a spur gear 812. The interior of the mounting frame 801 is located on the outer wall of the spur gear 812 and is slidably connected to a slider 813 that extends to the inner cavity of the movable groove 803. A spring 814 is connected between the slider 813 and the mounting frame 801.

[0036] In this embodiment: before mold closing, the second motor 807 is started, and the second motor 807 drives the threaded rod 808 to rotate. The rotation of the threaded rod 808 drives the two connecting plates 805 to move closer to each other. The displacement of the connecting plates 805 drives the movable frame 804 to slide in the movable groove 803 until the two movable frames 804 are in contact with the two sides of the upper mold 4. At this time, the movable frame 804 is in contact with the two sides of the lower mold 3 at the same time, and the positions of the lower mold 3 and the upper mold 4 are positioned to prevent the positions of the lower mold 3 and the upper mold 4 from deviating during mold closing, affecting the molding accuracy and effect. After that, the hydraulic cylinder 802 is operated to drive the upper mold 4 to move downward and contact with the lower mold 3 to complete the mold closing operation.

[0037] After the molding operation is completed, the hydraulic cylinder 802 drives the upper mold 4 to reset, and the second motor 807 drives the movable frame 804 to move away from each other, canceling the limit of the lower mold 3 and the upper mold 4. At this time, the slider 813 moves into the movable groove 803 under the elastic force of the spring 814, and the displacement of the slider 813 drives the spur gear 812 to rotate, and the rotation of the spur gear 812 drives the connecting shaft 811 to rotate, and the rotation of the connecting shaft 811 drives the support plate 810 to rotate, and the support plate 810 rotates to the bottom of the upper mold 4 to position the upper mold 4, so as to prevent the upper mold 4 from moving before the lower mold 3 and the upper mold 4 are positioned; when When the movable frame 804 moves and contacts the upper mold 4, the movable frame 804 contacts the slider 813, pushing the slider 813 to move, causing compression on the spring 814, and the displacement of the slider 813 drives the support plate 810 to rotate, and the support plate 810 rotates and separates from the upper mold 4, thereby canceling the fixation of the upper mold 4, and the upper mold 4 can be moved, which is convenient for positioning the positions of the lower mold 3 and the upper mold 4 when the lower mold 3 and the upper mold 4 are closed, preventing the position of the lower mold 3 and the upper mold 4 from deviating and affecting the molding accuracy and effect, and at the same time preventing the upper mold 4 from moving downward for the closing operation before the lower mold 3 and the upper mold 4 are positioned.

[0038] Please refer to Figures 4 to 5 , the outer wall of the rotating disk 702 is in contact with the inner wall of the rotating groove 701 .

[0039] In this embodiment, the first motor 704 drives the rotating shaft 703 to rotate, and the rotating shaft 703 drives the rotating disk 702 to rotate in the rotating groove 701, and the rotating disk 702 drives the two lower molds 3 to shift and exchange positions.

[0040] Please refer to Figures 4 to 6 The arc block 705 is in an arc shape, and a first inclined surface is provided at one end of the arc block 705 .

[0041] In this embodiment: the bottom end of the vertical rod 707 below the lower mold 3 slides along the bottom end of the rotating groove 701 until the vertical rod 707 contacts the first inclined surface at one end of the arc block 705, and slides along the top of the arc block 705, thereby driving the vertical rod 707 to move, and the displacement of the vertical rod 707 drives the C-shaped frame 706 to move, and the displacement of the C-shaped frame 706 pushes the steering wheel out of the inner cavity of the lower mold 3.

[0042] Please refer to Figures 7 to 9 A threaded hole is provided on the outer wall of the connecting plate 805, and external threads are symmetrically provided on the outer wall of the threaded rod 808, and the external threads match the threaded hole.

[0043] In this embodiment, the second motor 807 rotates to drive the threaded rod 808 to rotate, and the rotation of the threaded rod 808 drives the two connecting plates 805 to move closer to each other.

[0044] Please refer to Figures 7 to 9 , the outer wall of the movable frame 804 is in contact with the inner wall of the movable groove 803 .

[0045] In this embodiment, the connection plate 805 is displaced to drive the movable frame 804 to slide in the movable groove 803 until the two movable frames 804 are in contact with the two sides of the upper mold 4 .

[0046] Please refer to Figures 7 to 9 A second inclined surface is provided at one end of the slider 813 located in the inner cavity of the movable groove 803 . The slider 813 is L-shaped. A tooth groove is provided on the outer wall of the slider 813 , and the tooth groove is meshed with the spur gear 812 .

[0047] In this embodiment: the movable frame 804 contacts the slider 813, pushing the slider 813 to move, causing compression on the spring 814, the displacement of the slider 813 drives the spur gear 812 to rotate, the rotation of the spur gear 812 drives the connecting shaft 811 to rotate, and the rotation of the connecting shaft 811 drives the support plate 810 to rotate. Example 2

[0048] A method for preparing a self-skinning polyurethane steering wheel using polyether polyol comprises the following steps: Step 1: Prepare component A: Accurately weigh the following raw materials in parts by weight: 7.5 parts of polyether polyol 330N; 3.5 parts of polyether polyol POP36 / 28; 0.13 parts of triethylenediamine catalyst with a mass fraction of 33%; Foam stabilizer silicone oil 0.06 parts; 8 parts of ethylene glycol; 0.15 parts of deionized water; Add them into the reaction kettle in sequence, stir at room temperature for 45 minutes to obtain component A, which is set aside; Step 2: Prepare component B, which is liquefied MDI; the liquefied MDI is MDI-100LL, with a viscosity of ≤60mPa·s, a solidification point of ≤15°C, and a density of 1.21-1.23g / cm at 25°C. 3 .

[0049] Step 3: Prepare a self-skinning polyurethane steering wheel: place component A and component B in pressure tank A and pressure tank B respectively; maintain the material temperature at 50°C; mix evenly in the mixing area of ​​a casting machine at a mass ratio of A:B=100:40, and then quickly foam, and then quickly inject into the automatic molding mold through the casting head of the casting machine for injection reaction molding; complete demolding 60-90S after the casting is completed to obtain the self-skinning polyurethane steering wheel.

[0050] The application equipment is the same as that in Example 1 and will not be described in detail here. Example 3

[0051] A method for preparing a self-skinning polyurethane steering wheel using polyether polyol comprises the following steps: Step 1: Prepare component A: Accurately weigh the following raw materials in parts by weight: 10 parts of polyether polyol 330N; 1 part of polyether polyol POP36 / 28; 0.2 parts of triethylenediamine catalyst with a mass fraction of 33%; Foam stabilizer silicone oil 0.1 part; 5 parts of ethylene glycol; 0.2 parts of deionized water; Add them into the reaction kettle in sequence, stir at room temperature for 60 minutes to obtain component A, which is set aside; Step 2: Prepare component B, which is liquefied MDI; the liquefied MDI is MDI-50H, with a viscosity of ≤60mPa·s, a freezing point of ≤15°C, and a density of 1.21-1.23g / cm at 25°C. 3 .

[0052] Step 3: Prepare a self-skinning polyurethane steering wheel: place component A and component B in pressure tank A and pressure tank B respectively; maintain the material temperature at 70°C; mix evenly in the mixing area of ​​a casting machine at a mass ratio of A:B=100:35, and then quickly foam, and then quickly inject into the automatic molding mold through the casting head of the casting machine for injection reaction molding; complete demolding 60-90S after the casting is completed to obtain the self-skinning polyurethane steering wheel.

[0053] The application equipment is the same as that in Example 1 and will not be described in detail here.

[0054] Comparative Example 1 A method for preparing a self-skinning polyurethane steering wheel using polyether polyol, the specific implementation method is the same as that of Example 2, the only difference is that the polyether polyol POP36 / 28 is not added.

[0055] Comparative Example 2 A method for preparing a self-skinning polyurethane steering wheel using polyether polyol, the specific implementation method is the same as that of Example 2, the only difference is that ethylene glycol is not added.

[0056] Comparative Example 3 Refer to the preparation method of Example 5 of the invention patent with application publication number CN108047422A, entitled Polyurethane composition for automobile steering wheel and preparation method thereof.

[0057] Performance Test: The self-skinning polyurethane steering wheels prepared in the above Examples 1 to 3 and Comparative Examples 1 to 2 were respectively tested for density, hardness, tensile strength, elongation at break, and tear strength. Each test was performed according to the following standard methods: core density, GB / T6343-2009; hardness, GB / T2411-2008; tensile strength, elongation at break, GB / T6344-2008; tear strength, GB / T10808-2006; VOC NESM0402[2005-1], low odor test PV3900-2000. The measured data of each sample are shown in Table 1 below.

[0058] Table 1 - Performance test results of self-skinning polyurethane steering wheels prepared in various embodiments and comparative examples

[0059] Note: The preparation method and product performance test of Comparative Example 3 refer to Example 5 of CN108047422A.

[0060] From the above test data, it can be seen that under the same experimental conditions, the self-skinning polyurethane steering wheel product prepared by the preparation method of the present invention has excellent mechanical properties such as density, hardness, tensile strength, tear strength, etc., is safe and environmentally friendly, and the preparation method is simple and fast.

[0061] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a self-skinning polyurethane steering wheel using polyether polyol, characterized in that: The following steps are involved: Step 1: Prepare component A: Accurately weigh the following raw materials in parts by weight: Polyether polyol 330N 5-10 parts; Polyether polyol POP36 / 28 1-5 parts; 0.05-0.2 parts of triethylenediamine catalyst with a mass fraction of 33%; Foam stabilizer silicone oil 0.01-0.1 part; 5-10 parts of ethylene glycol; 0.05-0.2 parts of deionized water; Add them into the reaction kettle in sequence, stir at room temperature for 30 to 60 minutes to obtain component A, which is set aside; Step 2: Prepare component B, which is liquefied diphenylmethane diisocyanate; Step 3: Preparation of a self-skinning polyurethane steering wheel: Place component A and component B in pressure tank A and pressure tank B respectively, and maintain the material temperature in the range of 30-70°C; mix evenly in the mixing area of ​​a pouring machine at a mass ratio of A:B=100:(35-45), foam rapidly, and then quickly inject into an automatic molding mold through the pouring head of the pouring machine for injection reaction molding; demolding is completed 60-90S after pouring to obtain a self-skinning polyurethane steering wheel.

2. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 1, characterized in that: The automatic molding mold described in step three is installed on a base (6). The self-skinning polyurethane steering wheel is composed of a prefabricated metal component (1) and a foaming molded component (2). The automatic molding mold includes a lower mold (3) and an upper mold (4). The top of the upper mold (4) is provided with an injection port (5). The lower mold (3) is provided with two ports. The position of the lower mold (3) is moved by a rotating mechanism (7) provided on the base (6), and the position of the upper mold (4) is positioned by a positioning mechanism (8).

3. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 2, characterized in that: The rotating mechanism (7) comprises a rotating groove (701), the rotating groove (701) is opened at the top of the base (6), the inner wall of the rotating groove (701) is rotatably connected to a rotating disk (702), the two lower molds (3) are symmetrically fixedly connected to the top of the rotating disk (702), the bottom end of the base (6) is installed with a first motor (704), the output end of the first motor (704) is connected to a rotating shaft (703), one end of the rotating shaft (703) is connected to the rotating disk ( The bottom end of the inner wall of the rotating groove (701) is fixedly connected to an arc block (705), the interior of the lower mold (3) is slidably connected to a C-shaped frame (706), the top end of the C-shaped frame (706) extends to the inner cavity of the lower mold (3), the bottom end of the C-shaped frame (706) extends to the bottom of the rotating disk (702), the bottom end of the C-shaped frame (706) is fixedly connected to a vertical rod (707), and the outer wall of the vertical rod (707) is fixedly connected to a counterweight block (708).

4. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 3, characterized in that: The positioning mechanism (8) comprises a mounting frame (801), the mounting frame (801) is fixedly connected to the top of the base (6), a hydraulic cylinder (802) is installed on the top of the mounting frame (801), the upper mold (4) is connected to the output end of the hydraulic cylinder (802), the top of the mounting frame (801) is symmetrically provided with movable grooves (803), the inner wall of the movable groove (803) is slidably connected to a movable frame (804), one side outer wall of the movable frame (804) is fixedly connected to a connecting plate (805), one side outer wall of the mounting frame (801) is symmetrically fixedly connected to a mounting plate (806), the outer wall of the mounting plate (806) is installed with a second motor (807), and the second motor The output end of (807) is connected to a threaded rod (808) that passes through the connecting plate (805); the bottom end of the mounting frame (801) is located on both sides of the upper mold (4) and is fixedly connected to a reinforcement frame (809); the bottom end of the reinforcement frame (809) is rotatably connected to a support plate (810); the top end of the support plate (810) is fixedly connected to a connecting shaft (811); the top end of the connecting shaft (811) is fixedly connected to a spur gear (812); the interior of the mounting frame (801) is slidably connected to the outer wall of the spur gear (812) and is extended to the inner cavity of the movable groove (803); a spring (814) is connected between the slider (813) and the mounting frame (801).

5. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 3, characterized in that: The outer wall of the rotating disk (702) fits in contact with the inner wall of the rotating groove (701).

6. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 3, characterized in that: The arc block (705) is in an arc shape, and one end of the arc block (705) is provided with a first inclined surface.

7. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 4, characterized in that: The outer wall of the connecting plate (805) is provided with a threaded hole, and the outer wall of the threaded rod (808) is symmetrically provided with external threads, and the external threads match the threaded hole.

8. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 4, characterized in that: The outer wall of the movable frame (804) fits in with the inner wall of the movable groove (803).

9. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 4, characterized in that: A second inclined surface is provided at one end of the sliding block (813) located in the inner cavity of the movable groove (803), and the shape of the sliding block (813) is L-shaped.

10. The device used in the method for preparing a self-skinning polyurethane steering wheel with polyether polyol according to claim 4, characterized in that: The outer wall of the sliding block (813) is provided with a tooth groove, and the tooth groove is meshed with the spur gear (812).

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