Preparation method and application of modified foamed polyurethane

Abstract

The invention relates to the field of polyurethane, in particular to a preparation method and application of modified foamed polyurethane, and the preparation method comprises the following steps: S1, adding polyether polyol, calcium carbonate, hybrid silicon, a foaming agent, simethicone and a catalyst into a mixing device, and uniformly mixing; s2, after uniform mixing in the step S1, adding polyisocyanate into the mixing device, and continuously stirring and mixing; s3, after the raw materials are stirred to be milky white, rapidly discharging the uniformly mixed raw materials through a mixing device; s3, adding the uniformly mixed raw materials into a mold, and foaming; s4, after maintenance and curing, the modified foaming polyurethane material is obtained. The mixed raw materials can be rapidly discharged through the mixing device, and then the foaming forming effect is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polyurethane, in particular to a preparation method of modified foamed polyurethane and application thereof. BACKGROUND

[0002] Polyurethane material is the best thermal insulation material in the world at present, which is polymerized from isocyanate and hydroxyl compound. Due to containing extremely strong carbamate group, it is insoluble in non-polar groups, has good oil resistance, toughness, wear resistance, aging resistance and adhesion. Foamed polyurethane is a good raw material, which is a foamed product prepared from polyether polyol and isocyanate under the action of foaming agent, has excellent thermal insulation performance, mechanical property, electrical property, acoustic property and chemical resistance, and is widely used in refrigerator, freezer, building energy saving, sofa, mattress, shoe material, high-grade furniture and other fields.

[0003] In order to enhance the performance of foamed polyurethane material, the foamed polyurethane is generally modified to obtain a material with outstanding performance. During preparation and production, the raw materials are mixed and then quickly transferred to a mold to ensure the foaming molding effect. However, the existing method cannot quickly discharge the mixed raw materials from the mixing device, affecting the foaming molding effect. SUMMARY

[0004] The purpose of the present application is to provide a preparation method of modified foamed polyurethane and application thereof, which can quickly discharge the mixed raw materials from the mixing device, thereby ensuring the foaming molding effect.

[0005] The purpose of the present application is achieved by the following technical solutions.

[0006] A preparation method of modified foamed polyurethane, comprising the following steps:

[0007] S1, polyether polyol, calcium carbonate, hybrid silicon, foaming agent, dimethyl silicone oil and catalyst are added into a mixing device and uniformly mixed;

[0008] S2, after uniform mixing in step S1, polyisocyanate is added into the mixing device and continuously stirred and mixed;

[0009] S3, after the raw materials are stirred to be milky white, the uniformly mixed raw materials are quickly discharged through the mixing device;

[0010] S4, the uniformly mixed raw materials are added into a mold for foaming;

[0011] S5, after curing and solidification, a modified foamed polyurethane material is obtained.

[0012] The foaming temperature is 15-25℃, and the time is 20-30min.

[0013] The temperature of the curing is 10-35℃, and the time is 15-35h.

[0014] The temperature of the curing is 10-35℃, and the time is 15-35h.

[0015] The preparation method of the hybrid silicon is: soaking the waste foam in a sodium silicate solution, and then sequentially performing drying, crushing and calcination to obtain the hybrid silicon.

[0016] The waste foam is soaked in a sodium silicate solution after being cleaned.

[0017] The polyisocyanate is diphenylmethane diisocyanate or toluene diisocyanate.

[0018] The foaming agent includes water, azodicarbonamide and dichloromethane.

[0019] The mixing device includes a mixing cylinder arranged transversely, an adding hole arranged at the upper end of the mixing cylinder, a sliding side plate slidingly connected to one end inside the mixing cylinder, a center pipe rotating at the center of the sliding side plate at one end, a blocking side plate rotatingly connected to the other end of the center pipe, the blocking side plate being capable of blocking the other end of the mixing cylinder, and a plurality of stirring frames arranged on the center pipe, after mixing and stirring are completed, the blocking side plate is pulled to make the sliding side plate slide from one end to the other end inside the mixing cylinder, and the raw materials are quickly pushed out.

[0020] The modified foamed polyurethane material prepared by the preparation method of the modified foamed polyurethane is applied to external wall thermal insulation materials. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a flowchart of the preparation method of the modified foamed polyurethane of embodiment one;

[0022] Figure 2 is a flowchart of the preparation method of the modified foamed polyurethane of embodiment two;

[0023] Figure 3 is a flowchart of the preparation method of the modified foamed polyurethane of embodiment three;

[0024] Figures 4 to 6 is a structural schematic diagram of the mixing device;

[0025] Figure 7 and Figure 8 is a structural schematic diagram of the mixing cylinder;

[0026] Figure 8 is a structural schematic diagram of the side plate;

[0027] Figure 9 is a structural schematic diagram of the sleeve pipe;

[0028] Figure 10 This is a schematic diagram of the connection between the central tube and the screw frame;

[0029] Figure 11 This is a schematic diagram of the sliding side plate;

[0030] Figure 12 This is a structural schematic diagram of the side panel.

[0031] In the picture:

[0032] Mixing cylinder 101; Addition hole 102; Threaded pipe 103; Guide plate 104; Limiting plate 105;

[0033] Sleeve 201; Addition tube 202; Worm gear 203;

[0034] Sliding side plate 301; blocking side plate 302; screw 303; central tube 304; stirring rack 305;

[0035] Screw carrier 401; central shaft 402. Detailed Implementation

[0036] like Figure 1 Example 1 illustrates the preparation method of modified polyurethane foam:

[0037] A method for preparing modified polyurethane foam includes the following steps:

[0038] S1. Add polyether polyol, calcium carbonate, hybrid silicon, foaming agent, dimethyl silicone oil and catalyst into the mixing device and mix evenly;

[0039] S2. After step S1 is mixed evenly, add polyisocyanate into the mixing device and continue stirring and mixing.

[0040] S3. After the raw materials are stirred until they turn milky white, the mixed raw materials are quickly discharged through the mixing device;

[0041] S4. Add the mixed raw materials into the mold and allow them to foam.

[0042] S5. After curing and hardening, the modified polyurethane foam material is obtained.

[0043] The foaming temperature is 15℃ and the time is 30 minutes.

[0044] The curing temperature is 50℃ and the time is 18 hours.

[0045] The curing temperature is 10℃ and the time is 35h.

[0046] The method for preparing the hybrid silicon is as follows: waste foam is soaked in sodium silicate solution, and then dried, crushed and calcined in sequence to obtain hybrid silicon.

[0047] The waste foam is cleaned and then soaked in a sodium silicate solution.

[0048] The polyisocyanate is diphenylmethane diisocyanate.

[0049] The foaming agent includes water, azodicarbonamide, and dichloromethane.

[0050] like Figure 2 Example 2 illustrates the preparation method of modified polyurethane foam:

[0051] A method for preparing modified polyurethane foam includes the following steps:

[0052] S1. Add polyether polyol, calcium carbonate, hybrid silicon, foaming agent, dimethyl silicone oil and catalyst into the mixing device and mix evenly;

[0053] S2. After step S1 is mixed evenly, add polyisocyanate into the mixing device and continue stirring and mixing.

[0054] S3. After the raw materials are stirred until they turn milky white, the mixed raw materials are quickly discharged through the mixing device;

[0055] S4. Add the mixed raw materials into the mold and allow them to foam.

[0056] S5. After curing and hardening, the modified polyurethane foam material is obtained.

[0057] The foaming temperature is 20℃ and the time is 25 minutes.

[0058] The curing temperature is 60℃ and the time is 16 hours.

[0059] The curing temperature is 25°C and the curing time is 25 hours.

[0060] The method for preparing the hybrid silicon is as follows: waste foam is soaked in sodium silicate solution, and then dried, crushed and calcined in sequence to obtain hybrid silicon.

[0061] The waste foam is cleaned and then soaked in a sodium silicate solution.

[0062] The polyisocyanate is toluene diisocyanate.

[0063] The foaming agent includes water, azodicarbonamide, and dichloromethane.

[0064] like Figure 3 Example 3 illustrates the preparation method of modified polyurethane foam:

[0065] A method for preparing modified polyurethane foam includes the following steps:

[0066] S1. Add polyether polyol, calcium carbonate, hybrid silicon, foaming agent, dimethyl silicone oil and catalyst into the mixing device and mix evenly;

[0067] S2. After step S1 is mixed evenly, add polyisocyanate into the mixing device and continue stirring and mixing.

[0068] S3. After the raw materials are stirred until they turn milky white, the mixed raw materials are quickly discharged through the mixing device;

[0069] S4. Add the mixed raw materials into the mold and allow them to foam.

[0070] S5. After curing and hardening, the modified polyurethane foam material is obtained.

[0071] The foaming temperature is 25°C and the time is 20 minutes.

[0072] The curing temperature is 65℃ and the time is 15 hours.

[0073] The curing temperature is 35℃ and the time is 15h.

[0074] The method for preparing the hybrid silicon is as follows: waste foam is soaked in sodium silicate solution, and then dried, crushed and calcined in sequence to obtain hybrid silicon.

[0075] The waste foam is cleaned and then soaked in a sodium silicate solution.

[0076] The polyisocyanate is diphenylmethane diisocyanate.

[0077] The foaming agent includes water, azodicarbonamide, and dichloromethane.

[0078] The sodium silicate solution preferably has a mass concentration of 10%-15%; the soaking time is preferably 20-24 hours; the drying includes sequential forced-air drying and vacuum drying. The forced-air drying temperature is 90℃; the time is 1 hour; the forced-air drying is preferably carried out in an electrically heated forced-air drying oven. The vacuum drying temperature is 100℃; the time is 1 hour; the pressure is 0.2-0.4 MPa; the vacuum drying is preferably carried out in a vacuum drying oven. The particle size of the powder obtained after crushing is 70-80 mesh. The calcination is carried out in a tube furnace; the heating rate of the tube furnace is 5℃ / min. The calcination temperature is 900℃; the calcination time is 12 hours.

[0079] like Figures 4-12 The mixing device is described in detail below:

[0080] The mixing device includes a mixing cylinder 101, an adding hole 102, a sliding side plate 301, a blocking side plate 302, a central tube 304, and a stirring rack 305;

[0081] The mixing cylinder 101 is arranged horizontally, and the adding hole 102 is located at the upper end of the mixing cylinder 101. The sliding side plate 301 is slidably connected inside the mixing cylinder 101. One end of the central tube 304 rotates at the center of the sliding side plate 301. The blocking side plate 302 is slidably connected to the other end of the central tube 304, and the blocking side plate 302 can block the other end of the mixing cylinder 101. Multiple stirring racks 305 are evenly arranged on the central tube 304. After the mixing is completed, the blocking side plate 302 is pulled, so that the sliding side plate 301 slides from one end to the other end inside the mixing cylinder 101, and the raw materials are quickly pushed out.

[0082] During mixing, the blocking side plate 302 is first attached to one end of the mixing cylinder 101 and sealed. At this time, the sliding side plate 301 is located at the other end inside the mixing cylinder 101, thereby forming a mixing chamber inside the mixing cylinder 101. Then, the raw material is added into the mixing chamber through the addition hole 102. The first motor installed on the outside of the sliding side plate 301 drives the central tube 304, causing the central tube 304 to drive multiple stirring racks 305 to rotate, thereby mixing and stirring the raw material. After the raw material is mixed evenly, the blocking side plate 302 is pulled to separate from the mixing cylinder 101, thereby opening the port of the mixing cylinder 101 at that end. At the same time, the blocking side plate 302 drives the sliding side plate 301 to slide inside the mixing cylinder 101 through the central tube 304, thereby pushing the raw material towards the open port, thereby quickly discharging the raw material and avoiding affecting the foaming and molding of the raw material in the mold.

[0083] The mixing rack 305 is gate-shaped, and the end of the mixing rack 305 away from the central tube 304 slides against the inner wall of the mixing cylinder 101, so as to better mix the raw materials and avoid the raw materials from remaining on the inner wall of the mixing cylinder 101.

[0084] like Figures 4-12 As shown:

[0085] The mixing device also includes a threaded tube 103, a guide plate 104, a limiting plate 105, and a screw 303. The guide plate 104 is fixed on the lower side of the mixing cylinder 101 near the end of the blocking side plate 302, and the limiting plate 105 is fixed on the upper side of the mixing cylinder 101 near the end of the blocking side plate 302. Threaded tubes 103 are rotatably connected to both sides of the mixing cylinder 101, and screws 303 are threadedly connected to both threaded tubes 103. The two screws 303 are fixed on the blocking side plate 302.

[0086] A second motor is installed at the lower end of the mixing cylinder 101. The second motor simultaneously drives two threaded pipes 103, enabling the two threaded pipes 103 to simultaneously drive two screws 303 to move axially, thereby driving the side plate 302 to move and control the opening or closing of the mixing chamber. At the same time, the sliding side plate 301 is limited by the limiting plate 105 to prevent the sliding side plate 301 from slipping out of the mixing cylinder 101. The limiting plate 105 is equipped with a transmission wheel to support the transmission belt of the second motor driving the two threaded pipes 103, preventing spatial interference between the transmission belt and the rotating central pipe 304 on the sliding side plate 301. The guide plate 104 can be set to centrally guide the discharged raw materials, making it easier for the raw materials to fall into the mold.

[0087] like Figures 4-12 As shown:

[0088] The mixing device further includes a sleeve 201, an adding tube 202, and a worm gear 203. The sleeve 201 is rotatably connected to the mixing cylinder 101, the adding tube 202 is fixed to the sleeve 201, and the worm gear 203 rotates on the guide plate 104 and is meshed with the sleeve 201 for transmission.

[0089] When the addition tube 202 is connected to the addition hole 102, the raw material can be added into the mixing chamber through the addition tube 202. The addition tube 202 makes it easier to add the raw material. When it is necessary to block the addition hole 102, the worm gear 203 is rotated to engage the worm wheel on the transmission sleeve 201, so that the sleeve 201 rotates in the mixing cylinder 101, which in turn drives the addition tube 202 to move, thereby blocking the addition hole 102 through the tube body of the sleeve 201.

[0090] like Figures 4-12 As shown:

[0091] The mixing device also includes a screw frame 401 and a central shaft 402. Multiple screw frames 401 rotate within each stirring frame 305. Each screw frame 401 passes through a central tube 304 and meshes with a central shaft 402 located at the center of the central tube 304. One end of the central shaft 402 is rotatably connected to a side plate 302 and fixed to the output shaft of a third motor mounted on the side plate 302.

[0092] During stirring, the rotating central tube 304 will drive multiple screw carriers 401 to rotate around the axis of the central tube 304. Through the automatic braking function on the third motor, the central shaft 402 remains stationary relative to the side plate 302, thereby forming a transmission between the central shaft 402 and the multiple screw carriers 401, which in turn enables the multiple screw carriers 401 to rotate around their own axes, thereby further improving the stirring efficiency.

[0093] When discharging raw materials, the rotation of the central tube 304 is stopped to prevent the rotating stirring rack 305 from throwing the raw materials away. At this time, the third motor drives the central shaft 402 to rotate, which in turn causes multiple spiral racks 401 to rotate. The rotating spiral racks 401 can spirally push the raw materials away from the central tube 304, so that no matter where the spiral racks 401 are located, the speed at which the raw materials fall can be increased, further increasing the speed of raw material discharge.

[0094] The modified polyurethane foam material prepared by the aforementioned method is used in exterior wall insulation materials.

Claims

1. A method for preparing modified polyurethane foam, characterized in that: Includes the following steps: S1. Add polyether polyol, calcium carbonate, hybrid silicon, foaming agent, dimethyl silicone oil and catalyst into the mixing device and mix evenly; S2. After step S1 is mixed evenly, add polyisocyanate into the mixing device and continue stirring and mixing. S3. After the raw materials are stirred until they turn milky white, the mixed raw materials are quickly discharged through the mixing device; S4. Add the mixed raw materials into the mold and allow them to foam. S5. After curing and hardening, the modified polyurethane foam material is obtained.

2. The method for preparing modified polyurethane foam according to claim 1, characterized in that: The foaming temperature is 15-25℃ and the time is 20-30 minutes.

3. The method for preparing modified polyurethane foam according to claim 1, characterized in that: The curing temperature is 50-65℃, and the time is 15-18 hours.

4. The method for preparing modified foamed polyurethane according to claim 1, characterized in that: The curing temperature is 10-35℃ and the time is 15-35h.

5. The method for preparing modified foamed polyurethane according to claim 1, characterized in that: The method for preparing the hybrid silicon is as follows: waste foam is soaked in sodium silicate solution, and then dried, crushed and calcined in sequence to obtain hybrid silicon.

6. The method for preparing modified foamed polyurethane according to claim 5, characterized in that: The waste foam is cleaned and then soaked in a sodium silicate solution.

7. The method for preparing modified foamed polyurethane according to claim 1, characterized in that: The polyisocyanate is diphenylmethane diisocyanate or toluene diisocyanate.

8. The method for preparing modified polyurethane foam according to claim 1, characterized in that: The foaming agent includes water, azodicarbonamide, and dichloromethane.

9. The method for preparing modified foamed polyurethane according to claim 1, characterized in that: The mixing device includes a horizontally arranged mixing cylinder (101), an addition hole (102) at the upper end of the mixing cylinder (101), a sliding side plate (301) slidably connected to one end of the mixing cylinder (101), a central tube (304) rotatably centered on the sliding side plate (301), a blocking side plate (302) rotatably connected to the other end of the central tube (304), and the blocking side plate (302) can block the other end of the mixing cylinder (101), and multiple stirring racks (305) arranged on the central tube (304). After the mixing is completed, the blocking side plate (302) is pulled, so that the sliding side plate (301) slides from one end to the other end inside the mixing cylinder (101) to quickly push out the raw materials.

10. The modified polyurethane foam material prepared by the method of any one of claims 1-9 is applied to exterior wall insulation materials.

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