CN109320952B - Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder - Google Patents
Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder Download PDFInfo
- Publication number
- CN109320952B CN109320952B CN201811093164.8A CN201811093164A CN109320952B CN 109320952 B CN109320952 B CN 109320952B CN 201811093164 A CN201811093164 A CN 201811093164A CN 109320952 B CN109320952 B CN 109320952B
- Authority
- CN
- China
- Prior art keywords
- bead foam
- temperature
- extrusion
- low density
- tpu
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/122—Hydrogen, oxygen, CO2, nitrogen or noble gases
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/0066—Use of inorganic compounding ingredients
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/06—CO2, N2 or noble gases
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/18—Binary blends of expanding agents
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/18—Binary blends of expanding agents
- C08J2203/182—Binary blends of expanding agents of physical blowing agents, e.g. acetone and butane
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2205/00—Foams characterised by their properties
- C08J2205/04—Foams characterised by their properties characterised by the foam pores
- C08J2205/052—Closed cells, i.e. more than 50% of the pores are closed
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
- C08J2375/06—Polyurethanes from polyesters
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
- C08J2375/08—Polyurethanes from polyethers
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The invention provides a method for preparing low-density TPU bead foam by coupling and modifying Polytetrafluoroethylene (PTFE) and talcum powder based extrusion foaming, which comprises the following steps of: 85-98 wt% of TPU, 0.5-10 wt% of PTFE, 0.5-8 wt% of talcum powder, 0-10 wt% of supercritical carbon dioxide and 0-1 wt% of supercritical nitrogen. The foaming multiplying power of the foamed product prepared by the method can reach more than 10 times, and the density of the foamed product can be as low as 0.1g/cm3The foamed product has a more exquisite, more uniform, more regular and higher porosity cell structure, and the closed porosity reaches 96 percentThe bead foam has uniform appearance and luster, and is easy to form by steam molding in the later period.
Description
Technical Field
The invention relates to the technical field of microporous plastic preparation, in particular to a method for preparing low-density thermoplastic polyurethane bead foam by extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder.
Background
Thermoplastic Polyurethane (TPU) bead foam is a beaded material with a cellular structure, produced by foaming, based on thermoplastic polyurethane. Through steam molding or bonding molding, TPU bead foam can be processed into a massive foam product with a certain geometric structure, has the characteristics of light weight, high elasticity, heat insulation, noise elimination, toughness and the like, and can be widely applied to the fields of sports equipment, packaging, building, transportation, safety protection and the like. Currently, TPU bead foams are predominantly prepared by the pot pressure foaming process. The kettle pressure foaming method has relatively simple process control, but has low production efficiency, unstable process, poor product uniformity and certain potential safety hazard in the production process. Compared with a kettle pressure foaming method, the extrusion foaming method for preparing TPU bead foam has the obvious advantages of high forming efficiency, high automation degree, high design flexibility, uniform and consistent product structure and the like, and is an important development direction of a future polymer foam bead preparation technology.
Patent document CN 106541508A discloses a method for preparing expanded beads by combining an endothermic blowing agent with supercritical nitrogen. The method mainly comprises the following steps: 1) mixing thermoplastic polyurethane particles with a heat absorption type chemical foaming agent and a nucleating agent, adding the mixture into a charging barrel of a single-screw extruder, heating and plasticizing the mixture into a polymer melt through the extruder, and simultaneously injecting supercritical nitrogen into a fourth area of the extruder to mix the supercritical nitrogen with the polymer melt; 2) the mixture enters a fifth area and a sixth area with a temperature control system to be mixed and cooled to obtain a cooled and uniformly mixed polymer; 3) extruding the mixture from a mouth die of an extruder, and performing underwater circular cutting to obtain the self-skinning thermoplastic polyurethane foaming beads.
Patent document CN 104385479 a discloses a method for preparing TPU expanded beads by continuous extrusion foaming. The method comprises the following steps: 1) mixing TPU particles with organic modified inorganic nano particles, adding the mixed TPU particles into a charging barrel of a first extruder, heating by a screw to melt the TPU particles into a polymer melt, and injecting a supercritical fluid into the tail end of the first extruder to mix the supercritical fluid with the polymer melt; 2) injecting the mixed polymer/high-pressure fluid melt into a second extruder through a melt pump, and gradually reducing the temperature of a heating zone of the second extruder to obtain a cooled and uniformly mixed polymer/supercritical fluid melt; thirdly, extruding the polymer/supercritical fluid melt from a second extruder die, and performing underwater circular cutting to obtain TPU foamed particles.
Patent document CN 103709726B discloses a process for preparing TPU bead foam by extrusion foaming. The method mainly relates to a foaming material formula and a matched foaming method thereof. The material formula mainly comprises 100 parts by weight of thermoplastic polyurethane, 0.01-0.5 part by weight of foaming nucleating agent, 0.01-0.2 part by weight of antioxidant and 1-40 parts by weight of supercritical fluid foaming agent. The foaming method mainly comprises the following steps: firstly, uniformly mixing various materials in the material formula; then, the mixed materials are put into an extruder for granulation to obtain particles suitable for foaming; finally, the particles are put into a special foaming extruder for foaming.
Currently, the extrusion foaming preparation technology of TPU bead foam is not mature, and the main problem is that the prepared TPU bead foam has high density (the density is generally more than 0.2 g/cm)3) The main reasons for the defects of large shrinkage, uneven structure, high opening ratio and the like are poor viscoelasticity and slow crystallization rate of the TPU melt.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a method for preparing low-density Thermoplastic Polyurethane (TPU) bead foam by coupling and modifying Polytetrafluoroethylene (PTFE) and talcum powder and extruding and foaming, and the method can be used for preparing TPU bead foam with low density, uniform cells and high closed cell rate, and has the outstanding advantages of stability, reliability, high production efficiency, low cost and the like.
The invention is realized by the following technical scheme:
firstly, the invention provides a method for preparing low-density Thermoplastic Polyurethane (TPU) bead foam, which is prepared by coupling, modifying and extruding Polytetrafluoroethylene (PTFE) and talcum powder for foaming, wherein the method adopts the following material formula: 85-98 wt% of TPU, 0.5-10 wt% of PTFE, 0.5-8 wt% of talcum powder, 0-10 wt% of supercritical carbon dioxide and 0-1 wt% of supercritical nitrogen.
Preferably, the content of the TPU in the material formula is 85-98 wt%, preferably 90-95 wt%;
preferably, the TPU has a hardness of from 75A to 95A, preferably from 80A to 90A.
The TPU is selected from polyether TPU and polyester TPU.
Preferably, the content of PTFE in the material formula is 1-8 wt%, preferably 2-6 wt%.
Preferably, the content of the talcum powder in the material formula is 1-6 wt%, and preferably 2-5 wt%.
Preferably, the content of the supercritical carbon dioxide in the material formula is 2-9 wt%, and preferably 3-6 wt%.
Preferably, the content of the supercritical nitrogen in the material formula is 0.1-0.6 wt%, and preferably 0.2-0.4 wt%.
Preferably, the method for preparing the low-density thermoplastic polyurethane bead foam by coupling, modifying and extruding and foaming Polytetrafluoroethylene (PTFE) and talcum powder comprises the following steps:
(1) adding TPU, PTFE and talcum powder into a charging barrel of a double-screw extruder of extrusion foaming equipment through a hopper;
(2) after the TPU is melted and is primarily mixed with the PTFE and the talcum powder, sequentially and respectively injecting supercritical carbon dioxide and a certain amount of supercritical nitrogen into a charging barrel through two gas injection ports arranged on the charging barrel of a double-screw extruder;
(3) fully and uniformly mixing TPU, PTFE, talcum powder and supercritical fluid in a double-screw extruder, then extruding, and then sequentially flowing through a static mixer, a gear pump, a melt cooler, an extrusion die and the like arranged at the downstream of the double-screw extruder to extrude and foam;
(4) and cutting, conveying and drying the extruded foaming material by an underwater cutting system to finally obtain the TPU bead foam.
Preferably, the extrusion foaming apparatus comprises: the device comprises an extrusion mixing unit, a supercritical fluid injection unit, a static mixer, a gear pump, a melt cooler, an extrusion port die and an underwater pelletizing system; the extrusion mixing unit, the static mixing unit, the gear pump, the melt cooler, the extrusion port die and the underwater pelletizing system are sequentially connected (connected in series); and the supercritical fluid injection unit is connected with the gas injection hole of the extrusion mixing unit through a pipeline.
Preferably, the main body of the extrusion mixing unit is a double-screw extruder which mainly comprises an extruder motor, double screws, a charging barrel, a charging hopper, a screw temperature controller, a charging barrel temperature controller and a charging barrel heating element; 2 gas injection holes are sequentially formed in a charging barrel of the double-screw extruder; a heating and cooling unit is arranged outside the charging barrel of the double-screw extruder and is connected (in series) with a charging barrel temperature controller; a temperature control pipeline is arranged in a screw of the double-screw extruder and is connected with a screw temperature controller; the diameter of the screw is 27mm, and the length-diameter ratio is 50;
the supercritical fluid injection unit comprises two sets of supercritical fluid injection devices I and II, and each set of supercritical fluid injection device consists of a storage tank, a fluid pressure regulating metering pump and a connecting pipeline;
a shunting module, a mixing module and a converging module are arranged inside the static mixer;
the melt cooler comprises a melt flow micro-pipeline and a temperature control fluid medium flow micro-pipeline inside;
the extrusion die comprises 8 extrusion holes, and the aperture is 2.5 mm; the extrusion die is provided with a pressure monitoring unit;
the underwater pelletizing system consists of a cooling water circulating device, an underwater pelletizing motor, an underwater pelletizing cutter, a drying device and connecting pipelines among the underwater pelletizing cutter and the drying device.
Preferably, the temperature of the mixing section of the cylinder of the double-screw blending extruder (or the temperature of the double screws is regulated) is 170-240 ℃, and preferably 180-220 ℃;
preferably, the temperature of the static mixer is 140-190 ℃, preferably 150-170 ℃;
preferably, the temperature of the gear pump is 140-190 ℃, and preferably 150-170 ℃;
preferably, the control pressure of the gear pump is 8-20 MPa, preferably 10-15 MPa;
preferably, the temperature of the melt cooler is 100-160 ℃, and preferably 120-145 ℃;
preferably, the temperature of the extrusion die is 100-160 ℃, and preferably 120-145 ℃;
preferably, the pressure of the extrusion die is 10-25 MPa, preferably 12-20 MPa;
preferably, the system temperature of the underwater pelletizing device is 10-80 ℃, and preferably 30-60 ℃;
preferably, the system pressure of the underwater pelletizing system is 0.2-0.8 MPa, and preferably 0.3-0.6 MPa.
Compared with the prior art, the invention has the beneficial effects that: the foaming multiplying power of the foaming product can reach more than 10 times, and the density of the foaming product can be as low as 0.1g/cm3And on the left and right, the foamed product has a more exquisite, more uniform, more regular and higher porosity cell structure, the closed porosity reaches more than 96%, the bead foam has uniform appearance and luster, and the bead foam is easy to form by steam molding in the later period.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.
FIG. 1 is a schematic view of the apparatus of the extrusion foaming apparatus used in the present invention.
Wherein, the storage tank I1, the extruder motor 2, the fluid metering pump I3, the loading hopper 4, the charging barrel 5, the twin-screw 6, the fluid metering pump II7, the static mixer 8, the storage tank II9, the gear pump 10, the melt cooler 11, the extrusion die 12, the pressure monitoring unit 13, the cooling water circulating device 14, the pipeline 15, the pipeline 16, the underwater grain cutting tool 17, the drying device 18, the underwater grain cutting motor 19, the pipeline 20, the conduit 21, the polymer foam beads 22, the screw temperature controller 23, the charging barrel temperature controller 24 and the charging barrel heating element 25.
FIG. 2 is the internal cell structure of the TPU bead foam prepared in example 1.
FIG. 3 is the internal cell structure of the TPU bead foam prepared in example 2.
FIG. 4 is the internal cell structure of the TPU bead foam prepared in example 3.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention. The preferred embodiments and materials described herein are intended to be exemplary only.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
As shown in fig. 1, the extrusion foaming apparatus used in the present invention includes: the device comprises an extrusion mixing unit (the main body of the device is a double-screw blending extruder), a supercritical fluid injection unit, a static mixing unit, a gear pump, a melt cooler, an extrusion die and an underwater pelletizing system. The device comprises a double-screw blending extruder (hereinafter also referred to as a double-screw extruder), a static mixer, a gear pump, a melt cooler, an extrusion die and an underwater pelletizing system, wherein the double-screw blending extruder (hereinafter also referred to as a double-screw extruder) is sequentially connected with the static mixer, the gear pump, the melt cooler, the extrusion die and the underwater pelletizing system, and two gas injection holes are formed in a charging barrel of the double-screw extruder and are connected (connected in series).
The extrusion mixing unit, the static mixing unit 8, the gear pump 10, the melt cooler 11, the extrusion die head 12, the underwater pelletizing system and the like are connected in series in sequence, and the supercritical fluid injection unit is connected with a gas injection hole in a charging barrel of the extrusion mixing unit through a pipeline.
The main body of the extrusion mixing unit is a double-screw extruder which mainly comprises an extruder motor 2, a double screw 6, a charging barrel 5, a charging hopper 4, a screw temperature controller 23, a charging barrel temperature controller 24 and a charging barrel heating element 25; 2 gas injection holes are sequentially formed in a charging barrel of the double-screw extruder; a temperature control pipeline is arranged in a screw of the double-screw extruder and is connected with a screw temperature controller, so that the temperature of the screw can be accurately controlled; the heating and cooling unit is arranged outside the charging barrel of the double-screw extruder and is connected with the charging barrel temperature controller, so that the temperature of the charging barrel can be accurately controlled; the diameter of the screw is 27mm, and the length-diameter ratio is 50.
The supercritical fluid injection unit comprises two sets of supercritical fluid injection devices (for convenience of discussion, expressed as I and II), and each set of supercritical fluid injection device consists of a storage tank (storage tank I1 or II 9), a fluid pressure regulating metering pump (metering pump I1 or metering pump II 7) and a connecting pipeline.
The static mixer 8 is internally provided with a flow dividing module, a mixing module and a converging module, and the uniformity of the polymer melt/supercritical fluid mixture is remarkably improved by dividing, cutting, moving and mixing the polymer melt/supercritical fluid mixture.
The melt cooler 11 contains a large number of melt flow microchannels and temperature-controlled fluid medium flow microchannels inside, and cools the polymer melt/supercritical fluid mixture flowing out of the static mixer by introducing a fluid medium of a certain temperature into the temperature-controlled fluid medium flow microchannels.
The extrusion die 12 comprises 8 extrusion holes with the aperture of 2.5 mm; the extrusion die is provided with a pressure monitoring unit 13 which can detect in real time the pressure of the polymer melt/supercritical fluid mixture flowing into it.
The underwater pelletizing system consists of a cooling water circulating device 14, an underwater pelletizing motor 19, an underwater pelletizing cutter 17, a drying device 18 and connecting pipelines (a pipeline 15, a pipeline 16 and a pipeline 20) among the devices.
The processing method of the equipment comprises the following steps: adding TPU, PTFE, talcum powder and other solid granular materials into a double-screw blending extruder from a hopper 4; under the drive of the extruder motor 2, the extruder twin-screw 6 which rotates ceaselessly compresses and shears the polymer solid particles, and conveys the polymer solid particles forwards; in this process, the heat generated by the barrel heating element 25 is transferred to the solid polymer particles via the barrel 5, thereby gradually softening and melting the solid polymer particles; simultaneously, the supercritical fluid in the storage tank I1 and the supercritical fluid in the storage tank II9 are respectively injected into the melt between the charging barrel 5 and the double screw 6 by the fluid metering pump I3 and the fluid metering pump II7, and the two supercritical fluids are fully mixed with the polymer melt under the shearing and stirring actions of the double screws; the temperature of the polymer melt and the supercritical fluid mixture is jointly set by a screw temperature controller 23 and a cylinder temperature controller 24; after the mixture of the polymer melt and the supercritical fluid flows out of the extruder, the mixture enters a static mixer 8 to further enhance the uniformity of the mixture; then, the polymer melt and supercritical fluid mixture flows into the gear pump 10 to set the pressure of the polymer melt and supercritical fluid mixture upstream of the gear pump 10; after the mixture of the polymer melt and the supercritical fluid flows out of the gear pump, the mixture enters a melt cooler 11 to uniformly cool the mixture of the polymer melt and the supercritical fluid, and finally the temperature of the mixture is set at a certain set level; then the mixture of the polymer melt and the supercritical fluid enters an extrusion opening die 12, and at the outlet of the extrusion opening die 12, the polymer melt and the supercritical fluid mixture are subjected to phase separation and foaming due to the sharp reduction of the system pressure; the foaming material extruded from the extrusion die 12 is cut into particles under the cutting action of an underwater granule cutting tool 17 driven by a granule cutting machine motor 19; then, under the transportation of the circulating water provided by the cooling water circulating device 14, the granular substances obtained by cutting by the underwater granule cutting tool 17 are conveyed to the drying device 18 through the pipeline 16; after drying, the pellets are ejected through a conduit 21 to give the final TPU bead foam 22.
The following examples 1-3 all used an extrusion foaming apparatus as described above to prepare low density TPU bead foams.
Example 1
The raw material is polyester TPU, the hardness of which is 80A, and the density of which is 1.20g/cm3(@23 ℃) and the addition amount is 87.7 wt%; the mesh number of the PTFE solid powder is 100 meshes, and the addition amount is 2 wt% (mass fraction); the mesh number of the talcum powder is 3000 meshes, and the addition amount is 4 wt%; the supercritical fluid I is carbon dioxide with the purity of 99.9 percent, and the supercritical fluid II is nitrogen with the purity of 99.5 percent; the injection amount of carbon dioxide was 6.0 wt%, and the injection amount of nitrogen was 0.3 wt%.
The temperature of the double screw is set to be 180 ℃; the temperature of a charging barrel of the double-screw extruder is sequentially set from a hopper to an extrusion port to be 60-160-180-170 ℃, and the rotating speed of a screw is 30 revolutions per minute; the temperature of the static mixer was set to 150 ℃; the control pressure of the gear pump is set to be 12.5MPa, and the temperature of the gear pump is set to be 150 ℃; the temperature of the melt cooler was set to 120 ℃; the temperature of the extrusion die is set to be 120 ℃, and the pressure is set to be 12.5 MPa; the rotating speed of the underwater granulating cutter is set to be 500 revolutions per minute; the temperature of cooling water provided by the underwater pelletizing system is set to be 30 ℃, and the pressure of the cooling water is set to be 0.3 MPa.
By utilizing the extrusion foaming device and the process parameters, the prepared polyurethane bead foam has the foaming multiplying power of 9.0 times and the density of 0.13g/cm3The cells were uniform, the average cell diameter was 105.8 μm, and the closed cell ratio was 97.5%, and FIG. 2 shows the cell structure inside the polyurethane foam beads.
Example 2
The raw material is polyEther type TPU with a hardness of 85A and a density of 1.20g/cm3(@23 ℃) and the addition amount is 87.8 wt%; the mesh number of the PTFE solid powder is 400 meshes, and the addition amount is 6 wt%; the mesh number of the talcum powder is 5000 meshes, and the addition amount is 2 wt%; the supercritical fluid I is carbon dioxide with the purity of 99.9 percent, and the supercritical fluid II is nitrogen with the purity of 99.5 percent; the injection amount of carbon dioxide was 4.0 wt%, and the injection amount of nitrogen was 0.2 wt%.
The temperature of the double screw is set to be 200 ℃; the temperature of a charging barrel of the double-screw extruder is sequentially set from a hopper to an extrusion port to be 60-160-180-200-190-180 ℃, and the rotating speed of a screw is 40 revolutions per minute; the temperature of the static mixer was set to 160 ℃; the control pressure of the gear pump is set to be 16MPa, and the temperature of the gear pump is set to be 160 ℃; the temperature of the melt cooler was set at 140 ℃; the temperature of the extrusion die is set to be 140 ℃, and the pressure is set to be 16 MPa; the rotating speed of the underwater granulating cutter is set to be 800 revolutions per minute; the temperature of cooling water provided by the underwater pelletizing system is set to be 50 ℃, and the pressure of the cooling water is set to be 0.5 MPa.
By utilizing the extrusion foaming device and the process parameters, the prepared polyurethane bead foam has the foaming multiplying power of 10.8 times and the density of 0.11g/cm3The cells were uniform, the average cell diameter was 146.6 μm, and the closed cell ratio was 96%, and FIG. 3 shows the cell structure inside the polyurethane foam beads.
Example 3
The raw material is polyether TPU, the hardness of which is 95A, and the density of which is 1.20g/cm3(@23 ℃) and the addition amount is 89.6 wt%; the mesh number of the PTFE solid powder is 1000 meshes, and the addition amount is 3 wt%; the mesh number of the talcum powder is 5000 meshes, and the addition amount is 5 wt%; the supercritical fluid I is carbon dioxide with the purity of 99.9 percent, and the supercritical fluid II is nitrogen with the purity of 99.5 percent; the injection amount of carbon dioxide was 2.0 wt%, and the injection amount of nitrogen was 0.4 wt%.
The temperature of the double screws is set to be 220 ℃; the temperature of a charging barrel of the double-screw extruder is sequentially set from a hopper to an extrusion port to be 60-160-200-210-220-210-200-180 ℃, and the rotating speed of a screw is 25 revolutions per minute; the temperature of the static mixer was set at 170 ℃; the control pressure of the gear pump is set to be 20MPa, and the temperature of the gear pump is set to be 170 ℃; the temperature of the melt cooler was set to 145 ℃; the temperature of the extrusion die is set to 145 ℃, and the pressure is set to 25 MPa; the rotating speed of the underwater granulating cutter is set to 750 revolutions per minute; the temperature of cooling water provided by the underwater pelletizing system is set to be 60 ℃, and the pressure of the cooling water is set to be 0.6 MPa.
By utilizing the extrusion foaming device and the process parameters, the prepared polyurethane bead foam has the foaming multiplying power of 10.2 times and the density of 0.118g/cm3The cells were uniform, the average cell diameter was 22.8 μm, and the closed cell ratio was 98%, and FIG. 4 shows the cell structure inside the polyurethane foam beads.
Claims (22)
1. A method for preparing low-density TPU bead foam, which is prepared by extrusion foaming through coupling modification of polytetrafluoroethylene and talcum powder, wherein the method adopts the following material formula: 85-89.6wt% of TPU, 0.5-10 wt% of polytetrafluoroethylene, 0.5-8 wt% of talcum powder, 2-9 wt% of supercritical carbon dioxide and 0.1-0.6 wt% of supercritical nitrogen;
the method comprises the following steps:
(1) adding TPU, polytetrafluoroethylene and talcum powder into a charging barrel of a double-screw extruder of extrusion foaming equipment through a hopper;
(2) after the TPU is melted and is preliminarily mixed with the polytetrafluoroethylene and the talcum powder, sequentially and respectively injecting supercritical carbon dioxide and a certain amount of supercritical nitrogen into a charging barrel through two gas injection ports arranged on the charging barrel of a double-screw extruder;
(3) fully and uniformly mixing TPU, polytetrafluoroethylene, talcum powder and supercritical fluid in a double-screw extruder, then extruding, and then sequentially flowing through a static mixer, a gear pump, a melt cooler and an extrusion die which are arranged at the downstream of the double-screw extruder to extrude and foam;
(4) cutting the extruded foaming material into particles by an underwater particle cutting system, transporting and drying to finally obtain TPU bead foam;
the temperature of a mixing section of a charging barrel of the double-screw extruder is 170-240 ℃, the temperature of the static mixer is 140-190 ℃, the temperature of the gear pump is 140-190 ℃, the control pressure of the gear pump is 8-20 MPa, the temperature of the melt cooler is 100-160 ℃, the temperature of an extrusion opening die is 100-160 ℃, and the pressure of the extrusion opening die is 10-25 MPa.
2. The process of making a low density TPU bead foam of claim 1 wherein the TPU has a hardness of from 75A to 95A.
3. The method of making a low density TPU bead foam of claim 1, wherein the TPU has a hardness of from 80A to 90A.
4. The method of making a low density TPU bead foam of claim 1 wherein the material formulation has a polytetrafluoroethylene content of 1 to 8 weight percent.
5. The method of making a low density TPU bead foam of claim 1 wherein the material formulation has a polytetrafluoroethylene content of 2 to 6 weight percent.
6. The method of claim 1, wherein the talc is 1 to 6wt% of the material formulation.
7. The method of claim 1, wherein the talc is 2 to 5wt% of the material formulation.
8. The method of making a low density TPU bead foam of claim 1 wherein the material formulation has a supercritical carbon dioxide content of 3 to 6 weight percent.
9. The method of making a low density TPU bead foam of claim 1, wherein the supercritical nitrogen content of the material formulation is from 0.2 to 0.4 weight percent.
10. The process of making a low density TPU bead foam of claim 1 where the extrusion foaming apparatus comprises: the device comprises an extrusion mixing unit, a supercritical fluid injection unit, a static mixer, a gear pump, a melt cooler, an extrusion port die and an underwater pelletizing system; the extrusion mixing unit, the static mixing unit, the gear pump, the melt cooler, the extrusion port die and the underwater pelletizing system are sequentially connected in series; and the supercritical fluid injection unit is connected with the gas injection hole of the extrusion mixing unit through a pipeline.
11. The method for preparing a low density TPU bead foam of claim 10 where the extrusion compounding unit is a twin screw extruder consisting essentially of an extruder motor, twin screws, a barrel, a hopper, a screw temperature controller, a barrel heating element; 2 gas injection holes are sequentially formed in a charging barrel of the double-screw extruder; a heating and cooling unit is arranged outside the charging barrel of the double-screw extruder and is connected with a charging barrel temperature controller; a temperature control pipeline is arranged in a screw of the double-screw extruder and is connected with a screw temperature controller; the diameter of the screw is 27mm, and the length-diameter ratio is 50;
the supercritical fluid injection unit comprises two sets of supercritical fluid injection devices I and II, and each set of supercritical fluid injection device consists of a storage tank, a fluid pressure regulating metering pump and a connecting pipeline;
a shunting module, a mixing module and a converging module are arranged inside the static mixer;
the melt cooler comprises a melt flow micro-pipeline and a temperature control fluid medium flow micro-pipeline inside;
the extrusion die comprises 8 extrusion holes, and the aperture is 2.5 mm; the extrusion die is provided with a pressure monitoring unit;
the underwater pelletizing system consists of a cooling water circulating device, an underwater pelletizing motor, an underwater pelletizing cutter, a drying device and connecting pipelines among the underwater pelletizing cutter and the drying device.
12. The method of preparing a low density TPU bead foam of claim 11 where the temperature of the mixing section of the twin screw extruder barrel is 180 to 220 ℃.
13. The process of preparing a low density TPU bead foam of claim 11, wherein the static mixer has a temperature of from 150 to 170 ℃.
14. The process of preparing a low density TPU bead foam of claim 11 wherein the gear pump temperature is from 150 to 170 ℃.
15. The process for preparing a low density TPU bead foam of claim 11 wherein the gear pump is controlled at a pressure of from 10 to 15 MPa.
16. The process for preparing a low density TPU bead foam of claim 11 wherein the melt cooler temperature is from 120 ℃ to 145 ℃.
17. The method of making a low density TPU bead foam of claim 11, wherein the temperature of the extrusion die is from 120 ℃ to 145 ℃.
18. The method of making a low density TPU bead foam of claim 11 wherein the pressure of the extrusion die is from 12 to 20 MPa.
19. The method of preparing a low density TPU bead foam of claim 11, wherein the system temperature of the underwater pelletizing device is from 10 ℃ to 80 ℃.
20. The method of preparing a low density TPU bead foam of claim 11, wherein the system temperature of the underwater pelletizing device is from 30 ℃ to 60 ℃.
21. The method of making a low density TPU bead foam of claim 11, wherein the system pressure of the underwater pelletizing system is from 0.2 to 0.8 MPa.
22. The method of making a low density TPU bead foam of claim 11, wherein the system pressure of the underwater pelletizing system is from 0.3 to 0.6 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811093164.8A CN109320952B (en) | 2018-09-19 | 2018-09-19 | Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811093164.8A CN109320952B (en) | 2018-09-19 | 2018-09-19 | Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109320952A CN109320952A (en) | 2019-02-12 |
| CN109320952B true CN109320952B (en) | 2021-03-16 |
Family
ID=65264883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811093164.8A Active CN109320952B (en) | 2018-09-19 | 2018-09-19 | Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109320952B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7036391B2 (en) * | 2019-10-15 | 2022-03-15 | オトラジェット インコーポレイテッド． | Extrusion system and extrusion method |
| CN110919895A (en) * | 2019-11-07 | 2020-03-27 | 湖南工业大学 | Polylactic acid foaming micro-bead preparation device and preparation process thereof |
| CN111205632A (en) * | 2020-02-28 | 2020-05-29 | 山东大学 | Preparation method of thermoplastic polyurethane foam with adjustable density |
| EP4164854A1 (en) * | 2020-06-10 | 2023-04-19 | Basf Se | Microcellular foaming process for producing low density thermoplastic polyurethane foam |
| CN114211715A (en) * | 2021-12-28 | 2022-03-22 | 安徽东远新材料有限公司 | System and method for preparing foaming material |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101423615A (en) * | 2007-10-29 | 2009-05-06 | 文彦飞 | A kind of method that improves thermoplastic polymer fused mass strength |
| WO2012146676A1 (en) * | 2011-04-27 | 2012-11-01 | Basf Se | Extruded plastic profiled elements containing continuously inserted damping elements |
| CN103709726A (en) * | 2013-12-17 | 2014-04-09 | 烟台开发区新龙华包装材料有限公司 | Extrusion foaming thermoplastic polyurethane elastomer bead and preparation method thereof |
| CN105431268A (en) * | 2013-08-02 | 2016-03-23 | 耐克创新有限合伙公司 | Low density foamed articles and methods for making |
| CN106239766A (en) * | 2016-08-16 | 2016-12-21 | 湖北民族学院 | A kind of continuous extruding granulator of supercritical fluid |
| CN107075163A (en) * | 2014-08-26 | 2017-08-18 | 阿迪达斯股份公司 | Expanded polyamide pellet and the method that moulding part is manufactured using it |
| CN107828205A (en) * | 2017-11-02 | 2018-03-23 | 福建安达福新材料科技有限公司 | It is a kind of can vulcanization crosslinking polyurathamc elastomeric compound particle and preparation method thereof and moulding process |
| CN108239386A (en) * | 2016-12-26 | 2018-07-03 | 万华化学集团股份有限公司 | A kind of extrusion foaming thermoplastic polyurethane elastomer particle and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8551378B2 (en) * | 2009-03-24 | 2013-10-08 | North Carolina State University | Nanospinning of polymer fibers from sheared solutions |
-
2018
- 2018-09-19 CN CN201811093164.8A patent/CN109320952B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101423615A (en) * | 2007-10-29 | 2009-05-06 | 文彦飞 | A kind of method that improves thermoplastic polymer fused mass strength |
| WO2012146676A1 (en) * | 2011-04-27 | 2012-11-01 | Basf Se | Extruded plastic profiled elements containing continuously inserted damping elements |
| CN105431268A (en) * | 2013-08-02 | 2016-03-23 | 耐克创新有限合伙公司 | Low density foamed articles and methods for making |
| CN103709726A (en) * | 2013-12-17 | 2014-04-09 | 烟台开发区新龙华包装材料有限公司 | Extrusion foaming thermoplastic polyurethane elastomer bead and preparation method thereof |
| CN107075163A (en) * | 2014-08-26 | 2017-08-18 | 阿迪达斯股份公司 | Expanded polyamide pellet and the method that moulding part is manufactured using it |
| CN106239766A (en) * | 2016-08-16 | 2016-12-21 | 湖北民族学院 | A kind of continuous extruding granulator of supercritical fluid |
| CN108239386A (en) * | 2016-12-26 | 2018-07-03 | 万华化学集团股份有限公司 | A kind of extrusion foaming thermoplastic polyurethane elastomer particle and preparation method thereof |
| CN107828205A (en) * | 2017-11-02 | 2018-03-23 | 福建安达福新材料科技有限公司 | It is a kind of can vulcanization crosslinking polyurathamc elastomeric compound particle and preparation method thereof and moulding process |
Non-Patent Citations (3)
| Title |
|---|
| 《In-situ fibrillated polytetrafluoroethylene (PTFE) in thermoplastic polyurethane (TPU) via melt blending: Effect on rheological behavior, mechanical properties, and microcellular foamability》;Huang, An .etal;《POLYMER 》;ELSEVIER;20171124;第134卷;第263-274页 * |
| 《lightweight and tough nanocellular PP/PTFE nanocomposite foams with defect-free surfaces obtained using in situ nanofibrillation and nanocellular injection molding》;guilong wang .etal;《CHEMICAL ENGINEERING JOURNAL 》;Elseviver;20180528;第350卷;第1-11页 * |
| 《Polylactide/thermoplastic polyurethane/polytetrafluoroethylene nanocomposites with in situ fibrillated polytetrafluoroethylene and nanomechanical properties at the interface using atomic force microscopy》;AnHuang .etal;《Polymer Testing》;Elsevier;20180212;第67卷;第22-30页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109320952A (en) | 2019-02-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109320952B (en) | Method for preparing low-density TPU bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder | |
| CN109228003B (en) | Device and method for preparing low-density polymer foam beads by extruding and foaming supercritical mixed fluid | |
| CN111253677B (en) | Low-density polypropylene bead foam, and preparation method and application thereof | |
| CN109776848B (en) | Method and device for directly preparing polylactic acid foamed product from polylactic acid polymerization melt | |
| JP4460074B2 (en) | Injection molding of microporous materials | |
| CN103057059B (en) | Injection molding device and injection molding method of online mixing and preparing high-performance microcellular foaming plastic | |
| CN102869484A (en) | Method for producing composite pellet for extrusion molding, and composite pellet for extrusion molding produced by the method | |
| CN109435194B (en) | Be used for thermoplastic polyester foaming forming device | |
| JP5457933B2 (en) | Method for producing composite pellet for extrusion molding, and composite pellet for extrusion produced by the above method | |
| CN107216517B (en) | Preparation method of ultrahigh molecular weight polyethylene 3D printing supplies | |
| JP2680045B2 (en) | Extruder line for making foamable synthetic mixtures | |
| CN108715019B (en) | Internal inflation type extrusion foaming device and forming method | |
| CN113910485B (en) | Biodegradable polymer beads, preparation method and equipment | |
| CN111171366B (en) | Low-density polypropylene bead foam and preparation method and application thereof | |
| CN109228005B (en) | Method for preparing low-density TPU bead foam by extrusion foaming based on coupling modification of ultrahigh molecular weight polyethylene and talcum powder | |
| CN203077566U (en) | Injection moulding device for on-line mixing preparation of high-performance microcellular foaming plastic | |
| CN109228004B (en) | Method for preparing low-density PEBA bead foam through extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder | |
| CN109955452A (en) | A kind of isotactic polypropylene extrusion foaming device and technique | |
| CN212288259U (en) | Device for continuously preparing foamed thermoplastic polyurethane elastomer beads | |
| US9724857B2 (en) | Compression molded polymeric foam articles and methods | |
| CN206154534U (en) | Automatic plastics prilling granulator | |
| CN110919895A (en) | Polylactic acid foaming micro-bead preparation device and preparation process thereof | |
| CN109228250A (en) | A kind of method that multistage extruder granulation prepares low-cost and high-performance rubber plastic blend hole infiltrating irrigation | |
| CN106273053A (en) | A kind of low temperature powder body Granulation Equipments and method | |
| CN209937635U (en) | Preparation device of polylactic acid foaming product |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20230417 Address after: 351254 No.229 Haixiang Road, Hai'an village, Fengting Town, Xianyou County, Putian City, Fujian Province Patentee after: FUJIAN XINRUI NEW MATERIAL TECHNOLOGY Co.,Ltd. Address before: 351254 No.229 Haixiang Road, Hai'an village, Fengting Town, Xianyou County, Putian City, Fujian Province Patentee before: FUJIAN XINRUI NEW MATERIAL TECHNOLOGY Co.,Ltd. Patentee before: SHANDONG University |
|
| PE01 | Entry into force of the registration of the contract for pledge of patent right | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of invention: Preparation of low density TPU bead foam by extrusion foaming based on coupling modification of polytetrafluoroethylene and talcum powder Effective date of registration: 20230925 Granted publication date: 20210316 Pledgee: China Co truction Bank Corp Xianyou branch Pledgor: FUJIAN XINRUI NEW MATERIAL TECHNOLOGY Co.,Ltd. Registration number: Y2023350000208 |