A high-density polyester foam board and its preparation method

Abstract

The present invention discloses a high-density polyester foam board and a preparation method thereof, belonging to the technical field of material synthesis. The high-density polyester foam board comprises the following components in parts by mass: 60-75 parts of polyester, 10-20 parts of a filling masterbatch, 5-10 parts of a chain extender, 2-5 parts of a nucleating agent, and 4-7 parts of a foaming agent; the filling masterbatch comprises the following components: a carrier resin, a filler, a dispersant, and a coupling agent. The high-density polyester foam board of the present invention has an extremely high density, high mechanical strength, excellent thermal stability, a high closed-cell rate, and small cell sizes. The filling masterbatch is conducive to the heterogeneous nucleation of polyester, endows polyester with foamability, improves the melt rigidity, enables the cells to form a closed-cell structure, enhances the material density and mechanical strength, and meets the strength of bearing loads and the weather and heat resistance required by structural components.

Description

Technical Field

[0001] The present invention relates to the technical field of material synthesis, specifically to the technical field of foam boards. Further, it relates to a high-density polyester foam board, and even further, it also relates to a preparation method of the high-density polyester foam board. Background Art

[0002] Due to the overexploitation of forest resources, the ecological environment has deteriorated severely and a large amount of soil and water has been lost. China has effectively controlled the timber resources. However, with the development of China's economy, the demand for wood by people is increasing continuously. To solve the supply-demand problem, people begin to pay attention to the field of composite materials and advocate using plastics instead of wood. Therefore, high-density foaming materials have received more attention in the fields of building materials, rail transit, etc.

[0003] High-density foaming materials can be used alone or in combination with reinforcing materials such as glass fiber. They have the advantages of high strength, good toughness, uniform cell structure, dense and tough skin, high production efficiency, environmental protection and energy saving, etc. Moreover, they can adjust the color according to the appearance of the product and endow the board with functionality through methods such as surface skinning and spraying. Therefore, high-density foam boards have broad market prospects.

[0004] PET has excellent properties such as oil resistance, chemical corrosion resistance, easy recyclability, high mechanical properties, and good fatigue resistance. It is widely used in various fields of people's daily life and plays an irreplaceable role. After foaming, the PET board has an excellent performance-cost ratio. It has the characteristics of light weight, high specific strength, excellent cushioning performance, etc. At the same time, compared with other foam materials, it also has the advantages of high-temperature stability, excellent mechanical properties, fatigue resistance, and biodegradability. Therefore, PET foam boards are widely used in the fields of refrigerated truck body panels, wind power, aviation containers, electric logistics vehicles, rail transit, construction, etc. After China launched the natural forest protection project, it is extremely urgent to develop a method for continuously preparing high-density PET foam boards.

[0005] The high-density foam board is a material formed by continuous extrusion and foaming through a special process. Its surface forms a uniform hard film, and the interior is composed of completely closed-cell foams continuously and evenly. The high-density foam board has compressive resistance, light weight, and water absorption resistance. However, the technical disadvantages of continuously preparing high-density PET foam boards are mainly divided into two aspects: On the one hand, the unmodified PET foam board has low mechanical strength and cannot meet the requirements of rigid plastics. The low melt strength makes the cell walls of PET foam prone to rupture, which will lead to the merging and collapse of cells. Therefore, the finally prepared foam board has a low foaming rate and a high open-cell rate, and it is difficult to meet the requirements of structural applications. At the same time, high-filling additives need to be added to the high-density foam board, and the dispersion state of the additives directly affects the material properties. On the other hand, the process of continuously extruding PET foam boards is complex and there are many post-treatment processes, which increases the preparation cost. The mainstream extrusion foaming process often selects a strip-shaped cylindrical extrusion die head. The polyester melt passing through the strip-shaped extrusion die head is cured and formed, and they are extruded and bonded together to prepare a PET foam board, which shows a honeycomb structure in the transverse direction. Subsequent four-sided planing treatment is required to make the surface of the foam board flat. Due to the strip-shaped structure of the die, the melt undergoes an orientation effect at the die head, making the cured PET foam anisotropic, and its performance in the transverse direction is significantly superior to that in the longitudinal and vertical directions. To improve the comprehensive performance of the material, after the PET foam board is extruded and formed and undergoes four-sided planing, it needs to be thermally combined and cut again, using the transverse direction with the strongest mechanical properties as the stress surface, which undoubtedly increases the production process and raises the preparation cost. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high-density polyester foam board and its preparation method. The foam board has an extremely high density, high mechanical strength, excellent thermal stability, a high closed-cell rate, and small cell sizes.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] In the first aspect, the present invention provides a high-density polyester foam board, which comprises the following components in parts by mass: 60 - 75 parts of polyester, 10 - 20 parts of filling masterbatch, 5 - 10 parts of chain extender, 2 - 5 parts of nucleating agent, 4 - 7 parts of foaming agent;

[0009] The filling masterbatch comprises the following components: carrier resin, filler, dispersant, coupling agent.

[0010] As a preferred embodiment of the present invention, the high-density polyester foam board comprises the following components in parts by mass: 65 - 71 parts of polyester, 14 - 20 parts of filling masterbatch, 5.5 - 9.5 parts of chain extender, 3 - 4 parts of nucleating agent, 5 - 6 parts of foaming agent.

[0011] As a preferred embodiment of the present invention, the high-density polyester foam board comprises the following components in parts by mass: 65 parts of polyester, 20 parts of a filling masterbatch, 5.5 parts of a chain extender, 4 parts of a nucleating agent, and 5 parts of a foaming agent.

[0012] As a preferred embodiment of the present invention, the filling masterbatch comprises the following components in parts by mass: 25 - 36 parts of a carrier resin, 60 - 70 parts of a filler, 3 - 4 parts of a dispersant, and 1 - 2 parts of a coupling agent.

[0013] As a preferred embodiment of the present invention, the filling masterbatch comprises the following components in parts by mass: 26 parts of a carrier resin, 70 parts of a filler, 3 parts of a dispersant, and 1 part of a coupling agent.

[0014] As a preferred embodiment of the present invention, the carrier resin comprises at least one of EAA, PE, LDPE, and LLDPE.

[0015] As a preferred embodiment of the present invention, the filler comprises at least one of calcium carbonate, talcum powder, white carbon black, montmorillonite, and diatomaceous earth, preferably montmorillonite.

[0016] As a preferred embodiment of the present invention, the dispersant comprises at least one of polyethylene wax and polypropylene wax.

[0017] As a preferred embodiment of the present invention, the coupling agent comprises at least one of a silane coupling agent, a carbonate coupling agent, and an aluminate coupling agent.

[0018] As a preferred embodiment of the present invention, the polyester comprises at least one of PET, rPET, PETG, PBT, PTT, PLA, PBAT, PGA, PHA, PCL, PCT, PCTG, and PC.

[0019] As a preferred embodiment of the present invention, the chain extender comprises at least one of an acrylic acid containing an epoxy functional group, an isocyanate, a polyfunctional epoxy resin, an acid anhydride compound, and a polycarbodiimide.

[0020] As a preferred embodiment of the present invention, the foaming agent comprises at least one of liquid carbon dioxide, n-pentane, neopentane, cyclopentane, n-hexane, liquid nitrogen, hydrofluorocarbons, and sodium bicarbonate.

[0021] As a preferred embodiment of the present invention, the nucleating agent is potassium N-butylpiperazide, and the particle size of the nucleating agent is less than 20 μm.

[0022] As a preferred embodiment of the present invention, it further comprises 0.5 - 1 part by mass of an antioxidant.

[0023] As a preferred embodiment of the present invention, the high-density polyester foam board is prepared by an extrusion device, and the extrusion device includes an extrusion die head, and the extrusion die head includes an upper die body and a lower die body. An extrusion die orifice is provided between the upper die body and the lower die body. The extrusion die orifice is sequentially provided with an inlet zone, a die orifice zone, a transition zone, and an outlet zone along the flow direction of the polyester melt, and the extrusion die orifice becomes narrower from wide along the flow direction of the polyester melt.

[0024] As a preferred embodiment of the present invention, the inlet zone includes a first inlet zone and a second inlet zone. The end faces of the first inlet zone and the second inlet zone are both rectangular, and the extrusion die orifice becomes narrower from wide along the first inlet zone to the second inlet zone;

[0025] The die orifice zone includes a first die orifice zone, a second die orifice zone, and a third die orifice zone. The first die orifice zone, the second die orifice zone, and the third die orifice zone are all trapezoidal, and become narrower from wide along the first die orifice zone to the third die orifice zone;

[0026] The transition zone is rectangular;

[0027] The outlet zone is trapezoidal.

[0028] As a preferred embodiment of the present invention, both the upper die body and the lower die body are provided with die body heating / cooling circulating oil channels and die lip heating / cooling circulating oil channels.

[0029] In a second aspect, the present invention also provides a method for preparing the above-mentioned high-density polyester foam board, including the following steps:

[0030] Adding the filling masterbatch and polyester into the extrusion equipment from the main feeding port, adding the chain extender and the nucleating agent from the side feeding port, injecting the foaming agent into the melt in the screw heating zone, and mixing evenly to obtain a polyester melt;

[0031] The polyester melt enters the extrusion die head through a static mixer, is pressurized and solidified through the extrusion die orifice, and then is drawn and transversely cut to obtain the high-density polyester foam board.

[0032] The beneficial effects of the present invention are as follows: (1) The product of the present invention has extremely high density, high mechanical strength, excellent thermal stability, high closed-cell rate, and small cell size; (2) The addition of the filler is conducive to the heterogeneous nucleation of polyester, endowing polyester with foamability, improving the melt rigidity, forming a closed-cell structure of the cells, enhancing the material density and mechanical strength, and meeting the strength and weather and heat resistance requirements of structural components; (3) By using the specific extrusion die head of the present invention, the melt first passes through the rectangular inlet area, then passes through the trapezoidal die area that gradually narrows from wide to narrow, then passes through the rectangular transition area, and finally passes through the trapezoidal outlet area, which can further improve the density, mechanical strength, thermal stability and closed-cell rate of the foam board, and reduce the cell size. The above-mentioned extrusion die head increases the melt pressure at the die head, which is conducive to the mutual extrusion of the melt in the die head, making the surface of the cured foam board flat and isotropic, eliminating the need for edge planing and heat sealing processes, reducing the process flow. When depressurizing, increasing the melt pressure causes mutual extrusion and surface skin formation, resulting in a high-density foam board with a smooth surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the device for preparing the high-density polyester foam board;

[0034] Figure 2 Schematic diagram of the structure of the extrusion die head of the present invention;

[0035] Figure 3 Enlarged schematic diagram of the outlet area.

[0036] 1. Extrusion die head; 2. Upper die body; 3. Lower die body; 4. Die body heating / cooling circulating oil channel; 5. Die lip heating / cooling circulating oil channel; 6. Extruder; 7. Front flange; 8. Static mixer; 9. Rear flange; 11. First inlet area; 12. Second inlet area; 13. First die area; 14. Second die area; 15. Third die area; 16. Transition area; 17. Outlet area. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0038] An embodiment of the present invention provides a high-density polyester foam board, which comprises the following components in parts by mass: 60-75 parts of polyester, 10-20 parts of filler masterbatch, 5-10 parts of chain extender, 2-5 parts of nucleating agent, 4-7 parts of foaming agent;

[0039] The filling masterbatch comprises the following components: carrier resin, filler, dispersant, coupling agent.

[0040] By combining the above various raw materials in a specific ratio, the present invention prepares a foam board with extremely high density, high mechanical strength, excellent thermal stability, high closed-cell rate, and small cell size.

[0041] Adding the filling masterbatch can significantly improve the density, mechanical strength, thermal stability, and closed-cell rate, and reduce the cell size compared with directly adding the filler.

[0042] Adding the filler in the form of the filling masterbatch can improve the dispersion performance of the filler in the formulation system, facilitate the heterogeneous nucleation of polyester, endow polyester with foamability, improve the melt rigidity, make the cells form a closed-cell structure, enhance the material density and mechanical strength, and meet the strength and weather and heat resistance requirements for load-bearing of structural components.

[0043] In one embodiment, the high-density polyester foam board comprises the following components in parts by mass: 65-71 parts of polyester, 14-20 parts of filling masterbatch, 5.5-9.5 parts of chain extender, 3-4 parts of nucleating agent, 5-6 parts of foaming agent.

[0044] By controlling the above raw materials within the above parts by mass, the density, mechanical strength, thermal stability, and closed-cell rate can be further improved, and the cell size can be reduced.

[0045] In one preferred embodiment, the high-density polyester foam board comprises the following components in parts by mass: 65 parts of polyester, 20 parts of filling masterbatch, 5.5 parts of chain extender, 4 parts of nucleating agent, 5 parts of foaming agent.

[0046] In one embodiment, the filling masterbatch comprises the following components in parts by mass: 25-36 parts of carrier resin, 60-70 parts of filler, 3-4 parts of dispersant, 1-2 parts of coupling agent.

[0047] In one preferred embodiment, the filling masterbatch comprises the following components in parts by mass: 26 parts of carrier resin, 70 parts of filler, 3 parts of dispersant, 1 part of coupling agent.

[0048] In one embodiment, the carrier resin comprises at least one of EAA, PE, LDPE, LLDPE.

[0049] In one embodiment, the filler comprises at least one of calcium carbonate, talcum powder, white carbon black, montmorillonite, diatomaceous earth, and is preferably montmorillonite.

[0050] In one embodiment, the dispersant comprises at least one of polyethylene wax and polypropylene wax.

[0051] In one embodiment, the coupling agent includes at least one of a silane coupling agent, a carbonate coupling agent, and an aluminate coupling agent.

[0052] In one embodiment, the polyester includes at least one of PET, rPET, PETG, PBT, PTT, PLA, PBAT, PGA, PHA, PCL, PCT, PCTG, and PC.

[0053] In one embodiment, the chain extender includes at least one of acrylic acid containing an epoxy functional group, isocyanate, polyfunctional epoxy resin, acid anhydride compound, and polycarbodiimide.

[0054] In one embodiment, the foaming agent includes at least one of liquid carbon dioxide, n-pentane, neopentane, cyclopentane, n-hexane, liquid nitrogen, hydrofluorocarbon, and sodium bicarbonate.

[0055] In one embodiment, the nucleating agent is potassium N-butylpiperazide, and the particle size of the nucleating agent is less than 20 μm.

[0056] In some specific examples, the high-density polyester foam board further includes 0.5 to 1 part by mass of an antioxidant.

[0057] In one embodiment, the high-density polyester foam board is prepared by an extrusion device. The extrusion device includes an extrusion die head, and the extrusion die head includes an upper die body and a lower die body. An extrusion die orifice is provided between the upper die body and the lower die body. The extrusion die orifice is sequentially provided with an inlet zone, a die orifice zone, a transition zone, and an outlet zone along the flow direction of the polyester melt, and the extrusion die orifice becomes narrower from wide along the flow direction of the polyester melt.

[0058] In one embodiment, the inlet zone includes a first inlet zone and a second inlet zone. The end faces of the first inlet zone and the second inlet zone are both rectangular, and the extrusion die orifice becomes narrower from wide along the first inlet zone to the second inlet zone;

[0059] The die orifice zone includes a first die orifice zone, a second die orifice zone, and a third die orifice zone. The first die orifice zone, the second die orifice zone, and the third die orifice zone are all trapezoidal, and become narrower from wide along the first die orifice zone to the third die orifice zone;

[0060] The transition zone is rectangular;

[0061] The outlet zone is trapezoidal.

[0062] By adopting the specific extrusion die of the present invention, the melt first passes through the inlet area of the rectangular structure, then passes through the trapezoidal die area that becomes narrower from wide, then passes through the rectangular transition area, and finally passes through the trapezoidal outlet area, which can further improve the density, mechanical strength, thermal stability and closed cell rate of the foam board, and reduce the bubble size. The above-mentioned extrusion die increases the melt pressure at the die head, which is conducive to the mutual extrusion of the melt in the die head, so that the surface of the solidified foam board is flat and isotropic, and there is no need for planing and heat sealing processes, which reduces the process flow. When the pressure is released, the melt pressure is increased, so that they are squeezed against each other and a skin is formed on the surface, thereby preparing a high-density foam board with a smooth surface.

[0063] In some specific examples, both the upper mold body and the lower mold body are provided with mold body heating / cooling circulation oil channels and die lip heating / cooling circulation oil channels.

[0064] One embodiment of the present invention provides a method for preparing the high-density polyester foam board described above, comprising the following steps:

[0065] Filling masterbatch and polyester are added to the extruder from the main feed port, chain extender and nucleating agent are added from the side feed port, and foaming agent is injected into the melt in the screw heating zone and mixed evenly to obtain polyester melt;

[0066] The polyester melt enters the extrusion die through a static mixer, is pressurized and solidified through the extrusion die, and then is pulled and cut horizontally to obtain a high-density polyester foam board.

[0067] In the present invention, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0068] In the present invention, unless otherwise stated, all parts are parts by mass.

[0069] The reagents or instruments used in the present invention, if the manufacturer is not indicated, are all conventional products that can be obtained commercially. The raw materials used in the examples and comparative examples of the present invention are as follows:

[0070] PET resin: brand name is CR-8816, manufacturer is China Resources Chemical Materials Technology Co., Ltd.

[0071] rPET resin: brand 4280T, manufacturer is Hebei Pingyuan New Material Technology Co., Ltd.

[0072] PETG resin: brand KN100, manufacturer is South Korea's SKY company.

[0073] Acrylate containing epoxy functional groups, brand 4468, manufactured by BASF, Germany.

[0074] Isocyanate (MDI): Brand: BP-5, manufacturer: Coase Chemical Co., Ltd.

[0075] Montmorillonite: Industrial grade, mesh number 800, manufacturer: Changzhou Rongao Chemical New Materials Co., Ltd.

[0076] Anhydride compound: Grade Celymer TM MDA, Dongguan Sanhe Chemical Co., Ltd.

[0077] LDPE: Grade LF2700, manufacturer: Shanghai Petrochemical Company.

[0078] LLDPE: Grade DNDA-7144, manufacturer: Shanghai Petrochemical Company.

[0079] PE: Grade 5000S, manufacturer: PetroChina Daqing Company.

[0080] Potassium N-butylpiperidinate: Particle size less than 20μm, grade JYN695, manufacturer: Guangzhou Yinuo Chemical Technology Co., Ltd.

[0081] Calcium carbonate: Industrial grade, mesh number 1000, Lingshou Baiyi Mineral Processing Factory.

[0082] Talc powder: Industrial grade, mesh number 1250, Qingdao Haishengyuan Minerals Co., Ltd.

[0083] Aluminate coupling agent: Grade ZTL-ALP-04, manufacturer: Yangzhou Zhongtianli New Materials Co., Ltd.

[0084] Titanate coupling agent: Grade WOT-108, Guangdong Weilinna New Materials Technology Co., Ltd.

[0085] Silane coupling agent: KH-560, manufacturer: Shandong Hengyu New Materials Co., Ltd.

[0086] Polyethylene wax: Grade AC-6A, manufacturer: Honeywell, USA.

[0087] Antioxidant: Grade 1010, manufacturer: BASF, Germany.

[0088] Filler masterbatch-1: Weigh LDPE, montmorillonite, silane coupling agent, and polyethylene wax according to the weight ratio of 26:70:3:1 respectively. Add LDPE, montmorillonite, silane coupling agent, and polyethylene wax to a high-speed mixer, stir at 10 rpm for 5 min, then stir at 60 rpm for 10 min, discharge the material, pour the material into the main feed port of a twin-screw extruder, the melt is sheared, extruded, and plasticized in the twin-screw, and circular strip-shaped material is extruded through the die head, cooled by a water cooling tank, and then pelletized by a pelletizer to obtain high-fill masterbatch-1.

[0089] Filler masterbatch - 2: Weigh PE, calcium carbonate, titanate coupling agent, and polyethylene wax according to the weight ratio of 35:60:3:2 respectively. Add PE, calcium carbonate, titanate coupling agent, and polyethylene wax into a high - speed mixer, stir at a speed of 10 rpm for 5 min, then stir at a speed of 60 rpm for 10 min, and discharge the material. Pour the material into the main feed port of a twin - screw extruder. The melt is sheared, extruded, and plasticized in the twin - screw, and circular strip - shaped material is extruded through the die head. After being water - cooled in a cooling water tank, it is granulated by a granulator to obtain high - filling masterbatch - 2.

[0090] Filler masterbatch - 3: Weigh PE, talcum powder, aluminate coupling agent, and polyethylene wax according to the weight ratio of 27:68:4:2 respectively. Add PE, talcum powder, aluminate coupling agent, and polyethylene wax into a high - speed mixer, stir at a speed of 10 rpm for 5 min, then stir at a speed of 60 rpm for 10 min, and discharge the material. Pour the material into the main feed port of a twin - screw extruder. The melt is sheared, extruded, and plasticized in the twin - screw, and circular strip - shaped material is extruded through the die head. After being water - cooled in a cooling water tank, it is granulated by a granulator to obtain high - filling masterbatch - 3.

[0091] The following further elaborates the present invention with specific embodiments:

[0092] Example 1

[0093] A high - density polyester foam board comprises the following components in parts by mass: 71 parts of PET resin, 14 parts of filler masterbatch - 1, 5.5 parts of acrylate containing epoxy functional groups, 4 parts of N - butyl piperidinium potassium salt, 5 parts of n - pentane, and 0.5 part of antioxidant.

[0094] Please refer to Figures 1 to 3 , the preparation method of the high - density polyester foam board is as follows: Dry the filler masterbatch - 1 at 60 °C for 5 h. Add the dried filler masterbatch - 1 and polyester into the extruder 6 from the main feed port, add the chain extender, nucleating agent, and antioxidant from the side feed port, and inject the foaming agent into the melt in the 5th zone of the screw heating area. Set the temperatures of heating zones 1 - 8 to 150 °C, 290 °C, 290 °C, 287 °C, 286 °C, 285 °C, 284 °C, and 275 °C respectively, and the screw speed to 150 r / min. The raw materials are fully melted, sheared, and mixed evenly in the screw to obtain a polyester melt (a solid - gas two - phase homogeneous system);

[0095] After the polyester melt passes through the extruder and undergoes shearing and extrusion by the high-temperature screw to form a homogeneous solid-gas two-phase system, it flows into the front flange 7 and is then pushed into the static mixer 8, flowing out from the rear flange 9 to the die head at a lower temperature. The melt is fully mixed in the static mixer. The pressure of the front flange is set to 6 MPa, and the pressure of the rear flange is set to 4 MPa. The pressure difference is conducive to the accumulation of pressure of the melt in the pipeline, providing energy for generating more dense foam cells during subsequent pressure relief and foaming. After the melt flows out of the rear flange, it is pushed into the extrusion die head, and pressure is relieved at the flat die head. The melt is in a thermodynamically unstable state, and heterogeneous nucleation occurs on the surface of the high filler, forming a large number of small holes, and being extruded and solidified at the flat die head. After that, it is pulled and transversely cut to prepare a high-density polyester foam board with a smooth surface.

[0096] The extrusion die head 1 includes an upper die body 2 and a lower die body 3. An extrusion die orifice is provided between the upper die body and the lower die body. The extrusion die orifice is successively provided with an inlet zone, a die orifice zone, a transition zone, and an outlet zone along the flow direction of the polyester melt, and the extrusion die orifice becomes narrower from wide along the flow direction of the polyester melt.

[0097] The inlet zone includes a first inlet zone 11 and a second inlet zone 12. The end faces of the first inlet zone 11 and the second inlet zone 12 are both rectangular, and the extrusion die orifice becomes narrower from wide along the first inlet zone to the second inlet zone.

[0098] The die orifice zone includes a first die orifice zone 13, a second die orifice zone 14, and a third die orifice zone 15. The first die orifice zone, the second die orifice zone, and the third die orifice zone are all trapezoidal, and they become narrower from wide along the first die orifice zone to the third die orifice zone.

[0099] The transition zone 16 is rectangular.

[0100] The outlet zone 17 is trapezoidal.

[0101] Both the upper die body and the lower die body are provided with a die body heating / cooling circulating oil channel 4 and a die lip heating / cooling circulating oil channel 5.

[0102] Example 2

[0103] A high-density polyester foam board comprises the following components in parts by mass: 68 parts of PET resin, 17 parts of filler masterbatch-1, 5.5 parts of acrylate containing epoxy functional groups, 4 parts of N-butylpyridinium potassium salt, 5 parts of n-pentane, and 0.5 part of antioxidant.

[0104] The preparation method of the high-density polyester foam board is the same as that in Example 1.

[0105] Example 3

[0106] A high-density polyester foam board, comprising the following components in parts by mass: 65 parts of PET resin, 20 parts of filler masterbatch-1, 5.5 parts of acrylate containing epoxy functional groups, 4 parts of N-butylpiperazine potassium salt, 5 parts of n-pentane, and 0.5 part of antioxidant.

[0107] The preparation method of the high-density polyester foam board is the same as that of Example 1.

[0108] Example 4

[0109] A high-density polyester foam board, comprising the following components in parts by mass: 65 parts of PET resin, 20 parts of filler masterbatch-2, 5.5 parts of acid anhydride compound, 4 parts of N-butylpiperazine potassium salt, 5 parts of n-pentane, and 0.5 part of antioxidant.

[0110] The preparation method of the high-density polyester foam board is the same as that of Example 1.

[0111] Example 5

[0112] A high-density polyester foam board, comprising the following components in parts by mass: 65 parts of PET resin, 18 parts of filler masterbatch-2, 7.5 parts of acid anhydride compound, 4 parts of N-butylpiperazine potassium salt, 5 parts of n-pentane, and 0.5 part of antioxidant.

[0113] The preparation method of the high-density polyester foam board is the same as that of Example 1.

[0114] Example 6

[0115] A high-density polyester foam board, comprising the following components in parts by mass: 65 parts of PET resin, 16 parts of filler masterbatch-2, 9.5 parts of acid anhydride compound, 4 parts of N-butylpiperazine potassium salt, 5 parts of n-pentane, and 0.5 part of antioxidant.

[0116] The preparation method of the high-density polyester foam board is the same as that of Example 1.

[0117] Example 7

[0118] A high-density polyester foam board, comprising the following components in parts by mass: 65 parts of rPET resin, 17 parts of filler masterbatch-3, 7.5 parts of MDI, 3 parts of N-butylpiperazine potassium salt, 6.5 parts of n-pentane, and 1 part of antioxidant.

[0119] The preparation method of the high-density polyester foam board is the same as that of Example 1.

[0120] Example 8

[0121] A high-density polyester foam board, comprising the following components in parts by mass: 60 parts of rPET resin, 20 parts of filler masterbatch-3, 10 parts of MDI, 5 parts of N-butylpiperazine potassium salt, 4 parts of n-pentane, and 1 part of antioxidant.

[0122] The preparation method of the high-density polyester foam board is the same as that in Example 1.

[0123] Example 9

[0124] A high-density polyester foam board comprises the following components in parts by mass: 75 parts of rPET resin, 10 parts of filler masterbatch-3, 5 parts of MDI, 5 parts of N-butylpyraclostrobin potassium salt, 4 parts of n-pentane, and 1 part of antioxidant.

[0125] The preparation method of the high-density polyester foam board is the same as that in Example 1.

[0126] Comparative Example 1

[0127] The difference between Comparative Example 1 and Examples 3 to 6 is that Comparative Example 1 does not contain filler masterbatch, and in the preparation process, a circular hole spinneret die is used, the circular hole specification is a hole diameter of 35 mm, 8 holes per row, two rows in total, and the die head width is 1300 mm. The other parts of the mold are the same as those in the examples, and the mold manufacturer is Shengshuo Precision Machinery (Changzhou) Co., Ltd.

[0128] A polyester foam board comprises the following components in parts by mass: 85 parts of PET resin, 5 parts of MDI, 5 parts of potassium salt of N-butylpyraclostrobin, 4 parts of n-pentane, and 1 part of an antioxidant.

[0129] Comparative Example 2

[0130] The difference between Comparative Example 2 and Examples 3 to 6 is that, during the preparation process, Comparative Example 2 adopts a cylindrical die head (same as Comparative Example 1), and all other aspects are the same.

[0131] Comparative Example 3

[0132] The difference between Comparative Example 3 and Examples 3 to 6 is that Comparative Example 3 does not contain filler masterbatch, and all other aspects are the same.

[0133] A polyester foam board comprises the following components in parts by mass: 85 parts of PET resin, 5 parts of MDI, 5 parts of potassium salt of N-butylpyraclostrobin, 4 parts of n-pentane, and 1 part of an antioxidant.

[0134] Comparative Example 4

[0135] The difference between Comparative Example 4 and Example 1 is that an equal amount of montmorillonite is used to replace the filler masterbatch-1 in Comparative Example 4, and all other aspects are the same.

[0136] A polyester foam board comprises the following components in parts by mass: 71 parts of PET resin, 14 parts of montmorillonite, 5.5 parts of acrylate containing epoxy functional groups, 4 parts of potassium salt of N-butylpyraclostrobin, 5 parts of n-pentane, and 0.5 parts of an antioxidant.

[0137] Test Case

[0138] The prepared foam board was cut into strip samples for mechanical and thermal tests.

[0139] Among them, the density, compressive strength, and tensile strength were tested according to ISO844.

[0140] The shear strength was tested according to ISO1922.

[0141] The flexural strength was tested according to GB / T 1456-2006.

[0142] The heat distortion temperature was tested according to ASTM D648.

[0143] The closed cell rate was tested according to GB / T 10799.

[0144] The nail-holding power was tested according to GB / T17657-2013.

[0145] The test results are shown in Table 1.

[0146] Table 1

[0147]

[0148] It can be seen from Table 1 that the polyester foam board described in the present invention has an extremely high density, high mechanical strength, excellent thermal stability, high closed cell rate, and small cell size.

[0149] By comparing Examples 1 to 9, it can be seen that in the present invention, Example 3 is the best embodiment with the best performance.

[0150] By comparing the examples with Comparative Examples 1 to 4, it can be seen that in the present invention, adding the filler in the form of a masterbatch can significantly increase the density, mechanical strength, thermal stability, and closed cell rate of the polyester foam board, and reduce the cell size; further using the specific extrusion die head described in the present invention to prepare the foam board can further increase the density, mechanical strength, thermal stability, and closed cell rate of the foam board, and reduce the cell size. [[ID={40]]

[0151] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A high-density polyester foam board, characterized in that, It comprises the following components in parts by mass: 60 to 75 parts of polyester, 10 to 20 parts of filler masterbatch, 5 to 10 parts of chain extender, 2 to 5 parts of nucleating agent, and 4 to 7 parts of foaming agent; The filler masterbatch comprises the following components: 25 to 36 parts of carrier resin, 60 to 70 parts of filler, 3 to 4 parts of dispersant, and 1 to 2 parts of coupling agent; The nucleating agent is potassium N-butylpiperazide, and the particle size of the nucleating agent is less than 20 μm; The carrier resin comprises at least one of EAA, PE, LDPE, and LLDPE; The filler comprises at least one of calcium carbonate, talcum powder, white carbon black, montmorillonite, and diatomite; The high-density polyester foam board is prepared by an extrusion device, and the extrusion device comprises an extrusion die head. The extrusion die head comprises an upper die body and a lower die body. An extrusion die orifice is arranged between the upper die body and the lower die body. The extrusion die orifice is sequentially provided with an inlet zone, a die orifice zone, a transition zone, and an outlet zone along the flowing direction of the polyester melt, and the extrusion die orifice becomes narrower from wide along the flowing direction of the polyester melt.

2. The high-density polyester foam board according to claim 1, characterized in that, It comprises the following components in parts by mass: 65 to 71 parts of polyester, 14 to 20 parts of filler masterbatch, 5.5 to 9.5 parts of chain extender, 3 to 4 parts of nucleating agent, and 5 to 6 parts of foaming agent.

3. The high-density polyester foam board according to claim 1, which comprises the following components in parts by mass: 65 parts of polyester, 20 parts of filler masterbatch, 5.5 parts of chain extender, 4 parts of nucleating agent, and 5 parts of foaming agent.

4. The high-density polyester foam board according to claim 1, wherein The filler masterbatch comprises the following components in parts by mass: 26 parts of carrier resin, 70 parts of filler, 3 parts of dispersant, and 1 part of coupling agent.

5. The high-density polyester foam board according to claim 4, wherein At least one of the following (a) to (b): (a) The dispersant comprises at least one of polyethylene wax and polypropylene wax; (b) The coupling agent comprises at least one of silane coupling agent, carbonate coupling agent, and aluminate coupling agent.

6. The high-density polyester foam board according to claim 1, characterized in that, At least one of the following (1) to (3): (1) The polyester comprises at least one of PET, rPET, PETG, PBT, PTT, PLA, PBAT, PGA, PHA, PCL, PCT, PCTG, and PC; (2) The chain extender comprises at least one of acrylic acid containing epoxy functional group, isocyanate, polyfunctional epoxy resin, acid anhydride compound, and polycarbodiimide; (3) The foaming agent comprises at least one of liquid carbon dioxide, n-pentane, neopentane, cyclopentane, n-hexane, liquid nitrogen, hydrofluorocarbon, and sodium bicarbonate.

7. The high-density polyester foam board according to claim 1, characterized in that, It further comprises 0.5 to 1 part by mass of antioxidant.

8. The high-density polyester foam board according to claim 7, wherein The inlet zone comprises a first inlet zone and a second inlet zone. The end faces of the first inlet zone and the second inlet zone are both rectangular, and the extrusion die orifice becomes narrower from wide along the first inlet zone to the second inlet zone; The die orifice zone comprises a first die orifice zone, a second die orifice zone, and a third die orifice zone. The first die orifice zone, the second die orifice zone, and the third die orifice zone are all trapezoidal, and the extrusion die orifice becomes narrower from wide along the first die orifice zone to the third die orifice zone; The transition zone is rectangular; The outlet zone is trapezoidal.

9. The high-density polyester foam board according to claim 7, wherein Both the upper die body and the lower die body are provided with die body heating / cooling circulating oil channels and die lip heating / cooling circulating oil channels.

10. The preparation method of the high-density polyester foam board according to any one of claims 1 to 9, characterized in that, It comprises the following steps: The masterbatch and polyester are added into the extrusion equipment from the main feeding port, the chain extender and nucleating agent are added from the side feeding port, and the foaming agent is injected into the melt in the screw heating zone and mixed evenly to obtain a polyester melt; The polyester melt enters the extrusion die through a static mixer, is pressurized and solidified through the extrusion die, and then is drawn and transversely cut to obtain a high-density polyester foam board.

Images