A novel nested structure of polyphenyl ether / polystyrene foamed beads and a preparation method thereof
By introducing polypropylene and polytetrafluoroethylene into polyphenylene ether/polystyrene foam beads to form a nested structure, the problem of high foaming temperature of polyphenylene ether was solved, and efficient foaming and uniform closed-cell structure were prepared at low temperature.
Patent Information
- Application Number
- CN202510109725.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-11-07
- Estimated Expiration
- 2045-01-23
AI Technical Summary
In the existing technology, the foaming temperature of polyphenylene ether foam beads is high, which makes foaming difficult and results in poor foaming effect.
By introducing polypropylene into polyphenylene ether/polystyrene foam beads to form a nested structure and using polytetrafluoroethylene as a heterogeneous nucleating agent, the composition of foaming raw materials and process parameters are optimized, the foaming temperature is reduced, and the gas sealing performance is improved.
Good foaming performance of polyphenylene ether/polystyrene foam beads was achieved at a relatively low temperature, resulting in a uniform closed-cell structure with a maximum foaming ratio of 7.6 times and a closed-cell rate of 97%.
Smart Images
Figure CN119859359B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of microporous foaming of high polymer materials, and particularly relates to a novel polyphenyl ether / polystyrene foaming bead with a nested structure and a preparation method thereof. BACKGROUND
[0002] Polyphenyl ether (PPO) is a high-strength engineering material, which has good temperature resistance, electrical insulation, wear resistance and excellent flame resistance. It has a very large application market in electronic components, automobile parts, household appliances and the like. However, due to its high processing temperature, it is limited in many fields of popularization and application. The viscosity of polystyrene (PS) is much smaller than that of PPO, and the compatibility of PPO is good, which is often used to adjust the viscosity of PPO to meet the foaming demand.
[0003] The supercritical carbon dioxide autoclave foaming technology is a kind of foaming technology that uses carbon dioxide to form a uniform porous structure in the polymer material by high-temperature impregnation of the foaming material in the reaction kettle and rapid pressure relief, which can produce foam materials, and can well reduce the apparent density of the polymer while giving consideration to its good physical properties, so as to achieve the purpose of lightweight material. The products produced by this technology are mostly transported in the form of particles, and can be molded into various products by steam molding when used, which has better practicality and processability than conventional injection molding and molding foaming.
[0004] The use of supercritical carbon dioxide autoclave foaming technology to prepare polyphenyl ether foaming beads can achieve the purpose of lightweight material, but in the process of obtaining polyphenyl ether foaming beads, a relatively high foaming temperature is usually required, so that the polyphenyl ether foaming is difficult. SUMMARY
[0005] In view of the deficiencies of the prior art, the present application provides a novel polyphenyl ether / polystyrene foaming bead with a nested structure and a preparation method thereof. By optimizing the raw materials, adding polytetrafluoroethylene to increase the adsorption effect of the material on carbon dioxide, and using the sea-island structure formed by polypropylene in the polyphenyl ether / polystyrene matrix, the foaming bubble structure is redesigned after foaming, so that the bubble hole with a polypropylene film inside and a polyphenyl ether / polystyrene structure outside is obtained, the foaming temperature required for the polyphenyl ether foaming bead is reduced, and the problem of high foaming temperature of the polyphenyl ether foaming bead in the prior art is solved.
[0006] The technical scheme of the present application is as follows:
[0007] The first aspect of the present application protects a novel nested structure of polyphenyl ether / polystyrene foaming beads, the raw materials of the polyphenyl ether / polystyrene foaming beads, by mass percentage, include the following raw material components: 40-85% polystyrene, 5-40% polyphenyl ether, 5-20% polypropylene, 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, 0.1-0.3% dispersant.
[0008] Preferably, the polyphenyl ether / polystyrene foaming beads, by mass percentage, include the following raw material components: 70-85% polystyrene, 5-15% polyphenyl ether, 5-15% polypropylene, 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, 0.1-0.3% dispersant.
[0009] Preferably, the mass ratio of the polyphenyl ether to the polypropylene is 1-2:1.
[0010] Preferably, the polyphenyl ether is obtained by drying the polyphenyl ether raw material.
[0011] Preferably, the heterogeneous nucleating agent includes at least one of polytetrafluoroethylene, zinc borate, and talc; preferably, the heterogeneous nucleating agent is polytetrafluoroethylene, and the particle size of the polytetrafluoroethylene is 1-20 μm.
[0012] Preferably, the antioxidant includes one or more of antioxidant 1010, antioxidant 168, and antioxidant 1076; and the dispersant includes one or two of kaolin, butter, and montmorillonite.
[0013] The second aspect of the present application protects a preparation method of the novel nested structure of polyphenyl ether / polystyrene foaming beads of the first aspect, the preparation method includes the following steps, by mass fraction:
[0014] S1: mix polyphenyl ether, polystyrene, polypropylene, heterogeneous nucleating agent, and antioxidant, stir uniformly, add to an extruder for blending and extrusion, cool and draw after extrusion, and granulate by using a granulator to obtain polyphenyl ether / polystyrene pre-foaming particles;
[0015] S2: place the polyphenyl ether / polystyrene pre-foaming particles of step S1 in a reaction kettle, add a dispersant, set the temperature of the reaction kettle to 140-160°C, and the pressure to 1.0-4.0 MPa, and introduce a foaming agent into the reaction kettle, heat and pressurize to foam, then depressurize, and dry to obtain the novel nested structure of polyphenyl ether / polystyrene foaming beads.
[0016] Preferably, in step S1, the stirring speed is 100-500 r / min, and the stirring time is 10-30 min; the extruder has an extruding temperature of 160-260 DEG C and a rotating speed of 10-30 r / min; and the rotating speed of the granulator is 500-800 r / min.
[0017] Preferably, in step S1, the diameter of the polyphenyl ether / polystyrene pre-foaming microparticle is 0.5-1.5 mm, the length is 1.8-2.5 mm, and the single particle mass is 0.5-2.0 mg.
[0018] Preferably, in step S2, the foaming agent comprises at least one of CO2, N2, supercritical CO2 and supercritical N2; the heating and pressurizing time is 30-60 min; and the depressurizing rate is 2-5 MPa / s.
[0019] The present application has the beneficial technical effects that:
[0020] The present application realizes physical foaming by cooperation of polyphenyl ether and polypropylene and with the assistance of polytetrafluoroethylene, and improves the problems of difficulty in gas storage, poor foamability and high foaming temperature. The chain segment of polyphenyl ether is rigid, and the internal gas expands in the instant of foaming, and a certain gas sealing performance is needed to ensure that the particle can be successfully expanded. However, when the temperature is lower than 160 DEG C, the rigid chain segment of polyphenyl ether is difficult to effectively seal the gas, resulting in a large amount of internal gas escaping during foaming and poor foaming effect. The present application introduces polypropylene, which exists in the form of nested structure in the cell, and serves as an effective nucleation point for PPO / PS foaming, thereby improving the defects of PPO / PS such as difficulty in gas storage, poor foamability and high foaming temperature, and achieving good gas sealing effect at a lower foaming temperature, and improving the foaming performance of PPO / PS.
[0021] The present application controls the foaming raw materials and process, successfully prepares PPO / PS bead foams with controllable cell size, foam density and cell density, and the obtained polyphenyl ether / polystyrene foaming beads have a uniform closed cell structure, and the foaming ratio is up to 7.6 times, and the closed cell ratio is up to 97%. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 Figure 1 is a diagram of the internal cell structure of the PPO / PS bead foams prepared in Example 1 of the present application.
[0023] Figure 2 Figure 2 is a diagram of the internal structure of the PPO / PS pre-foaming microparticles in Example 1 of the present application. DETAILED DESCRIPTION
[0024] The present application will be specifically described below in combination with examples.
[0025] The first aspect of the present application provides a novel nested structure of polyphenyl ether / polystyrene foaming beads, and a preparation raw material of the polyphenyl ether / polystyrene foaming beads, which comprises the following raw material components in percentage by mass: 40-85% polystyrene (PS), 5-40% polyphenyl ether (PPO), 5-20% polypropylene (PP), 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, and 0.1-0.3% dispersant.
[0026] The present application realizes physical foaming by polypropylene and polyphenyl ether in cooperation with polytetrafluoroethylene, and improves the problems of difficult gas storage, poor expandability, high foaming temperature and the like in foaming. The chain segment of polyphenyl ether is strong in rigidity, and the internal gas expands in the instant of foaming, and a certain gas sealing performance is required to ensure that the particles can be successfully expanded. However, when the temperature is lower than 160 DEG C, the rigid chain segment of polyphenyl ether is difficult to effectively seal the gas, resulting in a large amount of internal gas escaping during foaming, and the foaming effect is poor. By introducing polypropylene, the polypropylene exists in the form of a nested structure in the cell, and serves as an effective nucleation point for PPO / PS foaming, thereby improving the disadvantages of difficult gas storage, poor expandability, high foaming temperature and the like of PPO / PS, and achieving good gas sealing effect at a lower foaming temperature, and improving the foaming performance of PPO / PS.
[0027] In some embodiments, the polyphenyl ether / polystyrene foaming beads comprise the following raw material components in percentage by mass: 70-85% polystyrene, 5-15% polyphenyl ether, 5-15% polypropylene, 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, and 0.1-0.3% dispersant.
[0028] In some embodiments, the mass ratio of the polyphenyl ether to the polypropylene is 1-2:1. By controlling the relative amount of polyphenyl ether and polypropylene, the formation of the cell structure is regulated. When there is too much polyphenyl ether and too little polypropylene, the foaming ratio is low, and the cell diameter is small. When there is too little polyphenyl ether and too much polypropylene, the cells are excessively expanded, and a large number of cells are combined and ruptured.
[0029] The polyphenyl ether is obtained by drying polyphenyl ether raw materials.
[0030] In some embodiments, the polyphenyl ether is pure polyphenyl ether powder.
[0031] In some embodiments, the heterogeneous nucleating agent comprises at least one of polytetrafluoroethylene, zinc borate, and talc; preferably, the heterogeneous nucleating agent is polytetrafluoroethylene.
[0032] In some embodiments, the particle size of the polytetrafluoroethylene is 1-20 μm, including but not limited to 1 μm, 5 μm, 10 μm, 15 μm, and 20 μm.
[0033] It can be understood that the heterogeneous nucleating agent PTFE used in the application has good affinity for carbon dioxide, and can adsorb more gas under the same conditions, which is beneficial to the formation of cells. Although the drying link before processing has little effect on the overall foaming, small bubbles are more likely to appear in the internal of the raw material without drying during the processing.
[0034] In some embodiments, the antioxidant includes one or more of antioxidant 1010, antioxidant 168, antioxidant 1076; the dispersant includes one or two of kaolin, butter, and montmorillonite.
[0035] The second aspect of the application protects a preparation method of the novel nested structure polyphenyl ether / polystyrene foaming beads of the first aspect, which comprises the following steps:
[0036] S1: mix polyphenyl ether, polystyrene polypropylene, heterogeneous nucleating agent, and antioxidant by mass fraction, stir uniformly, add to an extruder for blending and extrusion, cool and draw after extrusion, and granulate by a granulator to obtain polyphenyl ether / polystyrene pre-foaming particles;
[0037] S2: place the polyphenyl ether / polystyrene pre-foaming particles of step S1 in a reaction kettle, add a dispersant, set the temperature of the reaction kettle to 140-160℃, including but not limited to 140℃, 150℃, and 160℃, the pressure is 1.0-4.0MPa, including but not limited to 1.0MPa, 2MPa, 3MPa, and 4MPa, and a foaming agent is introduced into the reaction kettle, and after heating and pressurized foaming, the pressure is released, and dried to obtain the novel nested structure polyphenyl ether / polystyrene foaming beads.
[0038] In some embodiments, in step S1, the stirring speed is 100-500r / min, including but not limited to 100r / min, 200r / min, 300r / min, 400r / min, and 500r / min, and the time is 10-30min, including but not limited to 10min, 15min, 20min, 25min, and 30min; the extruder has an extrusion temperature of 160-260℃, including but not limited to 160℃, 180℃, 200℃, 220℃, 240℃, and 260℃, and a rotation speed of 10-30r / min, including but not limited to 10r / min, 15r / min, 20r / min, 25r / min, and 30r / min; and the granulator has a rotation speed of 500-800r / min, including but not limited to 500r / min, 600r / min, 700r / min, and 800r / min.
[0039] In some embodiments, in step S1, the polyphenyl ether / polystyrene pre-foaming microparticle has a diameter of 0.5-1.5mm, including but not limited to 0.5mm, 1.0mm, 1.5mm, a length of 1.8-2.5mm, including but not limited to 1.8mm, 2.0mm, 2.2mm, 2.5mm, and a single particle mass of 0.5-2.0mg, including but not limited to 0.5mg, 1.0mg, 1.5mg, 2.0mg.
[0040] In some embodiments, in step S2, the foaming agent includes at least one of CO2, N2, supercritical CO2, supercritical N2; the time of heating and pressurizing is 30-60min, including but not limited to 30min, 40min, 50min, 60min; and the rate of depressurization is 2-5MPa / s, including but not limited to 2MPa / s, 3MPa / s, 4MPa / s, 5MPa / s.
[0041] It can be understood that the present application reduces the foaming temperature, and good foaming performance material can be obtained at a lower foaming temperature. In the scheme of the present application, when the foaming temperature exceeds the defined range, a large number of cells may be ruptured because the glass transition temperature of PP is clear, and the temperature is increased. If the strength of PPO is insufficient, the molding may be failed.
[0042] The present application successfully prepares PPO / PS bead foams with controllable cell size, foam density and cell density by controlling the foaming raw material and process. The obtained polyphenyl ether / polystyrene foaming beads have a uniform closed cell structure, and the highest foaming ratio is 7.6 times, the foaming density is 0.132g / cm 3 , the average cell size is about 36μm, and the closed cell rate reaches 97%.
[0043] The present application is further illustrated by examples.
[0044] Example 1
[0045] A PPO / PS bead foam, the raw materials for preparing the bead foam include the following components in percentage by mass: PPO 10%, PS 83.4%, PP 5%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. Wherein, the PS is PG-33(2) from Zhenjiang Qimei Chemical Co., Ltd.; the PPO is LXN035 from Nantong Xingchen Synthetic Material Co., Ltd.; the PP is FL7540L from Singapore Polypropylene Co., Ltd. (tpc); the heterogeneous nucleating agent is PTFE, which is provided by Nanjing Tianshi New Material Co., Ltd., and the particle size is 5 μm. The antioxidant is antioxidant 1010. The dispersant is a mixture of kaolin and butter, and the mass ratio of kaolin to butter is 1:1. The foaming agent is CO2, and the purity is 99.9%, which is provided by Linde CO2 Co., Ltd.
[0046] The preparation of the above PPO / PS bead foam includes the following steps:
[0047] (1) In percentage by mass, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added into a high-speed blender, and stirred at a speed of 500 r / min for 20 min, and then added into a twin-screw extruder for melt blending. The extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210 ℃ in turn, and the rotating speed is 20 r / min. After underwater cooling and drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min.
[0048] (2) The prepared PPO / PS pre-foaming particle is added into a reaction kettle, and kaolin and butter are added. The temperature of the reaction kettle is set to 145 ℃, and the pressure is 4 MPa. CO2 is introduced into the reaction kettle through the gas inlet of the reaction kettle for heating and pressurizing. After the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that the PPO / PS bead foam can be obtained.
[0049] The microstructure of the PPO / PS pre-foaming particle prepared in step 1 of this embodiment is photographed by a scanning electron microscope, and the result is shown in Figure 2 As can be seen from Figure 2 , the polypropylene forms a sea-island structure in the polyphenyl ether / polystyrene matrix.
[0050] The internal cell structure of the PPO / PS bead foam prepared in step (2) of Example 1 is photographed by a scanning electron microscope, and the result is shown in Figure 1 As can be seen from the above photograph, the foaming particle prepared in this example has a cell structure with a polypropylene film inside and a polyphenyl ether / polystyrene structure outside.
[0051] Example 2
[0052] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 15%, PS 74.4%, PP 9%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturer model of each raw material is the same as example 1.
[0053] The preparation of the PPO / PS bead foam includes the following steps:
[0054] (1) PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added into a high-speed mixer by mass percentage, stirred at a speed of 500 r / min for 20 min, mixed uniformly, and then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-210-230-240-240-230-210°C in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0055] (2) The prepared PPO / PS pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145°C, and the pressure is 4 MPa, CO2 is introduced into the reaction kettle through the gas inlet on the reaction kettle for heating and pressurizing, after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that a PPO / PS bead foam can be obtained.
[0056] Example 3
[0057] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 15%, PS 74.4%, PP 9%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturer model of each raw material is the same as example 1.
[0058] The preparation of the PPO / PS bead foam includes the following steps:
[0059] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added into a high-speed mixer, stirred at a speed of 500 r / min for 20 min, mixed uniformly, then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-210-230-240-240-230-210℃ in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0060] (2) The prepared PPO / PS pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145℃, and the pressure is 4 MPa, CO2 is introduced into the reaction kettle through the gas inlet of the reaction kettle for heating and pressurizing, after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that a PPO / PS bead foam can be obtained.
[0061] Example 4
[0062] A PPO / PS bead foam, the raw materials of the bead foam include the following components in mass percentage: PPO 15%, PS 68.4%, PP 15%, heterogeneous nucleating agent 0.5%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturers and models of each raw material are the same as those in Example 1.
[0063] The preparation of the PPO / PS bead foam includes the following steps:
[0064] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added into a high-speed mixer, stirred at a speed of 500 r / min for 20 min, mixed uniformly, then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-210-230-240-240-230-210℃ in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0065] (2) The prepared PPO / PS pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145℃, and the pressure is 4 MPa, CO2 is introduced into the reaction kettle through the gas inlet of the reaction kettle for heating and pressurizing, after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that a PPO / PS bead foam can be obtained.
[0066] Example 5
[0067] A PPO / PS bead foam, the raw materials for preparing the bead foam include the following components by mass percentage: PPO 10%, PS 83.4%, PP 5%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. Among them, PS is PG-33(2) of Zhenjiang Qimei Chemical Co., Ltd.; PPO is LXN035 of Nantong Xingchen Synthetic Material Co., Ltd.; PP is FL7540L of Singapore Polypropylene Co., Ltd. (tpc); the heterogeneous nucleating agent is PTFE, which is provided by Nanjing Tianshi New Material Co., Ltd., and the particle size is 5 μm. The antioxidant is antioxidant 168. The dispersant is a mixture of kaolin and butter, and the mass ratio of kaolin to butter is 1:1. The foaming agent is CO2, with a purity of 99.9%, which is provided by Linde CO2 Co., Ltd.
[0068] The preparation of the above PPO / PS bead foam includes the following steps:
[0069] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added to a high-speed mixer, stirred at a speed of 100 r / min for 30 min, mixed uniformly, and then added to a twin-screw extruder for melt blending. The extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210℃ in turn, and the rotating speed is 10 r / min; after underwater cooling and drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 700 r / min.
[0070] (2) The prepared PPO / PS pre-foaming particle is added to a reaction kettle, and kaolin and butter are added. The temperature of the reaction kettle is set to 140℃, and the pressure is 1.0 MPa. CO2 is introduced into the reaction kettle through the gas inlet on the reaction kettle for heating and pressurizing. After the PPO / PS / PP particles are saturated with CO2 for 30 min, the pressure is released to normal atmospheric pressure at a rate of 3 MPa / s, and then dried to obtain a PPO / PS bead foam.
[0071] Example 6
[0072] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 10%, PS 83.4%, PP 5%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. Among them, PS is PG-33(2) of Zhenjiang Qimei Chemical Co., Ltd.; PPO is LXN035 of Nantong Xingchen Synthetic Material Co., Ltd.; PP is FL7540L of Singapore Polypropylene Co., Ltd. (tpc); the heterogeneous nucleating agent is PTFE, which is provided by Nanjing Tianshi New Material Co., Ltd., and the particle size is 5 μm. The antioxidant is antioxidant 1076. The dispersant is a mixture of kaolin and butter, and the mass ratio of kaolin to butter is 1:1. The foaming agent is CO2, and the purity is 99.9%, which is provided by Linde CO2 Co., Ltd.
[0073] The preparation of the above PPO / PS bead foam includes the following steps:
[0074] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 are added into a high-speed mixer, stirred at a speed of 300 r / min for 20 min, mixed uniformly, and then added into a twin-screw extruder for melt blending. The extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210℃ in turn, and the rotating speed is 30 r / min; after underwater cooling and drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 800 r / min.
[0075] (2) The prepared PPO / PS pre-foaming particle is added into a reaction kettle, and kaolin and butter are added. The temperature of the reaction kettle is set to 160℃, and the pressure is 3 MPa. CO2 is introduced into the reaction kettle through the gas inlet of the reaction kettle for heating and pressurizing. After the PPO / PS / PP particle is saturated with CO2 for 60 min, it is depressurized to normal atmospheric pressure at a rate of 5 MPa / s, and then dried to obtain a PPO / PS bead foam.
[0076] Comparative Example 1
[0077] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 10%, PS 83.4%, PP 5%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturers and models of the raw materials are the same as in Example 1. Comparative Example 1 does not add PP compared with Example 1.
[0078] The preparation of the PPO / PS bead foam includes the following steps:
[0079] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, antioxidant 1010 are added into a high-speed mixer, stirred at a speed of 500 r / min for 20 min, mixed uniformly, then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210 °C in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0080] (2) The prepared PPO / PS / PP pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145 °C, and the pressure is 4 MPa, CO2 is introduced into the reaction kettle through the gas inlet on the reaction kettle for heating and pressurizing, after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that a PPO / PS bead foam can be obtained.
[0081] Comparative Example 2
[0082] A PPO / PS bead foam board, the raw materials of the bead foam board include the following components by mass percentage: PPO 10%, PS 88.4%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturers and models of each raw material are the same as those in Example 1. The foaming temperatures of Comparative Example 1 and Comparative Example 2 are different.
[0083] The preparation of the PPO / PS bead foam board includes the following steps:
[0084] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, antioxidant 1010 are added into a high-speed mixer, stirred at a speed of 500 r / min for 20 min, mixed uniformly, then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210 °C in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0085] (2) The prepared PPO / PS / PP pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145 °C, and the pressure is 4 MPa, CO2 is introduced into the reaction kettle through the gas inlet on the reaction kettle for heating and pressurizing, after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, so that a PPO / PS bead foam can be obtained.
[0086] Comparative Example 3
[0087] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 15%, PS 74.5%, PP 9%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturer model of each raw material is the same as Example 1. The amount of heterogeneous nucleating agent PTFE used in Comparative Example 3 is different from that of Example 2.
[0088] The preparation of the PPO / PS bead foam includes the following steps:
[0089] (1) PPO, PS, PP, antioxidant 1010 are added into a high-speed mixer by mass percentage, stirred at a speed of 500 r / min for 20 min, mixed uniformly, and then added into a twin-screw extruder for melt blending, the extrusion temperature interval of the twin-screw extruder is 190-200-220-240-240-230-210°C in turn, and the rotating speed is 20 r / min; after underwater cooling and wire drawing, a PPO / PS pre-foaming particle is prepared by a granulator, wherein the rotating speed of the granulator is 500 r / min;
[0090] (2) The prepared PPO / PS / PP pre-foaming particle is added into a reaction kettle, and kaolin and butter are added, the temperature of the reaction kettle is set to 145°C, and the pressure is 4 MPa; CO2 is introduced into the reaction kettle through the gas inlet on the reaction kettle for heating and pressurizing; after the PPO / PS / PP particle is saturated with CO2 for 45 min, the pressure is released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried, thereby obtaining a PPO / PS bead foam.
[0091] Comparative Example 4
[0092] A PPO / PS bead foam, the raw materials of the bead foam include the following components by mass percentage: PPO 15%, PS 74.4%, PP 9%, heterogeneous nucleating agent 0.1%, antioxidant 1010 1.2%, dispersant 0.3%. The manufacturer model of each raw material is the same as Example 1. Compared with Example 2, the polyphenyl ether raw material of Comparative Example 4 is not dried at 90°C.
[0093] The preparation of the PPO / PS bead foam includes the following steps:
[0094] (1) According to the mass percentage, PPO, PS, heterogeneous nucleating agent PTFE, PP, antioxidant 1010 were added into a high-speed blender, stirred at a speed of 500 r / min for 20 min, mixed uniformly, and then added into a twin-screw extruder for melt blending. The extrusion temperature interval of the twin-screw extruder was 190-210-230-240-240-230-210°C, and the rotation speed was 20 r / min. After underwater cooling and drawing, a PPO / PS pre-foaming particle was prepared by a granulator, wherein the rotation speed of the granulator was 500 r / min.
[0095] (2) The prepared PPO / PS pre-foaming particle was added into a reaction kettle, and kaolin and butter were added. The temperature of the reaction kettle was set to 145°C, and the pressure was 4 MPa. CO2 was introduced into the reaction kettle through the gas inlet to heat and pressurize. After the PPO / PS / PP particle was saturated with CO2 for 45 min, the pressure was released to normal atmospheric pressure at a rate of 2 MPa / s, and then dried to obtain a PPO / PS bead foam.
[0096] Test Example:
[0097] The PPO / PS foaming beads prepared in Examples 1-4 and Comparative Examples 1-4 were observed by scanning electron microscopy, and the average cell size was counted by ImagePro software. The closed cell rate was measured by a true density instrument according to the GB / T10799-2008 standard, and the foam density and foaming ratio of the PPO / PS foaming beads were measured by the drainage method. The results are shown in Table 1.
[0098] Table 1 Comparison of properties of bead foams prepared in Examples 1-2 and Comparative Examples 1-4 of the application
[0099]
[0100]
[0101] From Table 1, it can be seen that by using CO2 as a foaming agent, PTFE as a nucleating agent, and PP as a cell size modifier, PPO / PS foam particles with uniform cell size and high foaming ratio can be prepared at a lower foaming temperature; compared with the foaming material without PP, the foaming ratio is significantly improved after adding PP at the same foaming temperature, because the PP molecular chain is flexible and has a good sealing effect on the gas. At the same time, PS and PPO are relatively rigid, which can effectively act as a support structure for PP, and the nested structure formed by the cooperation of the two can achieve excellent foaming effect. At the same time, different amounts of PP can effectively control the cell size, which is convenient for making foaming particles with different cell sizes. From Comparative Example 3, it can be seen that because the heterogeneous nucleating agent PTFE has good affinity for carbon dioxide, it can adsorb more gas under the same conditions, which is more conducive to the formation of cells. Comparative Example 4 does not dry the polyphenyl ether raw material, which has little effect on the overall foaming, but small bubbles are more likely to occur inside the raw material during processing, leading to problems such as broken wires during wire drawing.
[0102] The above only describes the preferred embodiments of the present application, and the present application is not limited to the above examples. It can be understood that other improvements and changes directly derived or thought of by those skilled in the art without departing from the spirit and concept of the present application should be considered to be within the scope of protection of the present application.
Claims
1. A nested structure of polyphenylene ether / polystyrene expanded beads characterized by, The polyphenyl ether / polystyrene foaming beads comprise the following raw material components by mass percentage: 40-85% polystyrene, 5-40% polyphenyl ether, 5-20% polypropylene, 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, and 0.1-0.3% dispersant. The polyphenyl ether is obtained by drying polyphenyl ether raw materials; The heterogeneous nucleating agent is polytetrafluoroethylene. The dispersant is a mixture of kaolin and butter.
2. The polyphenylene ether / polystyrene expanded bead of claim 1, wherein, The polyphenyl ether / polystyrene foaming beads comprise the following raw material components by mass percentage: 70-85% polystyrene, 5-15% polyphenyl ether, 5-15% polypropylene, 0.1-5% heterogeneous nucleating agent, 0.5-1.2% antioxidant, and 0.1-0.3% dispersant.
3. The polyphenylene ether / polystyrene expanded bead of claim 1, wherein, The mass ratio of the polyphenyl ether to the polypropylene is 1-2:
1.
4. The polyphenylene ether / polystyrene expanded bead of claim 1, wherein, The particle size of the polytetrafluoroethylene is 1-20 μm.
5. The polyphenylene ether / polystyrene expanded bead of claim 1, wherein, The antioxidant comprises one or more of antioxidant 1010, antioxidant 168, and antioxidant 1076.
6. A process for the production of the nested polyphenylene ether / polystyrene expanded bead of any one of claims 1 to 5, characterized in that, The preparation method comprises the following steps by mass fraction: S1: mixing polyphenyl ether, polystyrene, polypropylene, heterogeneous nucleating agent, and antioxidant, stirring uniformly, adding to an extruder for blending and extruding, cooling and drawing after extrusion, and granulating by a granulator to obtain polyphenyl ether / polystyrene pre-foaming particles; S2: placing the polyphenyl ether / polystyrene pre-foaming particles of step S1 in a reaction kettle, adding a dispersant, setting the temperature of the reaction kettle to 140-160°C and the pressure to 1.0-4.0 MPa, and introducing a foaming agent into the reaction kettle, and then heating and pressurizing to foam, releasing pressure, and drying to obtain polyphenyl ether / polystyrene foaming beads with a nested structure.
7. The production method according to claim 6, characterized by, In step S1, the stirring speed is 100-500 r / min and the stirring time is 10-30 min; the extruder has an extruding temperature of 160-260°C and a rotating speed of 10-30 r / min; and the granulator has a rotating speed of 500-800 r / min.
8. The preparation method according to claim 6, characterized in that, In step S1, the polyphenyl ether / polystyrene pre-foaming particles have a diameter of 0.5-1.5 mm, a length of 1.8-2.5 mm, and a single particle mass of 0.5-2.0 mg.
9. The preparation method according to claim 6, characterized in that, In step S2, the foaming agent comprises at least one of CO2, N2, supercritical CO2, and supercritical N2. The heating and pressurizing time is 30-60 min, and the pressure release rate is 2-5 MPa / s.
Citation Information
Patent Citations
Polyphenylene ether resin composition and molded article
CN117642466A
Polypropylene resin foamed product
JP1994256555A