Polyarylether composite foam material and preparation method thereof

Abstract

The invention provides a polyarylether composite foam material and a preparation method thereof. The preparation method comprises the following steps: impregnating chopped carbon fibers in an SBS solution, and carrying out surface coating treatment to obtain modified chopped carbon fibers; the dipping temperature is 100-150 DEG C, and the dipping time is 1-10 minutes; premixing the modified short carbon fiber with PAE and SBS resin to obtain a mixture; and carrying out extrusion foaming treatment on the mixture, and then carrying out flattening treatment and traction treatment to obtain the polyarylether composite foam material. Wherein based on the total mass of the PAE and the SBS resin being 100%, the addition amount of the short carbon fibers is 1%-8%. The short carbon fibers are coated with SBS, the SBS and PAE have good compatibility, the interaction between the short carbon fibers and a PAE / SBS matrix is indirectly improved, and the prepared PAE composite foam material has better mechanical properties.

Description

Technical Field

[0001] The invention relates to a polyarylether composite foam material and a preparation method thereof, belonging to the technical field of polymer materials. Background Art

[0002] Polyarylether (PAE) is an engineering plastic with excellent thermal stability, electrical insulation and chemical stability, and is widely used in high-performance fields. However, pure PAE materials have obvious defects in processability and foaming properties, which limits their application in foam materials. Although PAE has good compatibility with styrene-butadiene-styrene triblock copolymer (SBS), PAE foam materials are usually prepared by blending, but this method brings new problems: after blending PAE with SBS, the mechanical properties of PAE foam materials decrease significantly, especially in terms of compressive strength, which cannot meet the needs of practical applications.

[0003] With the development of modern science and technology, the requirements for compression strength of foam materials are getting higher and higher to cope with more stringent use environments and load conditions. The current PAE foam materials are still insufficient in compression strength, which is its biggest bottleneck. Therefore, in-depth research on the mechanical properties, processability, foaming properties and other aspects of PAE foam materials will bring huge application value to the industrial field and promote the widespread application of PAE foam materials in high strength, high pressure resistance and other fields.

[0004] However, the preparation of high-compression PAE foam materials still faces the following technical difficulties that need to be overcome: (1) Conventional inorganic fillers have limited reinforcing effects on improving material properties and are difficult to meet increasingly stringent performance requirements; (2) The interfacial bonding force between the filler and the matrix is ​​weak, and there is no interaction (hydrogen bonding / ionic bonding / covalent bonding), resulting in poor compatibility. This problem needs to be solved urgently to ensure the overall performance and stability of the composite material; (3) Factors such as the type of polymer selected for polymer coating, impregnation time, and impregnation temperature will affect the coating effect and thus affect the dispersion of the filler in the matrix; (4) The addition of fillers will inevitably affect the rheological properties and foaming properties of the matrix. Therefore, appropriate processing conditions are required to obtain polyarylether composite foam materials with high compressive strength.

[0005] In view of this, it is of great significance to develop a new and efficient reinforcing filler to break through the performance bottleneck of existing fillers and thus improve the mechanical properties of foam materials. Summary of the invention

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide a polyarylene ether composite foam material and a preparation method thereof, wherein the prepared polyarylene ether composite foam material has better mechanical properties.

[0007] To achieve the above object, in a first aspect, the present invention provides a method for preparing a polyarylene ether composite foam material, which comprises the following steps:

[0008] Step 1: immersing the chopped carbon fiber in an SBS solution for surface coating to obtain modified chopped carbon fiber (SCF); wherein the immersion temperature is 100-150° C. and the immersion time is 1-10 min;

[0009] Step 2: premixing the modified chopped carbon fiber with PAE and SBS resin to obtain a mixture;

[0010] Step 3: Extruding and foaming the mixture, and then flattening and pulling the mixture to obtain a polyarylether composite foam material;

[0011] Wherein, based on the total mass of PAE and SBS resin being 100%, the addition amount of the chopped carbon fiber is 1%-8%.

[0012] The present invention can achieve good dispersion of chopped carbon fibers by coating the surface of polymer SBS. SBS has good compatibility with PAE. After surface treatment, the SBS molecular chains on the chopped carbon fibers will diffuse with the PAE molecular chains during processing to form a stable phase, thereby indirectly improving the interaction between the carbon fibers and the PAE / SBS matrix, improving the interface bonding force, significantly improving its mechanical properties and thermal stability, and realizing continuous production of polyarylether composite foam materials.

[0013] In the preparation method of the polyarylether composite foam material, preferably, the addition amount of the chopped carbon fiber is 2%-6%, more preferably 4%-6%, based on the total mass of PAE and SBS resin as 100%. If the addition amount of the chopped carbon fiber is too large, it may cause the structure of the foam material to be uneven, affecting the distribution and shape of the pores, and too high nucleation efficiency may lead to the merging and rupture of the pores, thereby reducing the closed cell rate; at the same time, the comprehensive cost of the material increases, which is not conducive to economic benefits; in addition, excessive carbon fiber will affect the rheological properties of the material, resulting in processing difficulties during extrusion and foaming, thereby reducing processing efficiency and making it difficult to form the product.

[0014] In the method for preparing the polyarylene ether composite foam material, preferably, in step 1, the mass ratio of the chopped carbon fiber to the SBS in the SBS solution is 1:(3-20), more preferably 1:(5-15).

[0015] In the preparation method of the above-mentioned polyarylene ether composite foam material, preferably, the diameter of the chopped carbon fiber is ≤7μm, and the length of the chopped carbon fiber is ≤3mm; more preferably, the diameter of the chopped carbon fiber is ≤4μm, and the length of the chopped carbon fiber is ≤2mm. The chopped carbon fiber used in the present invention has a smaller diameter and a shorter length, which is conducive to better dispersion; at the same time, the chopped carbon fiber with a shorter length can provide a stronger nucleation effect during the foaming process, thereby optimizing the pore structure. If the length of the chopped carbon fiber is too long and the nucleation effect is too strong, pore merging may occur, thereby reducing the closed cell rate and compression strength; if the diameter of the chopped carbon fiber is large, defect points are easily formed during the compression process, destroying the pore structure, thereby reducing the compression strength of the overall polyarylene ether composite foam material.

[0016] In the preparation method of the above-mentioned polyarylether composite foam material, preferably, in step 1, the temperature of immersing the chopped carbon fiber in the SBS solution is 100-120°C. If the temperature of immersing the chopped carbon fiber in the SBS solution in the present invention is too low, the SBS in the impregnation solution cannot be completely melted, and the portion in contact with the chopped carbon fiber is small, resulting in poor volume expansion effect. If the impregnation temperature is too high, due to the low viscosity and excessive fluidity of SBS, it is not easy to coat the surface of the chopped carbon fiber, thereby affecting the modification effect of the chopped carbon fiber.

[0017] In the method for preparing the polyarylene ether composite foam material, preferably, the time for immersing the chopped carbon fibers in the SBS solution is 8-10 minutes.

[0018] In the preparation method of the above-mentioned polyarylene ether composite foam material, preferably, in step one, the chopped carbon fiber is immersed in an SBS solution, and after surface coating treatment, an ultrasonic dispersion process is further included for 1-3 hours and then drying. More preferably, the ultrasonic dispersion time is 2 hours.

[0019] In the preparation method of the above-mentioned polyarylether composite foam material, preferably, in step 2, based on the total mass of PAE and SBS resin as 100%, the mass fraction of the SBS resin is 40%-60%; preferably, the mass fraction of the SBS resin is 45%-55%. When the SBS content is too high, although the foaming performance is better, the performance of the polyarylether composite foam material is more inclined to SBS, which may be detrimental to the overall performance of the composite material. When the SBS content is too low, in the continuous extrusion foaming, the viscosity of the matrix is ​​too large, which will make the foam material difficult to shape and it is difficult to obtain a complete polyarylether composite foam material. The polyarylether composite foam material obtained by the method provided by the present invention can ensure the melt strength of the matrix during the continuous extrusion foaming process, and the processing difficulty of extrusion foaming is also relatively low.

[0020] In the preparation method of the polyarylether composite foam material, preferably, an antioxidant is also added, premixed with the PAE / SBS resin and the modified short-cut carbon fiber, and then added together to the extrusion foaming unit. Based on the mass fraction of the PAE and SBS resins as 100%, the amount of the antioxidant added is 0.5%-2%, more preferably 1%.

[0021] In the preparation method of the polyarylether composite foam material, preferably, the antioxidant is antioxidant 245, specifically triethylene glycol ether-di(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate.

[0022] In the preparation method of the polyarylether composite foam material, preferably, in step 2, the temperature at which the modified chopped carbon fiber is premixed with the PAE and SBS resins is 190-210° C., more preferably 200-210° C. If the premixing temperature is too high, the thermal stability of the SBS molecular chain is poor, and it will degrade to varying degrees without being mixed with the PAE molecular chain, thereby affecting the performance of the final foam material; if the temperature is too low, the glass transition temperature of the PAE molecular chain cannot be reached, the movement of the molecular chain is difficult, and PAE and SBS cannot form a stable phase. In thermodynamics, if the two materials are not separated into phases, there is no distinction between a dispersed phase and a continuous phase, and the two are regarded as existing in one phase.

[0023] In the method for preparing the polyarylene ether composite foam material, preferably, in step 2, the time for premixing the modified chopped carbon fiber with the PAE and SBS resins is 5-10 minutes, more preferably 8-10 minutes.

[0024] In the above method for preparing the polyarylene ether composite foam material, preferably, in step three, the mixture is subjected to extrusion foaming treatment by a twin-screw extrusion foaming unit.

[0025] In the method for preparing the polyarylether composite foam material, preferably, in step 3, the feeding temperature of the mixture for extrusion foaming is 60-80° C., and the blending temperature for extrusion foaming is 160-220° C. The blending process is continuously carried out in the melting stage, the gas dissolution stage, and the cooling stage.

[0026] In the preparation method of the above-mentioned polyarylene ether composite foam material, preferably, in step three, the temperatures of various parts of the mixture subjected to extrusion foaming treatment are set to 60-80°C, 200-220°C, 190-210°C, 190-210°C, 190-210°C, 180-200°C, 160-190°C, 160-190°C; more preferably, the feeding temperature of the feeding section of the twin-screw extrusion foaming unit is set to 60-80°C, the temperature of the melting section is set to 200-220°C, the temperature of the gas dissolution section is set to 190-210°C, the temperature of the cooling section is set to 180-200°C, 160-190°C; and the head temperature is set to 160-180°C. The present invention adds the above mixture to a twin-screw extrusion foaming unit through a hopper, first passes through a plasticizing section, and injects a physical foaming agent into the twin-screw extrusion foaming unit through an air injection pump to obtain a premix, and the gas dissolution section is after the air inlet; then the premix enters a static mixer for static mixing to reduce the melt temperature and increase the melt strength; finally, the melt is extruded from a die for foaming, and then cooled and shaped. If the overall system temperature of the twin-screw extrusion foaming unit is too low, the melt viscosity is too large, and a sheet with a foaming ratio of five times cannot be produced, and the material can hardly be foamed; if the temperature is too high, the melt temperature will also be too high, and the melt strength of PAE will be lower at high temperatures, resulting in an inability to produce a complete foam material. More preferably, the physical foaming agent is carbon dioxide.

[0027] In the preparation method of the polyarylether composite foam material, preferably, in step 3, the rotation speed of the twin-screw extrusion foaming unit used for extruding and foaming the mixture is 80-120 rad / min, more preferably 80-100 rad / min. Since the melt viscosity of PAE itself is relatively high, if the rotation speed during extrusion is too low, the fluidity of the material will be restricted, resulting in poor flow of the material during extrusion, increasing the system pressure of the entire extrusion foaming unit, and the expansion power at the exit die is large, and the cell growth power is too strong, so that the cell rupture occurs, and the foam closed cell rate is lower.

[0028] The present invention optimizes parameters such as temperature and rotation speed of extrusion foaming treatment to increase the twin-screw extrusion temperature, thereby solving the problem of flow obstruction caused by increased viscosity.

[0029] In the above-mentioned method for preparing the polyarylene ether composite foam material, preferably, in step three, the temperature of the flattening treatment is set to 60-100°C; more preferably, the material extruded from the die head is passed through a flattening machine to make the surface of the obtained polyarylene ether composite foam material flat.

[0030] In the preparation method of the above polyarylether composite foam material, preferably, in step three, the traction speed of the traction treatment is 1-2 m / min; more preferably, the traction equipment is used to cool and shape the material through a fan on the bracket to finally obtain the desired foam material.

[0031] In the above method for preparing the polyarylether composite foam material, preferably, in step three, the rotation speed of the traction treatment is 900-2000 rad / min.

[0032] In a second aspect, the present invention further provides a polyarylene ether composite foam material prepared by the above-mentioned method for preparing the polyarylene ether composite foam material.

[0033] In the above polyarylene ether composite foam material, preferably, the average cell size of the polyarylene ether composite foam material is 300-400 μm.

[0034] In the above polyarylene ether composite foam material, preferably, the closed cell rate of the polyarylene ether composite foam material is 80%-83%.

[0035] In the above polyarylene ether composite foam material, preferably, the compressive strength of the polyarylene ether composite foam material is 1.9-2.5 MPa.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The present invention first immerses the short carbon fiber in an SBS solution for surface coating, then mixes with PAE and SBS resin, performs extrusion foaming treatment, forms a homogeneous system, and obtains a polyarylether composite foam material. The present invention uses SBS to coat the short carbon fiber, and with the help of the good compatibility of SBS and PAE, during the processing, the molecular chains can diffuse with each other to form a stable phase, which can indirectly enhance the interaction between the short carbon fiber and the PAE / SBS matrix, and adding less short carbon fiber can make the PAE composite foam material achieve better mechanical properties, and realize the continuous basic production of the polyarylether composite foam material; in addition, the short carbon fiber is not only used as a reinforcing filler in the present invention, but also can be used as a heterogeneous nucleating agent to optimize the pore structure during the foaming process. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The cross-sectional morphology SEM images of the polyarylether composite foam materials of Examples 1-4 and Comparative Example 1 are shown.

[0039] Figure 2 This is the SEM image of the polyarylene ether composite foam material of Example 3.

[0040] Figure 3 This is a graph showing the compressive strength of the polyarylether composite foam materials of Examples 1-4 and Comparative Example 1. DETAILED DESCRIPTION

[0041] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0042] Example 1

[0043] This embodiment provides a polyarylether composite foam material, the raw materials of which include the following components:

[0044] PAE resin: 10kg;

[0045] SBS resin: 10kg;

[0046] 245 antioxidant: 0.2kg;

[0047] Chopped carbon fiber: 0.4kg;

[0048] The preparation method of the polyarylether composite foam material comprises the following steps:

[0049] Step 1: 0.4 kg of chopped carbon fiber was immersed in 40 kg of SBS solution (solvent is toluene, solute content is 15 wt%) at 120 ° C for 10 min, and ultrasonically dispersed for 2 h, wherein the diameter of the chopped carbon fiber is 6 μm and the length is 3 mm; the chopped carbon fiber was taken out and dried in an oven for 24 h to obtain modified chopped carbon fiber;

[0050] Step 2: premixing the modified chopped carbon fiber with PAE and SBS resin in a high-speed stirrer at 200° C. for 10 minutes to obtain a mixture, wherein the mass fraction of the SBS resin is 50% based on the total mass of the PAE and SBS resins as 100%;

[0051] Step 3: adding the above mixture to a twin-screw extrusion foaming unit, injecting carbon dioxide into the barrel through a continuous gas injection pump, and performing extrusion foaming treatment to obtain a mixture, wherein the temperatures of various parts of the twin-screw extrusion foaming unit are set as follows: feeding section: 60°C, melting section: 220°C, gas dissolution section: 210°C, 210°C, 210°C, cooling section: 190°C, 170°C, 170°C, the head temperature is set to 180°C, and the speed of the twin-screw extrusion foaming unit is 80rad / min;

[0052] The mixture extruded from the die head is passed through a flattening machine, and the temperature of the flattening machine is set to 80°C to make its surface flat;

[0053] The traction device is used for cooling and shaping, wherein the traction speed is 1.5 m / min and the rotation speed of the fan on the bracket is fixed at 1050 rad / min, and finally the desired polyarylether composite foam material (denoted as PAE / 2% SCF) is obtained.

[0054] Example 2

[0055] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 1 only in that:

[0056] The raw materials contain the following components in quality:

[0057] PAE resin: 10kg;

[0058] SBS resin: 10kg;

[0059] 245 antioxidant: 0.2kg;

[0060] Chopped carbon fiber: 0.8kg;

[0061] The prepared polyarylether composite foam material (denoted as PAE / 4% SCF) was prepared.

[0062] Example 3

[0063] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 1 only in that:

[0064] The raw materials contain the following components in quality:

[0065] PAE resin: 10kg;

[0066] SBS resin: 10kg;

[0067] 245 antioxidant: 0.2kg;

[0068] Chopped carbon fiber: 1.2kg;

[0069] The prepared polyarylether composite foam material (denoted as PAE / 6% SCF) was prepared.

[0070] Example 4

[0071] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 1 only in that:

[0072] The raw materials contain the following components in quality:

[0073] PAE resin: 10kg;

[0074] SBS resin: 10kg;

[0075] 245 antioxidant: 0.2kg;

[0076] Chopped carbon fiber: 1.6kg;

[0077] The prepared polyarylether composite foam material (denoted as PAE / 8% SCF) was prepared.

[0078] Example 5

[0079] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 3 only in that:

[0080] In step 1, the length of the chopped carbon fibers used was 2 mm.

[0081] Example 6

[0082] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 3 only in that:

[0083] In step 1, the diameter of the chopped carbon fibers used was 4 mm.

[0084] Example 7

[0085] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 3 only in that:

[0086] In step 2, based on the total mass of PAE and SBS resins being 100%, the mass fraction of the SBS resin is 55%.

[0087] Example 8

[0088] This embodiment provides a polyarylether composite foam material and a preparation method thereof, which is different from Embodiment 3 only in that:

[0089] In step 1, the chopped carbon fibers were immersed in a SBS solution at 120° C. for 8 min.

[0090] Comparative Example 1

[0091] This comparative example provides a composite foam material, the raw materials of which include the following components by mass:

[0092] PAE resin: 10kg;

[0093] SBS resin: 10kg;

[0094] 245 antioxidant: 0.2kg;

[0095] Chopped carbon fiber: 0kg;

[0096] The preparation method of the composite foam material comprises the following steps:

[0097] PAE and SBS resins are added into a twin-screw extrusion foaming unit, and carbon dioxide is injected into the barrel through a continuous air injection pump to perform extrusion foaming treatment to obtain a mixture, wherein the temperatures of various parts of the twin-screw extrusion foaming unit are set to 60°C, 220°C, 210°C, 210°C, 210°C, 190°C, 170°C, 170°C, the head temperature is set to 180°C, and the speed of the twin-screw extrusion foaming unit is 80rad / min;

[0098] The mixture extruded from the die head is passed through a flattening machine, and the temperature of the flattening machine is set to 80°C to make its surface flat;

[0099] The traction equipment is used for cooling and shaping, wherein the traction speed is 1.5 m / min and the rotation speed of the fan on the bracket is fixed at 1050 rad / min, and finally the desired composite foam material (denoted as PAE / 0SCF) is obtained.

[0100] Comparative Example 2

[0101] This comparative example provides a polyarylether composite foam material, the raw materials of which include the following components by mass:

[0102] PAE resin: 10kg;

[0103] SBS resin: 10kg;

[0104] 245 antioxidant: 0.2kg;

[0105] Chopped carbon fiber: 1.2kg;

[0106] The preparation method of the polyarylether composite foam material comprises the following steps:

[0107] Step 1: Immerse the chopped carbon fiber in an SBS solution at 120° C. for 10 min and ultrasonically disperse it for 2 h, wherein the diameter of the chopped carbon fiber is 6 μm and the length is 6 mm; take out the chopped carbon fiber and dry it in an oven for 24 h to obtain modified chopped carbon fiber;

[0108] Step 2: premixing the modified chopped carbon fiber with PAE and SBS resin in a high-speed stirrer at 200° C. for 10 minutes to obtain a mixture, wherein the mass fraction of the SBS resin is 50% based on the total mass of the PAE and SBS resins as 100%;

[0109] Step 3: adding the above mixture into a twin-screw extrusion foaming unit for extrusion foaming treatment, injecting carbon dioxide into the barrel through a continuous air injection pump to obtain a mixture, wherein the temperatures of various parts of the twin-screw extrusion foaming unit are set to 60°C, 220°C, 210°C, 210°C, 210°C, 190°C, 170°C, 170°C, the head temperature is set to 180°C, and the speed of the twin-screw extrusion foaming unit is 80rad / min;

[0110] The mixture extruded from the die head is passed through a flattening machine, and the temperature of the flattening machine is set to 80°C to make its surface flat;

[0111] The cooling and shaping is carried out by a traction device, wherein the traction speed is 1.5 m / min, and the rotation speed of the fan on the bracket is fixed at 1050 rad / min, and finally the desired polyarylether composite foam material is obtained.

[0112] Comparative Example 3

[0113] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0114] In step 1, the diameter of the chopped carbon fibers used was 10 mm.

[0115] Comparative Example 4

[0116] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0117] The raw materials contain the following components in quality:

[0118] PAE resin: 10kg;

[0119] SBS resin: 10kg;

[0120] 245 antioxidant: 0.2kg;

[0121] Chopped carbon fiber: 2.0kg.

[0122] Comparative Example 5

[0123] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0124] In step 1, the chopped carbon fibers were immersed in SBS solution at 120° C. for 30 s.

[0125] Comparative Example 6

[0126] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0127] In step 1, the chopped carbon fibers were immersed in a SBS solution at 80° C. for 10 min.

[0128] Comparative Example 7

[0129] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0130] In step three, the temperatures of various parts of the twin-screw extrusion foaming unit are set to 60°C, 230°C, 230°C, 220°C, 220°C, 220°C, 200°C, and 200°C.

[0131] Comparative Example 8

[0132] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0133] In step three, the rotation speed of the twin-screw extrusion foaming unit is 60 rad / min.

[0134] Comparative Example 9

[0135] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0136] In step 2, based on the total mass of PAE and SBS resin being 100%, the mass fraction of the SBS resin is 20%.

[0137] Comparative Example 10

[0138] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0139] The chopped carbon fibers are pre-mixed with PAE and SBS resins directly without surface treatment.

[0140] Comparative Example 11

[0141] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 1 only in that:

[0142] The raw materials contain the following components in quality:

[0143] PAE resin: 10kg;

[0144] SBS resin: 10kg;

[0145] 245 antioxidant: 0.2kg;

[0146] GO graphene oxide: 0.4kg.

[0147] Comparative Example 12

[0148] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 1 only in that:

[0149] The raw materials contain the following components in quality:

[0150] PAE resin: 10kg;

[0151] SBS resin: 10kg;

[0152] 245 antioxidant: 0.2kg;

[0153] Nano silicon dioxide: 0.4kg.

[0154] Comparative Example 13

[0155] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 1 only in that:

[0156] The raw materials contain the following components in quality:

[0157] PAE resin: 10kg;

[0158] SBS resin: 10kg;

[0159] 245 antioxidant: 0.2kg;

[0160] Nano calcium carbonate: 0.4kg.

[0161] Comparative Example 14

[0162] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 1 only in that:

[0163] The raw materials contain the following components in quality:

[0164] PAE resin: 10kg;

[0165] SBS resin: 10kg;

[0166] 245 antioxidant: 0.2kg;

[0167] CNF carbon nanofiber: 0.4kg.

[0168] Comparative Example 15

[0169] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 1 only in that:

[0170] The raw materials contain the following components in quality:

[0171] PAE resin: 10kg;

[0172] SBS resin: 10kg;

[0173] 245 antioxidant: 0.2kg;

[0174] MXene nanofibers: 0.4 kg.

[0175] Comparative Example 16

[0176] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0177] In step 1, the chopped carbon fibers were immersed in a SBS solution at 200° C. for 10 min.

[0178] Comparative Example 17

[0179] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0180] In step three, the temperatures of various parts of the twin-screw extrusion foaming unit are set to 60°C, 180°C, 180°C, 160°C, 160°C, 160°C, 150°C, and 150°C.

[0181] Comparative Example 18

[0182] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0183] In step 2, pre-mixing is performed at 230° C. for 10 minutes to obtain a mixture.

[0184] Comparative Example 19

[0185] This comparative example provides a polyarylether composite foam material and a preparation method thereof, which differs from Example 3 only in that:

[0186] In step 2, pre-mixing is performed at 170° C. for 10 minutes to obtain a mixture.

[0187] The test results of the above embodiments and comparative examples are shown in Table 1.

[0188] Table 1

[0189]

[0190]

[0191] It can be seen from Table 1 that the polyarylether composite foam materials prepared in Examples 1-8 have a closed cell rate of ≥80% and a compression strength of ≥1.9 MPa, and have good mechanical properties and stability.

[0192] In Comparative Example 1, no chopped carbon fibers are added, but PAE and SBS resins are directly added to a twin-screw extrusion foaming unit for extrusion foaming treatment. Compared with Example 1, the closed porosity and compressive strength of the composite foam material of Comparative Example 1 are reduced, and the average pore size is increased, which indicates that after the surface treatment of the chopped carbon fibers, the SBS molecular chains on the chopped carbon fibers will diffuse with the PAE molecular chains during the processing to form a stable phase, indirectly enhancing the interaction between the chopped carbon fibers and the PAE / SBS matrix, and improving the interfacial bonding force, thereby significantly improving the mechanical properties and thermal stability of the foam material.

[0193] The length of the chopped carbon fiber used in Comparative Example 2 is 6 mm. Since the length of the chopped carbon fiber is too long, the nucleation effect is too strong, and the pores are easily merged, thereby reducing the closed cell ratio and the compression strength.

[0194] The diameter of the chopped carbon fiber used in Comparative Example 3 is 10 mm. Due to the large diameter of the chopped carbon fiber, defect points are easily formed during the compression process, which destroys the pore structure and reduces the compression strength of the overall foam product.

[0195] Comparative Example 4 adds 10% of chopped carbon fibers, which exceeds the amount of chopped carbon fibers added in the present invention, resulting in an uneven structure of the foam material. The high nucleation efficiency may lead to the merging and rupture of the bubbles, resulting in a decrease in the closed cell rate. In addition, in terms of processing, the more chopped carbon fibers are added, the more difficult the processing becomes, resulting in difficulty in molding the polyarylether composite foam material.

[0196] The immersion time of Comparative Example 5 is 30 seconds. Since the immersion time is too short, the SBS in the immersion liquid cannot completely cover the chopped carbon fibers, resulting in a poor volume expansion effect.

[0197] In Comparative Example 6, the impregnation temperature is too low, 80° C., so that the SBS in the impregnation solution cannot be completely melted, and the portion in contact with the chopped carbon fibers is small, resulting in a poor volume expansion effect.

[0198] The overall system temperature of the twin-screw extrusion foaming unit in Comparative Example 7 is too high, resulting in too high a melt temperature. The melt strength of PAE is low at high temperatures, and therefore, a complete foam material cannot be produced.

[0199] The speed of the twin-screw extrusion foaming unit in Comparative Example 8 is too low, the PAE melt viscosity itself is large and the flow is not smooth. The low screw speed causes the system pressure of the entire extrusion foaming unit to be extremely high, the expansion power at the exit mold is large, and the bubble growth power is too strong, resulting in rupture, resulting in a low foam closed cell rate.

[0200] The mass fraction of the SBS resin in Comparative Example 9 is too low, resulting in excessive matrix viscosity and the product cannot be formed.

[0201] In comparative example 10, the chopped carbon fibers are directly premixed with PAE and SBS resin without surface treatment; while in example 3, SBS is first used to coat the chopped carbon fibers, and the SBS molecular chains on the chopped carbon fibers diffuse with the PAE molecular chains during processing, thereby establishing a strong interaction between the chopped carbon fibers and PAE, improving the interface bonding force and the mechanical properties. This shows that the untreated chopped carbon fibers cannot establish an effective connection with PAE, and therefore have poor mechanical properties.

[0202] After the inorganic fillers used in Comparative Examples 11-15 are added as reinforcing phases, the performance improvement of the composite materials is also limited, and there is no interaction (hydrogen bonding / ionic bonding / covalent bonding) between the fillers and the matrix, resulting in poor compatibility between SBS and PAE.

[0203] In Comparative Example 16, the time and temperature of immersing the chopped carbon fibers in the SBS solution are too high. Since the SBS has low viscosity and strong fluidity, it is not easy to coat the surface of the chopped carbon fibers, thereby affecting the modification effect of the chopped carbon fibers.

[0204] The overall system temperature of the twin-screw extrusion foaming unit of Comparative Example 17 is too low, and the melt viscosity is too large, so it is impossible to produce a sheet with a foaming ratio of five times, and the material can hardly be foamed.

[0205] In Comparative Example 18, the premixing was carried out at 230° C. for 10 minutes. Since the premixing temperature was too high, the thermal stability of the SBS molecular chain was poor and it was degraded to varying degrees before being mixed with the PAE molecular chain, thus affecting the performance of the final foam material.

[0206] In Comparative Example 19, premixing was performed at 170° C. for 10 minutes. Since the premixing temperature was too low, the glass transition temperature of the PAE molecular chain could not be reached, and the movement of the molecular chain was difficult, resulting in the inability of PAE and SBS to form a stable phase.

[0207] Figure 1 The cross-sectional morphology SEM images of the polyarylether composite foam materials of Examples 1-4 and Comparative Example 1 with different addition amounts of chopped carbon fibers. Figure 1 It can be seen that the surface pretreated chopped carbon fibers in Examples 1-4 are well bonded to the PAE / SBS matrix, and large pieces of PAE resin are wrapped around the chopped carbon fibers. This indicates that the interface between the chopped carbon fibers and PAE is well bonded, and the bonding effect is significant, making it more difficult to extract the carbon fibers, significantly improving the mechanical properties of the composite material, and laying the foundation for the preparation of high compressive PAE composite foam materials.

[0208] Figure 2 The SEM image of the chopped carbon fiber distributed in the polyarylether composite foam material in Example 3 is shown in FIG. Figure 2It can be clearly observed from Figures (a) and (b) that the chopped carbon fibers are interspersed in the PAE / SBS matrix. After low-temperature quenching and external force stretching, some pore structures are distributed on the chopped carbon fibers, which indirectly proves that the modified chopped carbon fibers have good compatibility with PAE. Figure 2 Figures (c) and (d) in the figure show electron microscope images of chopped carbon fibers interspersed in PAE composite foam at different magnifications, where it can be seen that the pores around the chopped carbon fibers are smaller, and under the constraint of the chopped carbon fibers, the pore structure is partially oriented. This shows that the addition of chopped carbon fibers increases the melt strength of PAE, restricts the diffusion of gas in all directions, forms small pores around the chopped carbon fibers, and then forms a uniform pore structure.

[0209] Figure 3 The compressive strength diagram of the polyarylether composite foam material of Examples 1-4 and Comparative Example 1 is shown in FIG. Figure 3 It can be seen that as the content of chopped carbon fiber increases from 0 to 6 parts, the compressive strength of the composite foam increases from 0.8 MPa to 2.5 MPa, an increase of 212.5%. When the content of chopped carbon fiber continues to increase, the compressive strength no longer increases. This is because some of the cells merge and the cell size becomes larger, thereby reducing the compressive strength.

Claims

1. A method for preparing a polyarylether composite foam material, wherein: The following steps are involved: Step 1: immersing the chopped carbon fiber in an SBS solution for surface coating to obtain modified chopped carbon fiber; wherein the immersion temperature is 100-150° C. and the immersion time is 1-10 min; Step 2: premixing the modified chopped carbon fiber with PAE and SBS resin to obtain a mixture; Step 3: Extruding and foaming the mixture, and then flattening and pulling the mixture to obtain a polyarylether composite foam material; Wherein, based on the total mass of PAE and SBS resin being 100%, the addition amount of the chopped carbon fiber is 1%-8%.

2. The method for preparing a polyarylether composite foam material according to claim 1, wherein: In step 1, the mass ratio of the chopped carbon fiber to the SBS in the SBS solution is 1:(3-20); And / or, the diameter of the chopped carbon fiber is ≤7 μm, and the length of the chopped carbon fiber is ≤3 mm; Preferably, the diameter of the chopped carbon fibers is ≤4 μm, and the length of the chopped carbon fibers is ≤2 mm.

3. The method for preparing the polyarylether composite foam material according to claim 1, wherein: In step 2, based on the total mass of PAE and SBS resins being 100%, the mass fraction of the SBS resin is 40%-60%.

4. The method for preparing a polyarylether composite foam material according to claim 1, wherein: In step 2, the temperature at which the modified chopped carbon fiber is premixed with the PAE and SBS resins is 190-210° C.; And / or, the modified chopped carbon fiber is pre-mixed with the PAE and SBS resins for 5-10 minutes.

5. The method for preparing the polyarylether composite foam material according to claim 1, wherein: In step 3, the feeding temperature of the mixture for extrusion foaming treatment is 60-80°C, and the blending temperature for extrusion foaming treatment is 160-220°C; Preferably, the temperatures of various parts of the mixture subjected to extrusion foaming treatment are set to 60-80°C, 200-220°C, 190-210°C, 190-210°C, 190-210°C, 180-200°C, 160-190°C, 160-190°C.

6. The method for preparing a polyarylether composite foam material according to claim 1, wherein: In step three, the mixture is subjected to extrusion foaming treatment using a twin-screw extrusion foaming unit with a rotation speed of 80-120 rad / min, preferably 80-100 rad / min.

7. The method for preparing a polyarylether composite foam material according to claim 1, wherein: In step three, the temperature of the flattening treatment is 60-100°C.

8. The method for preparing a polyarylether composite foam material according to claim 1, wherein: In step 3, the pulling speed of the pulling process is 1-2 m / min; And / or, the rotation speed of the traction treatment is 900-2000 rad / min.

9. A polyarylene ether composite foam material obtained by the method for preparing a polyarylene ether composite foam material according to any one of claims 1 to 8.

10. The polyarylether composite foam material according to claim 9, wherein The polyarylether composite foam material satisfies one or a combination of two or more of the following conditions: The average cell size of the polyarylether composite foam material is 300-400 μm; The closed cell rate of the polyarylether composite foam material is 80%-83%; The compressive strength of the polyarylether composite foam material is 1.9-2.5 MPa.

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