Waste carpet recycled PA hollow glass bead composite material and preparation method thereof

Abstract

The invention discloses a waste carpet recycled PA hollow glass bead composite material and a preparation method thereof. The composite material comprises the following components in parts by weight: 60-80 parts of waste carpet recycled PA; 20 to 40 parts of hollow glass beads; 3 to 8 parts of a PCL / PEG temperature-sensitive auxiliary bag; 0.5 to 2 parts of PEEK (Polyether Ether Ketone) micro powder; 0.1 to 0.8 part of polyamide wax; 0.05 to 0.2 part of a coupling agent; 0.05 to 0.2 part of a scavenging agent; and 0.1 to 0.5 part of an antioxidant. According to the invention, the dynamic buffer characteristic of the temperature-sensitive coating system, and the impurity targeting treatment and viscosity self-adaption function of the auxiliary system are cooperated, so that stable dispersion and crushing resistance of the microbeads in a wide temperature range and multi-impurity environment of regenerated PA processing are realized. The engineering application requirements of automobile interiors, household appliance shells, intelligent wearable devices and the like are met, the high-value utilization level of carpet recycling PA is remarkably improved, meanwhile, the production process is simplified, energy consumption is reduced, and the green circulation development policy is met.

Description

Technical Field

[0001] This invention belongs to the field of polyamide composite material technology, specifically relating to a composite material of PA hollow glass microspheres recycled from waste carpets. It is particularly suitable for engineered products such as automotive interiors, home appliance shells, and smart wearable device shells that require lightweight, impact resistance, and dimensional stability, and can realize the high-value utilization of PA recycled from waste carpets. Background Technology

[0002] The recycling of PA from waste carpets faces dual technical challenges during processing due to the dispersed sources (mixed recycling of household and commercial carpets): "complex impurities + drastic viscosity fluctuations". This results in a breakage rate of hollow glass microspheres that is more than 10% higher than that of virgin materials during composite processing, severely limiting the high-value utilization of recycled PA and the large-scale application of hollow glass microspheres.

[0003] Firstly, the impurities are clearly defined and pose significant hazards: Calcium carbonate (a rigid inorganic impurity with a hardness ≥3) contained in recycled PA from waste carpets forms a "hard particle-microbead" collision system during melt processing, easily causing scratches on the surface of the microbeads and leading to breakage; PP (a non-polar polymer with extremely poor compatibility with PA) easily agglomerates, forming localized stress concentration zones that compress the microbeads, causing them to break; adhesives (mainly polyurethane and acrylate) partially decompose at high temperatures, producing sticky substances that easily encapsulate the microbeads, forming aggregates and exacerbating shear breakage; trace amounts of oily additives (mineral oil, antistatic agent residues, etc.) reduce the interfacial bonding force between the microbeads and the PA matrix, causing uneven stress on the microbeads during melt flow, leading to breakage.

[0004] Secondly, the viscosity fluctuates significantly: After long-term use, the PA fibers from recycled carpets undergo oxidative aging, resulting in molecular chain breakage and the formation of short chain fragments. These fragments, mixed with residual additives and different batches of recycled materials, cause the viscosity of the recycled PA melt to fluctuate by ±35% (far exceeding the ±20% of recycled PP). Although this can be partially improved by adding a homogenization process, the differences in local shear stress during processing remain significant, further exacerbating the crushing and breakage of microspheres.

[0005] Existing technologies have significant limitations: Chinese patent CN118879100A discloses a polyurethane elastic coating of hollow glass microspheres, which requires pre-coating the microspheres using a solution method, resulting in a complex process, solvent residue, and high industrialization costs. Furthermore, polyurethane is prone to decomposition and failure at the high temperatures (230-280℃) during PA6 processing. Chinese patent CN113930068B uses a single-screw extrusion process to reduce shear force, but its production efficiency is low. Conventional in-situ coating technologies are mostly single-component coatings, failing to balance the microspheres' anti-breakage performance with matrix compatibility. They also lack targeted treatment mechanisms for complex impurities in recycled PA and do not address the breakage issues caused by PP impurity agglomeration and viscosity fluctuations. In addition, existing technologies generally employ a two-step method of "pre-coating microspheres + subsequent mixing and extrusion," which suffers from long processes, high energy consumption, and easy coating layer detachment, making it difficult to meet the demands of continuous production. Therefore, there is an urgent need to develop an integrated technology that combines "in-situ coating in the extruder + targeted impurity treatment + dynamic viscosity adaptation" to simplify the production process, solve the problem of microsphere breakage, and fill the technological gap in the composite of carpet recycled PA and hollow glass microspheres. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, this invention provides a composite material of recycled PA hollow glass microspheres from waste carpets. Through component synergistic design and process innovation, it achieves low breakage rate of microspheres and high performance of composite materials in the complex processing environment of recycled PA.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A composite material of recycled PA hollow glass microspheres from waste carpets comprises the following components in parts by weight:

[0009] Waste carpet recycling and regeneration PA: 60-80 parts;

[0010] Hollow glass microspheres: 20-40 parts;

[0011] PCL / PEG temperature-sensitive additive package: 3-8 parts;

[0012] PEEK micro powder: 0.5-2 parts;

[0013] Polyamide wax: 0.1-0.8 parts;

[0014] Coupling agent: 0.05-0.2 parts;

[0015] Cleaning agent: 0.05-0.2 parts;

[0016] Antioxidant: 0.1-0.5 parts.

[0017] The recycled PA from the waste carpet is recycled PA6 or recycled PA66; the impurity content of the recycled PA meets the following requirements: calcium carbonate ≤ 4%, PP ≤ 7%, and adhesive ≤ 3%.

[0018] The hollow glass microspheres described herein have a compressive strength ≥10000 psi and a density of 0.3-0.7 g / cm³. 3 The D50 particle size is 10-50μm, and the sphericity is ≥0.95.

[0019] The PCL / PEG temperature-sensitive additive package is composed of the following components by weight percentage: PCL 60-80%, PEG 20-40%, silane coupling agent KH-5603-5%, and antioxidant 10100.5-1%; wherein the number average molecular weight of PEG is 2000-4000, the number average molecular weight of PCL is 8000-11000, the crystallinity is 60-70% at room temperature, and the crystallinity decreases to 8-15% at a processing temperature of 230-280℃.

[0020] The PEEK micro powder is polyetheretherketone micro powder with a particle size of 2-5 μm and a glass transition temperature of 143℃. It has typical shear thinning characteristics and can be adapted to the viscosity fluctuation adjustment requirements of regenerated PA melt.

[0021] The polyamide wax has a particle size of 1-3μm and a melting point of 100-110℃. It can work synergistically with PEEK micropowder to achieve viscosity self-adaptation and improve the compatibility between PP and PA matrix.

[0022] The coupling agent contains phosphate ester groups, preferably titanate coupling agent TMC-201, which can chemically react with the hydroxyl groups on the surface of calcium carbonate to form an organic coating layer, changing the polarity of the calcium carbonate surface from hydrophilic to lipophilic, thereby reducing its impact damage to hollow glass microspheres.

[0023] The cleaning agent is preferably polyglycerol ricinoleate (PGPR, HLB value 3-4), which has emulsifying and dispersing effects. It can decompose the polyurethane / acrylate macromolecular chains in the adhesive and disperse them into tiny particles of 5-10 μm. At the same time, it emulsifies trace amounts of oil, prevents oil from accumulating on the surface of the microbeads, and improves the interfacial bonding between the microbeads and the PA matrix.

[0024] The antioxidant is a compound system of antioxidant 168 and antioxidant 1010, with a compound mass ratio of 1:1.

[0025] The method for preparing the above-mentioned recycled PA hollow glass microsphere composite material from waste carpet is characterized by comprising the following steps:

[0026] A twin-screw extruder with a length-to-diameter ratio (L / D) of 40–44 is used, equipped with a main feed port, a front feed port, and a rear feed port. The specific operation is as follows:

[0027] (1) PEEK micro powder, polyamide wax, coupling agent, antioxidant, and scavenger are mixed with the dried regenerated PA according to the ratio, and put into a high-speed mixer. Stir at 80°C for 5 minutes and at a speed of 800 r / min to obtain the main material mixture, which is then fed into the main feed port.

[0028] (5) Insert the PCL / PEG temperature-sensitive additive package into the front feed port (at a distance of 1 / 3 to 1 / 2 of the screw length from the die head);

[0029] (6) Insert the hollow glass microspheres into the rear side feed port (located 1 to 2 heating blocks after the front side feed port);

[0030] (7) The temperature of the twin-screw extruder is set to 230-290℃; the screw speed is automatically adjusted by the current feedback of the extruder (the speed is increased when the viscosity is high and the current is high, and the speed is decreased when the viscosity is low and the current is low); the vacuum degree is controlled at -0.08 to -0.09MPa; the composite material of PA hollow glass microspheres from waste carpet is obtained by pelletizing (pelletizing temperature 60-80℃).

[0031] The principle of this invention is as follows:

[0032] 1) PCL / PEG temperature-sensitive additive dynamic buffer coating system: Under the shearing and diffusion action in the extruder, due to the reaction priority of the hydroxyl groups on the surface of the microspheres and KH-560 and the difference in compatibility of PCL / PEG, a gradient coating layer is naturally formed: the inner layer (close to the microspheres) utilizes the flexible buffering property of PCL, which reduces its crystallinity to 8-15% at a processing temperature of 230-280℃, to resist the collision and shear stress of calcium carbonate; the outer layer (close to the PA matrix) uses PEG to improve the flexibility of the coating layer and its compatibility with the PA matrix; the silane coupling agent KH-560 forms chemical bonds with the hydroxyl groups on the surface of the microspheres and the PCL / PEG molecular chains at high temperatures, improving the adhesion of the coating layer.

[0033] 2) Viscosity-Adaptive Composite Additive System: PEEK micropowder and polyamide wax synergistically adapt to the wide viscosity fluctuations of the recycled PA matrix. When the viscosity of the recycled material is high, the PEEK micropowder can reduce the friction within the melt and improve flow efficiency. When the viscosity of the recycled material is low, its micropowder particles can increase the structural support of the melt and prevent excessive flow. The shear-thinning properties of PEEK stabilize the melt viscosity at 800-1500 Pa·s, providing a stable environment for in-situ coating.

[0034] 3) Targeted Impurity Compatibility Auxiliary System: A "precise targeted treatment" mechanism is constructed to address the complex impurities in recycled PA from waste carpets. Titanate coupling agents modify the surface polarity of calcium carbonate, reducing its direct collision with microspheres; PGPR removers emulsify and disperse adhesives and oil stains, preventing agglomerate formation; polyamide wax improves the compatibility between PP and PA matrices, eliminating localized stress concentrations, forming a dual protection of "impurity treatment - in-situ coating".

[0035] 4) Integrated process of "dual-side feeding + in-situ coating within the extruder": This simplifies the process by eliminating the need for pre-coating microspheres. The main feed consists of a mixture of recycled PA and additives, achieving impurity pretreatment and initial viscosity adjustment of the matrix. The front-side feed injects the coating system, preparing for microsphere coating. The rear-side feed adds microspheres, achieving gradient coating and uniform dispersion under mild shear conditions. The screw speed is automatically adjusted via extruder current feedback to precisely adapt to viscosity fluctuations. The precise matching of the side feed position and rate ensures effective coating and processing stability.

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

[0037] 1) Significantly reduced breakage rate of microspheres: Through the triple synergy of "temperature-sensitive coating + targeted impurity treatment + viscosity self-adaptation", the breakage rate of hollow glass microspheres is ≤15%, which is more than 50% lower than the existing technology, achieving a perfect balance between lightweight and low breakage rate.

[0038] 2) Excellent composite material properties: tensile strength ≥60MPa, flexural modulus ≥2800MPa, notched impact strength ≥4.0KJ / m 2 Its various mechanical properties meet the requirements of engineering applications such as automotive interiors and home appliance housings, solving the pain point of insufficient performance of recycled PA composite materials.

[0039] 3) Green and efficient process: The integrated in-situ coating process eliminates the need for pre-coating and solvent treatment, simplifies the production process, reduces energy consumption, leaves no solvent residue, and improves the high-value utilization of recycled PA, which is in line with the national green and circular development policy.

[0040] 4) Strong compatibility with impurities and viscosity: It specifically solves the problem of complex impurities such as calcium carbonate, PP, and adhesives in recycled PA and the problem of viscosity fluctuations within a wide range of ±35%. The current during processing is stable at 60%-80% of the rated current, with no frequent alarms, and high production continuity and stability.

[0041] 5) Wide range of applications: Low product density (0.78-1.03 g / cm³) 3 It combines lightweight and high rigidity, and can meet the material needs of multiple fields such as automobiles, home appliances, and smart wearables, with broad market application prospects. Detailed Implementation

[0042] To make the technical solution of the present invention clearer and more explicit, the present invention will be further described below. Any solution derived by equivalent substitution and conventional reasoning of the technical features of the present invention falls within the protection scope of the present invention.

[0043] The embodiments of the present invention use the following materials:

[0044] PA6 recycled from waste carpet: PRET Advanced Materials LLC; density 1.16 g / cm³ 3 Tensile strength 65 MPa, notched impact strength 4.5 KJ / m 2 Flexural strength 90MPa, flexural modulus 2500MPa, containing 2% calcium carbonate, 7% PP, and 2% adhesive;

[0045] PA66 recycled from waste carpet: PRET Advanced Materials LLC; density 1.15 g / cm³ 3 Tensile strength 68 MPa, notched impact strength 3.7 KJ / m 2 Flexural strength 97MPa, flexural modulus 2700MPa, containing 3% calcium carbonate, 6% PA6, 5% PP, and 3% adhesive;

[0046] Hollow glass microspheres A: 3M S60HS, compressive strength 18000psi, particle size 30μm, density 0.60g / cm³ 3 ;

[0047] Hollow glass microspheres B: 3M iM16K, compressive strength 16000 psi, particle size 20 μm, density 0.46 g / cm³ 3 ;

[0048] PCL / PEG temperature-sensitive additive package: self-made. 70% PCL (Corbion PC17, Netherlands), 24% PEG (PEG-3000), 5% silane coupling agent KH-560, and 10101% antioxidant were added to a high-speed mixer in proportion and stirred at 80°C for 5 minutes at a speed of 800 r / min to obtain a solid powder additive package.

[0049] Other additives: PEEK micro powder (particle size 2-5μm), polyamide wax (particle size 1-3μm), titanate coupling agent TMC-201, polyglycerol ricinoleate PGPR (HLB value 3-4), antioxidant 1010, antioxidant 168, all of which are industrial grade.

[0050] Example 1

[0051] Weigh out 1 part of PEEK micro powder, 0.4 parts of polyamide wax, 0.1 parts of coupling agent, 0.1 parts of cleaning agent, 0.3 parts of antioxidant, and 1 part of dried waste carpet recycled PA663. Add them to a high-speed mixer, stir at 80°C for 5 minutes at a speed of 800 r / min to obtain the main material mixture, and feed it into the main feed port (Zone 1).

[0052] Weigh out 5 portions of the PCL / PEG temperature-sensitive additive package and add them through the front feeding port (Zone 6);

[0053] Weigh 30 parts of hollow glass microspheres A and feed them into the rear side feed port (Zone 7); the twin-screw extruder temperature is 230-270℃; the output rate is set to 300KG / h, and the screw speed is automatically adjusted based on the extruder current (60%~80% of the rated current). The vacuum degree is controlled at -0.08~-0.09MPa; granulation is performed using an underwater pelletizer (pelletizing temperature 60-80℃) to obtain a PA hollow glass microsphere composite material from recycled waste carpet.

[0054] Example 2

[0055] The difference from Example 1 is: 1.5 parts PEEK micro powder, 0.8 parts polyamide wax, 8 parts PCL / PEG temperature-sensitive additive package, and 9.2 parts recycled PA65 from waste carpet.

[0056] Example 3

[0057] The difference from Example 1 is: 1.5 parts PEEK micro powder, 0.5 parts polyamide wax, 8 parts PCL / PEG temperature-sensitive additive package, 40 parts hollow glass microspheres A, and 49.5 parts recycled PA6 from waste carpet.

[0058] Example 4

[0059] The difference from Example 1 is: 2 parts PEEK micro powder, 0.8 parts polyamide wax, 8 parts PCL / PEG temperature-sensitive additive package, 40 parts hollow glass microspheres B, and 48.7 parts recycled PA6 from waste carpet.

[0060] Example 5

[0061] The difference from Example 1 is: 0.8 parts PEEK micro powder, 0.3 parts polyamide wax, 0.2 parts coupling agent, 0.4 parts antioxidant, 3 parts PCL / PEG temperature-sensitive additive package, 20 parts hollow glass microspheres A, and 5.2 parts recycled PA67 from waste carpet.

[0062] Example 6

[0063] The difference from Example 1 is as follows: 1.6 parts PEEK micro powder, 0.3 parts polyamide wax, 0.1 parts coupling agent, 0.2 parts cleaning agent, 0.4 parts antioxidant, 4 parts PCL / PEG temperature-sensitive additive package, 20 parts hollow glass microspheres A, and 3.4 parts recycled PA667 from waste carpet. The twin-screw extruder temperature is 250-290℃.

[0064] Comparative Example 1

[0065] The difference from Example 1 is that the PCL / PEG temperature-sensitive additive package is not included, and the PA6 content of the recycled waste carpet is increased accordingly.

[0066] Comparative Example 2

[0067] The difference from Example 1 is that: 0.6 parts of PEEK micro powder, 2 parts of PCL / PEG temperature-sensitive additive package, and the PA6 content of recycled waste carpet is increased accordingly.

[0068] Comparative Example 3

[0069] The difference from Example 1 is that PEEK micro powder and polyamide wax are not used, and the PA6 content of recycled waste carpet is increased accordingly. During production, frequent alarms occurred due to current fluctuations exceeding the 60%–80% set range, making automatic programming impossible. Therefore, a constant speed of 350 r / min was adopted for production.

[0070] Comparative Example 4

[0071] The difference from Example 1 is that there is no polyamide wax, coupling agent, or cleaning agent, and the PA6 content of recycled waste carpet is increased accordingly.

[0072] Comparative Example 5

[0073] The difference from Example 5 is that: 5 parts of PEEK micro powder, 10 parts of PCL / PEG temperature-sensitive additive package, and the PA6 content of recycled waste carpet is reduced accordingly.

[0074] Comparative Example 6

[0075] The difference from Example 5 is that the PCL / PEG temperature-sensitive additive package is fed in from the main feed port.

[0076] Comparative Example 7

[0077] The difference from Example 6 is that there is no coupling agent or cleaning agent, and the PA66 content of recycled waste carpet is increased accordingly.

[0078] Comparative Example 8

[0079] The difference from Example 4 is that the screw speed is increased to 600 r / min.

[0080] Product performance testing methods:

[0081] Density: Tested according to ISO 1183-1 standard, sample size 80×10×4mm;

[0082] Microsphere breakage rate: The density of microspheres before extrusion and the density of composite material after ignition ash were tested using a true density meter and calculated according to the formula "breakage rate (%) = 100% × [2.3 × (post density - pre density)] / [post density × (2.3 - pre density)]".

[0083] Tensile strength: tested according to ISO 527 standard;

[0084] Flexural modulus: tested according to ISO 527 standard;

[0085] Notched impact strength: tested according to ISO 180 standard, with a sample size of 80×10×4mm;

[0086] Table 1. Distribution ratios (parts by weight) and performance test results of each group in the embodiments.

[0087]

[0088]

[0089] Table 2 shows the distribution ratios (parts by weight) and performance test results for each group in the comparative examples.

[0090]

[0091] The breakage rate of microspheres in Examples 1-6 was ≤15%, which was more than 50% lower than that in the comparative example. This fully demonstrates that the synergistic effect of the "temperature-sensitive coating system + targeted additive system + viscosity adaptive system" is significant and can effectively solve the problem of microsphere breakage in the complex environment of regenerated PA.

[0092] The absence of any core component (e.g., Comparative Example 1 lacks a temperature-sensitive additive package, Comparative Example 3 lacks a viscosity-adaptive additive, and Comparative Example 4 lacks a targeted impurity treatment additive) or deviation from process parameters (e.g., Comparative Example 6 changes the feeding position, and Comparative Example 8 has an excessively high rotation speed) all resulted in a surge in breakage rate and a decrease in mechanical properties, demonstrating the indispensability of each component and process parameter in this application.

[0093] Examples 2 and 3, due to the optimized component ratio (moderate amount of microbeads, balanced ratio of temperature-sensitive additive package and viscosity-adaptive additive), have the best overall performance, with a breakage rate ≤10% and tensile strength ≥70MPa, demonstrating the optimization potential of the technology in this application.

[0094] In Comparative Example 5, the excessive addition of PEEK micro powder and temperature-sensitive additive package led to a decrease in the mechanical properties of the material; in Comparative Example 2, the insufficient amount of core additive resulted in an unsatisfactory breakage rate, demonstrating the rationality and optimization of the component dosage range in this application.

Claims

1. A composite material of PA hollow glass microspheres recycled from waste carpet, characterized in that, The components include the following parts by weight: Waste carpet recycling and regeneration PA: 60-80 parts; Hollow glass microspheres: 20-40 parts; PCL / PEG temperature-sensitive additive package: 3-8 parts; PEEK micro powder: 0.5-2 parts; Polyamide wax: 0.1-0.8 parts; Coupling agent: 0.05-0.2 parts; Cleaning agent: 0.05-0.2 parts; Antioxidant: 0.1-0.5 parts.

2. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The recycled PA from the waste carpet is recycled PA6 or recycled PA66; the impurity content of the recycled PA meets the following requirements: calcium carbonate ≤ 4%, PP ≤ 7%, and adhesive ≤ 3%.

3. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The compressive strength of the hollow glass microspheres is ≥ 10000psi, density 0.3-0.7g / cm³ 3 The D50 particle size is 10-50μm, and the sphericity is ≥0.

95.

4. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The PCL / PEG temperature-sensitive additive package is composed of the following components by weight percentage: PCL 60-80%, PEG 20-40%, silane coupling agent KH-5603-5%, and antioxidant 10100.5-1%; wherein the number average molecular weight of PEG is 2000-4000, the number average molecular weight of PCL is 8000-11000, the crystallinity is 60-70% at room temperature, and the crystallinity decreases to 8-15% at a processing temperature of 230-280℃.

5. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The PEEK micro powder is polyetheretherketone micro powder with a particle size of 2-5 μm and a glass transition temperature of 143℃. It has typical shear thinning characteristics and can be adapted to the viscosity fluctuation adjustment requirements of regenerated PA melt.

6. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The polyamide wax has a particle size of 1-3μm and a melting point of 100-110℃. It can work synergistically with PEEK micropowder to achieve viscosity self-adaptation and improve the compatibility between PP and PA matrix.

7. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The coupling agent is TMC-201, which contains phosphate ester groups or titanate esters. It reacts chemically with the hydroxyl groups on the surface of calcium carbonate to form an organic coating layer, changing the polarity of the calcium carbonate surface from hydrophilic to lipophilic, thereby reducing its impact damage to hollow glass microspheres.

8. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The cleaning agent is polyglycerol ricinoleate, which has emulsifying and dispersing effects. It can decompose the polyurethane / acrylate macromolecular chains in the adhesive and disperse them into tiny particles of 5-10 μm. At the same time, it emulsifies trace amounts of oil, prevents oil from accumulating on the surface of the microbeads, and improves the interfacial bonding between the microbeads and the PA matrix.

9. The PA hollow glass microsphere composite material for recycling waste carpets according to claim 1, characterized in that: The antioxidant is a compound system of antioxidant 168 and antioxidant 1010, with a compound mass ratio of 1:

1.

10. A method for preparing the PA hollow glass microsphere composite material from recycled waste carpet as described in any one of claims 1-9, characterized in that, Includes the following steps: A twin-screw extruder with a length-to-diameter ratio (L / D) of 40–44 is used, equipped with a main feed port, a front feed port, and a rear feed port. The specific operation is as follows: (1) PEEK micro powder, polyamide wax, coupling agent, antioxidant, and scavenger are mixed with the dried regenerated PA according to the ratio, and put into a high-speed mixer. Stir at 80°C for 5 minutes and at a speed of 800 r / min to obtain the main material mixture, which is then fed into the main feed port. (2) Put the PCL / PEG temperature-sensitive additive package into the front feed port, at a distance of 1 / 3 to 1 / 2 of the screw length from the die head; (3) The hollow glass microspheres are fed into the rear side feed port, located 1 to 2 heating blocks after the front side feed port; (4) The temperature of the twin-screw extruder is set to 230-290℃; the screw speed is automatically adjusted by the current feedback of the extruder. When the viscosity is high and the current is high, the speed is increased, and when the viscosity is low and the current is low, the speed is decreased; the vacuum degree is controlled at -0.08 to -0.09MPa; the material is granulated by a pelletizer at a pelletizing temperature of 60-80℃; and the recycled PA hollow glass microsphere composite material is obtained.

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