Thermoplastic polyester elastomer composite, method of making and automotive engine intake manifold

Abstract

The application relates to the technical field of high polymer materials, and particularly discloses a thermoplastic polyester elastomer composite material, a preparation method thereof and an automobile engine air inlet pipe, wherein the thermoplastic polyester elastomer composite material is prepared from the following components in parts by weight: 100 parts of thermoplastic polyester elastomer resin TPEE, 0.5-1.2 parts of a chain extender, 0.05-0.2 parts of a composite catalyst and 4-10 parts of nano acid-removing master batch. The nano acid-removing master batch, the chain extender and the composite catalyst are added, and solid-phase polycondensation is carried out in stages, so that the melt index of the obtained material is stably between 0.50-0.60 g / 10min (230 DEG C / 2.16kg), and the extrusion swell ratio is less than or equal to 12%, which provides reliable guarantee for stable blow molding of subsequent air pipes, especially complex air pipes with 180-degree turns.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer materials, and particularly relates to a thermoplastic polyester elastomer composite material, a preparation method thereof and an automobile engine air inlet pipe. BACKGROUND

[0002] Thermoplastic polyester elastomer (TPEE) gradually replaces metal for engine air inlet pipe manufacturing due to high toughness, oil resistance and processing convenience. TPEE with a hardness of 55HD becomes a mainstream choice due to flexibility and strength, but there are still the following technical bottlenecks in the processing of complex pipelines (especially 180° sharp bend structure).

[0003] 1. Limitations of traditional tackifying process

[0004] Defects of chain extender application: The traditional tackifying process realizes the melt index (MI) from 10 g / 10 min to 0.5-1.0 g / 10 min (230℃ / 2.16 kg) through chemical chain extension of epoxy and isocyanate extrusion tackifying, which meets the general blow molding needs. However, when blow molding at 180°, the melt elasticity recovery causes the extrusion swell ratio to be >20% (ISO 11443), resulting in the inner wall thickness of the elbow pipe to be reduced and the outer side to be accumulated (wall thickness deviation >15%); the melt rupture frequently occurs under high shear, and the good product rate is less than 60% or even blow molding is not completely formed.

[0005] Uncontrolled acid degradation: TPEE is degraded to produce carboxylic acid in high-temperature processing, which catalyzes the molecular chain to break (the intrinsic viscosity decreases by ≥30%), and the risk of pipe cracking increases after long-term use.

[0006] 2. Deficiencies of existing modification schemes

[0007] Rheological control failure of inorganic fillers: Although the addition of talc, calcium carbonate and the like can inhibit swelling, it causes the material to be brittle (impact strength decreases by 40%), and cannot solve the problem of acid corrosion;

[0008] Single-function nanometer agent dispersion problem: When the acid removal agent such as nano-magnesium oxide is directly added: it agglomerates (the particle size increases from 50 nm to >500 nm) at the solid-phase polycondensation high-temperature stage; the titanium-based catalyst neutralizes the alkaline surface, which makes the TMA chain extension efficiency decrease by more than 50%.

[0009] 3. Urgent needs of the industry

[0010] The automobile air inlet pipeline design is becoming more and more complex (such as 180° sharp bend for turbocharged vehicles), which requires the material to meet the following requirements: precise rheological control: melt index 0.5-0.8 g / 10 min, extrusion swell ratio ≤12%; long-term stability: strength retention rate ≥90% after 150℃ aging for 3000 h; process compatibility: adapt to the existing blow molding production line without the need to modify the equipment. SUMMARY

[0011] Based on this, the purpose of the present application is to provide a thermoplastic polyester elastomer composite material and a preparation method thereof and an automobile engine intake pipe, through the solid phase polycondensation chain extension technology activated by the catalyst, the molecular weight of the TPEE is improved and the rheological performance is precisely controlled in the presence of the nano acid-removing agent, which is suitable for high-precision blow molding parts such as automobile 180° turning.

[0012] To achieve the above-mentioned purpose, the present application adopts the following technical scheme:

[0013] The present application first provides a thermoplastic polyester elastomer composite material, which is prepared from the following components by weight: thermoplastic polyester elastomer resin TPEE 100 parts, chain extender 0.5-1.2 parts, composite catalyst 0.05-0.2 parts, and nano acid-removing master batch 4-10 parts.

[0014] As a further improvement of the above-mentioned scheme of the present application, the nano acid-removing master batch comprises 82wt%-84.5wt% carrier resin, 15wt% phosphate-modified nano magnesium oxide, and 0.5wt%-3wt% dispersant.

[0015] As a further improvement of the above-mentioned scheme of the present application, the preparation method of the nano acid-removing master batch comprises the following steps:

[0016] S11. Dry treatment of the carrier resin and nano magnesium oxide to obtain dried carrier resin and nano magnesium oxide;

[0017] S12. Add the phosphate surface modifier to anhydrous ethanol to obtain a modifier solution, add the dried nano magnesium oxide to the modifier solution, ultrasonic dispersion, centrifugation, drying, to obtain phosphate-modified nano magnesium oxide;

[0018] S13. Premix the dried carrier resin, dispersant, and phosphate-modified nano magnesium oxide in a proportion, then add them to a twin-screw extruder, melt, extrude, granulate, and dry to obtain a nano acid-removing master batch.

[0019] As a further improvement of the above-mentioned scheme of the present application, in step S11, the particle size of the nano magnesium oxide is 30-50nm;

[0020] And / or, in step S12, the concentration of the modifier solution is 5wt%, and the thickness of the modification layer in the phosphate-modified nano magnesium oxide is 2-5nm.

[0021] As a further improvement of the above-mentioned scheme of the present application, the carrier resin is PETG resin, the melt index of the carrier resin under 190℃ and 2.16kg load is 15-25g / 10min; the phosphate surface modifier is triethyl phosphate; and the dispersant is polyether modified polysiloxane dispersant.

[0022] As a further improvement of the above-mentioned scheme of the present application, the composite catalyst is composed of tetrabutyl titanate and zirconium n-propyl alcohol at a mass ratio of 2-4:1; and / or, the hardness of the thermoplastic polyester elastomer resin TPEE is 55HD, and the melt index of the thermoplastic polyester elastomer resin TPEE under 230℃ and 2.16kg load is 10g / 10min; and / or, the chain extender is trimellitic anhydride chain extender.

[0023] The present application also provides a method for preparing the thermoplastic polyester elastomer composite material as mentioned above, which comprises the following steps:

[0024] S21. After the thermoplastic polyester elastomer resin TPEE, the chain extender, the composite catalyst and the nano acid-removing master batch are premixed in proportion, granulation is carried out in a twin-screw extruder to obtain pre-extruded TPEE granules;

[0025] S22. The pre-extruded TPEE granules are first subjected to dehydration condensation in a protective atmosphere: dehydration condensation of TPEE end groups is realized at 130-140℃ for 4-8h, the temperature of 130-140℃ (preferably 130℃) activates the TPEE end groups (-OH / -COOH condensation, the reaction time of 4-8h (preferably 6h) ensures complete dehydration, the flow rate of the protective atmosphere of 10-15L / min can carry out reaction water, inhibit oxidation, the rotation rate of 10-15rpm of the dehydration condensation can strengthen mass transfer and prevent caking; then chain extension reaction is carried out under the condition of vacuum degree ≤0.1kPa and 150-160℃, the reaction time is 10-20h, the TMA acid anhydride is activated to open ring at the temperature of 150-160℃ (preferably 150℃), the reaction time of 10-20h (preferably 15h) can ensure the increase of molecular weight, the vacuum degree of ≤0.1kPa (preferably 0.08kPa) can accelerate the diffusion of by-products and promote the chain extension to proceed in the positive direction, and the rotation rate of 5-8rpm of the chain extension reaction can gently stir and protect the nano dispersion; finally, the thermoplastic polyester elastomer composite material is obtained.

[0026] As a further improvement of the above-mentioned scheme of the present application, in step S1, the length-diameter ratio of the screw of the twin-screw extruder is ≥40:1, and the rotation speed of the high-shear zone block is ≥300rpm; and the granulation is carried out at 220-240℃ and under the condition of die pressure ≤5MPa.

[0027] And / or, the end point determination of the dehydration condensation in step S22 is that the weight loss rate of the material is 0.5wt%-1wt% (detected by the online weighing system); the end point determination condition of the chain extension reaction is that the intrinsic viscosity of the material is 1.80-2.10dL / g (25℃, Ubbelohde viscometer, phenol / tetrachloroethane solution determination).

[0028] The application further provides an automobile engine air inlet pipe formed by blow molding the thermoplastic polyester elastomer composite material.

[0029] As a further improvement of the above-mentioned scheme of the application, the extrusion swell ratio of the automobile engine air inlet pipe is ≤12%, the wall thickness deviation is ≤5%, and the tensile strength retention rate is ≥90% after aging at 150℃ for 3000h.

[0030] Compared with the prior art, the application has the following beneficial effects:

[0031] 1. Breakthrough improvement in processing performance: by adding nano acid-removing masterbatch, chain extender and composite catalyst, and synergistically performing stage-wise solid phase polycondensation, the melt index of the obtained material is stabilized at 0.50-0.60 g / 10min (230℃ / 2.16kg), and the extrusion swell ratio is ≤12%, which provides reliable guarantee for stable blow molding of subsequent air pipes, especially complex air pipes with 180-degree turns;

[0032] 2. Multiple synergistic effects ensure stable improvement in performance: nano rheological regulation inhibits extrusion swell; the phosphate shielding layer protects the activity of the catalyst, inhibits extrusion swell and ensures long-term degradation resistance; stage-wise solid phase polycondensation can regulate the molecular weight distribution and ensure long-term degradation resistance; the addition of the chain extender and the composite catalyst reduces the solid phase reaction temperature and reaction time, greatly improving the efficiency.

[0033] 3. Significant enhancement in long-term thermal stability: the phosphate shielding layer isolates the acid / base reaction, and the nano MgO neutralizes the generated acid in real time, and the strength retention rate is ≥90% after 150℃ / 3000h thermal aging. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to specific embodiments. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0036] The specific information of raw materials used in the following examples and comparative examples is as follows:

[0037] Thermoplastic polyester elastomer resin TPEE: Shore hardness 55D, self-made; the self-made method is as follows: 45 parts of dimethyl terephthalate, 23 parts of 1,4-butanediol, 35 parts of polyether polyol, 0.1 part of 4,4'-bis(α,α-dimethylbenzyl) diphenylamine antioxidant, 0.25 parts of tetrabutyl titanate catalyst, 0.2 parts of trimellitic anhydride crosslinking agent, and 0.3 parts of triphenyl phosphite anti-yellowing agent are added into a polymerization reactor, ester exchange reaction is carried out at 190℃, and polycondensation reaction is carried out at 250℃ under a vacuum degree of 1 mmHg or less, to finally prepare a thermoplastic polyester elastomer resin TPEE with a hardness of 55HD and a melt index of 10 g / 10 min (230℃ / 2.16 Kg);

[0038] Composite catalyst: obtained by mixing tetrabutyl titanate and zirconium n-propyl alcohol according to a weight ratio of 3:1, prepared and used immediately, and sealed from light;

[0039] Nano-magnesium oxide: particle size 40±5 nm, specific surface area ≥60 m 2 / g;

[0040] PETG resin: melt index 20 g / 10 min (190℃ / 2.16 Kg);

[0041] Dispersant: polyether-modified polysiloxane, BYK-2155 of BIK Chemical;

[0042] All materials are commercially available conventional products.

[0043] The above raw materials are only for the purpose of illustrating the source and composition of reagents used in the experiments of the present application, so as to fully disclose, and do not mean that other similar reagents or reagents provided by other suppliers cannot achieve the present application.

[0044] Unless otherwise specified, the reagents, methods and equipment used in the present application are conventional reagents, methods and equipment in the technical field.

[0045] Example 1

[0046] The present embodiment proposes a thermoplastic polyester elastomer composite material, which is prepared from the following components by weight: 100 parts of thermoplastic polyester elastomer resin TPEE, 0.8 parts of trimellitic anhydride (TMA) chain extender, 0.15 parts of composite catalyst, and 8 parts of nano-acid scavenger masterbatch.

[0047] The preparation method of the nano acid-removing master batch of the embodiment comprises the following three steps S11-S13:

[0048] S11. Triethyl phosphate TEP (purity ≥ 99%) is added into anhydrous ethanol (analytically pure, moisture ≤ 0.1%, pretreatment: molecular sieve dehydration) to obtain a TEP ethanol solution with a concentration of 5wt%; nano magnesium oxide (particle size 40±5nm, specific surface area ≥ 60m 2 / g, pretreatment: vacuum drying at 120℃ for 4h) is added into the prepared TEP ethanol solution, ultrasonic dispersion: ultrasonic dispersion at 60℃ for 1h, power 300W, frequency 40kHz, temperature control ≤ 65℃ to prevent agglomeration; centrifugation: centrifugation at a speed of 8000rpm for 10min, vacuum drying: vacuum drying at 50℃ for 12h, to obtain triethyl phosphate modified nano magnesium oxide powder;

[0049] S12. After dry mixing 15 parts of triethyl phosphate modified nano magnesium oxide powder, 83 parts of PETG resin (melt index under the condition of 190℃ / 2.16kg is 20g / 10min, pretreatment: 80℃ air drying for 6h) and 2 parts of dispersant BYK-2155, high-speed stirring: stirring at a speed of 2000rpm for 15min, to obtain a premix (moisture content ≤ 0.03%);

[0050] S13. The premix is melted, extruded and granulated through a co-rotating twin-screw extruder I (L / D=44:1, screw diameter 40mm), dried: vacuum drying at 60℃ for 6h (moisture ≤ 0.02%); sieved: vibration sieve is used to take particles with a particle size of 2-3mm (sieve rate ≥ 95%), which is the nano acid-removing master batch. The process parameters of the co-rotating twin-screw extruder I are shown in Table 1:

[0051] Table 1 Process parameters of co-rotating twin-screw extruder I

[0052]

[0053] The screw speed of the co-rotating twin-screw extruder I is 300rpm, and the torque is ≤ 75%; the feeding rate is 15kg / h, ensuring that the melt residence time is ≤ 90s; the granulation mode is water ring hot cutting (water temperature 40℃, cutter speed 800rpm).

[0054] The preparation method of the thermoplastic polyester elastomer composite material of the embodiment comprises the following four steps S21-S24:

[0055] S21. Raw material pretreatment: thermoplastic polyester elastomer resin TPEE is vacuum dried at 100℃ for 4h, so that its moisture content is ≤50ppm; TMA chain extender is air-dried at 60℃ for 2h, so that its moisture content is ≤0.1%;

[0056] S22. Thermoplastic polyester elastomer resin TPEE, TMA chain extender, and nano acid-removing master batch are added to a high-speed mixer and mixed at a low speed: 500rpm for 5min; then composite catalyst is added and mixed at a high speed: 1500rpm for 3min, with the mixing temperature controlled at ≤40℃, to obtain a mixture;

[0057] S23. The mixture is melted and extruded through a co-rotating twin-screw extruder two (L / D=44:1, screw diameter 50mm), and then drawn and cut into particles: water tank cooling (water temperature 25℃)→air knife water removal→granulator (speed 600rpm, particle size 2-3mm); drying: hot air circulation drying at 80℃ for 30min (moisture content ≤100ppm); sealing and packaging: aluminum foil bag filled with nitrogen (oxygen content ≤0.1%) to obtain pre-extruded TPEE granules (melt index 8.2g / 10min). The equipment configuration of the co-rotating twin-screw extruder two is shown in Table 2 and the process parameters are shown in Table 3.

[0058] Table 2 Equipment configuration of co-rotating twin-screw extruder two

[0059]

[0060] Table 3 Process parameters of co-rotating twin-screw extruder two

[0061]

[0062] S24. Two-stage solid-phase polycondensation:

[0063] (1) Loading and pretreatment: the pre-extruded TPEE granules are loaded into a rotating kettle, with the loading amount being 60%-70% of the volume of the rotating kettle (to avoid accumulation of dead corners), N2 is replaced for 3 times so that the O2 content in the rotating kettle is ≤100ppm, and then it is rotated at a low speed (5rpm) and preheated to 100℃ for 1h to eliminate thermal stress;

[0064] (2) Nitrogen dehydration condensation (first stage): reaction at 130℃ for 7h, with the N2 flow controlled at 10-15L / min, and the weight loss rate is detected by an online weighing system, and when the weight loss rate reaches 0.9wt%, the reaction is stopped; the first-stage reaction equation is:

[0065] TPEE-OH + HOOC-TPEE → TPEE-OCO-TPEE + H2O;

[0066] (3) Vacuum chain extension reaction (second stage): under the condition of vacuum degree 0.06 kPa and 150 °C for 14 h, the rotation rate is 5-8 rpm; the intrinsic viscosity is determined by the Ubbelohde viscometer, and the reaction is stopped when the intrinsic viscosity reaches 1.90 dL / g; the second stage reaction equation is:

[0067] TPEE-OH + TMA → TPEE-OCO-C6H3(COOH)2 + H2O

[0068] TPEE-OCO-C6H3(COOH)2 + HO-TPEE → TPEE-OCO-C6H3(COO-TPEE)2 + H2O;

[0069] (4) Cooling and post-treatment

[0070] Programmed cooling: 150 °C → 100 °C (rate 2 °C / min) under vacuum → N2 replacement and then reduced to 40 °C;

[0071] Anti-oxidation material taking: high-purity N2 (O2≤50 ppm) is filled in the reactor, and the reactor is sealed and transported to the dry room;

[0072] Screening and packaging: fine powder (≤1 mm particles) is removed by a vibrating screen, and an aluminum foil bag is filled with nitrogen and sealed (residual moisture ≤50 ppm), and finally the desired thermoplastic polyester elastomer composite material is obtained.

[0073] Example 2

[0074] The difference between this example and Example 1 is that:

[0075] The thermoplastic polyester elastomer composite material of this example is prepared from the following components by weight: thermoplastic polyester elastomer resin TPEE 100 parts, TMA chain extender 1.2 parts, composite catalyst 0.2 parts, and nano acid-removing master batch 10 parts.

[0076] In step S24 of the preparation method of the thermoplastic polyester elastomer composite material of this example, the vacuum degree gradient of the second stage is set to 0.5 kPa (0-2 h) → 0.2 kPa (2-5 h) → 0.05 kPa (>5 h), and the reaction is stopped when the intrinsic viscosity reaches 2.10 dL / g in the second stage.

[0077] Example 3

[0078] The difference between this example and Example 1 is that:

[0079] The thermoplastic polyester elastomer composite material of this example is prepared from the following components by weight: thermoplastic polyester elastomer resin TPEE 100 parts, TMA chain extender 0.5 parts, composite catalyst 0.05 parts, and nano acid-removing master batch 4 parts.

[0080] The preparation method of the thermoplastic polyester elastomer composite of the present embodiment in step S24: the first stage is reacted at 130°C for 5h, and the weight loss rate is 0.7wt%; the reaction time of the second stage is extended to 18h.

[0081] Comparative Example 1

[0082] The difference between the present comparative example and Example 1 is that:

[0083] The nano acid-removing master batch used in the present comparative example is unmodified nano MgO (40nm);

[0084] Step S24 of the present comparative example adopts single-stage solid-phase polycondensation:

[0085] (1) Loading and pretreatment: load the pre-extruded TPEE pellets into the autoclave, the loading amount is 60%-70% of the volume of the autoclave (to avoid dead corners), replace with N2 for 3 times, so that the O2 content in the autoclave is ≤100ppm, then rotate at low speed (5rpm) and preheat to 100°C for 1h to eliminate thermal stress;

[0086] (2) Single-stage solid-phase polycondensation (i.e. only the first stage of nitrogen dehydration condensation, without the second stage of vacuum chain extension reaction): react at 130°C for 24h under vacuum 0.1kPa, control the N2 flow rate at 10-15L / min, detect the weight loss rate through the online weighing system, and stop the reaction when the weight loss rate reaches 0.9wt%;

[0087] (3) Cooling and post-treatment

[0088] Programmed cooling: 130°C→100°C (rate 2°C / min) under vacuum, then reduce to 40°C after N2 replacement;

[0089] Anti-oxidation material taking: fill the autoclave with high-purity N2 (O2≤50ppm), seal and transfer to the dry room.

[0090] Comparative Example 2

[0091] The difference between the present comparative example and Example 1 is that: the amount of nano acid-removing master batch used in the present comparative example is 3 parts.

[0092] Comparative Example 3

[0093] The difference between the present comparative example and Example 1 is that: the amount of nano acid-removing master batch used in the present comparative example is 12 parts.

[0094] Comparative Example 4

[0095] The difference between the present comparative example and Example 1 is that:

[0096] Step S24 of the present comparative example adopts single-stage solid-phase polycondensation:

[0097] (1) Loading and pretreatment: the pre-extruded TPEE pellets were loaded into the autoclave, the loading amount was 60%-70% of the volume of the autoclave (to avoid accumulation of dead corners), N2 was replaced for 3 times, so that the O2 content in the autoclave was ≤100 ppm, then preheated to 100℃ for 1h at low speed (5 rpm) to eliminate thermal stress;

[0098] (2) Single-stage solid phase polycondensation (i.e. directly into the second stage solid phase polycondensation, i.e. vacuum chain extension reaction): under vacuum 0.06 kPa, 150℃ for 21h, the intrinsic viscosity was determined by Ubbelohde viscometer, when the intrinsic viscosity ≥1.60 dL / g, the reaction was stopped;

[0099] (3) Cooling and post-treatment

[0100] Programmed cooling: 150℃→100℃ (rate 2℃ / min) under vacuum→ N2 replaced to 40℃;

[0101] Anti-oxidation material taking: the autoclave was filled with high-purity N2 (O2≤50 ppm), sealed and transferred to the dry room.

[0102] Comparative Example 5

[0103] The difference between this comparative example and Example 1 is that no composite catalyst is used in this comparative example.

[0104] The amount of each component in Examples 1-3 and Comparative Examples 1-5 is shown in Table 4.

[0105] Table 4 Amount of each component in Examples 1-3 and Comparative Examples 1-5 (parts by weight)

[0106]

[0107] Test Example

[0108] The composite materials prepared in Examples 1-3 and Comparative Examples 1-5 were tested for the following properties: melt index (230℃ / 2.16 kg); extrusion swell ratio (180° elbow): according to ISO 11443; strength retention rate after 150℃ aging for 3000h: according to ISO 527; the test results are shown in Table 5.

[0109] Table 5 Test results

[0110]

[0111] According to the results in Table 1:

[0112] Example 1-3 solves the three defects of TPEE tackifying technology by using phosphate-modified nano-MgO combined with a staged solid-phase chain extension process: first, it solves the problem of catalyst deactivation, and the melt index is stable and controllable, with a melt index of 0.50-0.60 g / 10 min; second, it solves the problem of rheological stability by adding nano-acid-removing masterbatch, and solves the problem of extrusion swell, with an extrusion swell of 9.5%-12%, fully meeting the complex pipe blow molding of automobile 180° turning; third, it increases the molecular weight by relatively low-temperature chain extension and shields the acid / base reaction with a phosphate shield layer + nano-MgO to neutralize and degrade the generated acid in real time, with a 150℃ / 3000h thermal aging strength retention rate of ≥90%, meeting the long-term high-temperature requirements of engine intake pipes.

[0113] Compared with Example 1, Comparative Example 1 uses unmodified nano-magnesium oxide and adopts a single-stage solid-phase polycondensation, resulting in complex catalyst deactivation, insufficient chain extension, uncontrollable melt index, and rheological control failure due to nano-agglomeration, with an extrusion swell of 23%, and the strength retention rate is greatly reduced due to insufficient acid neutralization.

[0114] Compared with Example 1, Comparative Example 2 uses a small amount of nano-acid-removing masterbatch, resulting in insufficient acid neutralization, residual carboxyl catalytic degradation, a melt index of 0.72 g / min, and rheological control failure due to insufficient nano-dosage, with an extrusion swell of 15.8%; acid corrosion is not completely inhibited, reducing the strength retention rate.

[0115] Compared with Example 1, Comparative Example 3 uses a large amount of nano-acid-removing masterbatch, which hinders molecular chain movement, reduces the melt index, and causes insufficient melt elasticity due to excessive rheological control, reducing the extrusion swell, and nano-agglomerates cause brittleness, reducing the strength retention rate.

[0116] Compared with Example 1, Comparative Example 4 directly uses a single-stage solid-phase polycondensation without staged solid-phase polycondensation, resulting in dehydration and chain extension competition, catalyst deactivation, uncontrollable melt index, and irreversible agglomeration of nano-acid-removing masterbatch at 150℃ under vacuum, single-stage reaction causing molecular weight distribution to worsen, leading to extrusion swell, and uncontrollable acid degradation reducing the strength retention rate.

[0117] Compared with Example 1, Comparative Example 5 does not use a complex catalyst, and the melt index of Comparative Example 5 reaches 1.10 g / min, which may be due to the low activation of TMA chain extender, resulting in low chain extension reaction rate; the extrusion swell of Comparative Example 5 is 20.8%, which may be due to the relatively low molecular weight melt elasticity recovery; the strength retention rate of Comparative Example 5 is only 72%, which is because the molecular chain breakage is not inhibited due to the reliance on nano-acid-removing.

[0118] Any combination of the technical features in the above-described embodiments can be made, and for the sake of brevity, not all possible combinations are described, however, as long as the combination of the technical features does not exist in contradiction, it shall be considered within the scope of the present disclosure.

[0119] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it shall not be understood as a limitation on the patent scope of the present application. It shall be pointed out that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these shall be within the protection scope of the present application. Therefore, the protection scope of the present application patent shall be subject to the appended claims.

Claims

1. A thermoplastic polyester elastomer composite material, characterized in that, It is prepared from the following components in parts by weight: 100 parts of thermoplastic polyester elastomer resin TPEE, 0.5-1.2 parts of chain extender, 0.05-0.2 parts of composite catalyst, and 4-10 parts of nano-acid-removing masterbatch; the nano-acid-removing masterbatch contains 82wt%-84.5wt% carrier resin, 15wt% phosphate-modified nano-magnesium oxide, and 0.5wt%-3wt% dispersant; the composite catalyst is composed of tetrabutyl titanate and zirconium propoxide in a mass ratio of 2-4:1; the preparation method of the thermoplastic polyester elastomer composite material includes the following steps: S21. Thermoplastic polyester elastomer resin TPEE, chain extender, composite catalyst and nano deacidifying masterbatch are premixed in proportion and then added to a twin-screw extruder for granulation to obtain pre-extruded TPEE granules. S22. The pre-extruded TPEE granules are first dehydrated and condensed under a protective atmosphere: the reaction is carried out at 130-140℃ for 4-8 hours; then the chain extension reaction is carried out under vacuum degree ≤0.1kPa and 150-160℃ for 10-20 hours to obtain a thermoplastic polyester elastomer composite material.

2. The thermoplastic polyester elastomer composite material according to claim 1, characterized in that, The preparation method of the nano-acid-removing masterbatch includes the following steps: S11. Dry the carrier resin and nano-magnesium oxide to obtain dried carrier resin and nano-magnesium oxide; S12. Add the phosphate ester surface modifier to anhydrous ethanol, mix to obtain a modifier solution, add the dried nano magnesium oxide to the modifier solution, ultrasonically disperse, centrifuge, and dry to obtain phosphate ester modified nano magnesium oxide; S13. The dried carrier resin, dispersant, and phosphate-modified nano magnesium oxide are premixed in proportion, then added to a twin-screw extruder, melted, extruded, granulated, and dried to obtain nano deacidification masterbatch.

3. The thermoplastic polyester elastomer composite material according to claim 2, characterized in that, In step S11, the particle size of the nano-magnesium oxide is 30-50 nm; And / or, in step S12, the concentration of the modifier solution is 5 wt%, and the thickness of the modification layer in the phosphate-modified nano-magnesium oxide is 2-5 nm.

4. The thermoplastic polyester elastomer composite material according to claim 2, characterized in that, The carrier resin is PETG resin, and the melt index of the carrier resin at 190℃ and 2.16kg load is 15-25g / 10min; the phosphate ester surface modifier is triethyl phosphate; and the dispersant is polyether-modified polysiloxane dispersant.

5. The thermoplastic polyester elastomer composite material according to claim 1, characterized in that, The thermoplastic polyester elastomer resin TPEE has a hardness of 55HD and a melt index of 10g / 10min at 230℃ and 2.16kg load; and / or, the chain extender is trimellitic anhydride chain extender.

6. The thermoplastic polyester elastomer composite material according to claim 1, characterized in that, In step S21, the twin-screw extruder has a screw length-to-diameter ratio ≥40:1 and a high-shear block speed ≥300 rpm; the granulation is carried out at 220-240℃ and a die pressure ≤5MPa. And / or, in step S22, the weight loss rate of the material after dehydration and condensation is 0.5wt%-1wt%, and the intrinsic viscosity of the material after chain extension reaction is 1.80-2.10 dL / g.

7. An intake manifold for an automobile engine, characterized in that, It is made by blow molding of a thermoplastic polyester elastomer composite material as described in any one of claims 1-6.

8. The automobile engine intake manifold according to claim 7, characterized in that, The extrusion swell rate of the automobile engine intake pipe is ≤12%, the wall thickness deviation is ≤5%, and the tensile strength retention rate is ≥90% after aging at 150℃ for 3000h.

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