A tpu-based damping composite material and a preparation method thereof

Abstract

The application discloses a TPU-based damping composite material and a preparation method thereof. The TPU-based damping composite material is composed of two parts of A component and B component arranged alternately, wherein the A component comprises the following components in parts by weight: TPU 1 100; the B component comprises the following components in parts by weight: TPU 2 48~63 phenolic resin, 27~32, filler 10~20; the TPU 1 is a TPU of polyester dihydric alcohol, diphenyl methane diisocyanate (MDI) and 1,4-butanediol (BDO); and the TPU 2 is a TPU of polycarbonate dihydric alcohol (PCDL), diphenyl methane diisocyanate (MDI) and 1,4-butanediol (BDO). The TPU-based damping composite material has a wide effective damping temperature range (tan delta > 0.3) and good mechanical properties; and the preparation method is a continuous process, has high preparation efficiency and low energy consumption.

Description

Technical Field

[0001] This invention belongs to the field of damping material technology, specifically relating to a TPU-based damping composite material and its preparation method. Background Technology

[0002] Polyurethane materials have a microphase separation structure and good overall performance, making them suitable as damping materials for vibration reduction and noise reduction in fields such as construction, transportation, and industrial equipment. However, the effective damping temperature range (tanδ > 0.3) of traditional single-component polyurethane materials is relatively narrow (approximately 30-40 °C), making it difficult to meet the demand for wider temperature range damping performance in extreme temperature environments.

[0003] Composite material technology combines two or more materials with different properties through physical or chemical methods. By leveraging the complementary and synergistic effects between the components, it can effectively broaden the damping temperature range of a single material and improve its overall performance. Among these, alternating multilayer composite damping materials achieve synergistic enhancement of damping performance through a multilayer alternating structure design. Their preparation methods are simple and easy to mass-produce, leading to their widespread application in the automotive, rail transportation, industrial equipment, and aerospace industries. Notably, in fields with stringent performance requirements such as rail transportation and aerospace, these materials, in addition to excellent damping performance, also require good tensile strength and elongation at break.

[0004] Currently, the most researched and applied alternating multilayer damping materials are prepared using a twin-screw co-extrusion process, with an alternating arrangement of damping layers and constraint layers. The damping layers are typically made of rubber, with some using polyurethane; the constraint layers are mainly made of rigid plastics such as polymethyl methacrylate, polyvinyl chloride, and epoxy resin.

[0005] CA103342034A is a composite damping material prepared by alternating layers of rubber damping layers and plastic constraint layers. The resulting composite damping material has 16 to 32 layers, a high peak damping strength, and a wide effective damping temperature range, but poor mechanical properties, with a maximum tensile strength of 17.5 MPa and a maximum elongation at break of 120%. Due to the differences in the properties of different materials, compatibilizers are often needed in practical applications to improve the interlayer bonding force and prevent interlayer cracking.

[0006] CN115771250A discloses a butyl rubber / natural rubber alternating multilayer composite material. The method first involves mixing raw rubber to obtain a natural rubber compound and a butyl rubber compound, which are then cut to sizes suitable for extrusion. These are then co-extruded by alternating layers to obtain 2-16 layer alternating composite sheets. Finally, the sheets are vulcanized and cross-linked to obtain the finished damping composite material with a maximum tensile strength of 15 MPa. Furthermore, the high elasticity of rubber increases the difficulty of the extrusion process, requiring greater torque and placing higher demands on the production equipment.

[0007] CN114015377A discloses a wide-temperature-range gradient multilayer damping material, which uses butyl rubber or its derivatives as the damping layer and chopped glass fiber modified epoxy resin or its derivatives as the constraint layer. The two are made into thin sheets of different thicknesses and are stacked and bonded together to obtain a composite damping material with a maximum of 8 layers. The damping performance is poor, with tanδ values ​​below 0.3 in the range of -30 °C to 70 °C.

[0008] The above methods mostly use different types of materials as the matrix to prepare composite damping materials, and the bonding force at the layer interface is the key to restricting the performance of composite damping materials.

[0009] The literature (Study on Damping Performance Regulation and Mechanism of Thermoplastic Polyurethane Hybrid System. Sichuan University, 2017) prepared an alternating multilayer damping composite material based on the same thermoplastic polyurethane (hereinafter referred to as "TPU"). The interlayer interface bonding force was strong and there was no delamination phenomenon, but the effective damping temperature range (tanδ>0.3) was narrow, at 49.5°C. Summary of the Invention

[0010] To address the problems existing in the prior art, this invention provides a TPU-based damping composite material and its preparation method. The TPU-based damping composite material has a wide effective damping temperature range (tanδ>0.3) and good mechanical properties. The preparation method is a continuous process with high preparation efficiency and low energy consumption.

[0011] The first aspect of this invention provides a TPU-based damping composite material, which is composed of two parts, A and B, arranged alternately. (1) Component A, by weight, comprises: TPU 1 100 (2) Component B, by weight, comprises: TPU 2 48 ~ 63 Phenolic resin 27 ~ 32 Packing material 10 ~ 20 The TPU1 is a TPU of polyester diol, diphenylmethane diisocyanate (MDI), or 1,4-butanediol (BDO). The TPU 2 is a type of TPU such as polycarbonate diol (PCDL), diphenylmethane diisocyanate (MDI), or 1,4-butanediol (BDO).

[0012] The layer thickness ratio of component A to component B is 1:1 to 1:1.5; the single layer thickness of component A is 0.020 mm to 0.030 mm; and the single layer thickness of component B is 0.020 mm to 0.045 mm.

[0013] The TPU-based damping composite material of the present invention has a total of 64 layers and a total thickness of 1.28 mm to 2.40 mm.

[0014] Preferably, the TPU 1 of the present invention has a Shore hardness of 68A to 74A, more preferably Shore 70 to 71A; the glass transition temperature of the TPU 1 is -30 °C to -18 °C, more preferably -27 °C to -23 °C; and the number-average molecular weight of the TPU 1 is 120,000 g / mol to 140,000 g / mol. The polyester diol is one of polyethylene adipate diol, polyhexyl adipate diol, polybutylene adipate hexanediol copolyester diol, and polyethylene adipate diol, with a number-average molecular weight of 1000 to 1600 g / mol; preferably, polyethylene adipate diol (PEA) with a number-average molecular weight of 1400 to 1600 g / mol.

[0015] Preferably, the TPU2 of the present invention has a Shore hardness of 84A to 87A, more preferably Shore 86A; the glass transition temperature of the TPU2 is -8 °C to 2 °C, more preferably -6 °C to -4 °C; the number-average molecular weight of the TPU2 is 90,000 g / mol to 110,000 g / mol. The number-average molecular weight of the polycarbonate diol is 900 to 1200 g / mol.

[0016] The phenolic resin of this invention has a softening point of 93-97 °C and a number-average molecular weight of 800-1200 g / mol.

[0017] The filler refers to one or more of the following: carbon black, mica, calcium carbonate, montmorillonite, and talc, all of which are commercially available general-purpose fillers.

[0018] A second aspect of this invention provides a method for preparing the TPU-based damping composite material, comprising the following steps: (1) Preparation of component B: TPU 2, phenolic resin and filler were added to a twin-screw extruder in proportion and then blended and granulated to obtain component B; (2) Preparation of damping composite material: Component A and component B are added to extruder 1 and extruder 2 respectively. The melt from extruder 1 and extruder 2 is aggregated into a melt with a two-layer structure "component A-component B" under the action of the manifold. The TPU-based damping composite material with alternating distribution of component A and component B is obtained by layer cutting and stacking module.

[0019] Preferably, in step (1), the screw temperature is 160 °C to 190 °C.

[0020] Preferably, in step (1), the extrusion temperature of extruder 1 and extruder 2 is set to 160°C~180°C.

[0021] This invention adjusts the layer thickness ratio of component A and component B by regulating and controlling the rotational speed ratio of the two extruders. The relationship between the number of layers N of the damping composite material and the number of layer cutting and stacking modules n is N = 2. n+1 When the number of layer cutting and stacking modules is 3, a damping composite material with 64 layers of alternating "component A – component B" is obtained in one step, as shown in the schematic diagram below. Figure 1 As shown.

[0022] This invention achieves the beneficial effects of a wide effective damping temperature range and good mechanical properties in TPU-based damping composite materials by controlling the composition and ratio of components A and B, the layer thickness ratio between components A and B, and the total number of layers and total thickness of the TPU-based damping composite material. The specific beneficial technical effects are as follows: (1) The TPU-based damping composite material provided by the present invention has a wide effective damping temperature range (damping loss factor tanδ>0.3), an effective damping temperature range (tanδ>0.3) ≥65°C, a tensile strength ≥26MPa, an elongation at break ≥350%, and good mechanical properties.

[0023] (2) The TPU-based damping composite material provided by the present invention has good interlayer bonding force and stable quality.

[0024] (3) The TPU-based damping composite material provided by the present invention is prepared by continuous molding process, which has high production efficiency, low production cost and broad industrialization and market prospects. Instruction manual illustrations

[0025] Figure 1 This is a schematic diagram of the structure of the TPU-based alternating multilayer damping composite material of the present invention.

[0026] Figure 2 These are comparison diagrams of dynamic thermomechanical analysis (DMA) of the TPU-based alternating multilayer damping composite materials prepared in Examples 1-3 and Comparative Examples 1-4. Detailed Implementation

[0027] The present invention will be further described below with reference to the embodiments. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0028] The TPU used in components A and B in the examples and comparative examples was obtained by reacting the raw materials in the parts by weight in Table 1: the polyol, isocyanate and chain extender in the parts by weight in Table 1 were added to the twin-screw extruder through a mixing system and mixed and reacted. The temperature of the screw was controlled at 140 ~ 220 °C. The resulting polymer melt was pelletized underwater and dried to obtain TPU1 and TPU2 in the examples and comparative examples.

[0029] Table 1. Composition of TPU in the Examples and Comparative Examples

[0030] The TPUs prepared in the examples and comparative examples were subjected to the following performance tests: Hardness: determined according to GB / T 531.1-2008; Glass transition temperature: determined according to GB / T 19466.2-2004; Molecular weight: determined according to GB / T 21863-2008. The performance data results are shown in Table 2 below: Table 2 Performance of TPUs in Examples and Comparative Examples

[0031] The TPU-based alternating multilayer damping composite materials in the examples and comparative examples were obtained by co-extrusion of raw materials in the following three parts by weight as shown in Table 3, wherein the phenolic resin is grade PF2123S (Jinan Dahui Chemical Technology Co., Ltd.) and the mica is grade GA-1 (Anhui Gree New Material Technology Co., Ltd.): Table 3. TPU-based alternating multilayer damping composite materials of the examples and comparative examples

[0032] The TPU-based alternating multilayer damping composites prepared in the examples and comparative examples were subjected to the following performance tests: Damping performance: determined according to ASTM D5026-15; Tensile strength and elongation at break: determined according to GB / T 528-2009. The damping performance data results are shown below. Figure 2 See Table 4 below, and Table 5 for the tensile strength and elongation at break data.

[0033] Table 4 Damping performance of the examples and comparative examples

[0034] Table 5 Tensile strength and elongation at break of the examples and comparative examples

[0035] From Table 4, Table 5 and Figure 2It can be seen that the TPU-based alternating multilayer damping composite materials prepared in Examples 1-3 of the present invention all have two damping peaks, and the two damping peaks partially overlap. The effective damping temperature range when the loss factor tanδ > 0.3 is > 60 °C, and the widest range can reach 69.5 °C. The tensile strength and elongation at break are good. Comparative Example 1 uses a single component A material, which exhibits a single damping peak. Although the elongation at break is high, the tensile strength is slightly reduced, but the damping temperature range is extremely narrow. In Comparative Examples 2 and 3, the two damping peaks of the TPU-based alternating multilayer damping composite materials cannot effectively overlap. The effective damping temperature range when the loss factor tanδ > 0.3 becomes narrower, and both the tensile strength and elongation at break decrease.

Claims

1. A TPU-based damping composite material, comprising alternating components A and B, (1) Component A, by weight, comprises: TPU 1 100 (2) Component B, by weight, comprises: TPU 2 48 ~ 63 Phenolic resin 27 ~ 32 Packing material 10 ~ 20 The TPU1 is a TPU of polyester diol, diphenylmethane diisocyanate (MDI), or 1,4-butanediol (BDO). The TPU 2 is a type of TPU such as polycarbonate diol (PCDL), diphenylmethane diisocyanate (MDI), or 1,4-butanediol (BDO).

2. The TPU-based damping composite material according to claim 1, characterized in that, The layer thickness ratio of component A to component B is 1:1 to 1:1.5; the single layer thickness of component A is 0.020 mm to 0.030 mm; and the single layer thickness of component B is 0.020 mm to 0.045 mm.

3. The TPU-based damping composite material according to claim 1, characterized in that, The TPU-based damping composite material has a total of 64 layers and a total thickness of 1.28 mm to 2.40 mm.

4. The TPU-based damping composite material according to claim 1, characterized in that, The TPU 1 has a Shore hardness of 68A to 74A, a glass transition temperature of -30 °C to -18 °C, and a number-average molecular weight of 120,000 g / mol to 140,000 g / mol.

5. The TPU-based damping composite material according to claim 1, characterized in that, The polyester diol is one of polyethylene adipate diol, polyethylene adipate diol, polybutylene adipate hexanediol copolyester diol, and polyethylene adipate diol.

6. The TPU-based damping composite material according to claim 1, characterized in that, The number average molecular weight of polyester diols is 1000 ~ 1600 g / mol.

7. The TPU-based damping composite material according to claim 1, characterized in that, The TPU2 has a Shore hardness of 84A to 87A, a glass transition temperature of -8 °C to 2 °C, and a number-average molecular weight of 90,000 g / mol to 110,000 g / mol.

8. The TPU-based damping composite material according to claim 1, characterized in that, The polycarbonate diol has a number-average molecular weight of 900 to 1200 g / mol.

9. The TPU-based damping composite material according to claim 1, characterized in that, The filler refers to one or more of the following: carbon black, mica, calcium carbonate, montmorillonite, and talc.

10. A method for preparing a TPU-based damping composite material according to any one of claims 1-9, comprising the following steps: (1) Preparation of component B: TPU 2, phenolic resin and filler were added to a twin-screw extruder in proportion and then blended and granulated to obtain component B; (2) Preparation of damping composite material: Component A and component B are added to extruder 1 and extruder 2 respectively. The melt from extruder 1 and extruder 2 is converged into a melt with a two-layer structure "component A-component B" under the action of the manifold. The TPU-based damping composite material with alternating distribution of component A and component B is obtained by the layer cutting and stacking module.

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