Thermoplastic polyurethane elastomer with high-efficiency thermal welding performance and preparation method thereof
By adding reinforcement to the thermoplastic polyurethane elastomer to form a dense network structure, the problem of material aging and decreasing hot welding fastness after long-term placement or high-temperature baking is solved, and its temperature resistance and thermal welding performance are significantly improved.
Patent Information
- Application Number
- CN202411977545.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-04-08
AI Technical Summary
After long-term placement or high-temperature baking, the molecular segments of existing thermoplastic polyurethane elastomers will crack, resulting in material aging and reduced thermal welding fastness, limiting their application range.
By adding enhancers with hydroxyl groups on the surface or forming more hydrogen bonding, such as silica, graphene oxide, etc., the hydrogen bonding between molecular chain segments is enhanced, a dense network structure is formed, molecular chain breakage and small molecules are restricted, and the temperature resistance and thermal welding performance of the material are improved.
It significantly enhances the temperature resistance and thermal welding performance of thermoplastic polyurethane elastomers, prevents aging and cracking, improves the hydrolysis resistance of splines after thermal welding, and ensures the firmness and quality stability of the product after processing and molding.
Abstract
Description
Technical Field
[0001] The invention relates to a thermoplastic polyurethane and a preparation method thereof, in particular to a thermoplastic polyurethane elastomer with high-efficiency thermal welding performance and a preparation method thereof, belonging to the technical field of polymer materials. Background Art
[0002] Thermoplastic polyurethane elastomer, also known as thermoplastic polyurethane rubber, abbreviated as TPU, is a typical multi-block copolymer with many advantages such as good wear resistance, wide hardness range, high strength, high elongation, large load support capacity, good shock absorption effect, good low temperature resistance and excellent oil and weather resistance. Thermoplastic polyurethane elastomer has a wide range of applications, involving textiles, medical, construction, building materials, automobiles, national defense, light industry, chemical industry, electronics, aerospace, aviation, etc.
[0003] According to different processing methods, polyurethane elastomers can generally be divided into one-step method and prepolymer method; the one-step method uses given raw materials, in certain equipment, to mix polyester, diisocyanate (MDI), and low molecular weight diol (BDO) in a certain ratio to make TPU; if two components are used: MDI is often one component, and polyester and BDO are mixed into one component; prepolymer method: first prepolymerize polyester and MDI, and then use BDO to extend the chain to generate TPU.
[0004] However, after long-term storage or high-temperature baking, the molecular chain segments of existing thermoplastic polyurethane elastomers will continue to break down, causing material aging or deep small molecule additives to migrate to the surface, reducing the bonding performance of the elastomer in subsequent thermal welding processing steps, greatly limiting its application range. Summary of the invention
[0005] In view of this, the present invention provides a thermoplastic polyurethane elastomer with high-efficiency heat welding performance and a preparation method thereof, so as to solve the problem in the prior art that the heat welding fastness of the polyurethane elastomer decreases after long-term storage or high-temperature baking, enhance the physical properties of the thermoplastic polyurethane elastomer, and enhance its temperature resistance.
[0006] In order to achieve the above object, the present invention adopts the following technical solution:
[0007] A thermoplastic polyurethane elastomer with high-efficiency heat welding performance comprises the following raw materials in parts by weight:
[0008] 25-50 parts of diisocyanate, 30-40 parts of polyol, 3-15 parts of chain extender, 0.5-3 parts of catalyst, 1-3 parts of ultraviolet light absorber, 0.5-3 parts of antioxidant and 0.5-2 parts of lubricant.
[0009] On the basis of the above technical solution, the present invention further defines the solution as follows:
[0010] Furthermore, it also includes 0.5-15 parts of a reinforcing agent.
[0011] Furthermore, the reinforcing agent is an active substance having a hydroxyl group on the surface or capable of forming a large number of hydrogen bonds, preferably any one of silicon dioxide, titanium dioxide, graphene oxide, molecular sieves, and montmorillonite, or a mixture of several thereof. The reinforcing agent enhances the hydrogen bonding between molecular chain segments in the polyurethane material, forms a dense network structure, limits the molecular chain breakage and the migration rate of small molecules, and at the same time improves the temperature resistance of the material to ensure good thermal welding performance.
[0012] Furthermore, the polyol is any one of tetrahydrofuran-propylene oxide copolymer glycol and polytetramethylene ether glycol, which can effectively improve the heat resistance of the obtained thermoplastic polyurethane, thereby facilitating the improvement of the temperature resistance of the final polyurethane film.
[0013] The chain extender is any one of 1,3-propylene glycol, 1,4-butanediol, 4,4′-xylene methane-5-maleimide, and hydroquinone bis(hydroxyethyl) ether, or a mixture of several of them.
[0014] The catalyst is any one of dibutyltin dilaurate, stannous oleate and stannous octoate.
[0015] The ultraviolet light absorber is any one of UV-327, UV-328, UV-329, UV-360, UV-571, UV-1130, and UV-1300, or a mixture of several thereof.
[0016] The antioxidant is any one of butyl para-oxybenzoate and M-benzene.
[0017] The lubricant is any one of calcium stearate, zinc stearate, pentaerythritol stearate, and oleic acid amide, or a mixture of several of them.
[0018] The present invention also provides a method for preparing the thermoplastic polyurethane elastomer with high-efficiency heat welding performance: the raw materials are mixed, a molten mixed colloid is obtained by a twin-screw extruder, and the molten mixed colloid is cast and then cooled and formed by a cooling roller.
[0019] Further, the extrusion temperature of the twin-screw extruder is 170-230°C, the extrusion pressure is 9-23MPa, and the rotation speed is 20-120rpm;
[0020] The cooling roller temperature is 10-55°C.
[0021] The beneficial effects of the present invention are:
[0022] The thermoplastic polyurethane elastomer prepared by the present invention significantly enhances the temperature resistance of the thermoplastic polyurethane elastomer by adding a proper amount of reinforcing agent, prevents the thermoplastic polyurethane elastomer from aging and cracking due to high temperature, improves the hydrolysis resistance of the specimen after heat welding, and can maintain good performance after being soaked in 5% salt water. It has excellent strength and retention rate, can effectively reduce the aging degree of the thermoplastic polyurethane elastomer after long-term storage and high-temperature baking, and provides a guarantee for the subsequent heat welding process, improves the welding strength of the thermoplastic polyurethane elastomer, and ensures the firmness and quality stability of the product after processing and molding. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0024] Example 1
[0025] Thermoplastic polyurethane elastomer with high efficiency heat welding performance, the preparation method is as follows:
[0026] The raw materials were mixed according to 30kg of diisocyanate, 35kg of polyol, 10kg of chain extender, 10kg of reinforcing agent, 2kg of catalyst, 2kg of ultraviolet light absorber, 2kg of antioxidant and 1kg of lubricant, and a molten mixed colloid was obtained by a twin-screw extruder at an extrusion temperature of 200°C, an extrusion pressure of 18MPa and a rotation speed of 100rpm. After casting, the mixture was cooled and formed by a cooling roller at 45°C.
[0027] Among them, the polyol is tetrahydrofuran-propylene oxide copolymer glycol, the chain extender is a mixture of 1,3-propylene glycol and 4,4′-xylene methane-5-maleimide, the reinforcing agent is a mixture of silicon dioxide, titanium dioxide, molecular sieves, and montmorillonite, the catalyst is dibutyltin dilaurate, the ultraviolet light absorber is a mixture of UV-327, UV-328, and UV-329, the antioxidant is bis(butyl paraoxybenzoate), and the lubricant is a mixture of calcium stearate and zinc stearate.
[0028] The obtained products were subjected to performance testing, and the test items, methods and results are recorded in Table 1.
[0029] Table 1 Product performance test in Example 1
[0030] Test items Test Method Measured value Thickness(mm) TeclockSM-114 0.32 Hardness(A) ASTM-D2240SHOREA 88 Tensile strength (longitudinal) (Mpa) ASTM-D412(Type C) 41.6 Tensile strength (horizontal) (Mpa) ASTM-D412(Type C) 40.1 Tear strength (longitudinal) (kgf / cm) ASTM-D624(Right angle type) 110.3 Tear strength (horizontal) (kgf / cm) ASTM-D624(Right angle type) 107.6 <![CDATA[Specific gravity (g / cm 3 )]]> / 0.7 Heat seal strength (normal) (kgf) ASTMF2029 11.4 Heat seal strength (water) (kgf) ASTMF2029 10.6 Strength retention rate (water) (%) / 93.0 Heat seal strength (5% salt water) (kgf) ASTMF2029 10.3 Strength retention rate (5% salt water) (%) / 90.0
[0031] Example 2
[0032] Thermoplastic polyurethane elastomer with high efficiency heat welding performance, the preparation method is as follows:
[0033] The raw materials were mixed according to 25kg of diisocyanate, 30kg of polyol, 3kg of chain extender, 0.5kg of reinforcing agent, 0.5kg of catalyst, 1kg of ultraviolet light absorber, 0.5kg of antioxidant and 0.5kg of lubricant, and a molten mixed colloid was obtained by a twin-screw extruder at an extrusion temperature of 170°C, an extrusion pressure of 9MPa and a rotation speed of 20rpm. After casting, the mixture was cooled on a cooling roller at 10°C to form a molten mixed colloid.
[0034] Among them, the polyol is tetrahydrofuran-propylene oxide copolymer glycol, the chain extender is hydroquinone bis(hydroxyethyl) ether, the enhancer is a mixture of molecular sieve and montmorillonite, the catalyst is stannous octoate, the ultraviolet light absorber is a mixture of UV-329, UV-360 and UV-1300, the antioxidant is M-benzene, and the lubricant is pentaerythritol stearate.
[0035] Example 3
[0036] Thermoplastic polyurethane elastomer with high efficiency heat welding performance, the preparation method is as follows:
[0037] The raw materials were mixed according to 50kg of diisocyanate, 40kg of polyol, 15kg of chain extender, 15kg of reinforcing agent, 3kg of catalyst, 3kg of ultraviolet light absorber, 3kg of antioxidant and 2kg of lubricant, and a molten mixed colloid was obtained by a twin-screw extruder at an extrusion temperature of 230°C, an extrusion pressure of 23MPa and a rotation speed of 120rpm. After casting, the mixture was cooled and formed by a cooling roller at 55°C.
[0038] Among them, the polyol is tetrahydrofuran-propylene oxide copolymer glycol, the chain extender is a mixture of 4,4′-xylene methane-5-maleimide and hydroquinone bis(hydroxyethyl) ether, the enhancer is a mixture of graphene oxide and molecular sieves, the catalyst is stannous oleate, the ultraviolet light absorber is a mixture of UV-329, UV-360 and UV-1300, the antioxidant is bis(butyl paraoxybenzoate), and the lubricant is a mixture of pentaerythritol stearate and oleamide.
[0039] Example 4
[0040] Thermoplastic polyurethane elastomer with high efficiency heat welding performance, the preparation method is as follows:
[0041] The raw materials were mixed according to 40kg of diisocyanate, 35kg of polyol, 12kg of chain extender, 8kg of reinforcing agent, 1kg of catalyst, 1kg of ultraviolet light absorber, 1kg of antioxidant and 1kg of lubricant, and a molten mixed colloid was obtained by a twin-screw extruder at an extrusion temperature of 180°C, an extrusion pressure of 15MPa and a rotation speed of 80rpm. After casting, the mixture was cooled and formed by a cooling roller at 25°C.
[0042] Among them, the polyol is tetrahydrofuran-propylene oxide copolymer glycol, the chain extender is 4,4′-xylene methane-5-maleimide, the reinforcing agent is a mixture of graphene oxide and montmorillonite, the catalyst is stannous octoate, the ultraviolet light absorber is a mixture of UV-360 and UV-1300, the antioxidant is bis(butyl para-oxybenzoate), and the lubricant is pentaerythritol stearate.
[0043] Example 5
[0044] Thermoplastic polyurethane elastomer with high efficiency heat welding performance, the preparation method is as follows:
[0045] The raw materials were mixed according to 45kg of diisocyanate, 35kg of polyol, 10kg of chain extender, 10kg of reinforcing agent, 2kg of catalyst, 2kg of ultraviolet light absorber, 1kg of antioxidant and 1kg of lubricant, and a molten mixed colloid was obtained by a twin-screw extruder at an extrusion temperature of 180°C, an extrusion pressure of 18MPa and a rotation speed of 100rpm. After casting, the mixture was cooled and formed by a cooling roller at 30°C.
[0046] Among them, the polyol is tetrahydrofuran-propylene oxide copolymer glycol, the chain extender is a mixture of 1,4-butanediol and hydroquinone bis(hydroxyethyl) ether, the enhancer is any one of graphene oxide, molecular sieve, and montmorillonite or a mixture of several of them, the catalyst is any one of dibutyltin dilaurate, stannous oleate, and stannous octoate, the ultraviolet light absorber is a mixture of UV-327, UV-328, UV-329, and UV-1300, the antioxidant is M-benzene, and the lubricant is pentaerythritol stearate.
Claims
1. A thermoplastic polyurethane elastomer with high-efficiency thermal welding performance, characterized in that: The invention comprises the following raw materials in parts by weight: 25-50 parts of diisocyanate, 30-40 parts of polyol, 3-15 parts of chain extender, 0.5-15 parts of reinforcing agent, 0.5-3 parts of catalyst, 1-3 parts of ultraviolet light absorber, 0.5-3 parts of antioxidant and 0.5-2 parts of lubricant.
2. The thermoplastic polyurethane elastomer according to claim 1, characterized in that The polyol is any one of tetrahydrofuran-propylene oxide copolymer glycol and polytetramethylene ether glycol; The chain extender is any one of 1,3-propylene glycol, 1,4-butanediol, 4,4′-xylene methane-5-maleimide, and hydroquinone bis(hydroxyethyl) ether, or a mixture of several thereof; The reinforcing agent is an active substance having hydroxyl groups on the surface or capable of forming more hydrogen bonds; The catalyst is any one of dibutyltin dilaurate, stannous oleate, and stannous octoate; The ultraviolet light absorber is any one of UV-327, UV-328, UV-329, UV-360, UV-571, UV-1130, and UV-1300, or a mixture of several thereof; The antioxidant is any one of butyl para-oxybenzoate and M-benzene; The lubricant is any one of calcium stearate, zinc stearate, pentaerythritol stearate, and oleic acid amide, or a mixture of several of them.
3. The thermoplastic polyurethane elastomer according to claim 2, characterized in that The reinforcing agent is any one of silicon dioxide, titanium dioxide, graphene oxide, molecular sieve, and montmorillonite, or a mixture of several of them.
4. A method for preparing a thermoplastic polyurethane elastomer with high-efficiency thermal welding performance, characterized in that: The raw materials are mixed, and a molten mixed colloid is obtained by a twin-screw extruder, and the molten mixed colloid is cast and then cooled and molded by a cooling roller.
5. The method for preparing a thermoplastic polyurethane elastomer according to claim 4, characterized in that: The extrusion temperature of the twin-screw extruder is 170-230°C, the extrusion pressure is 9-23MPa, and the rotation speed is 20-120rpm; The cooling roller temperature is 10-55°C.