阅读说明：本技术 一种pu冲浪板板芯及其制备方法 (PU surfboard core and preparation method thereof ) 是由 李建民 袁桂芳 汪昌盛 于 2020-08-04 设计创作，主要内容包括：本发明公开了一种PU冲浪板板芯及其制备方法,由以下质量比例的原料制成：聚醚多元醇80-100、二苯基甲烷二异氰酸酯150-200、2-(2-羟基-5-叔辛基苯基)苯并三唑20-25、玻璃纤维10-15、发泡剂3-5、泡沫稳定剂1-3、催化剂2-4、阻燃剂6-8。本发明PU冲浪板板芯,结合常规PU制备工艺的基础上,通过对聚氨酯发泡材料的连续增强改性,以提高其作为冲浪板板芯的物理性能,通过与聚氨酯界面间形成机械能协同传递作用来间接提高聚氨酯材料的力学性能,同时结合有机小分子对聚氨酯结构上的增强,大大提高了材料的整体性能,同时玻璃纤维的质轻特性,能有效减少材料质量,更利于其作为冲浪板提升浮力,增强人的冲浪体验。(The invention discloses a PU surfboard core and a preparation method thereof, wherein the core is prepared from the following raw materials in percentage by mass: 80-100 parts of polyether polyol, 150 parts of diphenylmethane diisocyanate, 20-25 parts of 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 10-15 parts of glass fiber, 3-5 parts of foaming agent, 1-3 parts of foam stabilizer, 2-4 parts of catalyst and 6-8 parts of flame retardant. The PU surfboard core disclosed by the invention is combined with the conventional PU preparation process, the physical property of the PU surfboard core is improved by continuously enhancing and modifying the polyurethane foaming material, the mechanical property of the polyurethane material is indirectly improved by forming a mechanical energy synergistic transfer effect with a polyurethane interface, and meanwhile, the organic micromolecules are combined to enhance the polyurethane structure, so that the overall property of the material is greatly improved, meanwhile, the light weight characteristic of the glass fiber can effectively reduce the material quality, the PU surfboard core is more beneficial to serving as a surfboard to improve the buoyancy, and the surfing experience of people is enhanced.)

1. The PU surfboard core is characterized by being prepared from the following raw materials in parts by mass: 80-100 parts of polyether polyol, 150 parts of diphenylmethane diisocyanate, 20-25 parts of 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 10-15 parts of glass fiber, 3-5 parts of foaming agent, 1-3 parts of foam stabilizer, 2-4 parts of catalyst and 6-8 parts of flame retardant.

2. The PU surfboard core according to claim 1, characterized in that it is made of the following raw materials in mass ratio: polyether polyol 90, diphenylmethane diisocyanate 180, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole 22, glass fiber 13, foaming agent 4, foam stabilizer 2, catalyst 3 and flame retardant 7.

3. The PU surfboard core of claim 1, wherein the blowing agent is any one of monofluorodichloroethane, cyclopentane.

4. The PU surfboard core of claim 1, wherein the flame retardant is an intumescent flame retardant.

5. A method of making the PU surfboard core of any one of claims 1-4, comprising the steps of:

(1) mixing polyether polyol, a foaming agent, a foam stabilizer, a catalyst and a flame retardant, adding the mixture into a reaction tank, fully and uniformly mixing the mixture under high-speed electric stirring, introducing nitrogen atmosphere, adding diphenylmethane diisocyanate under the stirring state, continuously stirring and reacting for 30-60 minutes until the color of the mixed solution is nearly whitish, and taking out the mixed solution for vacuum defoaming for later use;

(2) dissolving the product in 10-20 times volume of N, N-dimethylformamide and tetrahydrofuran in a volume ratio of 1: 1, heating at 90-100 ℃ for 40-60 minutes, cooling to room temperature, adding 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, mechanically stirring and ultrasonically dispersing to obtain uniform dispersion liquid;

(3) taking a mould according to the specification, carrying out mould release agent treatment, paving glass fibers in the mould, pouring the dispersion liquid obtained in the step (2) into the mould, and curing for 2-4 hours at 80-90 ℃ after vacuum defoaming;

(4) and (3) feeding the material obtained in the step (3) into a foaming mold, heating the foaming mold by steam at the temperature of 150-.

6. The method for preparing the PU surfboard core according to claim 5, wherein the ultrasonic dispersion in the step 2 is controlled at a frequency of 35-45KHz, at a temperature of 30-40 ℃ and for a time of 25-35 minutes.

7. The method for preparing the PU surfboard core according to claim 5, wherein the glass fiber is uniformly laid in the same direction in the step 3, and dried at 100-120 ℃ for removing water for 1-3 hours after completion.

8. The method for preparing the PU surfboard core according to claim 5, wherein the vacuum is applied every 4-8 hours during the vacuum drying in the step 4, and the vacuum is applied to-0.09 MPa.

Technical Field

The invention belongs to the technical field of surfboard processing and production, and particularly relates to a PU surfboard core and a preparation method thereof.

Background

Surfing is extreme sports powered by sea waves, because a surfboard is light and convenient to carry, can be used for fiercely stimulating wave chasing impact in heavy waves, can lie on the surfboard to float on water in small waves, and can enjoy leisure fun of natural fluctuation, and is very stimulating and enjoying, the surfing is one of very common interesting sports, the originally used surfboard is about 5 meters long and weighs 50-60 kilograms, and after the world war II, a foam plastic board appears, and the shape of the board is also improved. With the improvement of living standard, people have more and more demands on surfboards.

The prior surfboard technology adopts a method of repeatedly laminating and bonding a plurality of materials for production and processing, the materials and the technology of the board core are different, the produced product standards are different, the prior board core looks firm in the aspect of the durability of the board core, but the board is easy to break when the surfboard goes out and waves cross, and the service life is short. The polyurethane material is one of the most used composite matrix resins in the composite material technology, has the properties of high wear resistance, tear resistance, vibration reduction, toughness, high fatigue strength and the like, and meets the requirements of the core material of the surfing board, so that the polyurethane material is an excellent material for manufacturing the core of the surfing board.

Disclosure of Invention

The invention aims to make up for the defects of the prior art and provides a PU surfboard core and a preparation method thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

a PU surfboard core is prepared from the following raw materials in parts by mass: 80-100 parts of polyether polyol, 150 parts of diphenylmethane diisocyanate, 20-25 parts of 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 10-15 parts of glass fiber, 3-5 parts of foaming agent, 1-3 parts of foam stabilizer, 2-4 parts of catalyst and 6-8 parts of flame retardant.

Preferably, the PU surfboard core is prepared from the following raw materials in percentage by mass: polyether polyol 90, diphenylmethane diisocyanate 180, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole 22, glass fiber 13, foaming agent 4, foam stabilizer 2, catalyst 3 and flame retardant 7.

Further, the foaming agent is any one of monofluorodichloroethane and cyclopentane.

Further, the flame retardant is an intumescent flame retardant.

The preparation method of the PU surfboard core comprises the following steps:

(1) mixing polyether polyol, a foaming agent, a foam stabilizer, a catalyst and a flame retardant, adding the mixture into a reaction tank, fully and uniformly mixing the mixture under high-speed electric stirring, introducing nitrogen atmosphere, adding diphenylmethane diisocyanate under the stirring state, continuously stirring and reacting for 30-60 minutes until the color of the mixed solution is nearly whitish, and taking out the mixed solution for vacuum defoaming for later use;

(2) dissolving the product in 10-20 times volume of N, N-dimethylformamide and tetrahydrofuran in a volume ratio of 1: 1, heating at 90-100 ℃ for 40-60 minutes, cooling to room temperature, adding 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, mechanically stirring and ultrasonically dispersing to obtain uniform dispersion liquid;

(3) taking a mould according to the specification, carrying out mould release agent treatment, paving glass fibers in the mould, pouring the dispersion liquid obtained in the step (2) into the mould, and curing for 2-4 hours at 80-90 ℃ after vacuum defoaming;

(4) and (3) feeding the material obtained in the step (3) into a foaming mold, heating the foaming mold by steam at the temperature of 150-.

Further, the ultrasonic dispersion in the step 2 is controlled at 35-45KHz, 30-40 ℃ and 25-35 minutes.

Further, the glass fiber is uniformly laid in the same direction in the step 3, and is dried and dehydrated at the temperature of 100-120 ℃ for 1-3 hours after the completion.

Further, in the step 4, vacuum pumping is performed once every 4 to 8 hours during vacuum drying, and the vacuum pumping is performed until the pressure is reduced to-0.09 MPa.

The invention has the advantages that:

the PU surfboard core disclosed by the invention is combined with the conventional PU preparation process, and the physical property of the PU surfboard core as a surfboard core is improved by continuously enhancing and modifying the polyurethane foaming material. One is that in the preparation process of the polyurethane prepolymer, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole is introduced into polyurethane by taking N, N-dimethylformamide and tetrahydrofuran as solvents and is used as a functional organic micromolecule, the triazole ring on the benzotriazole easily forms an intramolecular hydrogen bond with ortho-position hydroxyl on a benzene ring of the polyurethane to form a hexahydric ring structure with lower potential energy and relative stability, and simultaneously does not participate in the hydrogen bond combination with the polyurethane, so that the stress among polyurethane molecular chains is weakened, such as van der Waals force, hydrogen bond action and the like, and further plays a role in enhancing, the tensile stress of the polyurethane material is improved, and the polyurethane material is suitable for being used as a surfing board core material and is not easy to break under the impact of wave water; secondly, in the polyurethane forming process, the glass fiber material is added into the mold, fibers can be uniformly distributed in the polyurethane after the polyurethane is cured and are tightly wrapped by the polyurethane, the glass fiber has excellent tensile strength, bending strength and impact toughness, the mechanical property of the polyurethane material can be indirectly improved by forming a mechanical energy synergistic transfer effect with a polyurethane interface, and meanwhile, the organic micromolecules are combined to reinforce the polyurethane structure, so that the overall performance of the material is greatly improved, meanwhile, the light weight characteristic of the glass fiber can effectively reduce the material quality, the glass fiber is more beneficial to serving as a surfboard to improve the buoyancy, and the surfing experience of people is enhanced.

Detailed Description

The technical scheme of the invention is further explained by combining the specific examples as follows: