A high-strength water-swellable polyurethane elastomer and a method for producing the same

Abstract

This invention relates to the field of polymer materials technology, and proposes a high-strength water-swellable polyurethane elastomer and its preparation method. The raw materials of the high-strength water-swellable polyurethane elastomer include component A and component B in a mass ratio of 100:55~60; component A includes a polyurethane prepolymer; component B includes allyl polyoxyethylene ether, polyether polyol, and chain extender; the raw materials of the polyurethane prepolymer include isocyanate and polyether polyol. This technical solution solves the problems of insufficient mechanical properties and low expansion ratio of water-swellable polyurethane elastomers in related technologies.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a high-strength water-swellable polyurethane elastomer and its preparation method. Background Technology

[0002] Water-swellable polyurethane elastomers possess both elastic sealing and water-swelling properties. Typical water-swellable polyurethane elastomers consist of soft segments of hydrophilic polyether polyols and hard segments such as diisocyanates and chain extenders. The main reason for water swelling is the formation of hydrogen bonds between the methylene ether in the hydrophilic polyether and water, which can bind a large number of water molecules. Water-swellable polyurethane elastomers have seen rapid development in recent years and are primarily used in sealing, waterproofing, and water-stopping materials.

[0003] There are also some drawbacks in the application of water-swellable polyurethane elastomers, such as embrittlement during the water-swelling process, decreased mechanical properties, and the need to increase the expansion ratio. To solve these problems, a new type of high-strength water-swellable polyurethane elastomer is needed. Summary of the Invention

[0004] This invention proposes a high-strength water-swellable polyurethane elastomer and its preparation method, which solves the problems of insufficient mechanical properties and low expansion ratio of water-swellable polyurethane elastomers in related technologies.

[0005] The technical solution of the present invention is as follows: This invention proposes a high-strength water-swellable polyurethane elastomer, the raw materials of which include component A and component B in a mass ratio of 100:55~60; Component A includes a polyurethane prepolymer; the raw materials for component B include allyl polyoxyethylene ether polyethers, polyether polyols, and chain extenders.

[0006] As a further technical solution, the raw materials of the polyurethane prepolymer include isocyanate and polyether polyol.

[0007] As a further technical solution, the mass ratio of isocyanate to polyether polyol is 100~110:20~25; The mass ratio of the allyl polyoxyethylene ether polyether, polyether polyol and chain extender is 30~35:18:7~7.5.

[0008] As a further technical solution, the polyether polyols in the raw materials of the polyurethane prepolymer and component B each independently include polyethylene glycol.

[0009] As a further technical solution, the polyethylene glycol includes at least one of PEG-600, PEG-3000, and PEG-4000; Preferably, in the raw materials of the polyurethane prepolymer, polyethylene glycol includes PEG-3000 and PEG-4000; in the raw materials of component B, polyethylene glycol includes PEG-600. More preferably, in the raw materials of the polyurethane prepolymer, the polyethylene glycol includes PEG-3000 and PEG-4000 in a mass ratio of 50~60:50~55.

[0010] As a further technical solution, the allyl polyoxyethylene ether polyether includes at least one of allyl polyoxyethylene ether, isopentenyl polyoxyethylene ether, and methyl allyl polyoxyethylene ether.

[0011] As a further technical solution, the molecular weight of the allyl polyoxyethylene ether is 1000~2000.

[0012] As a further technical solution, the chain extender includes MOCA.

[0013] As a further technical solution, the method for preparing the polyurethane prepolymer includes the following steps: Polyether polyol and isocyanate were reacted at 80-85℃ for 2 hours to obtain polyurethane prepolymer.

[0014] As a further technical solution, the polyether polyol was dehydrated before the reaction.

[0015] As a further technical solution, the temperature of the dehydration treatment is 100~130℃ and the time is 2~2.5.

[0016] This invention also proposes a method for preparing a high-strength water-swellable polyurethane elastomer, comprising the following steps: Components A and B are mixed and reacted to obtain a water-swellable polyurethane elastomer.

[0017] As a further technical solution, the reaction temperature is 120~130℃ and the time is 1h.

[0018] The working principle and beneficial effects of this invention are as follows: In this invention, allyl polyoxyethylene ether is used as the raw material for component B, which reacts with component A to introduce allyl polyoxyethylene ether. In addition to the addition polymerization reaction of isocyanate and hydroxyl groups, a free radical addition reaction of double bonds also occurs during the process. At the same time, the chain extension reaction of polyurethane and the free radical polymerization reaction of allyl polyoxyethylene ether are completed, which increases the content of hydrophilic segments and the crosslinking of polymer molecules, and significantly improves the mechanical properties and expansion ratio of water-swellable polyurethane elastomer. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1 A method for preparing a high-strength, water-swellable polyurethane elastomer includes the following steps: Preparation of S1 and A components: 50 g of PEG-3000 and 50 g of PEG-4000 were added to a three-necked flask and heated to dissolve. The temperature was raised to 100°C and dehydrated under vacuum for 2.5 hours. Then the temperature was lowered to 50°C and 20 g of TDI was added. The mixture was reacted at 80°C for 2 hours to obtain component A. Preparation of S2 and B components: 7.5 g MOCA, 18 g PEG-600 and 30 g APEG-2000 were heated and mixed evenly to obtain component B; S3. Mix 100g of component A and 55.5g of component B evenly and react at 120℃ for 1 hour to simultaneously complete the chain extension reaction of polyurethane and the free radical polymerization reaction of allyl polyoxyethylene ether, thereby obtaining a high-strength water-swellable polyurethane elastomer.

[0021] Example 2 A method for preparing a high-strength, water-swellable polyurethane elastomer includes the following steps: Preparation of S1 and A components: 60 g of PEG-3000 and 50 g of PEG-4000 were added to a three-necked flask and heated to dissolve. The temperature was raised to 130°C and dehydrated under vacuum for 2 hours. Then the temperature was lowered to 60°C and 25 g of TDI was added. The reaction was carried out at 85°C for 2 hours to obtain component A. Preparation of S2 and B components: 7 g MOCA, 18 g PEG-600 and 35 g APEG-2000 were heated and mixed evenly to obtain component B; S3. Mix 100g of component A and 59g of component B evenly and react at 130℃ for 1 hour to simultaneously complete the chain extension reaction of polyurethane and the free radical polymerization reaction of allyl polyoxyethylene ether, thereby obtaining a high-strength water-swellable polyurethane elastomer.

[0022] Example 3 A method for preparing a high-strength, water-swellable polyurethane elastomer includes the following steps: Preparation of S1 and A components: 50 g of PEG-3000 and 55 g of PEG-4000 were added to a three-necked flask and heated to dissolve. The temperature was raised to 120°C and dehydrated under vacuum for 2.2 hours. Then the temperature was lowered to 55°C and 22 g of TDI was added. The reaction was carried out at 83°C for 2 hours to obtain component A. Preparation of S2 and B components: 7 g MOCA, 18 g PEG-600 and 30 g APEG-2000 were heated and mixed evenly to obtain component B; S3. Mix 100g of component A and 56g of component B evenly and react at 125℃ for 1 hour to simultaneously complete the chain extension reaction of polyurethane and the free radical polymerization reaction of allyl polyoxyethylene ether, thereby obtaining a high-strength water-swellable polyurethane elastomer.

[0023] Comparative Example 1 A method for preparing water-swellable polyurethane elastomer includes the following steps: Preparation of S1 and A components: 60 g of PEG-3000 and 50 g of PEG-4000 were added to a three-necked flask and heated to dissolve. The temperature was raised to 130°C and dehydrated under vacuum for 2 hours. Then the temperature was lowered to 60°C and 25 g of TDI was added. The reaction was carried out at 85°C for 2 hours to obtain component A. Preparation of S2 and B components: 7 g of MOCA, 18 g of PEG-600 and 17.5 g of PEG-2000 were heated and mixed evenly to obtain component B; S3. Mix 100g of component A and 59g of component B evenly, and react at 130℃ for 1 hour to complete the chain extension reaction of polyurethane, and obtain water-swellable polyurethane elastomer.

[0024] Experimental Example The mechanical properties and expansion ratio of the high-strength water-swellable polyurethane elastomers prepared in the examples and comparative examples were tested respectively: Mechanical properties: The tensile strength and elongation of water-swellable polyurethane elastomer were tested according to GB / T 528-2009 "Determination of tensile properties of vulcanized rubber or thermoplastic rubber". Swelling ratio: According to Test Method I in Appendix A of GB / T 18173.3-2014 "Polymer Waterproof Materials Part 3: Water-Swellable Rubber", the volume expansion rate of water-swellable polyurethane elastomer in pure water is tested. The results are shown in Table 1 below.

[0025] Table 1 Performance Test Results

[0026] Compared with the comparative example, the water-swellable polyurethane elastomer prepared in the embodiments of the present invention has higher tensile strength, elongation and volume expansion rate, indicating that using allyl polyoxyethylene ether polyether as the raw material of component B significantly improves the mechanical properties and expansion ratio of the water-swellable polyurethane elastomer.

[0027] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-strength, water-swellable polyurethane elastomer, characterized in that, The raw materials include component A and component B in a mass ratio of 100:55~60; Component A includes a polyurethane prepolymer; the raw materials for component B include allyl polyoxyethylene ether polyethers, polyether polyols, and chain extenders.

2. The high-strength water-swellable polyurethane elastomer according to claim 1, characterized in that, The raw materials for the polyurethane prepolymer include isocyanate and polyether polyol.

3. The high-strength water-swellable polyurethane elastomer according to claim 2, characterized in that, The mass ratio of isocyanate to polyether polyol is 100~110:20~25; The mass ratio of the allyl polyoxyethylene ether polyether, polyether polyol and chain extender is 30~35:18:7~7.

5.

4. The high-strength water-swellable polyurethane elastomer according to claim 2, characterized in that, The polyether polyols in the raw materials of the polyurethane prepolymer and component B each independently include polyethylene glycol.

5. The high-strength water-swellable polyurethane elastomer according to claim 4, characterized in that, The polyethylene glycol includes at least one of PEG-600, PEG-3000, and PEG-4000; Preferably, in the raw materials of the polyurethane prepolymer, polyethylene glycol includes PEG-3000 and PEG-4000; in the raw materials of component B, polyethylene glycol includes PEG-600. More preferably, in the raw materials of the polyurethane prepolymer, the polyethylene glycol includes PEG-3000 and PEG-4000 in a mass ratio of 50~60:50~55.

6. The high-strength water-swellable polyurethane elastomer according to claim 1, characterized in that, The allyl polyoxyethylene ether polyethers include at least one of allyl polyoxyethylene ether, isopentenyl polyoxyethylene ether, and methyl allyl polyoxyethylene ether.

7. The high-strength water-swellable polyurethane elastomer according to claim 1, characterized in that, The molecular weight of the allyl polyoxyethylene ether polyether is 1000~2000.

8. The high-strength water-swellable polyurethane elastomer according to claim 1, characterized in that, The chain extender includes MOCA.

9. A high-strength water-swellable polyurethane elastomer according to claim 1, characterized in that, The method for preparing the polyurethane prepolymer includes the following steps: Polyether polyol and isocyanate were reacted at 80-85℃ for 2 hours to obtain polyurethane prepolymer.

10. A method for preparing a high-strength water-swellable polyurethane elastomer, used to prepare the high-strength water-swellable polyurethane elastomer according to any one of claims 1 to 9, characterized in that, Includes the following steps: Components A and B are mixed and reacted to obtain a water-swellable polyurethane elastomer.

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