Polyurethane foam for integral bathroom and preparation method thereof

Abstract

The invention discloses polyurethane foam for a whole bathroom and a preparation method of the polyurethane foam, melamine polyol, polyether polyol a and polyether polyol b in the foam form a polyether polyol package, the molecular structure of the polyether polyol a is regular and symmetrical, and the polyether polyol a has high hydroxyl, lower viscosity and milder reaction; the initial viscosity of foaming reaction materials and the viscosity during foaming reaction are improved, the fluidity is good, filling is uniform, deformation or cavities are not prone to occurring, and the density difference is small; the melamine polyol and the polyether polyol are crosslinked, so that the mechanical strength is high, and the compression performance is good; the polyether polyol b is good in wetting property, so that the mixing and reaction uniformity of the polyether polyol is promoted; the catalyst is combined to balance the flowability and stability of the system and control the generation and completeness of the reaction, and the silicone oil promotes the dispersion stability of the catalyst in the system, improves the foam uniformity and surface smoothness, reduces the density difference, improves the high temperature resistance and high humidity resistance, prevents aging and prolongs the service life.

Description

Technical Field

[0001] The invention relates to polyurethane foam, in particular to polyurethane foam for integral bathroom and a preparation method thereof. Background Art

[0002] The whole bathroom is an independent sanitary unit formed by an integrated waterproof chassis, wall panels, and top panels, and equipped with various functional sanitary ware. It can be customized according to the size of the house and personal preferences. It is easy to install, has high construction efficiency, low construction cost, no odor, complete functions, strong and durable, heat insulation, fire safety, environmental protection and other characteristics. It is chosen by more and more families, and is also widely used in apartments, economy hotels, temporary medical places and real estate companies. In the preparation process of the whole bathroom, polyurethane foam is filled in a mold with tiles and foamed to form the whole bathroom wall panel. The existing polyurethane foam has poor fluidity and poor affinity with tiles. The bulk density distribution on the wall panel is uneven and it is easy to have voids, which affects the load-bearing performance of the wall panel. The functional sanitary ware installed in the position with voids is easy to crack or even fall because it cannot bear its weight, affecting the safe use of the whole bathroom. The fluidity is closely related to the stability of the polyurethane foam. The foam with better fluidity has a fast filling speed, better filling uniformity, and is not easy to have inadequate filling. However, if the fluidity is too high, the initial viscosity of the foam is too low, leakage is likely to occur, and the curing rate is reduced. It also affects the density and strength of the molded polyurethane foam and the firmness of the overall bathroom wall panels. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to improve the fluidity of the foam without affecting the density and strength of the polyurethane foam, thereby improving the filling uniformity of the foam on the wall panel and reducing the density difference of the foam, and providing a polyurethane foam for an integrated bathroom; Another purpose of the present invention is to provide a method for preparing the above-mentioned integrated bathroom wall panel.

[0004] Technical solution: The polyurethane foam for integrated bathroom of the present invention comprises component A and component B in a mass ratio of 1:1 to 1.4; in terms of weight, component A comprises: 10 to 25 parts of melamine polyol, 25 to 45 parts of polyether polyol a, and 25 to 45 parts of polyether polyol b. 18-30 parts, 15-27.5 parts of flame retardant, 2.5-5 parts of catalyst, 1-2 parts of silicone oil, 1-1.5 parts of deionized water; component B is isocyanate; the functionality of the melamine polyol is 2, the hydroxyl value is 200-230 mgKOH / g, and the viscosity is 650-850 mPa·s; the functionality of the polyether polyol a is 4, the hydroxyl value is 435-570 mgKOH / g, and the viscosity is 2400-5500 mPa·s; the functionality of the polyether polyol b is 2, the hydroxyl value is 281-375 mgKOH / g, and the viscosity is 20-45 mPa·s.

[0005] Furthermore, the melamine polyol is selected from EDS-5083L-KD. The melamine polyol has a highly cross-linked and stable triazine ring structure, which improves the cross-linking strength of the foam system, so that the prepared polyurethane for the integral bathroom wall panels has good mechanical strength and compression performance, and at the same time has good heat resistance, water resistance and flame retardancy, thereby improving the service life of the integral bathroom wall panels.

[0006] Furthermore, the polyether polyol a is selected from at least one of POLYOL PEP 450 and POLYOL PEP 550; and the polyether polyol b is selected from at least one of PEG300 and PEG400.

[0007] Melamine polyol, polyether polyol a and polyether polyol b form a polyether polyol package: polyether polyol a is pentaerythritol polyether polyol, which contains four secondary hydroxyl groups, has a relatively regular and symmetrical molecular structure, has high hydroxyl groups, low viscosity, and relatively mild reaction. It has good crosslinking with isocyanate, promotes the mixing rate and uniformity of the reaction system materials, is conducive to balancing the foaming reaction and the gel reaction, improves the initial viscosity of the foaming reaction materials and the viscosity during the foaming reaction, and has good fluidity of the foam, ensuring that the foam can be filled evenly in the mold, is not easy to deform, and will not have voids. , thereby improving the uniformity of the foam and reducing the density difference; polyether polyol b is polyoxyethylene polyol, and the structure of ethylene glycol in the molecular chain determines that it has better wettability and water solubility, further improving the viscosity, fluidity and stability of the system, making the melamine polyol and polyether polyol a in the system more evenly dispersed, and the uniformity of the cross-linking reaction between the two and isocyanate is good, taking into account the fluidity during foam generation, the mechanical strength and uniformity after the foam is generated, further ensuring the sufficiency and uniformity of the filling in the bathroom wall panels, and ensuring the uniformity of the compression strength and density of the foam.

[0008] Furthermore, the flame retardant is selected from at least one of phosphate esters and halogenated phosphate esters; the flame retardant is selected from at least one of triethyl phosphate and tri(1-chloro-2-propyl) phosphate. TEP triethyl phosphate is a flame retardant with low viscosity and has a certain catalytic effect on the combination of polyether polyol packages; TCPP tri(1-chloro-2-propyl) phosphate is a flame retardant and improves the flexibility of polyether polyols to further promote their combination effect. The combination of the two improves the flame retardant effect and the mixing uniformity of the polyether polyol package.

[0009] Furthermore, the component B is selected from at least one of M20S or PM-200, M20S is a compound containing a specific proportion of isocyanate and has excellent curing performance and stability, PM-200 has higher functionality and fluidity, and both have higher crosslinking reaction activity with polyether polyols and better promote foam generation.

[0010] Furthermore, the catalyst is selected from at least two of DMEA, PC8, A33, PC41, and TMR2. DMEA is a low-odor reaction-type catalyst that can improve the environmental performance of the overall bathroom; PC-41 has excellent foaming and gelling capabilities; PC8 is a required catalyst, and its low viscosity characteristics are conducive to improving the fluidity of the foam in the early stage and during the reaction, while balancing the foaming reaction and the gelling reaction to adjust the time interval from milky white to gel, and further improve the fluidity of the material; TMR2, as a mild high-temperature catalyst, promotes the reaction between isocyanate and polyether polyol, maintains good fluidity of the system, and promotes the complete reaction, so that the plate is not easy to deform; A33, as a highly active tertiary amine catalyst, promotes the cross-linking of isocyanate and polyether polyol in the gelling reaction, and increases the mechanical strength of the foam. Adjusting the appropriate ratio of the catalyst, balancing the fluidity and stability of the system, controlling the occurrence and completeness of the reaction, can more accurately adjust the time interval from milky white to gel, improve the uniformity of the foam and the smoothness of the surface, and reduce the density difference.

[0011] Furthermore, the silicone oil is selected from at least one of AK8805, B8545 or DC193. Silicone oil is used as a surfactant and auxiliary foaming agent in combination with the catalyst. Its lubricating property and water solubility improve the dispersion property of the catalyst in the system, can reduce the surface tension and viscosity of the polyurethane foam, further promote the mixing uniformity of the polyol component, and then promote the cross-linking reaction of isocyanate and polyether polyol, improve the fluidity of the foam and the uniformity of the reaction, and at the same time enhance the stability and uniformity of the foaming during foaming, control the size and distribution of the pores, and avoid the phenomenon of rupture of the foam wall or loose structure.

[0012] The present invention also provides a method for preparing an integral bathroom wall panel using the polyurethane foam, comprising the following steps:

[0013] (1) Component A is mixed evenly and placed in a sealed container;

[0014] (2) Component B, packed in a sealed container;

[0015] (3) Components A and B are mixed evenly in a high-pressure casting machine according to the mass ratio and then injected into a mold with tiles at the bottom. After the mold is closed, the components are foamed and matured to obtain an integrated bathroom wall panel.

[0016] Furthermore, in step (3), the mixing temperature of component A and component B is 15° C.-25° C., and the mixing pressure is 60 bar-120 bar.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: 1. Melamine polyol, polyether polyol a and polyether polyol b form a polyether polyol package: polyether polyol a is pentaerythritol, the molecular structure of polyether polyol is relatively regular and symmetrical, with high hydroxyl group, low viscosity and relatively mild reaction, which improves the initial viscosity of the foaming reaction material and the viscosity during the foaming reaction, and the fluidity of the foam is good, ensuring that the foam can be filled evenly in the mold, with a small density difference, not easy to deform and no voids; melamine polyol has a high cross-linking structure, which improves the cross-linking strength with polyether polyol, so that the prepared polyurethane for the integral bathroom wall panel has good mechanical strength and compression performance, and at the same time has good heat resistance, water resistance and flame retardancy, thereby improving the service life of the integral bathroom wall panel; polyether polyol b is polyethylene oxide polyol, and the structure of ethylene glycol in the molecular chain determines its It has better wettability and water solubility, further improves the viscosity, fluidity and stability of the system, makes the melamine polyol and polyether polyol a in the system more evenly dispersed, and the uniformity of the cross-linking reaction between the two and isocyanate is good, taking into account the fluidity during foam generation, the mechanical strength and uniformity after foam generation; 2. The catalyst is used in combination to balance the fluidity and stability of the system, control the occurrence and completeness of the reaction, and the silicone oil further promotes the dispersion stability of the catalyst in the system, avoids the phenomenon of foam wall rupture or loose structure, improves the foam uniformity and surface smoothness, reduces the density difference, improves the bearing capacity of the wall panel, ensures the installation strength of the bathroom, and improves the service life of the overall bathroom; 3. Silicone oil forms a protective layer on the surface of the foam pores, improves the high temperature and humidity resistance and oxidation resistance of the polyurethane foam, prevents foam aging, and further extends the service life of the overall bathroom. DETAILED DESCRIPTION

[0018] The technical scheme of the present invention is further described below in conjunction with specific embodiments. The reagents used in the present invention are all commercially available, as shown in Table 1. The deionized water used as the foaming agent is homemade and meets the quality specifications of grade 3 water in GB / T 6682-2016.

[0019] Table 1 List of raw materials

[0020]

[0021] Table 2 shows the components and proportions (parts by weight) of Examples 1 to 7 and Comparative Examples 1 to 2, and blanks indicate that the component is not added. Different from Examples 1 to 7, polyether polyol c is used to replace polyether polyol a and polyether polyol b in component A of Comparative Examples 1 and 2, and other components are adjusted for suitability.

[0022] Table 2 Proportions of different components in each embodiment and comparative example

[0023]

[0024] The preparation method of the polyurethane spray foam material of the above embodiment and comparative example comprises the following steps:

[0025] (1) Weigh and mix component A uniformly by weight and place in a sealed container;

[0026] (2) Weigh component B and place it in a sealed container;

[0027] (3) Components A and B are mixed uniformly in a high-pressure pouring machine according to the mass ratio, the mixing temperature is 15°C-25°C, and the mixing pressure is 60bar-120bar; then injected into a mold with tiles at the bottom, and foamed and matured after the mold is closed to obtain an integrated bathroom wall panel.

[0028] The polyurethane spray foam materials prepared in the above examples and comparative examples were tested for density, fluidity and compressive strength (GB / T 8813-2008), as shown in Table 3:

[0029] Density difference (GB / T 6343-2009) test: Randomly select 9 samples from the wallboard to test the density, and take the maximum value as D max , the minimum value is D min , density difference = D max -D min .

[0030] Flow index: Place component A and component B in a flowability tester according to the formula ratio. The foam is vertically foamed in the flowability tester until it is solidified and formed. The foam growth height (cm) and foam mass (g) are measured. The test is repeated 3 times in parallel and the average value is taken. Flow coefficient = foam growth height / foam mass.

[0031] Table 3 Performance test results of various embodiments and comparative examples

[0032]

[0033] Compared with Comparative Examples 1 and 2, Examples 1-7 use melamine polyol, polyether polyol a and polyether polyol b to form a polyether polyol package. The molecular structure of pentaerythritol polyether polyol is relatively regular and relatively mild when participating in the reaction. The initial viscosity of the foaming reaction material and the viscosity during the foaming reaction are improved, and the fluidity of the foam is good. The excellent fluidity ensures that the foam can be filled evenly in the mold, the density difference is small, and it is not easy to deform. In Comparative Examples 1 and 2, polyether polyol a and polyether polyol b are not added to component A, which affects the viscosity of the system and the viscosity when reacting with isocyanate, affects the fluidity of the system, and then affects the filling performance of the foam in the mold, affects the uniformity of the polyurethane foam, and has a large density difference. Comparative Examples 1-7 have a compression strength. The more melamine polyol is used, the more cross-linking strength with polyether polyol is improved, so that the mechanical strength of the polyurethane prepared for the integral bathroom wallboard is high and the compression performance is improved. The fluidity of Example 1 is small, indicating that excessive use of melamine polyol will reduce the fluidity of the system.

[0034] In Examples 1-7, Examples 3 and 6 have greater compression strength and higher fluidity, mainly because PC8 is used as a required catalyst, and its low viscosity is conducive to improving the fluidity of the foam in the early stage and during the reaction, while balancing the foaming reaction and the gel reaction to adjust the time interval from milky white to gel, and further improving the fluidity of the material; A33, as a highly active tertiary amine catalyst, promotes the cross-linking of isocyanate and polyether polyol in the gel reaction, increases the mechanical strength of the foam, adjusts the appropriate ratio of PC8, TMR2 and A33, balances the fluidity and stability of the system, controls the occurrence and completeness of the reaction, can more accurately adjust the time interval from milky white to gel, improves the uniformity of the foam and the smoothness of the surface, and reduces the density difference. However, the density difference of Example 6 is slightly larger than that of Example 3, mainly because silicone oil is used as a surfactant and auxiliary foaming agent with a catalyst, and the high affinity and wetting performance of B8545 is matched with a catalyst PC8 with good fluidity, which can improve the dispersion strength of the catalyst PC8 in the system, enhance the stability and uniformity of the foam, control the size and distribution of the pores, and reduce the density difference of the foam.

Claims

1. A polyurethane foam for overall bathroom, characterized in that: The invention comprises component A and component B in a mass ratio of 1:1-1.4; in terms of weight parts, component A comprises: 10-25 parts of melamine polyol, 25-45 parts of polyether polyol a, 18-30 parts of polyether polyol b, 15-27.5 parts of flame retardant, 2.5-5 parts of catalyst, 1-2 parts of silicone oil and 1-1.5 parts of deionized water; component B is isocyanate; the functionality of the melamine polyol is 2, the hydroxyl value is 200-230 mgKOH / g and the viscosity is 650-850 mPa·s; the functionality of the polyether polyol a is 4, the hydroxyl value is 435-570 mgKOH / g and the viscosity is 2400-5500 mPa·s; the functionality of the polyether polyol b is 2, the hydroxyl value is 281-375 mgKOH / g and the viscosity is 20-45 mPa·s.

2. The polyurethane foam for overall bathroom use according to claim 1, characterized in that: The melamine polyol is selected from EDS-5083L-KD.

3. The polyurethane foam for overall bathroom use according to claim 1, characterized in that: The polyether polyol a is selected from at least one of POLYOLPEP450 and POLYOLPEP 550.

4. The polyurethane foam for integrated bathroom according to claim 1, characterized in that: The polyether polyol b is selected from at least one of PEG300 and PEG400.

5. The polyurethane foam for integrated bathroom according to claim 1, characterized in that: The flame retardant is selected from at least one of phosphate ester and halogenated phosphate ester flame retardants; the flame retardant is selected from at least one of tris(1-chloro-2-propyl) phosphate and triethyl phosphate.

6. The polyurethane foam for integrated bathroom according to claim 1, characterized in that: The component B is selected from at least one of M20S or PM-200.

7. The polyurethane foam for integrated bathroom according to claim 1, characterized in that: The catalyst is selected from at least two of DMEA, PC8, A33, PC41, and TMR2.

8. The polyurethane foam for integrated bathroom according to claim 1, characterized in that: The silicone oil is selected from at least one of AK8805, B8545 or DC193.

9. A method for preparing an integral bathroom wallboard using the polyurethane foam according to any one of claims 1 to 8, characterized in that: The steps include: (1) Component A is mixed evenly and placed in a sealed container; (2) Component B, packed in a sealed container; (3) Components A and B are mixed evenly in a high-pressure casting machine according to the mass ratio and then injected into a mold with tiles at the bottom. After the mold is closed, the components are foamed and matured to obtain an integrated bathroom wall panel.

10. The method for preparing an integrated bathroom wallboard according to claim 9, characterized in that: In the step (3), the mixing temperature of component A and component B is 15° C.-25° C., and the mixing pressure is 60 bar-120 bar.

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