Single-component polyurethane foam joint mixture and preparation method thereof

Abstract

The invention provides a single-component polyurethane foam joint mixture which comprises the following raw materials: a white material, a black material and an aerosol propellant, the white material comprises the following components in percentage by weight: 20-40% of polyether polyol, 2-10% of a disulfide bond-containing hydroxyl compound, 2-10% of other hydroxyl and amino compounds, 35-60% of chlorinated paraffin, 1.5-5% of a foam stabilizer, 0.5-2% of a catalyst, 1-5% of an anti-ultraviolet antioxidant and 3-5% of a flame retardant; the black material is isocyanate and comprises PAPI or MDI; the aerosol propellant comprises a mixture of dimethyl ether and propane and butane. The invention further provides a preparation method of the single-component polyurethane foam joint mixture. The preparation method comprises the steps of white material preparation, filling and packaging, curing and the like. The material has excellent toughness and fatigue resistance, and meets the construction requirements of multiple scenes such as severe cold areas and indoor low temperature. The flame-retardant efficiency is remarkably improved, and no negative influence is generated on the foaming ratio, bonding strength and other core properties of foam.

Description

Technical Field

[0001] This invention relates to the field of foam sealant technology, and in particular to a single-component polyurethane foam sealant and its preparation method. Background Technology

[0002] Foam sealant, typically referring to polyurethane foam sealant, mainly consists of polyurethane prepolymer, foaming agent, and catalyst. It is a product of the cross-fertilization of aerosol technology and polyurethane foam technology. It is a special polyurethane product that contains polyurethane prepolymer, foaming agent, catalyst, and other components in a pressurized aerosol can. It is suitable for sealing leaks, filling gaps, fixing and bonding, and providing thermal and sound insulation, especially for sealing leaks and waterproofing between PVC or aluminum alloy doors, windows, and walls.

[0003] The surface drying time of polyurethane foam sealant is approximately 10 minutes (at room temperature of 20℃). The full drying time varies depending on ambient temperature and humidity. Generally, it takes about 4-6 hours to fully dry in summer and 24 hours or longer in winter at around 0℃. Under normal use conditions (and with an external coating), its estimated service life is no less than ten years. The cured foam maintains good elasticity and adhesion within a temperature range of -10℃ to 80℃. The cured foam has functions such as filling, bonding, and sealing. Furthermore, flame-retardant polyurethane sealant can achieve flame-retardant ratings of B and C.

[0004] However, current polyurethane foam sealants still have some problems in use. First, the reactivity of hydroxyl groups and isocyanates decreases significantly at low temperatures, making them prone to insufficient foaming and adhesion failure when used in winter or in frigid northern regions. Second, the foam becomes more brittle after curing, making it prone to cracking after long-term use. Therefore, a better polyurethane foam sealant product is needed. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a single-component polyurethane foam sealant and its preparation method, which solves the problems of being unsuitable for low-temperature environments and prone to cracking after curing.

[0006] In a first aspect, this invention proposes a single-component polyurethane foam sealant, the raw materials of which include white component, black component, and aerosol propellant, wherein:

[0007] The white component comprises, by weight percentage: 20%-40% polyether polyol, 2%-10% disulfide-bonded hydroxyl compounds, 2%-10% other hydroxyl and amino compounds, 35%-60% chlorinated paraffin, 1.5%-5% foam stabilizer, 0.5%-2% catalyst, 1%-5% UV stabilizer and antioxidant, and 3%-5% flame retardant;

[0008] The black material is an isocyanate, including PAPI or MDI;

[0009] The aerosol propellant comprises a mixture of dimethyl ether and propane.

[0010] Preferably, the hydroxyl value of the polyether polyol is 300-500 mg KOH / g.

[0011] Preferably, the disulfide-containing hydroxyl compound includes one of dithiodiethylene glycol, 3,3'-dithiodipropanol, or dithiobis(hydroxymethyl)propane.

[0012] Preferably, the other hydroxyl and amino compounds include trimethylolpropane or diethanolamine.

[0013] Preferably, the foam stabilizer includes polyether-modified organosiloxane, polyoxyethylene-polyoxypropylene-based organosilicon copolymer, or organosilicon-polyether block copolymer.

[0014] Preferably, the catalyst comprises one of triethylenediamine, dibutyltin dilaurate, or N,N-dimethylcyclohexylamine.

[0015] Preferably, the UV-resistant antioxidant comprises a mixture of UV absorber UV-531 and antioxidant 1010 or a mixture of UV absorber UV-531 and antioxidant 168.

[0016] Preferably, the flame retardant includes one of decabromodiphenyl ether, antimony trioxide, or triphenyl phosphate.

[0018] This invention also proposes a method for preparing a one-component polyurethane foam sealant, comprising the following steps:

[0019] S1. Preparation of white material: In the order of polyether polyol, chlorinated paraffin, disulfide bond hydroxyl compound, other hydroxyl and amino compounds, foam stabilizer, catalyst, anti-ultraviolet antioxidant, and flame retardant, the raw materials are added into the reaction vessel according to the formula amount, mixed and stirred evenly to prepare white material.

[0020] S2. Filling and Packaging: On the filling production line, white material is filled into the aerosol cans using a metering pump at a filling volume of 0.4-0.5 g / mL. Then, black material is immediately filled, with the mass ratio of black material to white material controlled at 1:1.2-1:1.5. After the black material is filled, the aerosol cans are quickly sealed. Then, the aerosol propellant is filled into the cans through the filling valve at a filling pressure of 0.8-1.2 MPa, with a filling volume of 15%-20% of the can volume. Finally, the cans are capped to complete the filling process, and the aerosol cans are put into a shaking mixer for shaking until the white material, black material, and propellant in the cans are fully and evenly mixed.

[0021] S3. Maturation: The shaken and mixed product is sent to a constant temperature and humidity maturation warehouse. The maturation temperature is controlled at 20-25℃, the humidity at 35%-60%, and the maturation time is 7-10 days. After passing the inspection, it can be packaged and stored.

[0022] Preferably, in step S2, the volume ratio of dimethyl ether to propane in the aerosol propellant is 1:1 to 2:1.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. This invention introduces a disulfide-bonded hydroxyl compound into the white material raw material. The disulfide bond (-SS-) in the molecule can serve as a flexible crosslinking point embedded in the polyurethane molecular backbone. On the one hand, the flexibility of the disulfide bond can enhance the mobility of the molecular chain segments, giving the foam both excellent toughness and fatigue resistance, solving the problem of high brittleness and easy cracking after curing of traditional foam formulations. On the other hand, the disulfide bond can activate adjacent hydroxyl groups, enhancing their reactivity with isocyanates. Even at low temperatures of 5-10℃, the polymerization reaction can still proceed smoothly, overcoming the limitations of existing formulations that are prone to insufficient foaming and adhesion failure during low-temperature construction. This invention is suitable for construction needs in various scenarios such as extremely cold regions and low indoor temperatures.

[0025] 2. This invention also incorporates chlorinated paraffin, which releases HCl gas upon high-temperature combustion, diluting the concentration of combustible gases in the combustion zone and blocking oxygen contact (gas-phase flame retardancy). Combined with auxiliary flame retardants such as decabromodiphenyl ether and antimony trioxide, through synergistic effects, a dense char layer can be rapidly formed on the foam's burning surface, blocking heat transfer and material diffusion (condensed-phase flame retardancy). Compared to traditional single-flame retardant formulations, this system significantly improves flame retardant efficiency. Simultaneously, the selected flame retardants exhibit excellent compatibility with core components such as polyether polyols and isocyanates, avoiding the stratification and sedimentation phenomena common in traditional flame retardant formulations, and without negatively impacting the foam's expansion ratio, bonding strength, or other core properties. Detailed Implementation

[0026] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] Example 1:

[0028] The single-component polyurethane foam sealant in this embodiment uses the following raw materials:

[0029] White component (by weight percentage): 20% polyether polyol, 2% disulfide bond hydroxyl compound, 6% other hydroxyl and amino compounds, 55% chlorinated paraffin, 5% foam stabilizer, 2% catalyst, 5% UV stabilizer and antioxidant, 5% flame retardant;

[0030] The black material is PAP;

[0031] The aerosol propellant is a mixture of dimethyl ether and propane.

[0032] Specifically, the hydroxyl value of the polyether polyol is 300 mg KOH / g. The disulfide-bonded hydroxyl compound is diethylene glycol dithiocarbamate. Other hydroxyl and amino compounds are trimethylolpropane. The foam stabilizer is a polyether-modified organosiloxane. The catalyst is triethylenediamine. The UV absorber and antioxidant is a mixture of UV absorber UV-531 and antioxidant 1010 in equal proportions. The flame retardant is decabromodiphenyl ether.

[0033] The preparation method is as follows:

[0034] (1) Preparation of white material: In the order of polyether polyol, chlorinated paraffin, disulfide bond hydroxyl compound, other hydroxyl and amino compounds, foam stabilizer, catalyst, anti-ultraviolet antioxidant, flame retardant, the raw materials are added into the reaction vessel in sequence according to the formula amount, and mixed and stirred evenly to prepare white material;

[0035] (2) Filling and Packaging: In this embodiment, a 500mL aerosol can is used. On the filling production line, the white material is filled into the aerosol can by a metering pump at a filling amount of 0.4g / mL. Then, the black material is filled immediately. The mass ratio of black material to white material is controlled at 1:1.2. After the black material is filled, the aerosol can is quickly sealed. Then, the aerosol propellant is filled into the can through the filling valve. The volume ratio of dimethyl ether to propane in the aerosol propellant is 1:1. The filling pressure is 0.8MPa and the filling amount is 15% of the can volume. Finally, the can is capped to complete the filling. The aerosol can is then put into a shaking mixer for shaking until the white material, black material and propellant in the can are fully mixed and uniform.

[0036] (3) Curing: The product after shaking and mixing is sent to a constant temperature and humidity curing warehouse. The curing temperature is controlled at 20℃, the humidity is 40%, and the curing time is 7 days. After passing the inspection, it can be packaged and stored.

[0038] Example 2:

[0039] The single-component polyurethane foam sealant in this embodiment uses the following raw materials:

[0040] White component (by weight percentage): 21% polyether polyol, 3% disulfide-bonded hydroxyl compounds, 10% other hydroxyl and amino compounds, 60% chlorinated paraffin, 1.5% foam stabilizer, 0.5% catalyst, 1% UV stabilizer and antioxidant, and 3% flame retardant;

[0041] The black material is isocyanate, specifically PAPI or MDI;

[0042] The aerosol propellant is a mixture of dimethyl ether and propane.

[0043] Specifically, the hydroxyl value of the polyether polyol is 400 mg KOH / g. The disulfide-bonded hydroxyl compound is 3,3'-dithiodipropanol. Other hydroxyl and amino compounds are diethanolamine. The foam stabilizer is a polyoxyethylene-polyoxypropylene-based silicone copolymer. The catalyst is dibutyltin dilaurate. The UV absorber and antioxidant is a mixture of UV absorber UV-531 and antioxidant 168 in equal proportions. The flame retardant is antimony trioxide.

[0044] The preparation method is as follows:

[0045] (1) Preparation of white material: In the order of polyether polyol, chlorinated paraffin, disulfide bond hydroxyl compound, other hydroxyl and amino compounds, foam stabilizer, catalyst, anti-ultraviolet antioxidant, flame retardant, the raw materials are added into the reaction vessel in sequence according to the formula amount, and mixed and stirred evenly to prepare white material;

[0046] (2) Filling and sealing: In this embodiment, a 500mL aerosol can is used. On the filling production line, the white material is filled into the aerosol can by a metering pump at a filling amount of 0.45g / mL. Then, the black material is filled immediately. The mass ratio of black material to white material is controlled at 1:1.4. After the black material is filled, the aerosol can is quickly sealed. Then, the aerosol propellant is filled into the can through the filling valve. The volume ratio of dimethyl ether to propane and butane in the aerosol propellant is 1.5:1. The filling pressure is 1.0MPa and the filling amount is 18% of the can volume. Finally, the can is capped to complete the filling. The aerosol can is then put into a shaking mixer for shaking until the white material, black material and propellant in the can are fully mixed and uniform.

[0047] (3) Curing: The product after shaking and mixing is sent to a constant temperature and humidity curing warehouse. The curing temperature is controlled at 22℃, the humidity is 50%, and the curing time is 8 days. After passing the inspection, it can be packaged and stored.

[0049] Example 3:

[0050] The single-component polyurethane foam sealant in this embodiment uses the following raw materials:

[0051] White component (by weight percentage): 40% polyether polyol, 10% disulfide-bonded hydroxyl compounds, 2% other hydroxyl and amino compounds, 35% chlorinated paraffin, 4% foam stabilizer, 1.5% catalyst, 3.5% UV stabilizer and antioxidant, and 4% flame retardant;

[0052] The black material is isocyanate, specifically PAPI or MDI;

[0053] The aerosol propellant is a mixture of dimethyl ether and propane.

[0054] Specifically, the polyether polyol has a hydroxyl value of 500 mg KOH / g. The disulfide-containing hydroxyl compound is dithiobis(hydroxymethyl)propane. Other hydroxyl and amino compounds are trimethylolpropane. The foam stabilizer is an organosilicon polyether block copolymer. The catalyst is N,N-dimethylcyclohexylamine. The UV absorber and antioxidant is a mixture of UV absorber UV-531 and antioxidant 1010 in equal proportions. The flame retardant is triphenyl phosphate.

[0055] The preparation method is as follows:

[0056] (1) Preparation of white material: In the order of polyether polyol, chlorinated paraffin, disulfide bond hydroxyl compound, other hydroxyl and amino compounds, foam stabilizer, catalyst, anti-ultraviolet antioxidant, flame retardant, the raw materials are added into the reaction vessel in sequence according to the formula amount, and mixed and stirred evenly to prepare white material;

[0057] (2) Filling and sealing: In this embodiment, a 500mL aerosol can is used. On the filling production line, the white material is filled into the aerosol can by a metering pump at a filling amount of 0.5g / mL. Then, the black material is filled immediately. The mass ratio of black material to white material is controlled at 1:1.5. After the black material is filled, the aerosol can is quickly sealed. Then, the aerosol propellant is filled into the can through the filling valve. The volume ratio of dimethyl ether to propane and butane in the aerosol propellant is 2:1. The filling pressure is 1.2MPa and the filling amount is 20% of the can volume. Finally, the can is capped to complete the filling. The aerosol can is then put into a shaking mixer for shaking until the white material, black material and propellant in the can are fully mixed and uniform.

[0058] (3) Curing: The product after shaking and mixing is sent to a constant temperature and humidity curing warehouse. The curing temperature is controlled at 25℃, the humidity is 60%, and the curing time is 10 days. After passing the inspection, it can be packaged and stored.

[0060] Comparative example:

[0061] The polyurethane black and white industrial foaming agent was purchased from Langfang Lechuang Insulation Materials Co., Ltd.

[0063] The parameters of the products prepared in Comparative Examples 1-3 were compared with those of the comparative examples, and the results are shown in Table 1:

[0064]

[0065] Table 1

[0066] As can be seen from Table 1, the product of the present invention outperforms the prior art in terms of low-temperature performance, toughness, fracture resistance, and flame retardancy. This fully demonstrates the technical advantages of the embodiments of the present invention.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A one-component polyurethane foam sealant, characterized in that, The raw materials include white material, black material, and aerosol propellant, among which: The white component comprises, by weight percentage: 20%-40% polyether polyol, 2%-10% disulfide-bonded hydroxyl compounds, 2%-10% other hydroxyl and amino compounds, 35%-60% chlorinated paraffin, 1.5%-5% foam stabilizer, 0.5%-2% catalyst, 1%-5% UV stabilizer and antioxidant, and 3%-5% flame retardant; The black material is an isocyanate, including PAPI or MDI; The aerosol propellant comprises a mixture of dimethyl ether and propane.

2. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The hydroxyl value of the polyether polyol is 300-500 mg KOH / g.

3. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The disulfide-containing hydroxyl compound includes one of dithiodiethylene glycol, 3,3'-dithiodipropanol, or dithiobis(hydroxymethyl)propane.

4. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The other hydroxyl and amino compounds include trimethylolpropane or diethanolamine.

5. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The foaming agent includes polyether-modified organosiloxane, polyoxyethylene-polyoxypropylene-based organosilicon copolymer, or organosilicon-polyether block copolymer.

6. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The catalyst includes one of triethylenediamine, dibutyltin dilaurate, or N,N-dimethylcyclohexylamine.

7. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The UV-resistant antioxidant includes a mixture of UV absorber UV-531 and antioxidant 1010 or a mixture of UV absorber UV-531 and antioxidant 168.

8. The single-component polyurethane foam sealant as described in claim 1, characterized in that: The flame retardant includes one of decabromodiphenyl ether, antimony trioxide, or triphenyl phosphate.

9. A method for preparing the single-component polyurethane foam sealant as described in claim 1, characterized in that, Includes the following steps: S1. Preparation of white material: In the order of polyether polyol, chlorinated paraffin, disulfide bond hydroxyl compound, other hydroxyl and amino compounds, foam stabilizer, catalyst, anti-ultraviolet antioxidant, and flame retardant, the raw materials are added into the reaction vessel according to the formula amount, mixed and stirred evenly to prepare white material. S2. Filling and Packaging: On the filling production line, white material is filled into the aerosol cans using a metering pump at a filling volume of 0.4-0.5 g / mL. Then, black material is immediately filled, with the mass ratio of black material to white material controlled at 1:1.2-1:1.

5. After the black material is filled, the aerosol cans are quickly sealed. Then, the aerosol propellant is filled into the cans through the filling valve at a filling pressure of 0.8-1.2 MPa, with a filling volume of 15%-20% of the can volume. Finally, the cans are capped to complete the filling process, and the aerosol cans are put into a shaking mixer for shaking until the white material, black material, and propellant in the cans are fully and evenly mixed. S3. Curing: The shaken and mixed product is sent to a constant temperature and humidity curing warehouse. The curing temperature is controlled at 20-25℃, the humidity at 35%-60%, and the curing time is 7-10 days. After passing the inspection, it can be packaged and stored.

10. The method for preparing a single-component polyurethane foam sealant as described in claim 9, characterized in that: In step S2, the volume ratio of dimethyl ether to propane in the aerosol propellant is 1:1 to 2:1.

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