Highly flame-retardant and cold-insulating polyurethane foam and preparation method thereof

Abstract

The present invention relates to the field of material synthesis technology, and more specifically to a highly flame-retardant, cold-insulating polyurethane foam and a preparation method thereof. The present invention provides a highly flame-retardant, cold-insulating polyurethane foam comprising a first component and a second component. The first component comprises, by weight, 100 parts of a polyester polyol; 1 to 5 parts of an organosilicon surfactant; 0.5 to 5.0 parts of a catalyst; 0.2 to 1.0 parts of water; and 20 to 30 parts of a flame retardant. The second component is polyphenyl polymethylene polyisocyanate. The highly flame-retardant, cold-insulating polyurethane foam provided by the present invention has high flame retardancy, excellent stability, and mechanical properties.

Description

Technical Field

[0001] The invention relates to the technical field of material synthesis, and in particular to a highly flame-retardant and cold-insulating polyurethane foam and a preparation method thereof. Background Art

[0002] An LNG base station is a site for receiving, storing, and then exporting LNG to customers. It mainly includes an unloading terminal, LNG storage tanks, BOG area, recondensation area, gasification area, etc. Each area is connected by large and small pipelines. Pipe supports are an important part of the pipeline system, serving the purpose of supporting and fixing the pipeline. Pipe supports not only need to fix the pipeline, but also have good cold-insulation properties to reduce heat transfer, ensure pipeline safety, and reduce energy consumption.

[0003] Currently, high-density polyurethane foam is the primary choice for cold-insulation pipe supports in the LNG industry. Polyurethane foam offers advantages such as chemical stability, acid and alkali resistance, low water absorption, high specific strength, and low thermal conductivity. However, most commercially available polyurethane pipe supports are non-flame-retardant or have poor flame retardancy, posing safety risks during LNG pipeline construction and subsequent use and maintenance. With the rapid development of LNG receiving terminals, demand for cold-insulation pipe supports is enormous. Therefore, there is an urgent need to develop an environmentally friendly, highly flame-retardant polyurethane foam for LNG pipe supports. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention proposes a highly flame-retardant and cold-insulating polyurethane foam and a preparation method thereof. The highly flame-retardant and cold-insulating polyurethane foam provided by the present invention has high flame retardancy, excellent stability and mechanical properties (including compressive strength, tensile strength, shear strength, etc.).

[0005] In order to achieve the above objectives, the present invention provides the following technical solutions.

[0006] The present invention provides a highly flame-retardant and cold-insulating polyurethane foam, comprising a first component and a second component;

[0007] The first component, calculated by mass, includes the following components:

[0008] 100 parts of polyester polyol;

[0009] 1-5 parts of organosilicon surfactant;

[0010] 0.5-5.0 parts of catalyst;

[0011] 0.2-1.0 parts of water;

[0012] 20-30 parts of flame retardant;

[0013] The second component is polyphenyl polymethylene polyisocyanate; the mass ratio of the first component to the second component is 100:140-200.

[0014] Preferably, the viscosity of the polyester polyol at 25° C. is 3000 to 20000 mPa.s, and the hydroxyl value of the polyester polyol is 150 to 350 mgKOH / g.

[0015] Preferably, the polyester polyol is obtained by condensing raw material A and raw material B;

[0016] The raw material A includes one or more of phthalic anhydride, isophthalic acid and terephthalic acid;

[0017] The raw material B includes one or more of ethylene glycol, propylene glycol, butanediol and bisphenol A.

[0018] Preferably, the catalyst includes one or more of a foaming catalyst, a gel catalyst and a trimerization catalyst.

[0019] Preferably, the flame retardant is one or more of tris(2-chloropropyl)phosphate, tris(2-chloroethyl)phosphate, triethyl phosphate, dimethyl methylphosphonate, and diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate.

[0020] Preferably, the polyphenylpolymethylene polyisocyanate has a viscosity of 150 to 700 mPa.s at 25° C., an NCO mass content of 30 to 32%, and a functionality of 2.6 to 3.0.

[0021] Preferably, the preparation of the first component comprises the following steps:

[0022] The polyester polyol, the organosilicon surfactant, the catalyst, water and the flame retardant are mixed and then defoamed to obtain a first component.

[0023] The present invention also provides a method for preparing the highly flame-retardant and cold-insulating polyurethane foam described in the above technical solution, comprising the following steps:

[0024] After the first component and the second component are mixed, the resulting mixture is subjected to foaming molding and aging in sequence to obtain the highly flame-retardant and cold-insulating polyurethane foam.

[0025] Preferably, the mold temperature used in the foaming molding is controlled at 60-80°C.

[0026] Preferably, the aging temperature is room temperature and the aging time is 48 hours.

[0027] The present invention provides a highly flame-retardant, cold-insulating polyurethane foam, comprising a first component and a second component. The first component comprises, by weight, the following components: 100 parts of a polyester polyol; 1-5 parts of an organosilicon surfactant; 0.5-5.0 parts of a catalyst; 0.2-1.0 parts of water; and 20-30 parts of a flame retardant. The second component is polyphenylpolymethylene polyisocyanate. In the present invention, the polymer chain formed by polymerization of the polyester polyol and the polyphenylpolymethylene polyisocyanate contains a higher content of benzene groups. The six-membered benzene ring structure imparts superior stability and mechanical properties to the polyurethane foam. Furthermore, the polyphenylpolymethylene polyisocyanate in the highly flame-retardant, cold-insulating polyurethane foam after polymerization has a relatively high quality, with an NCO index greater than 200. The excess NCO groups, under the action of the catalyst, form a six-membered polyisocyanurate ring structure, enhancing the flame retardancy and thermal stability of the polyurethane foam. The benzene rings and hexacyclic polyisocyanurate rings in the polyurethane foam polymer chain have a higher decomposition temperature, easily forming a carbonized layer during combustion. This carbonized layer acts as a heat and air barrier, providing enhanced fire resistance and reducing heat release. Using water as the blowing agent, it is environmentally friendly, with zero ozone depletion and low greenhouse gas emissions. DETAILED DESCRIPTION

[0028] The present invention provides a highly flame-retardant and cold-insulating polyurethane foam, comprising a first component and a second component;

[0029] The first component, calculated by mass, includes the following components:

[0030] 100 parts of polyester polyol;

[0031] 1-5 parts of organosilicon surfactant;

[0032] 0.5-5.0 parts of catalyst;

[0033] 0.2-1.0 parts of water;

[0034] 20-30 parts of flame retardant;

[0035] The second component is polyphenylpolymethylene polyisocyanate.

[0036] In the present invention, the mass ratio of the first component to the second component is preferably 100:140-200, more preferably 100:160-180.

[0037] In the present invention, the first component comprises 100 parts by mass of a polyester polyol. In the present invention, the viscosity of the polyester polyol at 25° C. is preferably 3,000 to 20,000 mPa.s, more preferably 5,000 to 15,000 mPa.s; and the hydroxyl value of the polyester polyol is preferably 150 to 350 mgKOH / g, more preferably 200 to 300 mgKOH / g.

[0038] In the present invention, the first component comprises 1 to 5 parts by mass of an organosilicon surfactant, preferably 2 to 4 parts; the organosilicon surfactant is preferably the S series products of Shanghai Maihao Chemical Technology Co., Ltd., the B series products of Evonik Group, the L series products of Maitu High-tech Materials or the AK series products of Jiangsu Meside Chemical Co., Ltd., and is further preferably S-70 of Shanghai Maihao Chemical Technology Co., Ltd.

[0039] In the present invention, the first component comprises 0.5 to 5.0 parts by mass of a catalyst, preferably 1 to 4 parts; in the present invention, the catalyst preferably comprises one or more of a foaming catalyst, a gel-type catalyst and a trimerization catalyst. In the present invention, the foaming catalyst preferably comprises one or more of pentamethyldiethylenetriamine, dimorpholine diethyl ether and bis(dimethylaminoethyl) ether; the gel-type catalyst preferably comprises N,N-dimethylcyclohexylamine and / or triethylenediamine; the trimerization catalyst preferably comprises one or more of N,N'N"-tris(dimethylaminopropyl)-hexahydrotriazine, 2,4,6-tris(dimethylaminomethyl)phenol, a quaternary ammonium salt, a soluble potassium salt and a soluble sodium salt; the soluble potassium salt is preferably potassium isooctanoate.

[0040] In the present invention, the first component comprises 0.2 to 1.0 parts of water, preferably 0.5 to 0.8 parts by mass.

[0041] In the present invention, the first component comprises 20 to 30 parts by mass of a flame retardant, preferably 25 parts. In the present invention, the flame retardant is preferably one or more of tris(2-chloropropyl)phosphate, tris(2-chloroethyl)phosphate, triethyl phosphate, dimethyl methylphosphonate, and diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate, more preferably a mixture of tris(2-chloropropyl)phosphate and diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate, and the mass ratio of tris(2-chloropropyl)phosphate to diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate in the mixture is preferably 1:1.

[0042] In the present invention, the preparation of the first component preferably includes the following steps:

[0043] The polyester polyol, the organosilicon surfactant, the catalyst, water and the flame retardant are mixed and then defoamed to obtain a first component.

[0044] In the present invention, the mixing method is preferably stirring; the stirring speed is preferably 500 rpm; the mixing is preferably carried out in a stainless steel mixing kettle; and the defoaming method is preferably standing for 1 hour.

[0045] In the present invention, the second component is polyphenyl polymethylene polyisocyanate; the viscosity of the polyphenyl polymethylene polyisocyanate at 25° C. is preferably 150 to 700 mPa.s, the mass content of NCO is preferably 30 to 32%, and the functionality is preferably 2.6 to 3.0.

[0046] The present invention also provides a method for preparing the highly flame-retardant and cold-insulating polyurethane foam described in the above technical solution, comprising the following steps:

[0047] After the first component and the second component are mixed, the resulting mixture is subjected to foaming molding and aging in sequence to obtain the highly flame-retardant and cold-insulating polyurethane foam.

[0048] In the present invention, the mold temperature used in the foaming molding is controlled at 60-80° C., more preferably 65-75° C. In the present invention, the aging temperature is preferably room temperature; and the aging time is preferably 48 hours.

[0049] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0050] The sources of raw materials used in the embodiments and comparative examples are as follows:

[0051] Polyester polyol AK-POL-4008, hydroxyl value 250 mgKOH / g, viscosity 12000 mPa·s, purchased from Aekyung (Ningbo) Chemical Co., Ltd.

[0052] Silicone surfactant S-70 was purchased from Shanghai Maihao Chemical Technology Co., Ltd.

[0053] Polyurethane composite catalyst: bis(dimethylaminoethyl) ether (A-1), N,N-dimethylcyclohexylamine (PC8), and potassium isooctanoate (K-15); purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd.

[0054] The flame retardant tris(2-chloropropyl) phosphate (TCPP) was purchased from Zhejiang Wansheng Co., Ltd.

[0055] Flame retardant diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate (WSFR-6) was purchased from Zhejiang Wansheng Co., Ltd.

[0056] Polyphenylpolymethylene polyisocyanate: PM 200, NCO content 31.5%, viscosity 200-250 mPa.s, purchased from Wanhua Chemical.

[0057] Example 1

[0058] According to the weight parts of each component in Table 1, the first component of Examples 1 to 6 (denoted as S1 to S6) was prepared.

[0059] Table 1: Formula of Component A in Examples 1 to 6

[0060] Components S1 S2 S3 S4 S5 S6 AK-POL-4008 100 100 100 100 100 100 S-70 3 3 3 3 3 3 A-1 0.2 0.2 0.2 0.2 0.2 0.2 PC8 0.5 0.5 0.5 0.5 0.5 0.5 K-15 1.0 1.0 1.0 1.0 1.0 1.0 TCPP 10 15 10 20 15 15 WSFR-6 10 15 20 10 15 15 water 0.8 1.0 1.0 1.0 0.5 0.2

[0061] According to the mixing ratio of the first component and the second component in Table 2, polyurethane foam S1-6 was prepared;

[0062] Table 2S1-6 Mass ratio of the first component to the second component

[0063] S1 S2 S3 S4 S5 S6 First component: Second component 1 / 1.8 1 / 1.8 1 / 1.8 1 / 1.8 1 / 1.7 1 / 1.6

[0064] Preparation method:

[0065] The first component of each embodiment was uniformly mixed according to the mass fractions in Table 1 in a stainless steel mixing kettle with a safety device and a stirring speed of 500 rpm for 0.5 hours, and allowed to stand for 1 hour to defoam, to obtain the first component;

[0066] The first component and the second component were mixed according to the mass ratio in Table 2, poured and mixed by a high-pressure machine for foaming and aging at room temperature. The temperature of the foaming mold was 70° C. and the aging time at room temperature was 48 h.

[0067] The properties of the foams of Examples 1 to 6 were tested. The performance tests were conducted using the following standards: apparent density according to GB / T 6343-2009, closed porosity according to GB / T 10799-2008, compressive strength according to GB / T 8813-2020, thermal conductivity according to GB / T 10294-2008, soluble chloride ion content according to JC / T 618-2005, oxygen index according to GB / T 2406.2-2009, and flammability grade according to GB 8624. The test results are shown in Table 3.

[0068] Table 3 Properties of rigid polyurethane foams prepared from S1-6

[0069]

[0070]

[0071] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A highly flame-retardant and cold-insulating polyurethane foam, characterized in that: It consists of a first component and a second component; The first component, calculated by mass, comprises: 100 parts of polyester polyol; 1-5 parts of organosilicon surfactant; 0.5-5.0 parts of catalyst; 0.2-1.0 parts of water; 20-30 parts of flame retardant; The second component is polyphenyl polymethylene polyisocyanate; the mass ratio of the first component to the second component is 100:140-200; The flame retardants are tris(2-chloropropyl)phosphate and diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate; The catalyst comprises bis(dimethylaminoethyl) ether, N,N-dimethylcyclohexylamine and potassium isooctanoate; the mass proportions of the bis(dimethylaminoethyl) ether, N,N-dimethylcyclohexylamine and potassium isooctanoate are 0.2 parts, 0.5 parts and 1 part respectively.

2. The highly flame-retardant and cold-insulating polyurethane foam according to claim 1, wherein: The viscosity of the polyester polyol at 25° C. is 3,000 to 20,000 mPa·s, and the hydroxyl value of the polyester polyol is 150 to 350 mgKOH / g.

3. The highly flame-retardant and cold-insulating polyurethane foam according to claim 1, wherein: The polyphenyl polymethylene polyisocyanate has a viscosity of 150 to 700 mPa·s at 25° C., an NCO mass content of 30 to 32%, and a functionality of 2.6 to 3.

0.

4. The highly flame-retardant and cold-insulating polyurethane foam according to claim 1, wherein: The preparation of the first component comprises the following steps: The polyester polyol, the organosilicon surfactant, the catalyst, water and the flame retardant are mixed and then defoamed to obtain a first component.

5. The method for preparing the highly flame-retardant and cold-insulating polyurethane foam according to any one of claims 1 to 4, characterized in that: The following steps are involved: After the first component and the second component are mixed, the resulting mixture is subjected to foaming molding and aging in sequence to obtain the highly flame-retardant and cold-insulating polyurethane foam.

6. The preparation method according to claim 5, characterized in that The temperature of the mold used in the foaming molding is controlled at 60-80°C.

7. The preparation method according to claim 5, characterized in that The aging temperature is room temperature and the aging time is 48 hours.

Images