Polymer polyol as well as preparation method and application thereof

Abstract

The invention provides polymer polyol and a preparation method and application thereof, and the preparation method comprises the following steps: step 1, carrying out a first polymerization reaction in a first reaction system containing a first ethylenically unsaturated monomer and a first modified monomer to form a prepolymer; and 2, carrying out a second polymerization reaction in a second reaction system containing the prepolymer, a second ethylenically unsaturated monomer, a second modified monomer and polyether polyol to prepare the polymer polyol. The polymer polyol prepared by the method provided by the invention has excellent viscosity characteristic, and the method also improves the conversion rate of olefin monomer raw materials, improves the particle size distribution of the polymer polyol, and reduces the removal difficulty of volatile components in the product.

Description

Technical Field

[0001] The present application relates to the field of polymers, and more specifically to a polymer polyol and a preparation method thereof, and the present application relates to the use of the polymer polyol as a raw material in polyurethane synthesis. Background Art

[0002] Polymer polyols (POPs) are an important class of chemical raw materials and one of the important raw materials for polyurethane products. Polymer polyols are usually a modified polyether formed by graft copolymerization of polyether polyols and ethylenically unsaturated compounds. Polyurethane foams made from such polymer polyols have both the toughness of the polyether matrix and the rigidity of the vinyl side chains. These properties can significantly improve the modulus, tensile strength, tear strength, hardness and flame retardancy of polyurethane foams and elastomers, and can effectively reduce the density of the material. Therefore, there is a very high demand for high-performance POPs in the field of polyurethane manufacturing.

[0003] However, the existing polymer polyol synthesis process is not satisfactory, and the performance of the existing polymer polyol often needs to be improved. For example, people are very much in need of the raw material POP for preparing polyurethane to have low viscosity at high solid content, but the POP prepared by the prior art cannot show the required low viscosity at high solid content, or can only synthesize POP with the required high solid content and low viscosity performance through extremely complex process steps or process improvements, and the complex process will significantly increase the synthesis cost to a level that is not suitable for industrialization. These POP synthesis processes in the prior art also have other problems, such as low conversion rate of ethylenically unsaturated monomers, great difficulty in separating volatile components in the product, high process energy consumption, difficult process control, etc. It has never been realized in the prior art that the particle size control of the intermediate product and the final product in the process of synthesizing POP can affect the viscosity performance of the synthesized POP.

[0004] Therefore, people are very much looking forward to developing a new method to synthesize POP at low cost with simple steps, which can simply and effectively control the particle size and viscosity properties of the POP product, and can effectively solve the problems existing in the prior art, such as low conversion rate of ethylenically unsaturated monomers, difficulty in separating volatile components in the product, high process energy consumption, and difficulty in process control.

[0005] In order to solve the above problems, the applicant has invested a lot of energy in conducting in-depth and extensive research, and unexpectedly developed the method of the present application, which effectively solves the above problems existing in the prior art. Summary of the invention

[0006] The first aspect of the present application provides a step-by-step polymerization method for preparing a polymer polyol, the method comprising:

[0007] Step 1: a first polymerization reaction occurs in a first reaction system comprising a first ethylenically unsaturated monomer and a first modifying monomer to form a prepolymer, wherein the first reaction system further comprises a first chain transfer agent and a first initiator;

[0008] Step 2: a second polymerization reaction occurs in a second reaction system comprising the prepolymer, a second ethylenically unsaturated monomer, a second modified monomer, and a polyether polyol to obtain the polymer polyol, wherein the second reaction system further comprises a second chain transfer agent and a second initiator;

[0009] The first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, halogenated C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, C6-C22 aromatic olefins containing at least one carbon-carbon double bond, halogenated C6-C22 aromatic olefins containing at least one carbon-carbon double bond, C2-C12 nitrile containing at least one carbon-carbon double bond, C2-C12 carboxylic acid containing at least one carbon-carbon double bond, C2-C12 carboxylic acid (C1-C12) alkyl ester containing at least one carbon-carbon double bond;

[0010] The second reaction system comprises a polyether polyol having a number average molecular weight of 400-9000;

[0011] The first modified monomer and the second modified monomer are the same as or different from each other, and are independently a polyether polyol connected with a modified group, and have a number average molecular weight of 2000-20000. The modified group is selected from one or more of the following: a carbon-carbon double bond, a carbon-carbon triple bond.

[0012] According to one embodiment of the first aspect of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: styrene, methyl styrene, chlorostyrene, (meth)acrylonitrile, (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate and butyl (meth)acrylate.

[0013] According to another embodiment of the first aspect of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are both a mixture of styrene and acrylonitrile, and the mass ratio of styrene to acrylonitrile is 80:20 to 20:80.

[0014] According to another embodiment of the first aspect of the present application, the first modifying monomer and the second modifying monomer are the same as or different from each other, and are independently selected from: polyether polyols modified with m-phenylenedimethyl isocyanate, polyether polyols modified with 3-isopropyl-dimethylbenzyl isocyanate (TMI), polyether polyols modified with (meth)acrylate (C1-C6) hydroxyalkyl ester, and polyether polyols modified with glycidyl methacrylate.

[0015] According to another embodiment of the first aspect of the present application, the first chain transfer agent and the second chain transfer agent are the same as or different from each other, and are independently selected from one or more of the following: isopropanol, n-butanol, tert-butanol, toluene, ethylbenzene, xylene, hexane, ethyl acetate, butyl acetate, mercaptan or dimethylformamide. According to another embodiment of the first aspect of the present application, the first initiator and the second initiator are the same as or different from each other, and are independently selected from one or more of the following: azobisbutyronitrile (AIBN), dimethyl azobisisobutyrate, benzoyl peroxide, tert-butyl peroxide (2-ethylhexanoate), diethyl peroxide tert-butyl acetate, tert-amyl peroxide (2-ethylhexanoate) and 1,1-di(tert-amylperoxy)cyclohexane.

[0016] According to another embodiment of the first aspect of the present application, based on the total weight of the first reaction system, the first reaction system comprises 10-40 weight % of a first ethylenically unsaturated monomer, 15-40 weight % of a first modifying monomer, 50-75 weight % of a first chain transfer agent and 0.01-0.5 weight % of a first initiator.

[0017] According to another embodiment of the first aspect of the present application, based on the total weight of the second reaction system, the second reaction system comprises 3-20 weight % of a prepolymer, 10-50 weight % of a second ethylenically unsaturated monomer, 1-10 weight % of a second modifying monomer, 3-15 weight % of a second chain transfer agent, 0.01-5 weight % of a second initiator, and 20-60 weight % of a polyether polyol.

[0018] According to another embodiment of the first aspect of the present application, the volume particle size distribution D[4,3] of the prepolymer is 0.2-0.85 microns, and the volume particle size distribution D[4,3] of the polymer polyol is 1-5.5 microns.

[0019] The second aspect of the present application provides a polymer polyol, which is prepared by the above method of the present application.

[0020] The third aspect of the present application provides a polyurethane material, which is prepared by reacting an isocyanate raw material with an isocyanate-reactive compound, wherein the isocyanate-reactive compound includes the polymer polyol of the present invention; the isocyanate raw material contains two or more isocyanate groups, or modified groups thereof.

[0021] In the following specific implementation section, the method and POP of the present application are further introduced in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 shows the particle size distribution of the prepolymer prepared using Example 1 of the present application;

[0023] Figure 2 shows the particle size distribution of the prepolymer prepared using Example 2 of the present application;

[0024] Figure 3 The particle size distribution diagram of the prepolymer prepared using Example 3 of the present application is shown. DETAILED DESCRIPTION

[0025] "Range" disclosed herein is in the form of lower limit and upper limit. It can be one or more lower limits, and one or more upper limits respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower limit and upper limit define the boundaries of a particular range. All ranges that can be defined in this way are inclusive and combinable, i.e. any lower limit can be combined with any upper limit to form a range. For example, a range of 60-120 and 80-110 is listed for a particular parameter, and it is understood that a range of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following ranges can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5.

[0026] In this application, unless otherwise specified, the numerical range "ab" represents an abbreviation of any real number combination between a and b, where a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations.

[0027] In this application, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form a new technical solution.

[0028] In this application, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0029] In this application, unless otherwise specified, the term "comprising" as used herein may be open-ended or closed-ended. For example, the term "comprising" may mean that other components not listed may also be included, or may only include the listed components.

[0030] According to one embodiment of the present application, a step-by-step polymerization method for preparing a polymer polyol (POP) is provided, the method comprising: step one: a first polymerization reaction occurs in a first reaction system comprising a first ethylenically unsaturated monomer and a first modifying monomer to form a prepolymer, the first reaction system also containing a first chain transfer agent and a first initiator; and step two: a second polymerization reaction occurs in a second reaction system comprising the prepolymer, a second ethylenically unsaturated monomer, a second modifying monomer, and a polyether polyol to obtain the polymer polyol, the second reaction system also containing a second chain transfer agent and a second initiator.

[0031] It can be seen that the method of the present application includes two polymerization (copolymerization) steps, which can be carried out in the same reactor or in different reactors. Preferably, both step one and step two are carried out using a double-kettle continuous polymerization process.

[0032] According to a specific embodiment of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, halogenated C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, C6-C22 aromatic olefins containing at least one carbon-carbon double bond, halogenated C6-C22 aromatic olefins containing at least one carbon-carbon double bond, C2-C12 nitrile containing at least one carbon-carbon double bond, C2-C12 carboxylic acid containing at least one carbon-carbon double bond, C2-C12 carboxylic acid (C1-C12) alkyl ester containing at least one carbon-carbon double bond. According to another specific embodiment of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: C4-C16 aliphatic olefins containing at least one carbon-carbon double bond, halogenated C4-C16 aliphatic olefins containing at least one carbon-carbon double bond, C6-C16 aromatic olefins containing at least one carbon-carbon double bond, halogenated C6-C16 aromatic olefins containing at least one carbon-carbon double bond, C2-C8 nitrile containing at least one carbon-carbon double bond, C2-C8 carboxylic acid containing at least one carbon-carbon double bond, C2-C8 carboxylic acid (C1-C8) alkyl ester containing at least one carbon-carbon double bond. According to another specific embodiment of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: C4-C12 aliphatic olefins containing at least one carbon-carbon double bond, halogenated C4-C12 aliphatic olefins containing at least one carbon-carbon double bond, C6-C12 aromatic olefins containing at least one carbon-carbon double bond, halogenated C6-C12 aromatic olefins containing at least one carbon-carbon double bond, C2-C6 nitrile containing at least one carbon-carbon double bond, C3-C6 carboxylic acid containing at least one carbon-carbon double bond, C3-C6 carboxylic acid (C1-C6) alkyl ester containing at least one carbon-carbon double bond. The above-mentioned "halogenated" means that the hydrogen atom directly connected to the carbon atom of the corresponding compound is replaced by one or more, such as 1-6, more specifically one, two, three or four halogen atoms. The halogen atom includes fluorine, chlorine, bromine or iodine, preferably chlorine.

[0033] According to a specific embodiment of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: styrene, methyl styrene, chlorostyrene, (meth)acrylonitrile, (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate and butyl (meth)acrylate.

[0034] According to a specific embodiment of the present application, the first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are each independently a mixture of styrene and (meth)acrylonitrile, for example, the weight ratio of styrene to (meth)acrylonitrile can be 80:20 to 20:80, for example, 70:30 to 30:70, or 60:40 to 40:60, preferably 70:30 to 40:60.

[0035] According to a specific embodiment of the present application, based on the total weight of the first reaction system, that is, based on the total weight of all raw materials used in the first reaction system, the first reaction system contains 10-40 weight% of the first ethylenically unsaturated monomer, for example, 15-30 weight%, for example, within the range of values ​​obtained by combining any two of the following values: 10 weight%, 12 weight%, 15 weight%, 18 weight%, 20 weight%, 22 weight%, 25 weight%, 28 weight%, 30 weight%, 32 weight%, 35 weight%, 38 weight%, 40 weight%.

[0036] According to another specific embodiment of the present application, based on the total weight of the second reaction system, that is, based on the total weight of all raw materials used in the second reaction system, the second reaction system contains 10-50 weight% of the second ethylenically unsaturated monomer, for example, 30-45 weight%, for example, within the numerical range obtained by combining any two of the following numerical values: 10 weight%, 12 weight%, 15 weight%, 18 weight%, 20 weight%, 22 weight%, 25 weight%, 28 weight%, 30 weight%, 32 weight%, 35 weight%, 38 weight%, 40 weight%, 42 weight%, 45 weight%, 48 weight%, 50 weight%.

[0037] In the present invention, the first modified monomer and the second modified monomer are modified polyether polyols, so although they are called "monomers", they contain a polymer main chain and are used as dispersants in the method of the present invention. They are called "modified monomers" in the present invention.

[0038] According to one embodiment of the present invention, the first modified monomer and the second modified monomer are the same or different from each other, and are independently connected to a polyether polyol with a modified group, such as a modified group that may contain one or more carbon-carbon double bonds and / or one or more carbon-carbon triple bonds. For example, the first modified monomer or the second modified monomer may be a polymer formed by reacting a C6-C16 aromatic polyisocyanate (containing two or more isocyanate groups), a C3-C12 carboxylic acid hydroxy C1-C6 alkyl ester containing one or more carbon-carbon unsaturated bonds with a polyether polyol, and grafting and modifying the polyether backbone of the polyether polyol. According to a specific embodiment, the monomer used to graft and modify the polyether polyol is selected from one or more of the following: m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI), (meth) acrylic acid (C1-C6) hydroxyalkyl ester, methacrylate glycidyl ester. According to one embodiment of the present application, each of the first modified monomers contains 1-10 of the above-mentioned monomers for graft modification, for example, 1-5, or 1-2.

[0039] According to one embodiment of the present application, the number average molecular weight of each of the first modifying monomer and the second modifying monomer is 2000-20000, for example, 4000-8000, or 8000-10000, or 10000-15000, or 12000-16000, or 16000-20000.

[0040] According to one embodiment of the present application, based on the total weight of the first reaction system, the first reaction system contains 15-40 weight % of the first modified monomer, for example, 20-30 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 15 weight %, 18 weight %, 20 weight %, 22 weight %, 25 weight %, 28 weight %, 30 weight %, 32 weight %, 35 weight %, 38 weight %, 40 weight %.

[0041] According to one embodiment of the present application, based on the total weight of the second reaction system, the second reaction system contains 1-10 weight % of the second modified monomer, for example, 2-5 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 1 weight %, 2 weight %, 3 weight %, 4 weight %, 5 weight %, 6 weight %, 7 weight %, 8 weight %, 9 weight %, 10 weight %.

[0042] The polyether polyol used in step 2 is different from the first modified monomer and the second modified monomer, and does not contain a modified group connected to the polyether main chain. According to one embodiment of the present application, the number average molecular weight of the polyether polyol is 400-9000, such as 600-8000, or 800-6000, or 1000-5000, or 2000-4000, or 2500-3000. According to a specific embodiment, the number average molecular weight of the polyether polyol used in step 2 is about 1000-4000, such as 2000-3000, and the hydroxyl value is 244458.

[0043] The kinetic energy is 50-60, such as 54.5-57.5, the functionality is 1-6, such as 2-3, and the viscosity at 25°C is 100-800 Pa·s, such as 400-700 Pa·s.

[0044] According to one embodiment of the present application, based on the total weight of the second reaction system, the second reaction system contains 20-60 weight % of polyether polyol, for example, 30-50 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 20 weight %, 25 weight %, 30 weight %, 35 weight %, 40 weight %, 45 weight %, 50 weight %, 55 weight %, 60 weight %.

[0045] According to one embodiment of the present application, the first chain transfer agent and the second chain transfer agent are the same as or different from each other, and are independently selected from one or more of the following: isopropanol, n-butanol, tert-butanol, toluene, ethylbenzene, xylene, hexane, ethyl acetate, butyl acetate, mercaptan or dimethylformamide.

[0046] According to one embodiment of the present application, although the first and second chain transfer agents are called "chain transfer agents", they can also be used as solvents and diluents in step one and step two, respectively, and will not be completely consumed during the polymerization reaction.

[0047] According to one embodiment of the present application, based on the total weight of the first reaction system, the first reaction system contains 50-70 weight % of the first chain transfer agent, for example, 55-65 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 50 weight %, 52 weight %, 55 weight %, 58 weight %, 60 weight %, 62 weight %, 65 weight %, 68 weight %, 70 weight %.

[0048] According to one embodiment of the present application, based on the total weight of the second reaction system, the second reaction system contains 3-15 wt % of the second chain transfer agent, for example, 5-10 wt %, for example, within the numerical range obtained by combining any two of the following numerical values: 3 wt %, 4 wt %, 5 wt %, 6 wt %, 7 wt %, 8 wt %, 9 wt %, 10 wt %, 11 wt %, 12 wt %, 13 wt %, 14 wt %, 15 wt %.

[0049] According to one embodiment of the present application, the first initiator and the second initiator are the same as or different from each other, and are each independently an azo initiator and / or a peroxide initiator. For example, the first initiator and the second initiator are each independently selected from one or more of the following: azobisbutyronitrile (AIBN), dimethyl azobisisobutyrate, benzoyl peroxide, tert-butyl peroxide (2-ethylhexanoate), tert-butyl peroxide diethylacetate, tert-amyl peroxide (2-ethylhexanoate) and 1,1-di(tert-amylperoxy)cyclohexane.

[0050] According to one embodiment of the present application, based on the total weight of the first reaction system, the first reaction system contains 0.01-0.5 weight % of the first initiator, for example, 0.05-0.1 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 0.01 weight %, 0.02 weight %, 0.03 weight %, 0.05 weight %, 0.06 weight %, 0.08 weight %, 0.1 weight %, 0.15 weight %, 0.2 weight %, 0.25 weight %, 0.3 weight %, 0.35 weight %, 0.4 weight %, 0.45 weight %, 0.5 weight %.

[0051] According to one embodiment of the present application, based on the total weight of the second reaction system, the second reaction system contains 0.01-5 weight % of the second initiator, for example, 0.1-0.5 weight %, for example, within the numerical range obtained by combining any two of the following numerical values: 0.01 weight %, 0.02 weight %, 0.05 weight %, 0.08 weight %, 0.1 weight %, 0.15 weight %, 0.2 weight %, 0.25 weight %, 0.3 weight %, 0.35 weight %, 0.4 weight %, 0.5 weight %, 0.8 weight %, 1 weight %, 2 weight %, 3 weight %, 4 weight %, 5 weight %.

[0052] According to one embodiment of the present application, the reaction temperature of step 1 is 80-140°C, preferably 90-125°C; the reaction time of step 1 is 30-80 minutes, preferably 40-60 minutes. The reaction temperature of step 2 is 70-150°C, preferably 90-135°C, and the reaction time is 30-120 minutes, preferably 30-60 minutes.

[0053] According to a specific embodiment of the present application, the method of the present invention is carried out in the following manner, using a double-kettle continuous reaction system to carry out step one, and the reaction system includes two reactors. In step one, the first ethylenically unsaturated monomer, the first chain transfer agent, the first modified monomer and the first initiator are mixed, for example, mixed evenly in a mixing kettle, and then transported into a feed kettle, and then continuously transported to the first reactor through a feed pipeline, and then overflowed from the first reactor to the second reactor to continue the reaction, and the temperature of the reactor is controlled at the reaction temperature described above during the whole process. The obtained prepolymer is collected for use in the following step two. According to an embodiment of the present application, the reaction in step one can be carried out under an inert atmosphere, for example, under a nitrogen atmosphere.

[0054] Next, in step 2, the second ethylenically unsaturated monomer, the second chain transfer agent, the second modified monomer, the second initiator, the prepolymer and the polyether polyol are mixed, for example, mixed evenly in a mixing kettle, and then transported into a feed kettle, and then continuously transported to the first reactor through a feed pipeline, and then overflowed from the first reactor to the second reactor to continue the reaction. During the entire process, the temperature of the reactor is controlled at the reaction temperature described above. According to one embodiment of the present application, the reaction in step 2 can be carried out under an inert atmosphere, for example, under a nitrogen atmosphere. The product after the reaction is completed can be subjected to separation and purification steps, such as evaporation, flash evaporation, distillation and the like, to finally obtain the target POP.

[0055] The number average molecular weight of the prepolymer prepared in step 1 of the present invention is 10000-17000, and the volume particle size distribution D[4,3] is 0.2-0.85 microns. The number average molecular weight of the POP finally prepared by the method of the present invention is 50000-80000, and the volume particle size distribution D[4,3] is 1-5.5 microns.

[0056] According to one embodiment of the present application, the POP prepared by the present invention has a viscosity of 3500-4300 mPa·s at 25° C. when the solid content is 40-50 wt %, such as 42-46 wt %, or 44-45 wt %.

[0057] According to one embodiment of the present application, the POP of the present invention can be used as a raw material to react with a polyisocyanate compound to synthesize polyurethane foam. The polyisocyanate can be an aliphatic polyisocyanate, an aromatic polyisocyanate, an oligomer polyisocyanate, a derivative thereof (such as isocyanurate) or a combination thereof.

[0058] The method provided by the present invention can achieve the following beneficial technical effects:

[0059] 1. The present invention adopts a continuous polymerization process (preferably a double-kettle continuous polymerization process) to effectively control the particle size of the prepolymer particles by controlling the ratio of the modified monomer and various other raw materials, and then uses the prepared prepolymer to further polymerize to prepare a polymer polyol with high solid content and low viscosity, thereby achieving good technical effects.

[0060] 2. The method of the present invention adopts specially selected initiators and chain transfer agents to prepare polymer polyols, which not only reduces the viscosity of the product, but also improves the reaction activity of the initiator and the conversion rate of the ethylenically unsaturated monomers, reduces the energy consumption of the subsequent removal of volatile components, and greatly improves the production efficiency.

[0061] The method of the present application is specifically described in the following examples, the purpose of which is to better understand the content of the present application. It should be understood that these examples are merely illustrative and not restrictive. The reagents used in the examples, unless otherwise specified, are conventionally purchased from the market and used directly without further purification. The methods and conditions used in the examples, unless otherwise specified, are conventional methods and conditions.

[0062] Example

[0063] The polyether polyol used in the following examples was purchased from Shandong Bluestar Dongda Co., Ltd. under the trade name DEP-5631D.

[0064] The following examples use Waters' e2695 gel permeation chromatograph (GPC) to characterize the number average molecular weight;

[0065] The viscosity was measured using a DV2T viscometer from Brookfield;

[0066] The samples were centrifuged using a HDC-15K desktop high-speed centrifuge produced by Titan, and then dried using a Vacutherm vacuum oven produced by ThermoFisher to measure the solid content;

[0067] The particle size distribution was characterized using a Mastersizre 3000 laser particle size meter produced by Malvern.

[0068] Other reaction materials and reagents used were of analytical grade and were used directly without further treatment.

[0069] Example 1

[0070] Step 1: First, the prepolymer is prepared by copolymerization. The reaction uses a double-kettle continuous reaction system, which includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reactor and a second reactor, and each reaction device is connected by a pipeline.

[0071] Accurately weigh 71.49g of styrene, 71.49g of acrylonitrile, 486g of isopropanol, 270g of the first modified monomer and 0.72g of initiator (tert-amyl peroxide (2-ethylhexanoate)). The first modified monomer is a polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups made by the inventor, wherein the m-phenylenedimethyl isocyanate content is 3% by weight, the TMI content is 2% by weight, the hydroxyethyl acrylate content is 5% by weight, and the number average molecular weight of the first modified monomer is 15000. The reaction raw materials are pumped into a mixing kettle by a horizontal flow pump, mixed uniformly and cooled to below 5°C, and then the mixed material is pumped into a feed kettle, and then continuously pumped into the first reactor through a feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 60 minutes). The material in the first reactor was allowed to continuously overflow into the second reactor, where the polymerization reaction continued (the residence time was set at 60 minutes). During the entire reaction process, the temperature in the reactor was maintained at 120±5°C, and the entire reaction process was carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). The prepolymer continuously flowing out of the second reactor was collected and tested, and the test results are summarized in Table 1.

[0072] Step 2: The reaction system used in step 2 is the same double-kettle continuous reaction system as in step 1.

[0073] Accurately weigh 512.34 g of styrene, 256.17 g of acrylonitrile, 150 g of the prepolymer prepared in step 1, 4.65 g of initiator, 1.5 g of the second modified monomer, 67.8 g of isopropanol and 867.54 of polyether polyol (DEP-5631D purchased from Shandong Bluestar Dongda Co., Ltd.).

[0074] The second modified monomer is a polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups prepared by the inventor, which is the same as the first modified monomer described in the above step 1. The initiator is tert-amyl peroxy (2-ethylhexanoate).

[0075] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The material in the first reactor continuously overflows into the second reactor, where the polymerization reaction continues to occur (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4~0.5MPa). Subsequently, the material continuously flows into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol was characterized, and the characterization results are listed in Table 1 below. Figure 1 The particle size distribution diagram of the POP prepared in this example is shown.

[0076] Example 2

[0077] Step 1: First, the prepolymer is prepared by copolymerization. The reaction uses a double-kettle continuous reaction system, which includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reactor and a second reactor, and each reaction device is connected by a pipeline.

[0078] Accurately weigh 71.49g of styrene, 71.49g of acrylonitrile, 522g of isopropanol, 234g of the first modified monomer and 0.72g of initiator (tert-amyl peroxy (2-ethylhexanoate)). The first modified monomer is a polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups. The modified polyether polyol is homemade by the inventor and is the same as the first modified monomer used in Example 1. The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 5°C, and then the mixed material is pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 60 minutes). The material in the first reactor is continuously overflowed to the second reactor, and the polymerization reaction continues to occur therein (the residence time is set at 60 minutes). During the whole reaction process, the temperature in the reactor was maintained at 120±5°C, and the whole reaction process was carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). The prepolymer continuously flowing out of the second reactor was collected and tested. The test results are summarized in Table 1.

[0079] Step 2: The reaction system used in step 2 is the same double-kettle continuous reaction system as in step 1.

[0080] Accurately weigh 512.34 g of styrene, 256.17 g of acrylonitrile, 150 g of the prepolymer prepared in step 1, 4.65 g of initiator, 7.5 g of the second modified monomer, 61.8 g of isopropanol and 867.54 of polyether polyol (DEP-5631D purchased from Shandong Bluestar Dongda Co., Ltd.).

[0081] The second modified monomer is a self-made polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups, which is the same as the first modified monomer in this embodiment. The initiator is tert-amyl peroxy (2-ethylhexanoate).

[0082] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The material in the first reactor continuously overflows into the second reactor, where the polymerization reaction continues to occur (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4~0.5MPa). Subsequently, the material continuously flows into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol was characterized, and the characterization results are listed in Table 1 below. Figure 2 The particle size distribution diagram of the POP prepared in this example is shown.

[0083] Example 3

[0084] Step 1: First, the prepolymer is prepared by copolymerization. The reaction uses a double-kettle continuous reaction system, which includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reactor and a second reactor, and each reaction device is connected by a pipeline.

[0085] Accurately weigh 71.49g styrene, 71.49g acrylonitrile, 540g isopropanol, 216g first modified monomer and 0.72g initiator (tert-amyl peroxide (2-ethylhexanoate)). The first modified monomer is a polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups. The modified polyether polyol is homemade by the inventor and is the same as the first modified monomer used in Example 1. The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 5°C, and then the mixed material is pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 60 minutes). The material in the first reactor is continuously overflowed to the second reactor, and the polymerization reaction continues to occur therein (the residence time is set at 60 minutes). During the whole reaction process, the temperature in the reactor was maintained at 120±5°C, and the whole reaction process was carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). The prepolymer continuously flowing out of the second reactor was collected and tested. The test results are summarized in Table 1.

[0086] Step 2: The reaction system used in step 2 is the same double-kettle continuous reaction system as in step 1.

[0087] Accurately weigh 512.34 g of styrene, 256.17 g of acrylonitrile, 150 g of the prepolymer prepared in step 1, 4.65 g of initiator, 10.5 g of the second modified monomer, 58.8 g of isopropanol and 867.54 of polyether polyol.

[0088] The second modified monomer is a homemade polyether polyol modified by m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups, which is the same as the first modified monomer described above in this embodiment. The initiator is tert-amyl peroxide (2-ethylhexanoate). The polyether polyol is DEP-5631D purchased from Shandong Bluestar Dongda Co., Ltd.

[0089] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The material in the first reactor continuously overflows into the second reactor, where the polymerization reaction continues to occur (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4~0.5MPa). Subsequently, the material continuously flows into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol was characterized, and the characterization results are listed in Table 1 below. Figure 3 The particle size distribution diagram of the POP prepared in this example is shown.

[0090] Example 4

[0091] The reaction uses a double-kettle continuous reaction system, which includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reaction kettle and a second reaction kettle, and each reaction device is connected by a pipeline.

[0092] Step 1 is carried out in exactly the same manner as in Example 1.

[0093] Step 2: Accurately weigh 512.34 g of styrene, 256.17 g of acrylonitrile, 150 g of the prepolymer prepared in step 1, 4.65 g of initiator, 10.5 g of the second modified monomer, 58.8 g of isopropanol and 867.54 of polyether polyol.

[0094] The second modified monomer is a polyether polyol modified with m-phenylenedimethyl isocyanate, 3-isopropyl-dimethylbenzyl isocyanate (TMI) and hydroxyethyl acrylate groups. The modified polyether polyol is self-made by the inventor and is the same as the first modified monomer used in Example 1. The initiator is a mixture of tert-amyl peroxide (2-ethylhexanoate) and 1,1-di(tert-amyl peroxy)cyclohexane in a weight ratio of 9:1. The polyether polyol is DEP-5631D purchased from Shandong Bluestar Dongda Company.

[0095] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The materials in the first reactor are continuously overflowed into the second reactor, and the polymerization reaction continues to occur therein (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). Subsequently, the materials continuously flow into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol is characterized, and the characterization results are listed in Table 1 below.

[0096] Comparative Example 1

[0097] In this comparative example 1, a double-kettle continuous reaction system is used, and the reaction system includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reaction kettle and a second reaction kettle, and each reaction device is connected by a pipeline.

[0098] Accurately weigh 528.24 g of styrene, 264.12 g of acrylonitrile, 4.65 g of initiator, 46.5 g of modified monomer, 148.8 g of isopropanol and 867.69 of polyether polyol.

[0099] The modified monomer is the same as the first modified monomer described in Example 1, and the initiator is tert-amyl peroxy (2-ethylhexanoate). The polyether polyol is DEP-5631D purchased from Shandong Bluestar Dongda Company.

[0100] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The materials in the first reactor are continuously overflowed into the second reactor, and the polymerization reaction continues to occur therein (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). Subsequently, the materials continuously flow into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol is characterized, and the characterization results are listed in Table 1 below.

[0101] Comparative Example 2

[0102] In this comparative example 2, a double-kettle continuous reaction system is used. The reaction system includes a horizontal flow pump, a mixing kettle, a feeding kettle, a first reaction kettle and a second reaction kettle. Each reaction device is connected by a pipeline.

[0103] Accurately weigh 528.24 g of styrene, 264.12 g of acrylonitrile, 4.65 g of initiator, 46.5 g of modified monomer, 148.8 g of isopropanol and 867.69 of polyether polyol.

[0104] The modified monomer is the same as the first modified monomer described in Example 1. The initiator is a mixture of tert-amyl peroxy (2-ethylhexanoate) and 1,1-di(tert-amyl peroxy)cyclohexane in a weight ratio of 9:1. The polyether polyol is purchased from Shandong Bluestar Dongda Company under the trade name of DEP-5631D.

[0105] The reaction raw materials are pumped into the mixing kettle by a horizontal flow pump, mixed evenly and cooled to below 10°C, and then the mixed materials are pumped into the feed kettle, and then continuously pumped into the first reactor through the feed pipeline, and a polymerization reaction occurs in the first reactor (the residence time is set at 30 minutes). The materials in the first reactor are continuously overflowed into the second reactor, and the polymerization reaction continues to occur therein (the residence time is set at 30 minutes). During the entire reaction process, the temperature in the first reactor is maintained at 125±5°C, and the temperature in the second reactor is maintained at 130±5°C, and the entire reaction process is carried out under nitrogen protection (nitrogen pressure 0.4-0.5MPa). Subsequently, the materials continuously flow into the demonomerization kettle, and the isopropanol and residual monomers in the product are removed at a temperature of 130-140°C to obtain a polymer polyol. The polymer polyol is characterized, and the characterization results are listed in Table 1 below.

[0106] Table 1: Characterization results of prepolymers / products of Examples 1-4 and Comparative Examples 1-2

[0107]

Claims

1. A stepwise polymerization method for preparing a polymer polyol, the method comprising: include: Step 1: a first polymerization reaction occurs in a first reaction system comprising a first ethylenically unsaturated monomer and a first modifying monomer to form a prepolymer, wherein the first reaction system further comprises a first chain transfer agent and a first initiator; Step 2: a second polymerization reaction occurs in a second reaction system comprising the prepolymer, a second ethylenically unsaturated monomer, a second modified monomer, and a polyether polyol to obtain the polymer polyol, wherein the second reaction system further comprises a second chain transfer agent and a second initiator; The first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are independently selected from one or more of the following: C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, halogenated C4-C22 aliphatic olefins containing at least one carbon-carbon double bond, C6-C22 aromatic olefins containing at least one carbon-carbon double bond, halogenated C6-C22 aromatic olefins containing at least one carbon-carbon double bond, C2-C12 nitrile containing at least one carbon-carbon double bond, C2-C12 carboxylic acid containing at least one carbon-carbon double bond, C2-C12 carboxylic acid (C1-C12) alkyl ester containing at least one carbon-carbon double bond; The second reaction system comprises a polyether polyol having a number average molecular weight of 400-9000; The first modified monomer and the second modified monomer are the same as or different from each other, and are independently a polyether polyol connected with a modified group, and have a number average molecular weight of 2000-20000. The modified group is selected from one or more of the following: a carbon-carbon double bond, a carbon-carbon triple bond.

2. The stepwise polymerization method according to claim 1, It is characterized in that The first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are the same as or different from each other, and are each independently selected from one or more of the following: styrene, methyl styrene, chlorostyrene, (meth)acrylonitrile, (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate and butyl (meth)acrylate.

3. The stepwise polymerization method according to claim 2, It is characterized in that The first ethylenically unsaturated monomer and the second ethylenically unsaturated monomer are both a mixture of styrene and acrylonitrile, and the mass ratio of styrene to acrylonitrile is 80:20 to 20:

80.

4. The stepwise polymerization method according to claim 1, It is characterized in that The first modified monomer and the second modified monomer are the same as or different from each other, and are independently selected from: polyether polyol modified with m-phenylenedimethyl isocyanate, polyether polyol modified with 3-isopropyl-dimethylbenzyl isocyanate (TMI), polyether polyol modified with (meth)acrylate (C1-C6) hydroxyalkyl ester, and polyether polyol modified with glycidyl methacrylate.

5. The stepwise polymerization method according to claim 1, It is characterized in that The first chain transfer agent and the second chain transfer agent are the same as or different from each other, and are independently selected from one or more of the following: isopropanol, n-butanol, tert-butanol, toluene, ethylbenzene, xylene, hexane, ethyl acetate, butyl acetate, mercaptan or dimethylformamide; The first initiator and the second initiator are the same as or different from each other, and are each independently selected from one or more of the following: azobisbutyronitrile (AIBN), dimethyl azobisisobutyrate, benzoyl peroxide, tert-butyl peroxide (2-ethylhexanoate), tert-butyl peroxide diethylacetate, tert-amyl peroxide (2-ethylhexanoate) and 1,1-di(tert-amylperoxy)cyclohexane.

6. The stepwise polymerization method according to claim 1, It is characterized in that Based on the total weight of the first reaction system, the first reaction system comprises 10-40 wt % of a first ethylenically unsaturated monomer, 15-40 wt % of a first modifying monomer, 50-75 wt % of a first chain transfer agent and 0.01-0.5 wt % of a first initiator.

7. The stepwise polymerization method according to claim 1, It is characterized in that Based on the total weight of the second reaction system, the second reaction system comprises 3-20 weight % of a prepolymer, 10-50 weight % of a second ethylenically unsaturated monomer, 1-10 weight % of a second modifying monomer, 3-15 weight % of a second chain transfer agent, 0.01-5 weight % of a second initiator, and 20-60 weight % of a polyether polyol.

8. The stepwise polymerization method according to claim 1, It is characterized in that The volume particle size distribution D[4,3] of the prepolymer is 0.2-0.85 microns, and the volume particle size distribution D[4,3] of the polymer polyol is 1-5.5 microns.

9. A polymer polyol prepared by the method according to any one of claims 1 to 8.

10. A polyurethane material obtained by reacting an isocyanate raw material with an isocyanate-reactive compound. The isocyanate-reactive compound comprises the polymer polyol of claim 9; The isocyanate raw material contains two or more isocyanate groups or modified groups thereof.

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