CN112280289A - Polyurethane material based on modified alumina filler and preparation method thereof - Google Patents
Polyurethane material based on modified alumina filler and preparation method thereof Download PDFInfo
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- CN112280289A CN112280289A CN202011179995.4A CN202011179995A CN112280289A CN 112280289 A CN112280289 A CN 112280289A CN 202011179995 A CN202011179995 A CN 202011179995A CN 112280289 A CN112280289 A CN 112280289A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K9/00—Use of pretreated ingredients
- C08K9/02—Ingredients treated with inorganic substances
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K13/00—Use of mixtures of ingredients not covered by one single of the preceding main groups, each of these compounds being essential
- C08K13/06—Pretreated ingredients and ingredients covered by the main groups C08K3/00 - C08K7/00
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/02—Elements
- C08K3/04—Carbon
- C08K3/042—Graphene or derivatives, e.g. graphene oxides
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2227—Oxides; Hydroxides of metals of aluminium
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/011—Nanostructured additives
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
Abstract
The scheme relates to a polyurethane material based on a modified alumina filler and a pouring method thereof, and the polyurethane material comprises, by weight, 30-50 parts of a polyurethane prepolymer, 10-40 parts of a filler, 3-5 parts of a curing agent and 5-15 parts of a plasticizer; the filler is graphene modified nano alumina and is prepared by carrying out esterification reaction on acidified graphene and nano alumina. According to the preparation method provided by the invention, the graphene modified nano-alumina is used as the filler and added into the polyurethane, and the layered structure of the graphene enables the filler and the resin to be mixed more fully; the process provided by the invention has simple steps, stable performance of the casting resin and uniform material in the preparation process, and is suitable for casting operation; the prepared polyurethane casting material has high temperature resistance and excellent tensile strength performance.
Description
Technical Field
The invention belongs to the technical field of casting resin, and particularly relates to a polyurethane material based on a modified alumina filler and a preparation method thereof.
Background
Epoxy resin-based casting resins have a long pot life and are often used for weaving parts of medium and large volumes, while polyurethane-based casting resins have a short pot life, and therefore these casting resins are used for small-volume molded parts, and the existing casting materials have high brittleness after curing, low impact resistance, and improved electrical and thermal conductivity due to more components. Alumina (Al)2O3) The conventional alumina is used as a filler directly, and when the conventional alumina is used as the filler, the alumina can be layered with resin to cause internal nonuniformity, voids in the interior and on the surface and the like.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to ensure that the filler alumina can be mixed with resin more fully and uniformly by modifying the filler alumina.
In order to achieve the purpose, the invention provides the following technical scheme:
a polyurethane material based on modified alumina filler comprises, by weight, 30-50 parts of polyurethane prepolymer, 10-40 parts of filler, 3-5 parts of curing agent and 5-15 parts of plasticizer; the filler is graphene modified nano alumina, and the graphene modified nano alumina is prepared by the following steps:
1) graphene pretreatment: placing graphene in a mixed solution of sulfuric acid and nitric acid for ultrasonic dispersion, refluxing for 4 hours at 80 ℃, and drying and grinding after the reaction is finished;
2) adding the pretreated graphene in the step 1) into ethanol, performing ultrasonic dispersion, adding nano-alumina, rapidly stirring at 25-35 ℃ to fully react, centrifuging, washing with absolute ethyl alcohol for a plurality of times, performing vacuum drying, and grinding to obtain graphene modified nano-alumina.
Further, the mass fraction of the graphene is 1% -5% of that of the aluminum oxide.
Further, the preparation method of the polyurethane prepolymer comprises the following steps: adding polymer polyol into a reaction kettle, stirring, heating and vacuum dehydrating; and cooling, adding isocyanate, and continuing heating to react to obtain the isocyanate-terminated polyurethane prepolymer.
Further, the polymer polyol is hydroxyl-terminated polybutadiene; the isocyanate is toluene diisocyanate or diphenylmethane diisocyanate.
Further, the temperature of vacuum dehydration is 90-120 ℃, the dehydration time is 1-3h, the temperature is reduced to 40-70 ℃, isocyanate is added, the temperature is raised to 70-100 ℃, and the reaction is carried out for 1.5-4 h.
Further, the curing agent is aromatic diamine; the plasticizer is one or a mixture of dibutyl phthalate, diethyl phthalate, dioctyl adipate and dibutyl adipate.
The invention further provides a process for preparing a polyurethane material based on a modified alumina filler as defined in any one of the preceding claims, comprising the following steps: weighing the polyurethane prepolymer, the filler and the plasticizer according to the formula ratio, uniformly stirring, adding the curing agent, and uniformly stirring; and then pouring, vulcanizing and molding, and demolding to obtain the polyurethane material.
Furthermore, the temperature of the vulcanization molding is 90-120 ℃, and the time is 0.5-1 h.
The graphene is a new material with a single-layer two-dimensional honeycomb lattice structure formed by tightly stacking carbon atoms, and has excellent optical, mechanical and electrical properties. After the graphene is acidified, the surface of the graphene can be oxidized into carboxyl, the surface of the nano alumina particle has a plurality of hydroxyls, and the hydroxyls on the surface of the nano alumina and the carboxyls on the surface of the acidified graphene can be used for similar esterification reaction, so that the graphene modified nano alumina is obtained, the problem that the graphene is easy to agglomerate is solved, and meanwhile, a modified alumina layer-shaped structure can be endowed, and when the graphene modified nano alumina is used as a filler, the graphene modified nano alumina can be fully mixed with resin.
Compared with the prior art, the invention has the beneficial effects that: according to the preparation method provided by the invention, the graphene modified nano-alumina is used as the filler and added into the polyurethane, and the layered structure of the graphene enables the filler and the resin to be mixed more fully; the process provided by the invention has simple steps, stable performance of the casting resin and uniform material in the preparation process, and is suitable for casting operation; the prepared polyurethane casting material has high temperature resistance and excellent tensile strength performance.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Examples
A polyurethane material based on modified alumina filler comprises, by weight, 30-50 parts of polyurethane prepolymer, 10-40 parts of filler, 3-5 parts of curing agent and 5-15 parts of plasticizer; the filler is graphene modified nano alumina, and the graphene modified nano alumina is prepared by the following steps:
1) graphene pretreatment: placing graphene in a mixed solution of sulfuric acid and nitric acid for ultrasonic dispersion, refluxing for 4 hours at 80 ℃, and drying and grinding after the reaction is finished;
2) adding the pretreated graphene in the step 1) into ethanol, performing ultrasonic dispersion, adding nano-alumina, rapidly stirring at 25-35 ℃ to fully react, centrifuging, washing with absolute ethyl alcohol for a plurality of times, performing vacuum drying, and grinding to obtain graphene modified nano-alumina.
Further, the mass fraction of the graphene is 1% -5% of that of the aluminum oxide.
Further, the preparation method of the polyurethane prepolymer comprises the following steps: adding polymer polyol into a reaction kettle, stirring, heating and vacuum dehydrating; and cooling, adding isocyanate, and continuing heating to react to obtain the isocyanate-terminated polyurethane prepolymer.
Further, the polymer polyol is hydroxyl-terminated polybutadiene; the isocyanate is toluene diisocyanate or diphenylmethane diisocyanate.
Further, the temperature of vacuum dehydration is 90-120 ℃, the dehydration time is 1-3h, the temperature is reduced to 40-70 ℃, isocyanate is added, the temperature is raised to 70-100 ℃, and the reaction is carried out for 1.5-4 h.
Further, the curing agent is an aromatic diamine, preferably E-330; the plasticizer is one or a mixture of several of dibutyl phthalate, diethyl phthalate, dioctyl adipate and dibutyl adipate, and is preferably a mixture of dibutyl phthalate and dibutyl adipate.
A process for preparing a polyurethane material based on a modified alumina filler as defined in any one of the preceding claims, comprising the following steps: weighing the polyurethane prepolymer, the filler and the plasticizer according to the formula ratio, uniformly stirring, adding the curing agent, and uniformly stirring; and then pouring, vulcanizing and molding, and demolding to obtain the polyurethane material.
Furthermore, the temperature of the vulcanization molding is 90-120 ℃, and the time is 0.5-1 h.
Example 1: 30 parts of polyurethane prepolymer, 10 parts of filler (graphene modified nano-alumina), 3 parts of curing agent and 5 parts of plasticizer, wherein in the preparation process of the graphene modified nano-alumina, the mass fraction of graphene is 1% of that of alumina.
Example 2: 40 parts of polyurethane prepolymer, 20 parts of filler (graphene modified nano-alumina), 3 parts of curing agent and 7 parts of plasticizer, wherein in the preparation process of the graphene modified nano-alumina, the mass fraction of graphene is 2% of that of alumina.
Example 3: 50 parts of polyurethane prepolymer, 30 parts of filler (graphene modified nano-alumina), 4 parts of curing agent and 10 parts of plasticizer, wherein in the preparation process of the graphene modified nano-alumina, the mass fraction of graphene is 4% of that of alumina.
Comparative example: the raw materials and the preparation process are the same as those in the example, and the raw material ratio is the same as that in the example 3.
Comparative example 1: except that the modified alumina was replaced with normal alumina.
Comparative example 2: the difference is that the modified alumina is replaced by common alumina and graphene.
The polyurethane materials of examples 1 to 3 and comparative examples 1 to 2 were subjected to the performance test, and the results are shown in Table 1.
TABLE 1
As can be seen from the data in the table, the polyurethane materials with uniform material and better tensile property and high temperature resistance are successfully prepared in the embodiments 1-3 of the invention. Comparative example 1 is a method of using common alumina as a filler to cast a polyurethane material, wherein the filler and the polyurethane are not sufficiently mixed in the casting process, so that the material is slightly layered, and various corresponding performances are reduced; in comparative example 2, two components of graphene modified alumina are added into polyurethane separately, and due to the large specific surface area of graphene, the graphene is directly added into the polyurethane together with alumina as a filler without treatment, so that the graphene is agglomerated, and the material is layered, and even voids are generated inside and on the surface.
While embodiments of the invention have been disclosed above, it is not limited to the applications listed in the description and the embodiments, which are fully applicable in all kinds of fields of application of the invention, and further modifications may readily be effected by those skilled in the art, so that the invention is not limited to the specific details without departing from the general concept defined by the claims and the scope of equivalents.
Claims (8)
1. A polyurethane material based on modified alumina filler is characterized by comprising 30-50 parts of polyurethane prepolymer, 10-40 parts of filler, 3-5 parts of curing agent and 5-15 parts of plasticizer in parts by weight; the filler is graphene modified nano alumina, and the graphene modified nano alumina is prepared by the following steps:
1) graphene pretreatment: placing graphene in a mixed solution of sulfuric acid and nitric acid for ultrasonic dispersion, refluxing for 4 hours at 80 ℃, and drying and grinding after the reaction is finished;
2) adding the pretreated graphene in the step 1) into ethanol, performing ultrasonic dispersion, adding nano-alumina, rapidly stirring at 25-35 ℃ to fully react, centrifuging, washing with absolute ethyl alcohol for a plurality of times, performing vacuum drying, and grinding to obtain graphene modified nano-alumina.
2. The modified alumina filler-based polyurethane material of claim 1, wherein the graphene is present in an amount of 1% to 5% by weight of the alumina.
3. The modified alumina filler-based polyurethane material of claim 1, wherein the polyurethane prepolymer is prepared by the steps of: adding polymer polyol into a reaction kettle, stirring, heating and vacuum dehydrating; and cooling, adding isocyanate, and continuing heating to react to obtain the isocyanate-terminated polyurethane prepolymer.
4. The modified alumina filler-based polyurethane material of claim 3, wherein the polymer polyol is hydroxyl-terminated polybutadiene; the isocyanate is toluene diisocyanate or diphenylmethane diisocyanate.
5. The method for preparing a polyurethane material based on a modified alumina filler according to claim 3, wherein the temperature of the vacuum dehydration is 90-120 ℃, the dehydration time is 1-3h, the temperature is reduced to 40-70 ℃, the temperature is increased to 70-100 ℃ after the isocyanate is added, and the reaction is carried out for 1.5-4 h.
6. The modified alumina filler-based polyurethane material of claim 1, wherein the curing agent is an aromatic diamine; the plasticizer is one or a mixture of dibutyl phthalate, diethyl phthalate, dioctyl adipate and dibutyl adipate.
7. A process for preparing a polyurethane material based on a modified alumina filler according to any one of claims 1 to 6, characterized in that it comprises the following steps: weighing the polyurethane prepolymer, the filler and the plasticizer according to the formula ratio, uniformly stirring, adding the curing agent, and uniformly stirring; and then pouring, vulcanizing and molding, and demolding to obtain the polyurethane material.
8. The process for the preparation of a polyurethane material based on modified alumina fillers according to claim 7, characterized in that the temperature of the vulcanization molding is between 90 and 120 ℃ and the time is between 0.5 and 1 hour.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202011179995.4A CN112280289A (en) | 2020-10-29 | 2020-10-29 | Polyurethane material based on modified alumina filler and preparation method thereof |
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Application publication date: 20210129 |