WO2024065864A1 - Lost foam casting model material foamed by using supercritical carbon dioxide, and preparation method therefor and use thereof - Google Patents

Lost foam casting model material foamed by using supercritical carbon dioxide, and preparation method therefor and use thereof Download PDF

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WO2024065864A1
WO2024065864A1 PCT/CN2022/123966 CN2022123966W WO2024065864A1 WO 2024065864 A1 WO2024065864 A1 WO 2024065864A1 CN 2022123966 W CN2022123966 W CN 2022123966W WO 2024065864 A1 WO2024065864 A1 WO 2024065864A1
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parts
weight
lost foam
foam casting
carbon dioxide
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PCT/CN2022/123966
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French (fr)
Chinese (zh)
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潘敦
秦柳
马文良
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宁波格林美孚新材料科技有限公司
上海百舸科技有限公司
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Publication of WO2024065864A1 publication Critical patent/WO2024065864A1/en

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
    • C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
    • C08J9/122—Hydrogen, oxygen, CO2, nitrogen or noble gases
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C7/00—Patterns; Manufacture thereof so far as not provided for in other classes
    • B22C7/02—Lost patterns
    • B22C7/023—Patterns made from expanded plastic materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/02—Sand moulds or like moulds for shaped castings
    • B22C9/04—Use of lost patterns
    • B22C9/046—Use of patterns which are eliminated by the liquid metal in the mould
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/10—Esters
    • C08F220/12—Esters of monohydric alcohols or phenols
    • C08F220/14—Methyl esters, e.g. methyl (meth)acrylate
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/16—Making expandable particles
    • C08J9/18—Making expandable particles by impregnating polymer particles with the blowing agent
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2203/00—Foams characterized by the expanding agent
    • C08J2203/06—CO2, N2 or noble gases
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2203/00—Foams characterized by the expanding agent
    • C08J2203/08—Supercritical fluid
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2333/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters
    • C08J2333/06—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C08J2333/10—Homopolymers or copolymers of methacrylic acid esters
    • C08J2333/12—Homopolymers or copolymers of methyl methacrylate
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/54—Improvements relating to the production of bulk chemicals using solvents, e.g. supercritical solvents or ionic liquids

Definitions

  • the present application relates to the field of materials for lost foam casting, and in particular to a lost foam casting model material foamed using supercritical carbon dioxide, and a preparation method and application thereof.
  • Lost foam casting is a new casting process developed in recent years and is known as the casting technology of the 21st century.
  • the performance of the mold material is the key factor affecting the quality of the casting.
  • EPS expandable polystyrene
  • US patent application US4790367A discloses an expandable polymethyl methacrylate, which can well solve the above-mentioned problems.
  • Chinese patent CN105199136A uses polymethyl methacrylate to obtain beads with relatively good yield and quality through a two-step process.
  • the two-step process is relatively complicated, requiring reactions to be carried out in two different reaction equipments, and requiring two washings and two dryings.
  • Chinese patent CN103819859A obtains a new lost foam casting mold material with higher foaming performance by copolymerizing styrene monomer, methyl methacrylate monomer and methacrylic acid monomer.
  • styrene monomer methyl methacrylate monomer
  • methacrylic acid monomer methacrylic acid monomer
  • the technical problem to be solved by the present application is how to develop a safe and environmentally friendly foaming agent for preparing lost foam casting model materials.
  • the present application provides a method for preparing a lost foam casting model material using supercritical carbon dioxide foaming, the method comprising the following steps:
  • Step 1 dissolving methyl methacrylate, a first comonomer, an initiator, a dispersant, and a dispersant aid in a first solvent, and polymerizing to obtain a first product,
  • the first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
  • Step 2 After screening the first product, mix it with the second solvent in an autoclave, introduce carbon dioxide into the autoclave, heat the autoclave to 100-130° C., increase the pressure to 8-15 MPa, maintain for 30-60 min, and then evacuate the pressure in the autoclave within 1-30 s, and expand and foam the first product to obtain the lost foam casting mold material foamed with supercritical carbon dioxide.
  • the methyl methacrylate is 100 parts by weight
  • the first comonomer is 1-100 parts by weight
  • the initiator is 0.1-10 parts by weight
  • the dispersant is 0.1-10 parts by weight
  • the co-dispersant is 0.01-1 parts by weight
  • the first solvent is 100-500 parts by weight.
  • the polymerization temperature in step 1 is 50-100°C.
  • step 2 the first product is 100 parts by weight, and the second solution is 100-500 parts by weight.
  • the carbon dioxide in step 2 is 10-50 parts by weight.
  • step 2 is to open a stirrer blade to stir the second solvent and the first product in the autoclave body.
  • the rotation speed of the agitator blade is 80 rad/min.
  • the initiator is selected from at least one of benzoyl peroxide, benzoic acid peroxide, cumene peroxide, azobisisobutyronitrile, tert-butyl peroxycarbonate-2-ethylhexanoate, 1,1-bis(tert-butyl peroxide)-3.3.3-trimethylcyclohexane, tert-butyl peroxybenzoate and dicumyl peroxide.
  • the dispersant is selected from at least one of tricalcium phosphate, polyvinyl alcohol and hydroxycellulose.
  • the dispersant is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate and sodium dodecyl sulfate.
  • the density of the lost foam casting mold material foamed with supercritical carbon dioxide is 0.01-0.03 g/cm 3 .
  • the first product is particulate matter.
  • the lost foam casting mold material foamed with supercritical carbon dioxide is a granular material.
  • the first solvent is water.
  • the second solvent is water.
  • the lost foam casting model comprises a lost foam casting foam model. Furthermore, the lost foam casting foam model is obtained by filling the lost foam casting mold material into a mold and heating it.
  • the heating is steam heating.
  • the present application prepares a lost foam casting model material by using supercritical carbon dioxide, that is, a carbon dioxide fluid whose temperature and pressure are both above its critical point (critical temperature 31.1°C, critical pressure 7.3MPa), as a physical foaming agent.
  • supercritical carbon dioxide has the advantages of being non-toxic, harmless, non-flammable and non-explosive; and the internal pore structure of the particles after carbon dioxide foaming is more dense, uniform and fine, presenting a microporous structure, which can provide the material with better resilience and strength, and is more conducive to the processing and molding of the material.
  • the present application helps to lower the glass transition temperature by adding low glass transition temperature monomers for copolymerization, thereby reducing the temperature and pressure used for supercritical carbon dioxide foaming.
  • FIG1 is a schematic diagram of a process for preparing a lost foam casting model material using supercritical carbon dioxide foaming according to a preferred embodiment of the present application
  • FIG. 2 (a) is a photograph of a lost foam casting model material foamed with supercritical carbon dioxide in a preferred embodiment of the present application, and (b) is a photograph of particles foamed with pentane in a comparative example of the present application;
  • FIG3 is an internal cell structure of a lost foam casting model material foamed with supercritical carbon dioxide in a preferred embodiment of the present application under a 100x microscope;
  • FIG. 4 is the internal cell structure of the granules after pentane foaming in the comparative example of the present application under a microscope at 100 times magnification.
  • One aspect of the present application provides a lost foam casting model material using supercritical carbon dioxide foaming, which is composed of: methyl methacrylate, a first comonomer, wherein the first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate, an initiator, a dispersant, a dispersant aid, and a first solvent.
  • the composition is polymerized, it is obtained by supercritical carbon dioxide foaming in an autoclave.
  • the components of the composition are as follows:
  • a first comonomer selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate;
  • the initiator is selected from at least one of benzoyl peroxide, benzoic acid peroxide, cumene peroxide, azobisisobutyronitrile, tert-butyl peroxycarbonate-2-ethylhexanoate, 1,1-bis(tert-butyl peroxide)-3.3.3-trimethylcyclohexane, tert-butyl perbenzoate and dicumyl peroxide.
  • the dispersant is selected from at least one of tricalcium phosphate, polyvinyl alcohol, and hydroxycellulose.
  • the dispersant is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, and sodium dodecyl sulfate.
  • the first solvent is water.
  • Another aspect of the present application provides a method for preparing a lost foam casting model material using supercritical carbon dioxide foaming. As shown in FIG1 , the preparation process is as follows:
  • Step 1 dissolving methyl methacrylate, a first comonomer, an initiator, a dispersant, and a dispersant aid in a first solvent, and polymerizing to obtain a first product,
  • the first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
  • the first product is polymethacrylate resin particles for lost foam casting
  • Step 2 Screen the first product to make the particle size more uniform, then put it into the autoclave body and mix it with the second solvent, introduce carbon dioxide into the autoclave body to make the pressure in the autoclave body reach 7Mpa, heat the autoclave to 100-130°C, increase the pressure in the autoclave body to 8-15Mpa, maintain it for 30-60min, then evacuate the pressure in the autoclave body within 1-30s, and expand and foam the first product to obtain the lost foam casting mold material using supercritical carbon dioxide foaming.
  • the preparation process of the lost foam casting model material using supercritical carbon dioxide foaming is as follows:
  • Step 1 dissolving 100 parts by weight of methyl methacrylate, 1-100 parts by weight of a first comonomer, 0.1-10 parts by weight of an initiator, 0.1-10 parts by weight of a dispersant, and 0.01-1 parts by weight of a dispersant in 100-500 parts by weight of water, and polymerizing at 50-100° C. to obtain a first product, polymethacrylate resin particles for lost foam casting;
  • Step 2 sieving the polymethacrylate resin particles with a standard sieve, wherein the standard sieve is one of 20-30 mesh, 30-40 mesh, 40-50 mesh, and 50-60 mesh;
  • the resin expands and foams instantly, and the foamed resin particles obtained are the lost foam casting mold materials using supercritical carbon dioxide foaming, and the density is 0.01-0.03g/ cm3 . This is basically consistent with the particle density range obtained by pentane foaming.
  • Yet another aspect of the present application relates to a new lost foam casting mold material prepared by the above method.
  • Yet another aspect of the present application relates to the use of the lost foam casting model material in preparing a lost foam casting model.
  • a lost foam casting foam model is prepared using a lost foam casting model material foamed with supercritical carbon dioxide, and the lost foam casting model material foamed with supercritical carbon dioxide is filled into a mold and then heated with steam to obtain a lost foam casting foam model product.
  • Yet another aspect of the present application relates to a mixture containing the new lost foam casting mold material.
  • the first product was sieved.
  • the first product was sieved.
  • the first product was sieved.
  • the first product was sieved.
  • the first product was sieved.
  • the intermediate product was sieved.
  • a foaming agent a mixture of n-pentane and isopentane in a mass ratio of 1:4, 2.5 parts of a dispersant, tricalcium phosphate, and 0.5 parts of a dispersant, sodium dodecylbenzene sulfonate, were dissolved in 200 parts of water and immersed at 125°C and 1 MPa to obtain expandable beads.
  • the particles foamed with supercritical carbon dioxide obtained in Example 1 are shown in Figure 2 (a), and the particles foamed with pentane obtained in Comparative Example 1 are shown in Figure 2 (b), and it can be seen that their appearances are basically the same.
  • Figure 3 the internal cell structure of the particles foamed with supercritical carbon dioxide is more dense, uniform and fine, presenting a microporous structure (as shown in Figure 3), while the internal cell structure of the particles foamed with pentane is relatively loose, coarse, and uneven (as shown in Figure 4), which is a unique advantage of supercritical carbon dioxide foaming.
  • This microporous structure can provide better resilience and strength for the material, which is more conducive to the processing and molding of the material.
  • the material is cooled and washed with dilute hydrochloric acid, filtered and dried to obtain a pre-foamed polymer material.
  • the obtained pre-foamed polymer material 2 parts of pentane as a foaming agent, 0.5 parts of toluene, and 0.5 parts of zinc stearate as an antistatic agent were added to the foaming device.
  • the foaming was carried out for 6 hours at a pressure of 0.65 MPa in an autoclave, and the temperature was kept for 10 hours. The temperature was lowered, the material was discharged, and the material was washed to obtain expandable polystyrene-methacrylic acid-methyl methacrylate copolymer beads.
  • methyl methacrylate 100 parts by weight of methyl methacrylate, 10 parts by weight of methyl acrylate, 0.1 parts by weight of benzoyl peroxide, 1 part by weight of tricalcium phosphate, and 0.01 parts by weight of sodium dodecylbenzene sulfonate are dissolved in 100 parts by weight of deionized water, polymerized at 75°C to obtain an intermediate product, and then 1 part by weight of n-pentane is added, and expandable beads are obtained by immersion at 130°C and 1 MPa.
  • the pre-expansion ratio and the residue amount (residue amount refers to the residual content of the pre-expansion molding material after burning in the air) of the final product of the embodiment and the comparative example were tested.
  • the test results are shown in Table 1. From the data in Table 1, it can be seen that the foaming performance and residue rate of the product foamed with supercritical carbon dioxide are basically the same as those of the product foamed with pentane. Therefore, the use of supercritical carbon dioxide foaming technology can meet the needs of industrial production, and at the same time greatly improve the safety during production and use, reduce the emission of gases harmful to the environment, and reduce the cost of foaming agents.
  • Example 2 40 ⁇ 1% Example 3 100 ⁇ 1% Example 4 55 ⁇ 1% Example 5 40 ⁇ 1% Comparative Example 1 40 ⁇ 1% Comparative Example 2 51 20%-40% Comparative Example 3 80 ⁇ 1%

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Abstract

A lost foam casting model material foamed by using supercritical carbon dioxide, and a preparation method therefor and a use thereof. The preparation method comprises: first dissolving methyl methacrylate, a first comonomer, an initiator, a dispersing agent, and a co-dispersing agent in a solvent for polymerization to obtain a first product, and then enabling the sieved first product to foam in a high-pressure kettle by using supercritical carbon dioxide to obtain a lost foam casting mold material foamed by using supercritical carbon dioxide. The lost foam casting mold material can be prepared into products such as a lost foam casting foam model.

Description

一种使用超临界二氧化碳发泡的消失模铸造模型材料及其制备方法和应用A lost foam casting model material using supercritical carbon dioxide foaming, and its preparation method and application 技术领域Technical Field
本申请涉及消失模铸模用材料领域，尤其涉及一种使用超临界二氧化碳发泡的消失模铸造模型材料及其制备方法和应用。The present application relates to the field of materials for lost foam casting, and in particular to a lost foam casting model material foamed using supercritical carbon dioxide, and a preparation method and application thereof.
背景技术Background technique
消失模铸造是近年发展起来的新型铸造工艺，被誉为21世纪的铸造技术。在消失模铸造工艺中，铸模材料的性能是影响铸件质量的关键因素。Lost foam casting is a new casting process developed in recent years and is known as the casting technology of the 21st century. In the lost foam casting process, the performance of the mold material is the key factor affecting the quality of the casting.
最早使用的铸模材料是可发性聚苯乙烯(EPS)。但是采用这种铸模材料进行浇注时，存在以下问题：由于EPS热分解比较困难，是一种无序的断裂方式分解，容易产生沥青状物导致铸件表面出现皱纹、冷却结疤、表面凹陷、表面下夹渣等，严重影响铸件质量；另外，EPS还会造成铸件的碳含量偏高，因此对于铸钢件和合金铸钢件的质量影响非常大。The earliest mold material used was expandable polystyrene (EPS). However, there are the following problems when using this mold material for casting: EPS is difficult to thermally decompose and decomposes in a disordered fracture mode, which easily produces asphalt-like substances, causing wrinkles on the surface of the casting, cooling scars, surface depressions, slag inclusions under the surface, etc., which seriously affect the quality of the casting; in addition, EPS will also cause the carbon content of the casting to be too high, so it has a great impact on the quality of steel castings and alloy steel castings.
近年来，一些新型的树脂材料被开发出来用来替代EPS，例如，美国专利申请US4790367A公开了一种可发性聚甲基丙烯酸甲酯，其能够很好地解决上面提到的这些问题。In recent years, some new resin materials have been developed to replace EPS. For example, US patent application US4790367A discloses an expandable polymethyl methacrylate, which can well solve the above-mentioned problems.
中国专利CN1213086C开发了ST-MMA材料。该种材料虽然在理论上是一种比较适合消失模铸造成型的材料，但该材料的发泡条件苛刻而阻碍了其在工业中的应用。其虽然在一定程度上减少了碳残渣等缺陷，然而对于要求较高的合金钢产品还是存在不能忽视的碳缺陷。Chinese patent CN1213086C developed ST-MMA material. Although this material is theoretically more suitable for lost foam casting, its harsh foaming conditions hinder its application in industry. Although it reduces defects such as carbon residue to a certain extent, there are still carbon defects that cannot be ignored for alloy steel products with higher requirements.
中国专利CN105199136A使用聚甲基丙烯酸甲酯，通过两步法获得了产率和质量均较为理想的珠粒。但是，一方面两步法的工艺较繁琐，要在两个不同的反应设备中进行反应，且需要两次清洗和两次干燥。Chinese patent CN105199136A uses polymethyl methacrylate to obtain beads with relatively good yield and quality through a two-step process. However, the two-step process is relatively complicated, requiring reactions to be carried out in two different reaction equipments, and requiring two washings and two dryings.
中国专利CN103819859A通过苯乙烯单体、甲基丙烯酸甲酯单体、甲基丙烯酸单体的共聚获得了较高发泡性能的消失模铸造铸模新材料，但是其仍然不得不使用含苯共聚单体，即苯乙烯单体，因而不可避免地仍然会出现“碳缺陷”问题。Chinese patent CN103819859A obtains a new lost foam casting mold material with higher foaming performance by copolymerizing styrene monomer, methyl methacrylate monomer and methacrylic acid monomer. However, it still has to use a benzene-containing copolymer monomer, i.e., styrene monomer, and thus inevitably still has the problem of "carbon defects".
上述专利都存在一个共同的问题，那就是使用了易燃易爆的烷烃(例如戊烷)来作为物理发泡剂，由于这类发泡剂的使用会在产品的生产和使用过程中带来不容忽视的安全隐患，而且这些烷烃在消失模铸造模型产品使用以后会发生化学变化转变温室效应气体，存在环境污染的隐患。The above patents all have a common problem, that is, they use flammable and explosive alkanes (such as pentane) as physical foaming agents. The use of such foaming agents will bring about significant safety hazards during the production and use of the products. Moreover, these alkanes will undergo chemical changes and transform into greenhouse gases after the lost foam casting model products are used, posing a risk of environmental pollution.
因此，本领域的技术人员致力于开发一种安全环保的发泡剂来制备消失模铸造模 型材料。Therefore, those skilled in the art are committed to developing a safe and environmentally friendly foaming agent to prepare lost foam casting pattern material.
发明内容Summary of the invention
有鉴于现有技术的上述缺陷，本申请所要解决的技术问题是技术问题如何开发一种安全环保的发泡剂制备消失模铸造模型材料。In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present application is how to develop a safe and environmentally friendly foaming agent for preparing lost foam casting model materials.
为实现上述目的，本申请提供了一种使用超临界二氧化碳发泡的消失模铸造模型材料的制备方法，所述方法包括以下步骤：To achieve the above object, the present application provides a method for preparing a lost foam casting model material using supercritical carbon dioxide foaming, the method comprising the following steps:
步骤1、将甲基丙烯酸甲酯、第一共聚单体、引发剂、分散剂、助分散剂溶于第一溶剂中，聚合得到第一产物，Step 1, dissolving methyl methacrylate, a first comonomer, an initiator, a dispersant, and a dispersant aid in a first solvent, and polymerizing to obtain a first product,
所述第一共聚单体选自丙烯酸甲酯、丙烯酸乙酯、丙烯酸丙酯，丙烯酸丁酯，甲基丙烯酸乙酯，甲基丙烯酸丙酯，甲基丙烯酸丁酯中的至少一种，The first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
步骤2、将所述第一产物进行筛分后与第二溶剂放入高压釜体内混合，向所述高压釜体内通入二氧化碳，将所述高压釜加热到100-130℃，压强增加到8-15Mpa，维持30-60min，然后将所述高压釜体内压强在1-30s内排空，所述第一产物膨胀发泡得到所述使用超临界二氧化碳发泡的消失模铸造铸模材料。Step 2: After screening the first product, mix it with the second solvent in an autoclave, introduce carbon dioxide into the autoclave, heat the autoclave to 100-130° C., increase the pressure to 8-15 MPa, maintain for 30-60 min, and then evacuate the pressure in the autoclave within 1-30 s, and expand and foam the first product to obtain the lost foam casting mold material foamed with supercritical carbon dioxide.
进一步地，步骤1所述甲基丙烯酸甲酯为100重量份、所述第一共聚单体为1-100重量份、所述引发剂为0.1-10重量份、所述分散剂为0.1-10重量份、所述助分散剂为0.01-1重量份、所述第一溶剂为100-500重量份。Furthermore, in step 1, the methyl methacrylate is 100 parts by weight, the first comonomer is 1-100 parts by weight, the initiator is 0.1-10 parts by weight, the dispersant is 0.1-10 parts by weight, the co-dispersant is 0.01-1 parts by weight, and the first solvent is 100-500 parts by weight.
进一步地，步骤1所述聚合的温度为50-100℃。Furthermore, the polymerization temperature in step 1 is 50-100°C.
进一步地，步骤2所述第一产物为100重量份，所述第二溶为100-500重量份。Furthermore, in step 2, the first product is 100 parts by weight, and the second solution is 100-500 parts by weight.
进一步地，步骤2所述二氧化碳为10-50重量份。Furthermore, the carbon dioxide in step 2 is 10-50 parts by weight.
进一步地，步骤2所述混合为打开搅拌器叶浆在所述高压釜体内将所述第二溶剂和所述第一产物搅拌。Furthermore, the mixing in step 2 is to open a stirrer blade to stir the second solvent and the first product in the autoclave body.
进一步地，所述搅拌器叶浆的转速为80rad/min。Furthermore, the rotation speed of the agitator blade is 80 rad/min.
进一步地，所述引发剂选自过氧化苯甲酰、过氧化苯甲酸、过氧化异丙苯、偶氮二异丁腈、过氧化碳酸-2-乙基己酸叔丁酯、1,1-双(过氧化叔丁基)-3.3.3-三甲基环己烷、过氧化苯甲酸叔丁酯以及过氧化二异丙苯中的至少一种。Furthermore, the initiator is selected from at least one of benzoyl peroxide, benzoic acid peroxide, cumene peroxide, azobisisobutyronitrile, tert-butyl peroxycarbonate-2-ethylhexanoate, 1,1-bis(tert-butyl peroxide)-3.3.3-trimethylcyclohexane, tert-butyl peroxybenzoate and dicumyl peroxide.
进一步地，所述分散剂选自磷酸三钙、聚乙烯醇、羟基纤维素中的至少一种。Furthermore, the dispersant is selected from at least one of tricalcium phosphate, polyvinyl alcohol and hydroxycellulose.
进一步地，所述助分散剂为十二烷基苯磺酸钠，十二烷基磺酸钠，十二烷基硫酸钠中的至少一种。Furthermore, the dispersant is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate and sodium dodecyl sulfate.
进一步地，所述使用超临界二氧化碳发泡的消失模铸造铸模材料的密度为0.01-0.03g/cm 3。 Furthermore, the density of the lost foam casting mold material foamed with supercritical carbon dioxide is 0.01-0.03 g/cm 3 .
进一步地，所述第一产物为颗粒物。Furthermore, the first product is particulate matter.
进一步地，所述使用超临界二氧化碳发泡的消失模铸造铸模材料为颗粒物。Furthermore, the lost foam casting mold material foamed with supercritical carbon dioxide is a granular material.
进一步地，步骤1中所述第一溶剂为水。Furthermore, in step 1, the first solvent is water.
进一步地，步骤2中所述第二溶剂为水。Furthermore, in step 2, the second solvent is water.
还提供了一种由上述方法制备得到的消失模铸造模型材料。Also provided is a lost foam casting model material prepared by the method.
还提供了一种上述消失模铸造模型材料在制备消失模铸造模型中的应用。Also provided is a use of the lost foam casting model material in preparing a lost foam casting model.
进一步地，所述消失模铸造模型包括消失模铸造泡沫模型。进一步地，所述消失模铸造泡沫模型通过将所述消失模铸造铸模材料充填到模具中加热成型得到。Furthermore, the lost foam casting model comprises a lost foam casting foam model. Furthermore, the lost foam casting foam model is obtained by filling the lost foam casting mold material into a mold and heating it.
进一步地，所述加热为蒸汽加热。Furthermore, the heating is steam heating.
本申请的技术效果如下：The technical effects of this application are as follows:
(1)本申请通过采用超临界二氧化碳，即温度和压力均在其临界点(临界温度31.1℃，临界压力7.3MPa)之上的二氧化碳流体，作为物理发泡剂制备得到了消失模铸造模型材料，超临界二氧化碳具有无毒、无害、不可燃烧和爆炸等优势；并且二氧化碳发泡后的颗粒内部泡孔结构更加致密均匀细小，呈现一种微孔结构，可以为材料提供更好的回弹性和强度，更加有利于该材料的加工成型。(1) The present application prepares a lost foam casting model material by using supercritical carbon dioxide, that is, a carbon dioxide fluid whose temperature and pressure are both above its critical point (critical temperature 31.1°C, critical pressure 7.3MPa), as a physical foaming agent. Supercritical carbon dioxide has the advantages of being non-toxic, harmless, non-flammable and non-explosive; and the internal pore structure of the particles after carbon dioxide foaming is more dense, uniform and fine, presenting a microporous structure, which can provide the material with better resilience and strength, and is more conducive to the processing and molding of the material.
(2)本申请通过加入低玻璃化温度的单体共聚有助于降低玻璃化温度，从而降低超临界二氧化碳发泡使用的温度和压力。(2) The present application helps to lower the glass transition temperature by adding low glass transition temperature monomers for copolymerization, thereby reducing the temperature and pressure used for supercritical carbon dioxide foaming.
以下将结合附图对本申请的构思、具体结构及产生的技术效果作进一步说明，以充分地了解本申请的目的、特征和效果。The concept, specific structure and technical effects of the present application will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present application.
附图说明BRIEF DESCRIPTION OF THE DRAWINGS
图1是本申请的一个较佳实施例的使用超临界二氧化碳发泡的消失模铸造模型材料的制备过程示意图；FIG1 is a schematic diagram of a process for preparing a lost foam casting model material using supercritical carbon dioxide foaming according to a preferred embodiment of the present application;
图2中(a)为本申请的一个较佳实施例的使用超临界二氧化碳发泡的消失模铸造模型材料的照片，(b)为本申请的对比例戊烷发泡后的颗粒物照片；FIG. 2 (a) is a photograph of a lost foam casting model material foamed with supercritical carbon dioxide in a preferred embodiment of the present application, and (b) is a photograph of particles foamed with pentane in a comparative example of the present application;
图3是本申请的一个较佳实施例的使用超临界二氧化碳发泡的消失模铸造模型材料在100倍显微镜下的内部泡孔结构；FIG3 is an internal cell structure of a lost foam casting model material foamed with supercritical carbon dioxide in a preferred embodiment of the present application under a 100x microscope;
图4是本申请的对比例戊烷发泡后的颗粒物在100倍显微镜下的内部泡孔结构。FIG. 4 is the internal cell structure of the granules after pentane foaming in the comparative example of the present application under a microscope at 100 times magnification.
具体实施方式Detailed ways
以下参考说明书附图介绍本申请的多个优选实施例，使其技术内容更加清楚和便于理解。本申请可以通过许多不同形式的实施例来得以体现，本申请的保护范围并非仅限于文中提到的实施例。The following describes several preferred embodiments of the present application with reference to the drawings in the specification, making the technical content clearer and easier to understand. The present application can be embodied in many different forms of embodiments, and the protection scope of the present application is not limited to the embodiments mentioned in the text.
本申请的一个方面，提供一种使用超临界二氧化碳发泡的消失模铸造模型材料，其由：甲基丙烯酸甲酯，第一共聚单体，所述第一共聚单体选自丙烯酸甲酯、丙烯酸乙酯、丙烯酸丙酯，丙烯酸丁酯，甲基丙烯酸乙酯，甲基丙烯酸丙酯，甲基丙烯酸丁酯中的至少一种，引发剂，分散剂，助分散剂，第一溶剂这一组合物聚合后，在高压釜内，通过超临界二氧化碳发泡得到。One aspect of the present application provides a lost foam casting model material using supercritical carbon dioxide foaming, which is composed of: methyl methacrylate, a first comonomer, wherein the first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate, an initiator, a dispersant, a dispersant aid, and a first solvent. After the composition is polymerized, it is obtained by supercritical carbon dioxide foaming in an autoclave.
在一种实施方式中，所述组合物的组分如下：In one embodiment, the components of the composition are as follows:
100重量份的甲基丙烯酸甲酯；100 parts by weight of methyl methacrylate;
1-100重量份的第一共聚单体，所述第一共聚单体选自丙烯酸甲酯、丙烯酸乙酯、丙烯酸丙酯，丙烯酸丁酯，甲基丙烯酸乙酯，甲基丙烯酸丙酯，甲基丙烯酸丁酯中的至少一种；1-100 parts by weight of a first comonomer, wherein the first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate;
0.1-10重量份的引发剂；0.1-10 parts by weight of an initiator;
0.1-10重量份的分散剂；0.1-10 parts by weight of a dispersant;
0.01-1重量份的助分散剂；0.01-1 parts by weight of a dispersant;
以及100-500重量份的第一溶剂。and 100-500 parts by weight of a first solvent.
在一种实施方式中，所述引发剂选自过氧化苯甲酰、过氧化苯甲酸、过氧化异丙苯、偶氮二异丁腈、过氧化碳酸-2-乙基己酸叔丁酯、1,1-双(过氧化叔丁基)-3.3.3-三甲基环己烷、过氧化苯甲酸叔丁酯以及过氧化二异丙苯中的至少一种。In one embodiment, the initiator is selected from at least one of benzoyl peroxide, benzoic acid peroxide, cumene peroxide, azobisisobutyronitrile, tert-butyl peroxycarbonate-2-ethylhexanoate, 1,1-bis(tert-butyl peroxide)-3.3.3-trimethylcyclohexane, tert-butyl perbenzoate and dicumyl peroxide.
在一种实施方式中，所述分散剂选自磷酸三钙、聚乙烯醇、羟基纤维素中的至少一种。In one embodiment, the dispersant is selected from at least one of tricalcium phosphate, polyvinyl alcohol, and hydroxycellulose.
在一种实施方式中，所述助分散剂为十二烷基苯磺酸钠，十二烷基磺酸钠，十二烷基硫酸钠中的至少一种。In one embodiment, the dispersant is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate, and sodium dodecyl sulfate.
在一种实施方式中，所述第一溶剂为水。In one embodiment, the first solvent is water.
本申请的另一方面，提供使用超临界二氧化碳发泡的消失模铸造模型材料的制备方法。如图1所示，制备过程如下：Another aspect of the present application provides a method for preparing a lost foam casting model material using supercritical carbon dioxide foaming. As shown in FIG1 , the preparation process is as follows:
步骤1、将甲基丙烯酸甲酯、第一共聚单体、引发剂、分散剂、助分散剂溶于第一溶剂中，聚合得到第一产物，Step 1, dissolving methyl methacrylate, a first comonomer, an initiator, a dispersant, and a dispersant aid in a first solvent, and polymerizing to obtain a first product,
所述第一共聚单体选自丙烯酸甲酯、丙烯酸乙酯、丙烯酸丙酯，丙烯酸丁酯，甲基丙烯酸乙酯，甲基丙烯酸丙酯，甲基丙烯酸丁酯中的至少一种，The first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
所述第一产物为消失模铸模用的聚甲基丙烯酸酯树脂颗粒；The first product is polymethacrylate resin particles for lost foam casting;
步骤2、将所述第一产物筛分使颗粒大小比较均匀，然后与第二溶剂放入高压釜体内混合，向所述高压釜体内通入二氧化碳，使所述高压釜体内压强达到7Mpa，将所述高压釜加热到100-130℃，使所述高压釜体内压强增加到8-15Mpa，维持30-60min，然后将所述高压釜体内压强在1-30s内排空，所述第一产物膨胀发泡得到所述使用超临界二氧化碳发泡的消失模铸造铸模材料。Step 2: Screen the first product to make the particle size more uniform, then put it into the autoclave body and mix it with the second solvent, introduce carbon dioxide into the autoclave body to make the pressure in the autoclave body reach 7Mpa, heat the autoclave to 100-130°C, increase the pressure in the autoclave body to 8-15Mpa, maintain it for 30-60min, then evacuate the pressure in the autoclave body within 1-30s, and expand and foam the first product to obtain the lost foam casting mold material using supercritical carbon dioxide foaming.
在一种实施方式中使用超临界二氧化碳发泡的消失模铸造模型材料的制备过程如下：In one embodiment, the preparation process of the lost foam casting model material using supercritical carbon dioxide foaming is as follows:
步骤1、将100重量份甲基丙烯酸甲酯、1-100重量份第一共聚单体、0.1-10重量份引发剂、0.1-10重量份分散剂、0.01-1重量份助分散剂溶于100-500重量份水中，在50-100℃下聚合，得到第一产物消失模铸模用的聚甲基丙烯酸酯树脂颗粒；Step 1, dissolving 100 parts by weight of methyl methacrylate, 1-100 parts by weight of a first comonomer, 0.1-10 parts by weight of an initiator, 0.1-10 parts by weight of a dispersant, and 0.01-1 parts by weight of a dispersant in 100-500 parts by weight of water, and polymerizing at 50-100° C. to obtain a first product, polymethacrylate resin particles for lost foam casting;
步骤2、将聚甲基丙烯酸酯树脂颗粒用标准筛网进行筛分，标准筛网为20-30目， 30-40目，40-50目，50-60目中的一种；Step 2, sieving the polymethacrylate resin particles with a standard sieve, wherein the standard sieve is one of 20-30 mesh, 30-40 mesh, 40-50 mesh, and 50-60 mesh;
筛分后，取100重量份与100-500重量份水放入高压釜体内，打开搅拌器叶浆在釜体内将水和树脂充分搅拌，转速为80rad/min，向釜体内通入10-50重量份二氧化碳，使釜体内压强达到7Mpa。然后对釜体加热到100-130℃，釜内压强8-15Mpa，达到预定温度及压力后维持此状态平衡30-60min，然后快速泄压，1-30s将釜体压力排空，树脂瞬间膨胀发泡，得到的发泡树脂颗粒即为使用超临界二氧化碳发泡的消失模铸造铸模材料，密度为0.01-0.03g/cm 3。这和通过戊烷发泡得到颗粒密度范围基本一致。 After screening, 100 parts by weight and 100-500 parts by weight of water are put into the autoclave, the agitator blade is turned on to fully stir the water and resin in the autoclave, the speed is 80rad/min, 10-50 parts by weight of carbon dioxide is introduced into the autoclave to make the pressure in the autoclave reach 7Mpa. Then the autoclave is heated to 100-130°C, the pressure in the autoclave is 8-15Mpa, and after reaching the predetermined temperature and pressure, this state is maintained for 30-60 minutes, and then the pressure is quickly released, and the autoclave pressure is emptied in 1-30 seconds. The resin expands and foams instantly, and the foamed resin particles obtained are the lost foam casting mold materials using supercritical carbon dioxide foaming, and the density is 0.01-0.03g/ cm3 . This is basically consistent with the particle density range obtained by pentane foaming.
本申请的又另一方面，涉及由上述方法制备的消失模铸造铸模新材料。Yet another aspect of the present application relates to a new lost foam casting mold material prepared by the above method.
本申请的又另一方面，涉及所述消失模铸造模型材料在制备消失模铸造模型中的应用。Yet another aspect of the present application relates to the use of the lost foam casting model material in preparing a lost foam casting model.
在一种实施方式中，使用超临界二氧化碳发泡的消失模铸造模型材料制备消失模铸造泡沫模型，将使用超临界二氧化碳发泡的消失模铸造铸模材料充填到模具中经过蒸汽加热成型即可得到消失模铸造泡沫模型制品。In one embodiment, a lost foam casting foam model is prepared using a lost foam casting model material foamed with supercritical carbon dioxide, and the lost foam casting model material foamed with supercritical carbon dioxide is filled into a mold and then heated with steam to obtain a lost foam casting foam model product.
本申请的又另一方面，涉及包含所述消失模铸造铸模新材料的混合物。Yet another aspect of the present application relates to a mixture containing the new lost foam casting mold material.
实施例1Example 1
在常压反应釜中，将100重量份单体甲基丙烯酸甲酯，1重量份丙烯酸甲酯，0.1重量份引发剂过氧化苯甲酰，0.1重量份分散剂磷酸三钙，0.01重量份助分散剂十二烷基苯磺酸钠溶于100重量份水中，在50℃下聚合获得第一产物聚甲基丙烯酸酯树脂颗粒。In a normal pressure reactor, 100 parts by weight of monomer methyl methacrylate, 1 part by weight of methyl acrylate, 0.1 parts by weight of initiator benzoyl peroxide, 0.1 parts by weight of dispersant tricalcium phosphate, and 0.01 parts by weight of dispersant sodium dodecylbenzene sulfonate were dissolved in 100 parts by weight of water, and polymerized at 50° C. to obtain the first product polymethacrylate resin particles.
将该第一产物进行筛分。The first product was sieved.
在高压釜内，将100重量份第一产物分散于100重量份水中，并通入10重量份发泡剂二氧化碳，在100℃和8MPa下维持30min，然后快速泄压，1s内将釜体压力排空，树脂瞬间膨胀发泡，发泡树脂颗粒密度为0.020g/cm 3，发泡倍率50倍。 In an autoclave, 100 parts by weight of the first product are dispersed in 100 parts by weight of water, and 10 parts by weight of carbon dioxide as a blowing agent are introduced. The temperature is maintained at 100°C and 8MPa for 30 minutes, and then the pressure is rapidly released. The autoclave pressure is emptied within 1 second, and the resin expands and foams instantly. The density of the foamed resin particles is 0.020g/ cm3 , and the foaming ratio is 50 times.
实施例2Example 2
在常压反应釜中，将100重量份单体甲基丙烯酸甲酯，100重量份丙烯酸乙酯，10重量份引发剂过氧化苯甲酸，10重量份分散剂氢氧化镁，1重量份助分散剂十二烷基苯磺酸钠溶于500重量份水中，在100℃下聚合获得第一产物聚甲基丙烯酸酯树脂颗粒。In a normal pressure reactor, 100 parts by weight of monomer methyl methacrylate, 100 parts by weight of ethyl acrylate, 10 parts by weight of initiator benzoic acid peroxide, 10 parts by weight of dispersant magnesium hydroxide, and 1 part by weight of auxiliary dispersant sodium dodecylbenzene sulfonate are dissolved in 500 parts by weight of water, and polymerized at 100° C. to obtain the first product polymethacrylate resin particles.
将该第一产物进行筛分。The first product was sieved.
在高压釜内，将100重量份第一产物分散于500重量份水中，并通入50重量份发泡剂二氧化碳，在130℃和15MPa下维持60min，然后快速泄压，30s内将釜体压力排空，树脂瞬间膨胀发泡，发泡树脂颗粒密度为0.025g/cm 3，发泡倍率40倍。 In an autoclave, 100 parts by weight of the first product were dispersed in 500 parts by weight of water, and 50 parts by weight of carbon dioxide as a blowing agent were introduced. The pressure was maintained at 130°C and 15 MPa for 60 minutes, and then the pressure was quickly released. The autoclave pressure was emptied within 30 seconds, and the resin expanded and foamed instantly. The density of the foamed resin particles was 0.025 g/ cm3 , and the foaming ratio was 40 times.
实施例3Example 3
在常压反应釜中，将100重量份单体甲基丙烯酸甲酯，1重量份甲基丙烯酸乙酯，0.5重量份引发剂过氧化异丙苯，0.5重量份分散剂聚乙烯醇，0.01重量份助分散剂十二烷基苯磺酸钠溶于300重量份水中，在75℃下聚合获得第一产物聚甲基丙烯酸酯树脂颗粒。In a normal pressure reactor, 100 parts by weight of monomer methyl methacrylate, 1 part by weight of ethyl methacrylate, 0.5 parts by weight of initiator cumene peroxide, 0.5 parts by weight of dispersant polyvinyl alcohol, and 0.01 parts by weight of dispersant sodium dodecylbenzene sulfonate were dissolved in 300 parts by weight of water, and polymerized at 75° C. to obtain the first product polymethacrylate resin particles.
将该第一产物进行筛分。The first product was sieved.
在高压釜内，将100重量份第一产物分散于200重量份水中，并通入15重量份发泡剂二氧化碳，在125℃和10MPa下维持30min，然后快速泄压，3s内将釜体压力排空，树脂瞬间膨胀发泡，发泡树脂颗粒密度为0.010g/cm 3，发泡倍率100倍。 In an autoclave, 100 parts by weight of the first product were dispersed in 200 parts by weight of water, and 15 parts by weight of carbon dioxide as a blowing agent were introduced. The temperature was maintained at 125°C and 10 MPa for 30 minutes, and then the pressure was rapidly released. The autoclave pressure was emptied within 3 seconds, and the resin expanded and foamed instantly. The density of the foamed resin particles was 0.010 g/cm 3 , and the foaming ratio was 100 times.
实施例4Example 4
在常压反应釜中，将100重量份单体甲基丙烯酸甲酯，1重量份甲基丙烯酸丙酯，0.5重量份引发剂偶氮二异丁腈，0.5重量份分散剂羟基纤维，0.01重量份助分散剂十二烷基苯磺酸钠溶于300重量份水中，在75℃下聚合获得第一产物聚甲基丙烯酸酯树脂颗粒。In a normal pressure reactor, 100 parts by weight of monomer methyl methacrylate, 1 part by weight of propyl methacrylate, 0.5 parts by weight of initiator azobisisobutyronitrile, 0.5 parts by weight of dispersant hydroxy fiber, and 0.01 parts by weight of dispersant sodium dodecylbenzene sulfonate were dissolved in 300 parts by weight of water, and polymerized at 75° C. to obtain the first product polymethacrylate resin particles.
将该第一产物进行筛分。The first product was sieved.
在高压釜内，将100重量份第一产物分散于200重量份水中，并通入20重量份发泡剂二氧化碳，在115℃和10MPa下维持30min，然后快速泄压，3s内将釜体压力排空，树脂瞬间膨胀发泡，发泡树脂颗粒密度为0.018g/cm 3，发泡倍率55倍。 In an autoclave, 100 parts by weight of the first product were dispersed in 200 parts by weight of water, and 20 parts by weight of carbon dioxide as a blowing agent were introduced. The temperature was maintained at 115°C and 10 MPa for 30 minutes, and then the pressure was rapidly released. The autoclave pressure was emptied within 3 seconds, and the resin expanded and foamed instantly. The density of the foamed resin particles was 0.018 g/ cm3 , and the foaming ratio was 55 times.
实施例5Example 5
在常压反应釜中，将100重量份单体甲基丙烯酸甲酯，1重量份甲基丙烯酸丁酯，1重量份引发剂过氧化苯甲酰，2.5重量份分散剂磷酸三钙，0.05重量份助分散剂十二烷基苯磺酸钠溶于600重量份水中，在80℃下聚合获得第一产物聚甲基丙烯酸酯树脂颗粒。In a normal pressure reactor, 100 parts by weight of monomer methyl methacrylate, 1 part by weight of butyl methacrylate, 1 part by weight of initiator benzoyl peroxide, 2.5 parts by weight of dispersant tricalcium phosphate, and 0.05 parts by weight of dispersant sodium dodecylbenzene sulfonate were dissolved in 600 parts by weight of water, and polymerized at 80° C. to obtain the first product polymethacrylate resin particles.
将该第一产物进行筛分。The first product was sieved.
在高压釜内，将100重量份第一产物分散于200重量份水中，并通入20重量份发泡剂二氧化碳，在125℃和15MPa下维持30min，然后快速泄压，3s内将釜体压力排空，树脂瞬间膨胀发泡，发泡树脂颗粒密度为0.025g/cm 3，发泡倍率40倍。 In an autoclave, 100 parts by weight of the first product were dispersed in 200 parts by weight of water, and 20 parts by weight of carbon dioxide as a blowing agent were introduced. The temperature was maintained at 125°C and 15 MPa for 30 minutes, and then the pressure was rapidly released. The autoclave pressure was emptied within 3 seconds, and the resin expanded and foamed instantly. The density of the foamed resin particles was 0.025 g/ cm3 , and the foaming ratio was 40 times.
对比例1Comparative Example 1
在常压反应釜中，将100份单体甲基丙烯酸甲酯，1份引发剂过氧化苯甲酰，2.5份分散剂磷酸三钙，0.05份助分散剂十二烷基苯磺酸钠溶于600份水中，在80度下聚合获得中间产物。In a normal pressure reactor, 100 parts of monomer methyl methacrylate, 1 part of initiator benzoyl peroxide, 2.5 parts of dispersant tricalcium phosphate, and 0.05 parts of dispersant sodium dodecylbenzene sulfonate were dissolved in 600 parts of water and polymerized at 80 degrees to obtain an intermediate product.
将该中间产物进行筛分。The intermediate product was sieved.
在高压釜内，将100份中间产物，7.5份发泡剂：正戊烷与异戊烷的的混合物，质量比为1:4，2.5份分散剂磷酸三钙，0.5份助分散剂十二烷基苯磺酸钠溶于200份水中，在125℃和1MPa下浸渍获得可发性珠粒。In an autoclave, 100 parts of the intermediate product, 7.5 parts of a foaming agent: a mixture of n-pentane and isopentane in a mass ratio of 1:4, 2.5 parts of a dispersant, tricalcium phosphate, and 0.5 parts of a dispersant, sodium dodecylbenzene sulfonate, were dissolved in 200 parts of water and immersed at 125°C and 1 MPa to obtain expandable beads.
实施例1得到的超临界二氧化碳发泡后的颗粒如图2(a)所示，对比例1得到通过戊烷发泡的颗粒如图2(b)所示，可以看到其外观基本相同。通过显微镜观察二者的内部泡孔结构，可以发现超临界二氧化碳发泡后的颗粒内部泡孔结构更加致密均匀细小，呈现一种微孔结构(如图3所示)，而采用戊烷发泡后的颗粒内部泡孔结构比较松散粗大，且不均匀(如图4所示)，这是超临界二氧化碳发泡的独特优势，这种微孔结构可以为材料提供更好的回弹性和强度，更加有利于该材料的加工成型。The particles foamed with supercritical carbon dioxide obtained in Example 1 are shown in Figure 2 (a), and the particles foamed with pentane obtained in Comparative Example 1 are shown in Figure 2 (b), and it can be seen that their appearances are basically the same. By observing the internal cell structures of the two through a microscope, it can be found that the internal cell structure of the particles foamed with supercritical carbon dioxide is more dense, uniform and fine, presenting a microporous structure (as shown in Figure 3), while the internal cell structure of the particles foamed with pentane is relatively loose, coarse, and uneven (as shown in Figure 4), which is a unique advantage of supercritical carbon dioxide foaming. This microporous structure can provide better resilience and strength for the material, which is more conducive to the processing and molding of the material.
对比例2Comparative Example 2
在装有搅拌器和冷凝回流装置的250ml的三口烧瓶中加入120份的蒸馏水、0.7份引发剂过氧化二苯甲酰、1份分散剂聚乙烯醇、5份苯乙烯(ST)单体、10份甲基丙烯酸甲酯(MMA)单体、5份功能单体甲基丙烯酸(MAA)进行悬浮聚合制备成珠粒材料。In a 250 ml three-necked flask equipped with a stirrer and a condensation reflux device, 120 parts of distilled water, 0.7 parts of initiator dibenzoyl peroxide, 1 part of dispersant polyvinyl alcohol, 5 parts of styrene (ST) monomer, 10 parts of methyl methacrylate (MMA) monomer, and 5 parts of functional monomer methacrylic acid (MAA) were added to carry out suspension polymerization to prepare a bead material.
反应完毕后，冷却物料并用稀盐酸进行洗涤、过滤、干燥制得预发泡聚合物材料。After the reaction is completed, the material is cooled and washed with dilute hydrochloric acid, filtered and dried to obtain a pre-foamed polymer material.
在发泡装置中加入所得预发泡聚合物材料、2份的发泡剂戊烷及0.5份的甲苯、0.5份静电防止剂硬脂酸锌。在高压釜中，压力为0.65MPa的条件下发泡6h，保温10h，降温、出料、洗涤，得可发性聚苯乙烯-甲基丙烯酸-甲基丙烯酸甲酯共聚物珠粒。The obtained pre-foamed polymer material, 2 parts of pentane as a foaming agent, 0.5 parts of toluene, and 0.5 parts of zinc stearate as an antistatic agent were added to the foaming device. The foaming was carried out for 6 hours at a pressure of 0.65 MPa in an autoclave, and the temperature was kept for 10 hours. The temperature was lowered, the material was discharged, and the material was washed to obtain expandable polystyrene-methacrylic acid-methyl methacrylate copolymer beads.
对比例3Comparative Example 3
将100重量份的甲基丙烯酸甲酯、10重量份的丙烯酸甲酯、0.1重量份的过氧化苯甲酰、1重量份的磷酸三钙、0.01重量份的十二烷基苯磺酸钠溶于100重量份的去离子水中，在75℃下聚合获得中间产物后，再加入1重量份的正戊烷，在130℃和1MPa下浸渍获得可发性珠粒。100 parts by weight of methyl methacrylate, 10 parts by weight of methyl acrylate, 0.1 parts by weight of benzoyl peroxide, 1 part by weight of tricalcium phosphate, and 0.01 parts by weight of sodium dodecylbenzene sulfonate are dissolved in 100 parts by weight of deionized water, polymerized at 75°C to obtain an intermediate product, and then 1 part by weight of n-pentane is added, and expandable beads are obtained by immersion at 130°C and 1 MPa.
对实施例和对比例最终产物的预发倍率和残渣量(残渣量是指预发成型材料在空气中燃烧后的残含量)进行测试。测试结果见表1。从表1数据可以看出，采用超临界二氧化碳发泡后的产品与采用戊烷发泡后的产品发泡性能和残渣率基本一致，因此采用超临界二氧化碳发泡工艺是能够满足工业生产的需求，同时大大提高了生产和使用过程中的安全性，减少了对环境有危害的气体排放，降低了发泡剂成本。The pre-expansion ratio and the residue amount (residue amount refers to the residual content of the pre-expansion molding material after burning in the air) of the final product of the embodiment and the comparative example were tested. The test results are shown in Table 1. From the data in Table 1, it can be seen that the foaming performance and residue rate of the product foamed with supercritical carbon dioxide are basically the same as those of the product foamed with pentane. Therefore, the use of supercritical carbon dioxide foaming technology can meet the needs of industrial production, and at the same time greatly improve the safety during production and use, reduce the emission of gases harmful to the environment, and reduce the cost of foaming agents.
表1Table 1
例子example 发泡倍率Foaming ratio 残渣量Residue
实施例1Example 1 5050 ＜1％<1%
实施例2Example 2 4040 ＜1％<1%
实施例3Example 3 100100 ＜1％<1%
实施例4Example 4 5555 ＜1％<1%
实施例5Example 5 4040 ＜1％<1%
对比例1Comparative Example 1 4040 ＜1％<1%
对比例2Comparative Example 2 5151 20％-40％20%-40%
对比例3Comparative Example 3 8080 ＜1％<1%
以上详细描述了本申请的较佳具体实施例。应当理解，本领域的普通技术无需创造性劳动就可以根据本申请的构思作出诸多修改和变化。因此，凡本技术领域中技术人员依本申请的构思在现有技术的基础上通过逻辑分析、推理或者有限的实验可以得到的技术方案，皆应在由权利要求书所确定的保护范围内。The preferred specific embodiments of the present application are described in detail above. It should be understood that ordinary technology in the field can make many modifications and changes according to the concept of the present application without creative work. Therefore, any technical solution that can be obtained by a technician in the technical field based on the concept of the present application through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the scope of protection determined by the claims.

Claims (20)

  1. 一种使用超临界二氧化碳发泡的消失模铸造模型材料的制备方法，其中，所述方法包括以下步骤：A method for preparing a lost foam casting model material using supercritical carbon dioxide foaming, wherein the method comprises the following steps:
    步骤1、将甲基丙烯酸甲酯、第一共聚单体、引发剂、分散剂、助分散剂溶于第一溶剂中，聚合得到第一产物，Step 1, dissolving methyl methacrylate, a first comonomer, an initiator, a dispersant, and a dispersant aid in a first solvent, and polymerizing to obtain a first product,
    所述第一共聚单体选自丙烯酸甲酯、丙烯酸乙酯、丙烯酸丙酯，丙烯酸丁酯，甲基丙烯酸乙酯，甲基丙烯酸丙酯，甲基丙烯酸丁酯中的至少一种，The first comonomer is selected from at least one of methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, propyl methacrylate and butyl methacrylate.
    步骤2、将所述第一产物进行筛分后与第二溶剂放入高压釜体内混合，向所述高压釜体内通入二氧化碳，将所述高压釜加热到100-130℃，压强增加到8-15Mpa，维持30-60min，然后将所述高压釜体内压强在1-30s内排空，所述第一产物膨胀发泡得到所述使用超临界二氧化碳发泡的消失模铸造铸模材料。Step 2: After screening the first product, mix it with the second solvent in an autoclave, introduce carbon dioxide into the autoclave, heat the autoclave to 100-130° C., increase the pressure to 8-15 MPa, maintain for 30-60 min, and then evacuate the pressure in the autoclave within 1-30 s, and expand and foam the first product to obtain the lost foam casting mold material foamed with supercritical carbon dioxide.
  2. 如权利要求1所述的方法，其中，步骤1所述甲基丙烯酸甲酯为100重量份、所述第一共聚单体为1-100重量份、所述引发剂为0.1-10重量份、所述分散剂为0.1-10重量份、所述助分散剂为0.01-1重量份、所述第一溶剂为100-500重量份。The method according to claim 1, wherein in step 1, the methyl methacrylate is 100 parts by weight, the first comonomer is 1-100 parts by weight, the initiator is 0.1-10 parts by weight, the dispersant is 0.1-10 parts by weight, the co-dispersant is 0.01-1 parts by weight, and the first solvent is 100-500 parts by weight.
  3. 如权利要求1所述的方法，其中，步骤1所述聚合的温度为50-100℃。The method according to claim 1, wherein the polymerization temperature in step 1 is 50-100°C.
  4. 如权利要求1所述的方法，其中，步骤2所述第一产物为100重量份，所述第二溶为100-500重量份。The method according to claim 1, wherein in step 2, the first product is 100 parts by weight and the second solution is 100-500 parts by weight.
  5. 如权利要求1所述的方法，其中，步骤2所述二氧化碳为10-50重量份。The method according to claim 1, wherein the carbon dioxide in step 2 is 10-50 parts by weight.
  6. 如权利要求1所述的方法，其中，步骤2所述混合为打开搅拌器叶浆在所述高压釜体内将所述第二溶剂和所述第一产物搅拌。The method according to claim 1, wherein the mixing in step 2 is to turn on the agitator blade to stir the second solvent and the first product in the autoclave body.
  7. 如权利要求6所述的方法，其中，所述搅拌器叶浆的转速为80rad/min。The method of claim 6, wherein the rotation speed of the agitator blade is 80 rad/min.
  8. 如权利要求1所述的方法，其中，所述引发剂选自过氧化苯甲酰、过氧化苯甲酸、过氧化异丙苯、偶氮二异丁腈、过氧化碳酸-2-乙基己酸叔丁酯、1,1-双(过氧化叔丁基)-3.3.3-三甲基环己烷、过氧化苯甲酸叔丁酯以及过氧化二异丙苯中的至少一种。The method according to claim 1, wherein the initiator is selected from at least one of benzoyl peroxide, benzoic acid peroxide, cumene peroxide, azobisisobutyronitrile, tert-butyl peroxycarbonate-2-ethylhexanoate, 1,1-bis(tert-butyl peroxide)-3.3.3-trimethylcyclohexane, tert-butyl peroxybenzoate and dicumyl peroxide.
  9. 如权利要求1所述的方法，其中，所述分散剂选自磷酸三钙、聚乙烯醇、羟基纤维素中的至少一种。The method according to claim 1, wherein the dispersant is selected from at least one of tricalcium phosphate, polyvinyl alcohol and hydroxycellulose.
  10. 如权利要求1所述的方法，其中，所述助分散剂为十二烷基苯磺酸钠，十二烷基磺酸钠，十二烷基硫酸钠中的至少一种。The method according to claim 1, wherein the dispersant is at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfonate and sodium dodecyl sulfate.
  11. 如权利要求1所述的方法，其中，所述使用超临界二氧化碳发泡的消失模铸造铸模材料的密度为0.01-0.03g/cm 3。 The method according to claim 1, wherein the density of the lost foam casting mold material foamed with supercritical carbon dioxide is 0.01-0.03 g/cm 3 .
  12. 如权利要求1所述的方法，其中，所述第一产物为颗粒物。The method of claim 1, wherein the first product is particulate matter.
  13. 如权利要求1所述的方法，其中，所述使用超临界二氧化碳发泡的消失模铸造铸模材料为颗粒物。The method according to claim 1, wherein the lost foam casting mold material foamed using supercritical carbon dioxide is a granular material.
  14. 如权利要求1所述的方法，其中，步骤1中所述第一溶剂为水。The method according to claim 1, wherein in step 1, the first solvent is water.
  15. 如权利要求1所述的方法，其中，步骤2中所述第二溶剂为水。The method according to claim 1, wherein in step 2, the second solvent is water.
  16. 一种消失模铸造模型材料，其中，所述消失模铸造模型材料通过权利要求1-15中任一项所述的方法制备得到。A lost foam casting model material, wherein the lost foam casting model material is prepared by the method according to any one of claims 1 to 15.
  17. 如权利要求16所述的消失模铸造模型材料在制备消失模铸造模型中的应用。Use of the lost foam casting model material as claimed in claim 16 in preparing a lost foam casting model.
  18. 如权利要求17所述的应用，其中，所述消失模铸造模型包括消失模铸造泡沫模型。The use according to claim 17, wherein the lost foam casting model comprises a lost foam casting foam model.
  19. 如权利要求18所述的应用，其中，所述消失模铸造泡沫模型通过将所述消失模铸造铸模材料充填到模具中加热成型得到。The use as claimed in claim 18, wherein the lost foam casting foam model is obtained by filling the lost foam casting mold material into a mold and heating it.
  20. 如权利要求19所述的应用，其中，所述加热为蒸汽加热。The use according to claim 19, wherein the heating is steam heating.
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