Expandable acrylic resin bead, expanded acrylic resin bead, and expanded acrylic resin beads molded article
US-2018030233-A1 · Feb 1, 2018 · US
Expandable methyl methacrylate resin particles, methyl methacrylate resin pre-expanded particles, methyl methacrylate expansion-molded body, and method for producing expandable methyl methacrylate resin particles
US12338337B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-12338337-B2 |
| Application number | US-202117487136-A |
| Country | US |
| Kind code | B2 |
| Filing date | Sep 28, 2021 |
| Priority date | Mar 29, 2019 |
| Publication date | Jun 24, 2025 |
| Grant date | Jun 24, 2025 |
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- Title
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- Abstract
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Abstract
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Expandable methyl methacrylate resin particles having a narrow particle size distribution, a good yield, and excellent expandability and formability are provided. The expandable methyl methacrylate resin particles include a base resin containing, as constitutional units, a certain amount of a methyl methacrylate unit and a certain amount of acrylic ester unit, and a blowing agent. The expandable methyl methacrylate resin particles have an average particle diameter of 0.6 mm to 1.0 mm and a particle diameter variation coefficient of not more than 20%.
First claim
Opening claim text (preview).
The invention claimed is: 1. A method for producing expandable methyl methacrylate resin particles, comprising the steps of: (a) copolymerizing monomers including a methyl methacrylate monomer and an acrylic ester monomer to obtain a copolymer; and (b) impregnating a blowing agent in the copolymer thus obtained, wherein in the step (a), an amount of the methyl methacrylate monomer to be added is not less than 91 parts by weight and not more than 99 parts by weight and an amount of the acrylic ester monomer to be added is not less than 1 part by weight and not more than 9 parts by weight, relative to 100 parts by weight of a total amount of the methyl methacrylate monomer and the acrylic ester monomer to be added, and in the step (a), the monomers are added to an aqueous medium to initiate a polymerization reaction of the monomers, the aqueous medium containing a poorly water-soluble inorganic salt in an amount of not less than 0.08 parts by weight and not more than 0.20 parts by weight relative to 100 parts by weight of the monomers, and at a timing when a polymerization conversion rate is not less than 35% and not more than 70%, the poorly water-soluble inorganic salt is added thereto in an amount of not less than 0.08 parts by weight and not more than 0.50 parts by weight relative to 100 parts by weight of the monomers, and the expandable methyl methacrylate resin particles have an average particle diameter of 0.6 mm to 1.0 mm. 2. The method as set forth in claim 1 for producing the expandable methyl methacrylate resin particles, wherein the monomers further include a bifunctional monomer, and an amount of the bifunctional monomer to be added is not less than 0.05 parts by weight and not more than 0.15 parts by weight, relative to 100 parts by weight of the total amount of the methyl methacrylate monomer and the acrylic ester monomer to be added. 3. The method as set forth in claim 1 for producing the expandable methyl methacrylate resin particles, wherein the acrylic ester monomer is butyl acrylate.
Assignees
Inventors
Classifications
Homopolymers or copolymers of methyl methacrylate · CPC title
Homopolymers or copolymers of acrylic acid esters · CPC title
Hydrocarbons · CPC title
Methyl esters {, e.g. methyl (meth)acrylate} · CPC title
- B22C7/023Primary
Patterns made from expanded plastic materials · CPC title
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Frequently asked questions
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- What does patent US12338337B2 cover?
- Expandable methyl methacrylate resin particles having a narrow particle size distribution, a good yield, and excellent expandability and formability are provided. The expandable methyl methacrylate resin particles include a base resin containing, as constitutional units, a certain amount of a methyl methacrylate unit and a certain amount of acrylic ester unit, and a blowing agent. The expandabl…
- Who is the assignee on this patent?
- Kaneka Corp
- What technology area does this patent fall under?
- Primary CPC classification B22C7/023. Mapped technology areas include Operations & Transport.
- When was this patent published?
- Publication date Tue Jun 24 2025 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 3 related publications on this page (citations in our corpus or others sharing the same primary CPC).