US4716002A
Expired / Lapsed
US
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Method of producing a flame-retardant acrylic copolymer
Assignee: Japan Exlan Co Ltd
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Filing: 1986-01-28
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Granted: 1987-12-29
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Expires: 2006-01-28
Abstract
Abstract This invention relates to a method of producing a flame-retardant acrylic polymer by polymerizing, in the presence of a radical polymerization initiator, a vinyl monomer containing acrylonitrile in an amount of more than 75 weight %, in an aqueous medium in which is present a halogen-containing polymer latex substantially free from an emulsifier. The acrylic polymer can provide flame-retardant shaped products, especially fibers, which have no problems in the operation of spinning, transparency, gloss, dyed color clearness, etc.
Inventors
- 👤 Masaaki Fujimatsu
- 👤 Toshiyuki Kobashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:47
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/44; C08F259/00; C08F20/00; C08F20/02; C08F20/42; C08F20/44; C08L; C08L33/00; C08L33/18; C08L33/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
130 words
In a method of producing flame-retardant acrylic fibers, which comprises producing an acrylic polymer, dissolving said acrylic polymer in an inorganic solvent to form a spinning solution, spinning said acrylic polymer in said solution into fibers and after-treating said fibers, the improvement wherein said acrylic polymer is produced by polymerizing, at a temperature of 30° to 60° C., a vinyl monomer containing more than 75 weight % of acrylonitrile, in an aqueous medium containing a radical initiator and a halogen-containing polymer latex substantially free from an emulsifier, said latex containing polymer particles of less than 0.5μ stably dispersed therein, wherein the quantity of said latex is such that the quantity of halogen-containing polymer in said latex is 1.5 to 150 weight % based on the weight of said vinyl monomer.
Claim 2
Dependent Claim
130 words
In a method of producing flame-retardant acrylic fibers, which comprises producing an acrylic polymer, dissolving said acrylic polymer in an inorganic solvent to form a spinning solution, spinning said acrylic polymer in said solution into fibers and after-treating said fibers, the improvement wherein said acrylic polymer is produced by polymerizing, at a temperature of 30° to 60° C., a vinyl monomer containing more than 75 weight % of acrylonitrile, in an aqueous medium containing a radical initiator and a halogen-containing polymer latex substantially free from an emulsifier, said latex containing polymer particles of less than 0.5μ stably dispersed therein, wherein the quantity of said latex is such that the quantity of halogen-containing polymer in said latex is 1.5 to 150 weight % based on the weight of said vinyl monomer.
Claim 3
Dependent Claim
29 words
The method as claimed in claim 1 wherein the acrylic polymer contains combined therewith 40-74 weight % of acrylonitrile based on the total quantity of the polymer finally obtained.
Claim 4
Dependent Claim
32 words
The method as claimed in claim 1 wherein the acrylic polymer contains combined therewith more than 15 weight % of halogen atoms based on the total quantity of the polymer finally obtained.
Claim 5
Dependent Claim
28 words
The method as claimed in claim 1 wherein 0.01 to 2.0 weight %, based on the vinyl monomer, of an inorganic salt is present in the aqueous medium.
Claim 6
Dependent Claim
36 words
The method as claimed in claim 1 wherein the vinyl monomer is charged into the polymerization system in a quantity of from 5 to 40 weight % based on the total quantity of the polymerization system.
Claim 7
Dependent Claim
17 words
The method as claimed in claim 1 wherein the polymerization is conducted for 0.5 to 4 hours.
References Cited (Backward Citations)
US2746944A
Cited
US4075075A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-12-28 | 1991-06-29 | 1991-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-28 | 1995-06-29 | 1995-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-28 | 1999-06-29 | 1999-12-29 | $7700.00 | Window Closed / Lapsed |