# US 5,352,764 A · Stepwise linear magnetic polymers and methods for preparation thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,352,764 A - Document ID: US5352764A - Status: Granted - Kind: A - Application number: 08/144,163 - Filed: 1993-10-26 - Granted: 1994-10-04 - Earliest claimed: 1992-04-10 - Assignees: Northrop Corporation - Inventors: Jack D. Mackey - Web page: https://patentgrep.com/patent/US5352764A ## CPC - C08G 73/0672: {with only one nitrogen atom in the ring} - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS ## Abstract A stepwise linear polymer composition having intense magnetic properties and a method for preparation of same. A phthalimide compound and an aromatic dialiphatic acid are reacted in the presence of an acetate of monovalent metal at elevated temperatures to form a phenylenebis diphthalimidine compound. The phenylenebis diphthalimidine compound is then reacted with 3-benzylidine phthalimidine and a metal salt of an aliphatic acid at elevated temperatures under an inert gas to form the intensely magnetic polymer. The reactions may be carried out in the presence of a solvent. ## Claims ### Claim 1 A process for producing a stepwise linear polymer composition having intense magnetic properties, comprising the steps of: reacting a phthalimide compound with 1,3-phenylene diacetic acid, in a proportion of about two molar amounts of the phthalimide compound to about one molar amount of the 1,3-phenylene diacetic acid, in the presence of an acetate of a monovalent metal at a temperature of between about 200.degree. to about 260.degree. C. for between about forty-five minutes to about 3 hours, whereby a 1,3-phenylenebis diphthalimidine compound is formed; cooling, solidifying, and extracting the 1,3-phenylene-bis diphthalimidine compound; pulverizing, filtering, and washing the extracted 1,3-phenylenebis diphthalimidine compound; and, reacting the extracted 1,3-phenylenebis diphthalimidine compound, a metal acetate salt selected from the group consisting of metal acetate salts of a divalent metal and metal acetate salts of a trivalent metal, and 3-benzylidine phthalimidine at a temperature of between about 260.degree. and about 380.degree. C. under an inert gas atmosphere, whereby the polymer composition having intense magnetic properties is formed. ### Claim 2 (depends on 1) A process as claimed in claim 1, wherein the phthalimide compound is phthalimide. ### Claim 3 (depends on 1) A process as claimed in claim 1, wherein the acetate of a monovalent metal is sodium acetate. ### Claim 4 A process for producing a stepwise linear polymer composition having intense magnetic properties, comprising the steps of: reacting a phthalimide compound with 1,3-phenylene diacetic acid, in a proportion of about two molar amounts of the phthalimide compound to about one molar amount of the 1,3-phenylene diacetic acid, in the presence of an acetate of a monovalent metal at a temperature of between about 200.degree. to about 260.degree. C. for between about forty-five minutes to about 3 hours, whereby a 1,3-phenylenebis diphthalimidine compound is formed; cooling, solidifying, and extracting the 1,3-phenylene-bis diphthalimidine compound; pulverizing, filtering, and washing the extracted 1,3-phenylenebis diphthalimidine compound; and, reacting the extracted 1,3-phenylenebis diphthalimidine compound with a metal acetate salt selected from the group consisting of metal acetate salts of a monovalent metal and with a salt of a polyvalent metal and with 3-benzylidine phthalimidine at a temperature of between about 260.degree. and about 380.degree. C. under an inert gas atmosphere, whereby the polymer composition having intense magnetic properties is formed. ### Claim 5 (depends on 4) A process as claimed in claim 4, wherein the metal acetate salt is sodium acetate. ### Claim 6 (depends on 4) A process as claimed in claim 4, wherein the salt of a polyvalent metal is ferrous oxylate. ### Claim 7 (depends on 1) A process as claimed in claim 1, wherein the metal acetate salt is selected from the group consisting of acetate salts of a divalent metal. ### Claim 8 (depends on 7) A process as claimed in claim 7, wherein the metal acetate salt is a metal acetate salt selected from the group consisting of nickel acetate, iron acetate, cobalt acetate, manganese acetate, and chromium acetate. ### Claim 9 (depends on 1) The process as claim in claim 1, wherein the metal acetate salt is selected from the group consisting of acetate salts of a trivalent metal. ### Claim 10 (depends on 9) The process as claimed in claim 9, wherein the metal acetate salt is ferric acetate. ### Claim 11 (depends on 1) The process as claimed in claim 1, wherein the second reacting step further comprises reacting the 1,3-phenylenebis diphthalimidine compound, the metal acetate salt, and the 3-benzylidine phthalimidine in a solvent. ### Claim 12 (depends on 11) The process as claimed in claim 11, wherein the solvent is a solvent selected from the group consisting of N-methylpyrolidinone and dimethylformamide. ### Claim 13 A stepwise linear polymer composition having the recurring structure ##STR17## wherein M is a metal selected from the group consisting of divalent metals and trivalent metals. ### Claim 14 (depends on 13) A polymer composition as claimed in claim 13, wherein the metal is selected from the group consisting of nickel, iron, cobalt, manganese, and chromium.