# US 8,541,517 B2 · Polymer compositions, polymer films and methods and precursors for forming same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,517 B2 - Document ID: US8541517B2 - Status: Granted - Kind: B2 - Application number: 13/045,195 - Filed: 2011-03-10 - Published: 2012-09-13 - Granted: 2013-09-24 - Earliest claimed: 2011-03-10 - Assignees: Battelle Energy Alliance, LLC - Applicants: John R. Klaehn; Eric S. Peterson; Christopher J. Orme - Inventors: John R. Klaehn; Eric S. Peterson; Christopher J. Orme - Web page: https://patentgrep.com/patent/US8541517B2 ## CPC - C08L 79/04: Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors - C08L 61/28: with melamine - Y10T 428/31862: Melamine-aldehyde - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Stable, high performance polymer compositions including polybenzimidazole (PBI) and a melamine-formaldehyde polymer, such as methylated, poly(melamine-co-formaldehyde), for forming structures such as films, fibers and bulky structures. The polymer compositions may be formed by combining polybenzimidazole with the melamine-formaldehyde polymer to form a precursor. The polybenzimidazole may be reacted and/or intertwined with the melamine-formaldehyde polymer to form the polymer composition. For example, a stable, free-standing film having a thickness of, for example, between about 5 μm and about 30 μm may be formed from the polymer composition. Such films may be used as gas separation membranes and may be submerged into water for extended periods without crazing and cracking. The polymer composition may also be used as a coating on substrates, such as metal and ceramics, or may be used for spinning fibers. Precursors for forming such polymer compositions are also disclosed. ## Claims ### Claim 1 A polymer composition, comprising: at least one polybenzimidazole segment; and at least one melamine-formaldehyde polymer segment at least partially intertwined with the at least one polybenzimidazole segment. ### Claim 2 (depends on 1) The polymer composition of claim 1, wherein the at least one melamine-formaldehyde polymer segment comprises at least one methylated, poly(melamine-co-formaldehyde) segment. ### Claim 3 (depends on 1) The polymer composition of claim 1, wherein a concentration of the at least one polybenzimidazole segment within the polymer composition is greater than a concentration of the at least one melamine-formaldehyde polymer segment within the polymer composition. ### Claim 4 (depends on 1) The polymer composition of claim 1, wherein the at least one melamine-formaldehyde polymer segment is bonded to at least a portion of nitrogen atoms of the at least one polybenzimidazole segment. ### Claim 5 (depends on 1) The polymer composition of claim 1, wherein the polymer composition is substantially free of acidic compounds and lithium salts. ### Claim 6 A polymer film, comprising: a film of a polymer composition, the polymer composition comprising: at least one polybenzimidazole segment; and at least one melamine-formaldehyde segment at least partially intertwined with the at least one polybenzimidazole segment. ### Claim 7 (depends on 6) The polymer film of claim 6, wherein a melamine-formaldehyde polymer of the at least one melamine-formaldehyde segment comprises methylated, poly(melamine-co-formaldehyde). ### Claim 8 (depends on 6) The polymer film of claim 6, wherein the film of the polymer composition has a thickness of between about 0.5 μm and about 100 μm. ### Claim 9 (depends on 6) The polymer film of claim 6, wherein the film of the polymer composition has a thickness of between about 5 μm and about 30 μm. ### Claim 10 (depends on 6) The polymer film of claim 6, wherein the film of the polymer composition is substantially flexible. ### Claim 11 (depends on 6) The polymer film of claim 6, wherein the at least one melamine-formaldehyde segment is reacted with at least a portion of nitrogen atoms of the at least one polybenzimidazole segment. ### Claim 12 (depends on 6) The polymer film of claim 6, wherein the film of the polymer composition exhibits substantially increased hydrogen permeability and hydrogen/carbon dioxide separation over time. ### Claim 13 A method for forming a polymer composition, comprising: combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture; and heating the mixture to form a polymer composition, the melamine-formaldehyde polymer at least partially intertwined with the polybenzimidazole. ### Claim 14 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprises forming the mixture comprising less than or equal to about 40% by weight of the melamine-formaldehyde polymer. ### Claim 15 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprises forming the mixture comprising between about 10% by weight and about 20% by weight of the melamine-formaldehyde polymer. ### Claim 16 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprises forming the mixture comprising a ratio of between about 1:1 and about 20:1 of the melamine-formaldehyde polymer to the polybenzimidazole. ### Claim 17 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprises forming the mixture comprising a ratio of between about 2:1 and about 5:1 of the melamine-formaldehyde polymer to the polybenzimidazole. ### Claim 18 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprising forming the mixture consisting of methylated, poly(melamine-co-formaldehyde), the polybenzimidazole, and at least one solvent. ### Claim 19 (depends on 13) The method of claim 13, wherein heating the mixture to form a polymer composition comprises reacting the melamine-formaldehyde polymer with the polybenzimidazole to form the polymer composition. ### Claim 20 (depends on 19) The method of claim 19, wherein reacting the melamine-formaldehyde polymer with the polybenzimidazole to form the polymer composition comprises bonding methylated, poly(melamine-co-formaldehyde) to at least a portion of nitrogen atoms of the polybenzimidazole. ### Claim 21 (depends on 13) The method of claim 13, wherein combining a melamine-formaldehyde polymer and polybenzimidazole to form a mixture comprises: dissolving the polybenzimidazole into a polar, aprotic solvent to form a polybenzimidazole solution; dissolving methylated, poly(melamine-co-formaldehyde) into an organic solvent to form a methylated, poly(melamine-co-formaldehyde) solution; and combining the polybenzimidazole solution and the methylated, poly(melamine-co-formaldehyde) solution to form the mixture. ### Claim 22 (depends on 21) The method of claim 21, further comprising heating the mixture to a temperature of between about 150° C. and about 250° C. to remove the polar, aprotic solvent and the organic solvent.