DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 11/19/2025 has been entered.
Claims 1 and 11-15 are pending as amended on 11/19/2025.
Claims 14 and 15 stand withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim.
Any rejections and/or objections made in the previous Office action and not repeated below are hereby withdrawn. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office Action.
Claim Rejections - 35 USC § 112
Claims 1, 12 and 13 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites a multifunctional amine species:
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, and has been amended to require that “R” contains a tertiary carbon center. Claim 1 further recites that “R” can be a linear hydrocarbon group. However, in view of the amendment to claim 1 requiring “R” to contain a tertiary carbon center, it is no longer possible for “R” to be a linear hydrocarbon group. Because it is not clear how “R” could be a linear hydrocarbon group while also having a tertiary carbon center, the scope of the claim is unclear. The examiner suggests deleting linear hydrocarbon group from the definition of “R.” [Claims 12 and 13 are rejected for the same reason because they depend from claim 1 and fail to remedy the issue.]
Claim Rejections - 35 USC § 103
Claim(s) 1 and 11-13 is/are rejected under 35 U.S.C. 103 as being unpatentable over Christensen et al (WO 2023/212648) in view of in view of Nowak et al (Visually and Infrared Transparent Poly(oxalamide) Films with Mechanical Toughness, ACS Appl. Polym. Mater. 2022, 4, 5027−5034) and Ascend Performance Materials (HexatranTM Product Profile brochure, pp 1-4, Rev 04/2022; downloaded from: https://ascendmaterials-files.sfo2.cdn.digitaloceanspaces.com/files/Brochures/Hexatran_Brochure.pdf on 5/2/2025.
Christensen discloses a polydiketoenamine (PDK) based renewable plastic [0002]. Christensen teaches that the composition for PDK comprises at least one triketone and at least one polyamine. The triketones and polyamines are bound using dynamic covalent diketoenamine bonds, thereby allowing recovery of the monomeric compounds [0027]. Christensen teaches that the system for a PDK which comprises at least one triketone and at least one polyamine functions as a renewable, customizable plastic system with desired functional properties [0027].
Christensen teaches that triketones may be obtained from the condensation of 1,3-diketones (with dimedone named as an example thereof) with dicarboxylic acids (with sebacic acid, forming TK10, named as an example thereof). Christensen teaches that triketones with heteroatoms may change the rate of hydrolysis and depolymerization conditions such as time and temperature [0029-31].
As shown in figure 6 (copied below):
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the triketone formed from reaction of diketone with dicarboxylic acid, as taught by Christensen, is a triketone dimer and therefore corresponds to (a) as presently recited.
[As to the presently elected triketone dimer species, DK10, a triketone TK10 obtained from dimedone as the 1,3-diketone, as taught by Christensen, has a structure according to the instant elected (a) species DK-10, as recited in instant claims 12 and 13, wherein R is a 10-carbon linear hydrocarbon group. It would have been obvious to the person having ordinary skill in the art to have formed PDK from TK10 as the triketone monomer, as taught by Christensen, by selecting any 1,3-diketone for the reaction with sebacic acid to form the triketone, including dimedone, in order to obtain a PDK with a desired rate of hydrolysis and depolymerization.]
Christensen further teaches that the polyamine building block may comprise any polyamine that can form a diketoenamine bond with triketone, and that examples of possible polyamines include linear and/or branched diamines, also polyamines such as triamine [0032]. Christensen teaches that diamines act as chain extenders to the triamine crosslinkers, and that chain extenders increase elongation to break and toughness of the network [0081] (see also [00142] teaching an embodiment of PDK comprising a triamine that acts as a crosslinking agent). The polyamine formulation (various functionality, di and tri series, molecular weight) can increase toughness and elongation to break, create tunable Tg, tunable rheology, and increase thermal stability [0083]. Christensen names several examples of polyamines with various chemical structure, including diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), which are polyamines containing primary and secondary amine groups, and including tris(aminomethyl)ethane (TAME), which is a triamine containing three primary amine groups and no secondary or tertiary amine groups [0032].
While the TAME named by Christensen meets the presently claimed requirement regarding the absence of secondary or tertiary amine groups, TAME has a quaternary (not a tertiary) carbon within the hydrocarbon group, and, TAME has five carbons (which is not within the claimed range of 8 to 20). Christensen fails to name a triamine crosslinker meeting all of the requirements of the presently recited multifunctional amine species. Christensen further fails to teach PDK formed from 4-(aminomethyl)octane-1,8-diamine (the elected multifunctional amine species, recited in instant claim 11) as the crosslinking triamine.
As set forth in the Ascend product brochure, 4-(aminomethyl)octane-1,8-diamine), “Hexatran,” was known in the art as a trifunctional primary amine with equal or better performance compared to other amines (TEPA, TETA and DETA) typically used in high-performance applications. Ascend teaches that Hexatran has a high boiling point, low vapor pressure and low to no smell and color, and that its unique trifunctional structure provides toughness, flexibility and high cross-linking density (p 2). Ascend shows that a coating made with Hexatran has superior flexibility with no cracking compared to products made with DETA or TETA (p 3). Nowak also discloses the use of Hexatran, a commercially available trifunctional primary amine with aliphatic interior, as a crosslinker for preparing poly(oxalamide) from aliphatic amine monomers and dioxalate. See p 5029 and abstract on p 5027.
Considering Christensen’s teachings in [0081-83], particularly that the polyamine formulation (various functionality, di and tri series, molecular weight) can increase toughness and elongation to break, create tunable Tg, tunable rheology, and increase thermal stability, the person having ordinary skill in the art would have recognized that several properties of a PDK depend on its chemical structure. Additionally, considering that Christensen’s disclosed list in [0032] of example polyamine building blocks for PDK includes a variety of types of chemical structures, one having ordinary skill in the art would have had a reasonable expectation of success in varying the structure of the polyamine reactant in order to tune the properties of a PDK product. Therefore, when forming a PDK from TK10 and a triamine as a cross-linker, as taught by Christensen, the person having ordinary skill in the art would have been motivated to select a known triamine crosslinker having any appropriate structure in order to tune the properties of the PDK for a specific application, with a reasonable expectation of success.
Considering the disclosures regarding Hexatran in Nowak and Ascend, the person having ordinary skill in the art would have been motivated to select 4-(aminomethyl)octane-1,8-diamine) as a triamine crosslinker in order to provide a material having toughness, flexibility and high cross-linking density, and, in order to provide equal to or better performance compared to the typically used amines (e.g., DETA, TETA, TEPA). One would have been further motivated to select Hexatran as a polyamine crosslinker in view of Ascend’s teaching that it has low/no smell and color. It would have been obvious to the person having ordinary skill in the art, therefore, to have formed a PDK network from TK10 and triamine crosslinker, as taught by Christensen, by utilizing 4-(aminomethyl)octane-1,8-diamine) (i.e., Hexatran, as described in both Nowak and Ascend) instead of a typically used amine as taught by Christensen (e.g., DETA, TETA, TEPA), thereby arriving at a vitrimeric PDK network as presently recited.
Response to Arguments
Applicant's arguments filed 11/19/2025 have been fully considered.
Applicant argues (p 6) that the Examiner has asserted that Applicant needs to show an unexpected difference, and implies that this contradicts the Examiner’s recognition that different materials will exhibit different properties. Applicant argues that it is ambiguous what actually needs to be shown as unexpected.
General guidance with regard to showing unexpected results can be found in MPEP 716.02. At minimum, Applicant’s allegation of unexpected results must be supported by a comparison of the claimed subject matter with the closest prior art, as discussed in MPEP 716.02(e). While the instant specification contains some examples of Hexatran-based poly(diketoenamine) films subject to depolymerization and/or degradation, there are no comparative examples of depolymerization/degradation of films which are representative of the closest prior art.
As acknowledged by Applicant (arguments p 6), the expected properties of a material based on its chemical structure can be determined based on, e.g., known-structure property relationships and chemistry modeling software. Additionally, as previously noted, the existence of structure-property relationships within PDK materials, including a dependence of hydrolysis/depolymerization on heteroatoms, is specifically recognized by Christensen (see, e.g., [0029-31]: Christensen teaches that triketones with heteroatoms may change the rate of hydrolysis and depolymerization conditions such as time and temperature). As set forth in MPEP 716.02(b), evidence relied upon should establish that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance. Considering that one having ordinary skill in the art would have expected the degradation rate of a PDK formed from TREN to differ from the degradation rate of a structurally different PDK formed from a different polyamine (such as a PDK formed from Hexatran), Applicant must establish that whatever differences in properties might exist between PDK’s of differing chemical structures (i.e., PDK as claimed and PDK which is representative of the closest prior art) would have been regarded as unexpected and of both statistical and practical significance.
NOTE: if Applicant provides a comparison of the claimed subject matter and closest prior art which is considered to show evidence of nonobviousness, the evidence must additionally be evaluated to determine if it is commensurate in scope with the claims which the evidence is offered to support. See MPEP 716.02(d). Applicant must provide sufficient evidence to show that unexpected results would be obtained for all species encompassed by the present claims in order to overcome the present rejection by showing unexpected results.
On p 8 of the remarks, Applicant questions why one having ordinary skill in the art would have modified the combination of references to arrive at the material recited in claim 1 (without any hindsight). Applicant’s argument has been fully considered, however, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). In the present case, every limitation of the present claims is addressed with citations to the prior art. The rejection does not rely upon any knowledge gleaned only from Applicants' disclosure. Therefore, the examiner submits that Applicants have not demonstrated that the present rejection employs improper hindsight.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL KAHN whose telephone number is (571)270-7346. The examiner can normally be reached Monday to Friday, 8-5.
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/RACHEL KAHN/Primary Examiner, Art Unit 1766