DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
Applicant’s claim amendments and remarks filed 3/26/2026 are entered and have
been fully considered.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2, 4-6, 8, are rejected under 35 U.S.C. 103 as being unpatentable over GB1500577 to Firestone Tire and Rubber Company as evidenced by the DBNPD Chemical Book Datasheet in view of the article “Cleaner synthesis and systematical characterization of sustainable poly(isosorbide-co-ethylene terephthalate) by environ-benign and highly active catalysts”, by Xin-Gui Li et al, Journal of Cleaner Production, Volume 206, 2019.
Regarding claims 1, 5, Firestone teaches a method of manufacturing a thermoplastic polyester elastomer consisting of step a) glycolyzing scrap PET with an alkylene glycol to form a degraded polymer and then step b) copolymerizing the degraded polymer with a poly(alkylene ether), page 1, lines 83-92. Firestone teaches specifically in examples 1 and 2, page 3 lines 13-65, that scrap PET chips are glycolyzed with ethylene glycol, which reads on claim 5, in the presence of zinc acetate. Then the glycolyzed scrap is polymerized with PTMEG in the presence of a stabilizer N,N’-di(beta-napthyl)-p-phenylene diamine, and antimony trioxide catalyst. The diamine stabilizer is an antioxidant as evidenced by the DBNPD Chemical Book Datasheet, which reads on the claimed antioxidant. The weight percentage of the glycolyzed PET scrap (intermediate product) in example 1 is 66.37 wt.%, which falls within the claimed weight percent range.
Firestone teaches that the glycolyzed PET scrap is partially depolymerized to oligomers, page 2 lines 18-29, and on page 5 lines 1-7, Firestone further teaches that if the glycolysis reaction were to continue until the scrap PET is depolymerized all the way to the monomer, BHET, the properties of the final elastomer would be essentially the same. Although Firestone uses the oligomers in the examples, the claimed BHET intermediate is also anticipated because Firestone explicitly teaches that depolymerizing
to this monomer will also produce the same physical results as the oligomers.
Firestone exemplifies antimony trioxide as the polymerization catalyst but also states that any known condensation catalyst or mixed catalyst system may be used, page 2 lines 81-83.
Li discloses copolyesters formed by the environmentally friendly and less toxic Ti-Mg catalyst, abstract. The Ti-Mg catalyst has higher catalytic activity and is less toxic than the commonly used antimony trioxide, abstract. Li discloses antimony trioxide is highly toxic, is a carcinogen, and produces toxic by-products as a result of the polymerizations it is used in, table 6 page 12 and page 13 first paragraph. The Ti-Mg catalyst system is derived from titanium butoxide, citric acid, and magnesium acetate, page 11, sec. 3.10. The Ti-Mg catalyst produces non-toxic by-products after polymerization, Fig. 9 page 13.
Li and Firestone are analogous to the claimed invention because both are in the field of copolyester synthesis.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have practiced the invention of Firestone but replacing the toxic antimony trioxide condensation catalyst with the benign Ti-Mg catalyst of Li because it is less dangerous to handle, has higher catalytic activity, and will produce a copolyetherester lower in overall toxicity with no toxic by-products.
Regarding claim 2, Firestone teaches in example 1 that the ratio of scrap PET to ethylene glycol for the glycolysis is 1:2, which falls within the claimed range.
Regarding claim 4, Firestone teaches the weight percentage of the PTMEG in example 2 is 33.2 wt.%, which falls within the claimed range.
Regarding claim 6, Firestone exemplifies the PTMEG in example 2, but also states polyoxyethylene glycol (PEG) is also suitable for the elastomer, page 2, line 46.
Regarding claim 8, Firestone exemplifies the diamine antioxidant in an amount of 1.5 g, which is 0.4147 wt.% of the mixture and equals 4,147 ppm.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over GB1500577 to Firestone Tire and Rubber Company in view of the article “Cleaner synthesis and systematical characterization of sustainable poly(isosorbide-co-ethylene terephthalate) by environ-benign and highly active catalysts”, by Xin-Gui Li et al, Journal of Cleaner Production, Volume 206, 2019 further in view of Barnes et al US4605729A.
Regarding claim 9, Firestone modified by Li teaches the invention according to claim 1, as explained above. Firestone further teaches using zinc acetate dihydrate as the glycolysis (alcoholysis) catalyst in example 1 page 3. Firestone is silent as to the use of a titanium, tin, or antimony compound as the alcoholysis catalyst.
Barnes discloses a process for the production of polyetherester polyols comprising reacting dicarboxylic acids with polyoxyalkylene ether polyols, abstract. Barnes further discloses that during the second stage of the process, the modified polyether ester polyols are esterified with diols in the presence of a catalyst, Col. 6 lines 40-55. The preferred esterification catalysts include zinc acetate (another name for zinc acetate dihydrate), tin diacetate, antimony trioxide, and titanium tetrabutylate, Col. 6 lines 50-52. Esterification is a type of alcoholysis and Barnes shows that the titanium, tin, and antimony catalysts are functionally equivalent to zinc acetate for esterification reactions.
Firestone and Barnes are analogous to the claimed invention because both are directed to polyester formation with esterification (alcoholysis) catalysts.
It is prima facie obvious to substitute one material for another to obtain predictable results when both materials provide the same function, in this case as an esterification catalyst.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to practice the invention of modified Firestone substituting the zinc acetate dihydrate catalyst for a titanium, antimony, or tin catalyst in the alcoholysis reaction with the motivation of obtaining the predicable result of a depolymerized polyester because it is a simple substitution of ingredients that have the same purpose and are functional equivalents as disclosed by Barnes.
Response to Arguments
Applicant's arguments filed 3/24/2026 have been fully considered but they are not persuasive.
Applicant has amended claim 1 and cancelled claim 10. The 103 rejection over Dillyraj has been withdrawn due to the amendment of claim 1, Dillyraj exemplifies phosphoric acid as the condensation catalyst and there is no motivation to replace it with a titanium/ magnesium catalyst. The 102 rejection over Firestone has been withdrawn and changed to a 103 rejection in view of Li et al.
In response to applicant’s argument that because Firestone does not mention the titanium or magnesium catalysts then the claims are not obvious over the reference, examiner has changed the rejection to a 103 rejection and combined Li with Firestone. Li discloses that antimony trioxide is a known carcinogen and a toxic catalyst; the Ti-Mg catalyst is environmentally benign, less hazardous, and has higher catalytic activity. Therefore it would have been obvious to one of ordinary skill in the art to replace the toxic antimony trioxide with the environmentally benign Ti-Mg catalyst of Li.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/V.L.S./Examiner, Art Unit 1766
/RANDY P GULAKOWSKI/Supervisory Patent Examiner, Art Unit 1766
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