DETAILED ACTION
Status of claim rejections
The rejection of record under 35 USC 112(d) is withdrawn in view of Applicant’s cancellation of claim 30 in the response filed 03/26/2026.
The rejections of record under 35 USC 103 are maintained in view of Applicant’s arguments in the response filed 03/26/2026.
Maintained Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
First rejection
Claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 are rejected under 35 U.S.C. 103 as being unpatentable over Bartels et al (WO 2017201482 A1; published 23 November 2017; hereinafter “Bartels”; prior art of record) as evidenced by Takagishi et al (Journal of Polymer Science, Polymer Chemistry Edition, Vol. 23, 2109-2116 (1985); prior art of record), in view of Porter et al (Biomimetic Materials by Freeze Casting. JOM 65, 720–727 (2013)), Nakano et al (US 20070029256 A1; published 08 February 2007; hereinafter “Nakano”; prior art of record) and Yang et al (J. Mater. Chem., 2011, 21, 2783-2811; hereinafter “Yang”; prior art of record) as evidenced by Li et al (JZ. Mater. Chem. C, 2013, 1,7695; hereinafter “Li”).
Bartels teaches a crosslinked graphene based composite membrane (a composite comprising a macroporous scaffold providing structural support as in claim 1) (see abstract). The water permeable membrane comprises a porous support, a crosslinked graphene oxide (GO) composite layer, the porous support is polyvinylidene fluoride (PVDF) (a semicrystalline structural polymer as in claim 1) (see claim 1 and 23; paragraph 0083) and includes a polymer such as polyethylenimine (PEI) (a plurality of functional polymer particle as in claim 1) (see paragraph 0086). The graphene oxide compound, the crosslinker, and/or additives are chemically bound to any combination of each other to result in a material matrix (polymer matrix as in claim 1; structural and functional polymers interspersed to form polymer matrix as in claim 1) (paragraph 0036, 0047, 0077, and 0080).
Bartels does not explicitly teach that the macroporous scaffold comprises a freeze-cast material.
However, Porter teaches creation of biomimetic materials by freeze casting (see title, abstract). Porter teaches freeze casting is a relatively simple, inexpensive, and adaptable technique to fabricate bulk porous scaffolds and hybrid composites (pg. 720, col 1, paragraph 2). Porter also teaches that freeze casting is commonly used to form a variety of polymeric, metallic, ceramic, and composite materials with excellent microstructural control when liquid slurry containing ceramic powders (a freeze-cast material as in claim 1) and a freezing vehicle (e.g., water) is mixed with a dispersant (e.g., surfactant) and binder (e.g., long-chain polymer), which aid in colloid dispersion and green body integrity, respectively (Fig. 1a). Second, the liquid slurry is poured into a mold and frozen (Fig. 1b). During solidification, particles are pushed between and trapped within the freezing vehicle as it forms columnar channels of frozen solvent crystals. Third, the frozen sample is lyophilized (or freeze dried) to sublimate the frozen liquid phase (Fig. 1c). The resulting pores of the freeze-cast scaffolds after freeze drying are direct replicas of the frozen ice crystals (pg. 720, col 2). Porter also teaches that the polymers are impregnated and infiltrated into the porous scaffolds (pg. 720, col 2, paragraph 2; see Fig. 1(e)), and that the use of materials such as alumina-polymethylmethacrylate in freeze-cast ceramic scaffolds promotes strong covalent bonding between phases of ceramic and polymer scaffolds to protect against interfacial shear and delamination (polymer particles covalently attached directly or indirectly to a surface of the pores as in claim 1) (pg. 724, col 2). Porter further teaches micrographs of scaffolds (see Fig. 1(f)-(g) reproduced below), which shows the pores oriented along vertical and horizontal axes (i.e., oriented along a primary axis as in claim 1).
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Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the scaffold of Bartels by using the freeze-casting techniques and materials as taught by Porter to arrive at the claimed invention. As Porter teaches known techniques to create various freeze-cast bulk porous scaffolds and hybrid composites, one of ordinary skill would have been motivated to use freeze-casting materials with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Porter explicitly teaches that freeze casting is an advantageously simple, inexpensive, and adaptable technique to fabricate porous scaffolds and composites, allows for impregnation and infiltration of polymers into the porous scaffolds, and strong covalent bonding between phases of ceramic and polymer scaffolds to protect against interfacial shear and delamination.
Neither Bartels nor Porter explicitly teaches the scaffold comprises through-pores.
However, Nakano teaches a composite porous membrane (see title abstract), where the surface of the porous membrane has an opening ratio between 10% and 90%, an average pore diameter D (μm) of 0.1≦D≦50, a standard deviation σd (μm) of pore diameter of 0≦σd/D≦0.6, and the percentage of through-pores to all the pores of the porous membrane of 30% or more (comprises through-pores as in claim 1) (see claim 1). Nakano teaches that when used for separation, the membrane has pore size and pore size uniformity features necessary for efficiently capturing and separating cells, and high opening ratio that enables rapid filtration (see paragraph 0006-0009).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels and Porter and include through-pores as taught by Nakano to arrive at the claimed invention. As Nakano teaches composite membranes that have through-pores, one of ordinary skill would have been motivated to make the modification with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Nakano teaches that composite membranes having such through-pore features has pore size and pore size uniformity features necessary for efficiently capturing and separating cells, and high opening ratio that enables rapid filtration.
The difference between the references and the instant claims is that none of the references explicitly teach the functional polymer particle is crosslinked and a gel (as in claim 1).
However, Yang teaches composites of functional polymeric hydrogels and porous membranes (title). Yang teaches polymeric hydrogels are an interesting class of ‘‘soft matter’’ with several established and many more possible applications as functional materials, and the combination of rigid porous membrane with a functional hydrogel (gel as in claim 1) enables functionality of the hydrogel (pg. 2784, col 1 paragraph 1). Yang also teaches that hydrogels contain macromolecular network architectures; they are insoluble due to presence of chemical and physical crosslinks or physical entanglements, and possess the ability to absorb large amounts of water and swell (see pg. 2785, col 2, paragraph 6 and Fig. 3). Yang teaches that various porous membrane adsorbers, including macroporous membranes can be made with hydrogels and base membranes such as PVDF (see, for example, pg. 2790, Table 2; col 1-2 and Fig. 6). Yang teaches several advantageous features of hydrogels within composite membranes, including selective ad(b)sorption, anti-fouling, pore-filling/-narrowing, stimuli-response and serving as biocompatible/-active layer (pg. 2790, col 1, paragraph 1; pg. 2794; col 1, paragraph 2).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels, Porter, and Nakano with the functional hydrogel of Yang to arrive at the claimed invention. As Yang teaches that hydrogels can be used in composite membranes, one of ordinary skill would have been motivated to make the modification with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Yang teaches that hydrogels advantageously contain macromolecular network architectures that allow for selective ad(b)sorption, anti-fouling, pore-filling/-narrowing, stimuli-response and serving as biocompatible/bio-active layer.
Regarding claim 2, 7, and 40, Yang teaches use of functional gels/hydrogels (see above).
Further regarding claim 40, neither Bartels, Porter, Nagano nor Yang explicitly teach that the structural polymer (such as PVDF) is insoluble in a solvent capable of swelling the gel. However, Li evidences that water is a non-solvent for PVDF (i.e., PVDF is insoluble in water) (see pg. 7695, col 2, paragraph 1). As such, absent evidence to the contrary, the PVDF of Bartels and Yang is insoluble in a solvent capable of swelling the hydrogel of Yang.
Regarding claims 3 and 12, Bartels does not explicitly teach that the functional polymer comprises at least one primary amine, primary ammonium, etc. (see claim 3), or that the functional polymer particle has a functional group capable of binding to a peptide, glycoprotein, barium, zinc, chromium, etc. (see claim 12). However, Takagishi evidences that PEI polymer contains 25% primary amines, 50% secondary amines, and 25% tertiary amines, where the primary and secondary amines are capable of binding divalent metal ions such as Cu2+, Ni2+, Co2+ and Zn2+ (see synopsis; pg. 2110, paragraph 1; pg. 2111, Table 1). As such, absent evidence to the contrary, the PEI as taught by Bartels also has the claimed properties of having at least one primary amine and a functional group capable of binding (for example) zinc. "Products of identical chemical composition cannot have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present (see MPEP 2112.01(II)).
Regarding claim 6, Nakano teaches that the through-pores have a diameter between 0.1 D and 50 D, in which the claimed diameter in claim 6 overlaps or lies within. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990) (see MPEP 2144.05(I)).
Regarding claim 8, Bartels teaches that the polymer particle can be polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG), polyethylene oxide (PEO), polyoxyethylene (POE), polyacrylic acid (PAA), polymethacrylic acid (PMMA) and polyacrylamide (PAM), polyethylenimine (PEI), poly(2-oxazoline), polyethersulfone (PES), methyl cellulose (MC), chitosan, poly (allylamine hydrochloride) (PAH), or poly (sodium 4-styrene sulfonate) (PSS), of combinations thereof (see above).
Regarding claim 26, Porter teaches the use of materials such as alumina-polymethylmethacrylate (i.e., a polymer) in freeze-cast ceramic scaffolds promotes strong covalent bonding between phases of ceramic and polymer scaffolds to protect against interfacial shear and delamination (polymer particles covalently attached directly or indirectly to a surface of the pores via a polymer separate from the functional polymer particles and the structural polymer as in claim 26).
Regarding claim 32, Bartels teaches the membrane comprises graphene, Porter teaches ceramic (a macroporous scaffold), and Bartels also teaches that the support can be a polymer such as polyamide (Nylon), polyimide (PI), polyvinylidene fluoride (PVDF), polyethylene (PE), polyethylene terephthalate (PET), polysulfone (PSF), polyether sulfone (PES) (paragraph 0083).
Further regarding claim 40, neither Bartels, Porter, Nagano nor Yang explicitly teach that the structural polymer (such as PVDF) is insoluble in a solvent capable of swelling the gel. However, Li evidences that water is a non-solvent for PVDF (i.e., PVDF is insoluble in water) (see pg. 7695, col 2, paragraph 1). As such, absent evidence to the contrary, the PVDF of Bartels and Yang is insoluble in a solvent capable of swelling the hydrogel of Yang.
Regarding claim 41, Bartels teaches the polymer can be polyvinylidene fluoride (PVDF), polyethylene (PE), polyethylene terephthalate (PET), polysulfone (PSF), polyether sulfone (PES), and/or any mixtures thereof (see paragraph 0083).
Regarding claim 59, Porter teaches the use of materials such as alumina-polymethylmethacrylate in freeze-cast ceramic scaffolds promotes strong covalent bonding between phases of ceramic and polymer scaffolds to protect against interfacial shear and delamination (polymer particles covalently attached directly or indirectly to a surface of the pores as in claim 59) (pg. 724, col 2).
Regarding claim 61, Yang teaches various functional hydrogel composited with diameters of 3-5 um (see Fig. 7).
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Second rejection
Claim 20 and 60 are rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Chang et al (WO 2016043808 A1; published 26 March 2016, cited in Applicant IDS; hereinafter “Chang”).
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach that the functional polymer particle is crosslinked from a crosslinker comprising structures (7), (8), (9), (10), or (12) or any combination thereof, wherein each of L1-L7 is a leaving group, X is a counterion, each of R1 and R2 independently is hydrogen or a C1-C6 alkyl; n is an integer from 2-50, m is an integer from 0-20, and p is an integer from 1-9.
However, Chang teaches high-capacity anion exchange material (title) using polymeric beads and crosslinked polyamines (see abstract; claim 1) where the polyamine is linear polyethyleneimine and branched polyethyleneimine (see claim 33; paragraph 0081) and use of various crosslinking agents (see claims). Specifically, Chang teaches that the amine-reacting crosslinking agents include compounds such as small molecules, oligomers, or polymers having at least two functional groups (i.e., di- or multi-functional groups), such as a halogen group, epoxy group, ester group, a Michael acceptor, and combinations thereof (paragraph 0091) and shows various suitable crosslinking agents to form functionalized crosslinked polyamines (see image below reproduced from claim 35 of Chang; also paragraphs 0123-124). Chang discloses various crosslinkers that read on claimed structures (7), (8), (9), (10), and (12) (as in claim 20). Please note that the selection of a known material based on its suitability for its intended use supports a prima facie obviousness determination; see, for example, Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945) or In re Leshin, 277 F.2d 197, 125 USPQ 416 (CCPA 1960) (MPEP 2144.07). As such, one of ordinary skill would have been free to choose a crosslinking agent for the purposes of creating crosslinked polyamine for use in a chromatography exchange material with a reasonable expectation of success.
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Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels, Porter, Nakano and Yang and use the crosslinking agents as taught by Chang to arrive at the claimed invention. As Chang teaches crosslinkers that can be utilized in chromatography materials, one of ordinary skill would have been motivated to make the modification with reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Chang teaches various crosslinking agents that can be used to successfully create functionalized crosslinked polyamines.
Regarding claim 60, Chang explicitly teaches crosslinking density is the percentage of mole of crosslinking agent per mole of nitrogen in the polyamine and is generally dependent on the ratio of crosslinking agent to polyamine in the discrete phase and represents the theoretical number of linking points between polyamine present (see paragraph 0108). While Chang does not explicitly teach the crosslinking density of 0.01 to 0.8 as instantly claimed, the crosslinking density would have been the result of routine optimization of standard laboratory techniques available at the time of filing, as Chang teaches that the crosslinking density is dependent on ratio (i.e., the amount) of crosslinking agent to the polyamine used (see MPEP 2144.05). One of ordinary skill would have been motivated to vary the amount of crosslinking agent to polyamine to achieve a desired crosslinking density.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Third rejection
Claim 29 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Jiang and Sun (Environ Sci Technol. 2011 May 1;45(9):4003-9; prior art of record).
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach that the functional polymer particle and/or structural polymer is indirectly attached to a surface of the pores (as in claim 29).
However, Jiang teaches ion-exchange chromatography is a widely used technique in the bio-separations, including protein downstream processing, because of the use of solvent conditions that do not affect large amounts of protein denaturation (pg. 201, col 1, paragraph 2). Jiang also teaches amine-rich polymer, polyethylenimine (PEI), has been widely used in the chemical modifications of chromatography stationary phases for anion exchange (AEX) separation due to its low-cost and easy availability ((pg. 201, col 1, paragraph 2). When PEI is adsorbed onto inorganic supports such as silica, zirconia, graphite, or hydroxyapatite and crosslinked, it can be used for chromatography (pg. 201, col 1, paragraph 2). When used on organic supports, PEI is reacted with surface anchor groups and covalently bound onto the surface of the support (functional polymer indirectly attached to surface of pores as in claim 29 in part).
None of the references teach the functional polymer particle and/or structural polymer is crosslinked to PEI; and the PEI is crosslinked to a functional group on the surface of the pores.
However, Sun teaches the creation of a hyperbranched PEI membrane that induced crosslinking on a polyamide-imide (PAI) porous hollow fiber support (see abstract; see Figure 2). The cross-linking of polyamides with polyethyleneimine (PEI) is a promising approach to prepare a positively charged membrane by introducing additional amine group on membrane surface (pg. 4004, col 1, paragraph 2). When hyperbranched PEI (functional polymer as in claim 29) was used as modification agent and a crosslinking solution was made by dissolving hyperbranched PEI in 2-propanol and water before it was flowed through the hollow fiber material (functional polymer crosslinked to PEI as in claim 29) (see pg. 4004 col 2). Sun also teaches that the PAI membrane surface was also crosslinked to the different PEI polymers (PEI crosslinked to the surface of the pores as in claim 29) allowing for adsorption of pharmaceutical compounds (see pg. 4005, col 2; Fig. 2, and col 2).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite membrane of Bartels, Porter, Nakano, and Yang with the covalent attachment of PEI to the membrane surface as taught by Jiang and crosslink the polymer to PEI and crosslink PEI to the porous surface as taught by Sun to arrive at the claimed invention. As Sun teaches crosslinking of hyperbranched PEI polymers to a porous fiber material for adsorption of compounds, one of ordinary skill would have been motivated to make the modifications with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Jiang teaches PEI is widely used in the chemical modifications of chromatography stationary phases for chromatography and that PEI can advantageously be reacted with surface anchor groups and covalently bound onto the surface of the support and Sun teaches that PEI polymers can successfully be crosslinked and used as a promising approach to prepare a positively charged membrane by introducing additional amine group on membrane surface.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Fourth rejection
Claim 33 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Lu (Materials Science and Engineering R 97 (2015) 23–49; prior art of record).
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach the macroporous scaffold comprises the ceramic or inorganic glass, and the ceramic or inorganic glass comprises silicon oxycarbide.
However, Lu teaches that porous and high surface area materials have important applications as sensors, chemical reactors, electrodes, gas storage media, molecular sieves, membrane supports, lightweight structural materials, thermal insulators, bioimplants, among others (see pg. 24, col 1, paragraph 1). Lu teaches that SiOC (silica oxycarbide as in claim 33) porous materials are such a unique system that can be produced from a large variety of polysiloxane (PSO) precursors and a wide range of processing conditions (pg. 24, col 1, paragraph 1). Lu further teaches that SiOC ceramics, prepared from preceramic polymer routes, can be thermochemically stable up to 1200 8C in air, and do not show compositional or microstructural changes after fairly extended periods of time at elevated temperatures, have good oxidation resistance, possess a low coefficient of thermal expansion, and exhibit good mechanical strength, creep resistance, as well as resistance to corrosion (pg. 24, col 1, paragraph 2).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite membrane of Bartels, Porter, Nakano, and Yang by using silica oxycarbide ceramic as taught by Lu to arrive at the claimed invention. As the claimed invention relies on creation of a composite with a macroporous scaffold, one of ordinary skill would have been motivated to perform a simple substitution of one known element (the graphene scaffold of Bartel or ceramic scaffold of Porter) for another (the silica oxycarbide ceramic of Lu) with a reasonable expectation of success. One of ordinary skill would have been motivated to make the substitution because Lu teaches that SiOC ceramics are advantageously thermochemically stable up to 1200 8C in air, and do not show compositional or microstructural changes after fairly extended periods of time at elevated temperatures, have good oxidation resistance, possess a low coefficient of thermal expansion, and exhibit good mechanical strength, creep resistance, as well as resistance to corrosion.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Fifth rejection
Claim 36 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59, and 61 above, and further in view of Firstov et al (Powder Metallurgy Progress, Vol.1 (2001), No 1; hereinafter “Firstov”; prior art of record).
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, and 59 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach the macroporous scaffold comprises a pore volume fraction of 10% to 70% of the composite.
However, Firstov (in the field of porous materials) teaches optimizing mechanical properties of porous materials (title, abstract). Firstov teaches that pores are one of the structural elements of a material and porosity can be a result of material technology as well as being regulated consciously, for example, when producing filtered or low-weight materials (pg. 4, paragraph 1). Firstov teaches that improvement of the mechanical properties of porous materials can be achieved via enhancement of fracture toughness by increasing the volume fraction of pores (i.e., pore volume fraction), increasing the relative stiffness of high-porous systems, and increase the absorbing capacity of strain energy at a high porosity (abstract; pg. 11, paragraph 8-9; Fig. 6; pg. 11, pg. 11, paragraph 3-5). Firstov further teaches that when increasing porosity, there is enhancement of fracture toughness of the porous material with an increasing of volume fraction of pores which can be observed at 10-25% of porosity (pg. 17, paragraph 2). Please note that Firstov teaches optimization of porous materials, including increasing volume fraction of pores and that Firstov teaches that enhanced toughness of the porous material can be observed at 10-25% of porosity. As such, one of ordinary skill would have been free to optimize the pore volume fraction in a porous material using standard laboratory techniques available at the time of filing, recognizing that the effectiveness of the porous material would have been affected by pore volume fraction (see MPEP 2144.05 on routine optimization).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite support membrane of Bartels, Porter, Nakano, and Yang by optimizing the pore volume fraction as taught by Firstov with a reasonable expectation of success. As Firstov teaches that porous materials can be optimized to improve its mechanical properties via increasing pore volume fraction, one of ordinary skill would have been motivated to optimize the pore volume fraction with a reasonable expectation of success. One of ordinary skill would have been motivated to optimize the pore volume fraction because Firstov teaches that the volume fraction can be successfully optimized because pores are one of the structural elements of a material as a result of material technology, can be regulated consciously, and can allow for enhancement of fracture toughness of the porous material.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Sixth rejection
Claim 45 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Archer et al ((1985). Metal-Chelate Polymers: Structural/Property Relationships as a Function of the Metal Ion. In: Sheats, J.E., Carraher, C.E., Pittman, C.U. (eds) Metal-Containing Polymeric Systems. Springer, Boston, MA; hereinafter “Archer”; prior art of record).
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach the composite further comprising at least one metal chelated to the polymer matrix.
However, Archer teaches metal-chelate polymers and structural/property relationships as a function of the metal ion (title). Archer teaches that metal ion chelated to preformed polymers can produce marked property changes especially when the metal ion is bonded directly to the polymer backbone (pg. 355, paragraph 1). Archer also teaches that metal-chelate polymers can show superior properties over their organic counterparts in certain applications, although properties such as thermal stability are quite polymer and metal ion dependent (pg. 355, paragraph 1). Archer further teaches the creation of metal chelated polymers using poly(terephthaloyloxalic-bis-amidrazone) (PTO) and poly(terephthaloylbutane-2,3~dihydrazone) (PTBH) and various metal ions including nickel, copper, cadmium, lead, and zinc (see pg. 356; pg. 357, Table 1).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels, Porter, Nakano, and Yang by including metal chelation to the polymer as taught by Archer to arrive at the claimed invention. As Archer teaches metal ion chelation to polymers, one of ordinary skill would have been motivated to make the modification with a reasonable expectation of success. One of ordinary skill would have been motivated to make the modification because Firstov teaches that the known process of chelating metal ions to polymers and that metal-chelate polymers can advantageously show superior properties over their organic counterparts.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary.
Seventh rejection
Claim 62 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Chae et al. (published 13 April 2018). Reinforced PEI/PVdF Multicore-Shell Structure Composite Membranes by Phase Prediction on a Ternary Solution. Polymers 10(4), 436.
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach the functional polymer particles are present in an amount of 20 wt.% to 50 wt.% based on a total mass of the structural polymer and the functional polymer particles.
However, Chae teaches composite membranes made using PEI (i.e., functional polymer) and PVDF (i.e., structural polymer) (see tile, abstract). Chae teaches that many parameters, such as the blend ratio, the molecular weight, and the chi interaction, influence the architecture of a multicore-shell structure, which would determine the membrane’s stability and performance in application (see pg. 2). Chae teaches blending of the two polymers to make the membrane to affect the physical properties of the membrane using three different weight ratios of PVDF:PEI, including ratios of 2:1, 1:1, and 1:2 (see pg. 4). A 1:1 weight ratio of each polymer is 50% of each polymer by weight, and a 2:1 weight ratio is 67% PVDF and 33% PEI. The weight ratios of 33% and 50% of the total combined amount of the polymers lies inside of Applicant’s claimed range of 20-50%. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976) (see MPEP 2144.05).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels, Porter, Nakano, and Yang by using the weight ratios of polymers as disclosed by Chae to arrive at the claimed invention. As Chae teaches creation of PVDF and PEI composite membranes using different weight ratios of PVDF:PEI, including ratios of 2:1, 1:1, and 1:2, one of ordinary skill would have been moticvated to use the same ratios as Chae with a reasonable expectation of success. One of ordinary skill would have been motivated to do so because varying the ratios impacts the diameter of the composite membrane blend, mechanical stability, porosity, and thermal stability (see pg. 8-10).
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary
Eighth rejection
Claim 63 is rejected as being unpatentable over Bartels, Porter, Nakano, and Yang as applied to claim 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 above, and further in view of Bashir et al. (16 Nov 2020). Fundamental Concepts of Hydrogels: Synthesis, Properties, and Their Applications. Polymers 12(11), 2702.
As discussed above, claims 1-3, 6-8, 12, 26, 32, 40-41, 59 and 61 were rendered prima facie obvious by the teachings of Bartels, Porter, Nakano, and Yang.
The difference between the references and the instant claims is that none of the references explicitly teach the functional polymer particles expand to at least twice their dry volume when immersed in a working fluid.
However, Bashir (in a similar field of endeavor of hydrogel polymers) teaches can be synthesized from natural polymers, synthetic polymers, polymerizable synthetic monomers, and a combination of natural and synthetic polymers (see abstract). Bashir teaches synthesized hydrogels have significant properties, such as mechanical strength, biocompatibility, biodegradability, swellability (i.e., expansion), and stimuli sensitivity (see abstract). Bashir also teaches the tendency of water absorption in hydrogels is due to the swelling character, which is monitored by the hydrophilicity of attached groups, swelling media, and crosslinked bonding strength, which helps in maintaining the network structure in the swollen state (see pg. 2). Bashir further teaches “swelling response in different matrix environments, such as water, pH, and ionic strength, is the characteristic of hydrogel to be used in different fields. The hydrogel responds to its biological and environmental media, such as pH, ionic media, solvent, electric field, exposure to light, and temperature. The swelling kinetics and equilibrium are affected by different factors, such as crosslinking ratio, chemical nature of polymers, ionic media, and synthesis state. Swelling is measured in terms of swelling ratio, which is the weight swelling ratio of swollen gel to dry gel. Crosslinking affects the swelling ratio of hydrogel, as highly crosslinked structures have a lower swelling ratio and vice versa. Chemical structure also has a significant function to the swelling property due to the hydrophilic and hydrophobic groups present on the polymer chains. Hydrogels containing more hydrophilic groups swell more as compared to hydrophobic groups. The swelling of hydrogels is also affected by temperature and pH” (see pg. 26).
Bashir does not explicitly teach swelling of the polymer particles at least twice their dry volume. However, as Bashir teaches that swelling of polymers in hydrogels is dependent on parameters such as pH, ionic media, solvent, electric field, exposure to light, temperature, crosslinking ratio (i.e., crosslinking density), and hydrophilic and hydrophobic groups present on the polymer chains, one of ordinary skill would have been motivated to optimize swelling of the polymer particles using standard laboratory techniques available at the time of filing (see MPEP 2144.05).
Therefore, it would have been prima facie obvious to one of ordinary skill at the time of filing to modify the composite of Bartels, Porter, Nakano, and Yang and optimize the swelling ratio of the polymer particles as taught by Bashir to arrive at the claimed invention. As Bashir teaches swelling of polymers in hydrogels is dependent on parameters such as pH, ionic media, solvent, electric field, exposure to light, temperature, crosslinking ratio (i.e., crosslinking density), and hydrophilic and hydrophobic groups present on the polymer chains, one of ordinary skill would have been motivated to optimize swelling/expansion of the polymer particles in hydrogel. One of ordinary skill would have been motivated to do so because hydrogel swelling occurs as a response to its biological and environmental media, such as pH, ionic media, solvent, electric field, exposure to light, temperature, crosslinking ratio, chemical nature of polymers, ionic media, and synthesis state.
Accordingly, the claimed invention was prima facie obvious to one of ordinary skill at the time of filing, especially in the absence of evidence to the contrary
Response to arguments
Applicant's arguments filed 03/26/2026 have been fully considered but they are not persuasive.
On pg. 10-11, Applicant argues that the Office’s characterization of the graphene oxide, crosslinker, and/or additives being chemically bound to one another to form a material matrix draws on elements drawn from different layers of Bartels. Applicant argues Bartels suggests no such configuration of PVDF, PEI, and material matrix layers. Applicant argues that the reference describes multilayer membrane architecture comprising PVDF where PVDF is a support layer of the membrane and not part of the polymer matrix such that Bartels does not disclose the claimed polymer matrix with a semicrystalline structural polymer, Bartels doesn’t describe PEI in a particle configuration, or polymers in form of discrete particles. Applicant argues that PVDF and PEI are separate functional layers such that the reference does not teach the structure as instantly claimed in the configuration claimed.
In response, the examiner disagrees. First, Bartels, while teaching discrete layers, explicitly teaches that the materials within the membrane may be “chemically bound to any combination of each other to result in a material matrix” (see above), and does not exclude or disavow the use of any other configurations. Second, the cited Porter reference provides the explicit teachings regarding freeze-casting, particles dispersion throughout the freezing vehicle for the creation of the scaffold (a requirement of the instant claims), which are advantageously simple, inexpensive, and adaptable technique to fabricate porous scaffolds and composites, allows for impregnation and infiltration of polymers into the porous scaffolds (a requirement of the instant claims), and strong covalent bonding between phases of ceramic and polymer scaffolds to protect against interfacial shear and delamination (see Porter reference). Indeed, an obviousness rejection under 35 U.S.C 103 requires one of ordinary skill to balance each individual teaching of the prior art references with the totality of the references in combination. When looking at Bartels individually, one of ordinary skill is given general teachings regarding the creation of porous membranes using polymers, but one of ordinary skill is not limited to just the teachings of Bartels because the prior art recognizes a known configuration of polymers within a macroporous scaffold, meeting the limitation as instantly claimed.
On pg. 12-14, Applicant argues the proposed modification would destroy the layered membrane architecture of Bartels. Specifically, Applicant argues that the reference is directed to membranes for water purification and desalination for rapid water transport and high-water flux (citing to para 0028 of Bartels), that having high water flux is desirable and modifications to the graphene oxide membrane are intended to increase permeability of the membrane (citing to para 0067) for rapid water transport between interlayer spaces. Applicant argues that incorporating the materials of Bartels into the through pores of a freeze-cast scaffold such as those described in Porter and Nakano, fundamentally alter the architecture of Bartels, disrupt the layers and eliminate the reference’s stated objective of fast, high flux water transport. Applicant argues that introducing the polymers into the pores would impede water transport through the membrane such that there is no motivation to make the proposed modification.
In response, the examiner disagrees. First, Applicant’s argument regarding, e.g., disruption of the layers and eliminating the objective of fast water flux must be substantiated by empirical evidence. Arguments presented by applicant cannot take the place of evidence in the record. See In re De Blauwe, 736 F.2d 699, 705, 222 USPQ 191, 196 (Fed. Cir. 1984); In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965); In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997) ("An assertion of what seems to follow from common experience is just attorney argument and not the kind of factual evidence that is required to rebut a prima facie case of obviousness."). See MPEP § 716.01(c) for examples of applicant statements which are not evidence and which must be supported by an appropriate affidavit or declaration. Applicant fails to point to anywhere in Bartels that the multilayer configuration cannot be modified in any way to achieve similar/same results. The reference itself explicitly discloses that materials within the membrane may be “chemically bound to any combination of each other to result in a material matrix” and “any combination of the above-described elements in all possible variations thereof is contemplated unless otherwise indicated herein or otherwise clearly contradicted by context.” (see, e.g., para 0159). Put simply, while Bartels uses a multilayer configuration to achieve that result, there is no explicit disavowal of any other configurations of the arrangement of the materials within the scaffold.
Second, for the purposes of rebutting Applicant’s argument, the examiner points Applicant to Gaudillere et al (Freeze-casting: Fabrication of highly porous and hierarchical ceramic supports for energy applications; Boletín de la Sociedad Española de Cerámica y Vidrio; Volume 55, Issue 2, March–April 2016, Pages 45-54), which specifically discusses that freeze cast porous scaffolds (including polymers like PVA, PVB, PEG) containing materials impregnated into the scaffold pores (see, e.g., Fig. 7), and suggests their potential capability to be used for water desalination techniques (see, e.g., pg. 52 col 1-2; see also Fig. 7 where the pore in the freeze-cast scaffold contains carbon nanotubes deposited into the pores). Thus the prior art recognized, at least as early as 2016 (approx. 4 years before Applicant’s priority date) that freeze cast scaffolds with pores infiltrated with materials advantageously “present all the characteristics for boosting gas transport and to substitute randomly organized porous support which hinder to reach industrial targets. Few reports of existing freeze-cast energy applications are available in literature but the first published results have shown the feasibility of incorporate freeze-cast porous structures as SOFC and MIEC membrane component. Water desalination has also been pointed out as a possible application even if the complete lack of literature data does not allow to rule about it” (see pg. 53, col 1).
On pg. 14-15, Applicant argues that Yang describes polymeric hydrogels which are materials designed to absorb and retain large quantities of water within a crosslinked polymer network, while Bartels is used for rapid water flux, etc., such that incorporating hydrogels into the membrane of Bartels would be expected to retain water within the membrane rather than rapid transport through it. Applicant urges that the Office has not articulated a sufficient reason why a PHOSITA would modify Bartels with hydrogel particles. Applicant then argues the dependent claims are non-obvious for much of the same reasons.
In response, the examiner disagrees. Yang does articulate a teaching, suggestion, and motivation for using hydrogels in a porous composite membrane. For example, Yang teaches several advantageous features of hydrogels. For example, while Yang discloses that the hydrogels can absorb water and swell, “the combination of a rigid porous membrane with a soft functional hydrogel by a suited preparation technique enables that the functionality of the hydrogel can be applied in a unique way. The most important preparation strategies for hydrogel composite membranes, i.e., pore-filling, various surface-grafting methods and combinations thereof, will be discussed. The structural diversity of the hydrogels is based on the use of a wide range of synthetic monomers, but biopolymers or their derivatives can also be applied. The interplay of the membrane pore structure, the structure of the hydrogel and the distribution of the hydrogel in the pore space can lead to different types of composite membranes with completely different potential applications.” (see abstract). Yang also explicitly teaches several advantageous features of hydrogels within composite membranes, including selective ad(b)sorption, anti-fouling, pore-filling/-narrowing, stimuli-response and serving as biocompatible/-active layer (pg. 2790, col 1, paragraph 1; pg. 2794; col 1, paragraph 2). As such, the rejections are maintained for the reasons set forth above.
Conclusion
NO CLAIMS ALLOWED.
THIS ACTION IS MADE FINAL. 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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/G.C.R./Examiner, Art Unit 1651
/THOMAS J. VISONE/Supervisory Patent Examiner, Art Unit 1672
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