| 1. |
- Alexakis, Alexandros Efraim, et al.
(författare)
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Modification of cellulose through physisorption of cationic bio-based nanolatexes - comparing emulsion polymerization and RAFT-mediated polymerization-induced self-assembly
- 2021
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Ingår i: Green Chemistry. - : Royal Society of Chemistry (RSC). - 1463-9262 .- 1463-9270. ; 23:5, s. 2113-2122
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Tidskriftsartikel (refereegranskat)abstract
- The polymerization of a bio-based terpene-derived monomer, sobrerol methacrylate (SobMA), was evaluated in the design of polymeric nanoparticles (nanolatexes). Their synthesis was accomplished by using emulsion polymerization, either by free-radical polymerization in the presence of a cationic surfactant or a cationic macroRAFT agent by employing RAFT-mediated polymerization-induced self-assembly (PISA). By tuning the length of the hydrophobic polymer, it was possible to control the nanoparticle size between 70 and 110 nm. The average size of the latexes in both wet and dry state were investigated by microscopy imaging and dynamic light scattering (DLS). Additionally, SobMA was successfully copolymerized with butyl methacrylate (BMA) targeting soft-core nanolatexes. The comparison of the kinetic profile of the cationically stabilized nanolatexes highlighted the differences of both processes. The SobMA-based nanolatexes yielded high T-g similar to 120 degrees C, while the copolymer sample exhibited a lower T-g similar to 50 degrees C, as assessed by Differential Scanning Calorimetry (DSC). Thereafter, the nanolatexes were adsorbed onto cellulose (filter paper), where they were annealed at elevated temperatures to result in polymeric coatings. Their morphologies were analysed by Field Emission Scanning Electron Microscopy (FE-SEM) and compared to a commercial sulfate polystyrene latex (PS latex). By microscopic investigation the film formation mechanism could be unravelled. Water contact angle (CA) measurements verified the transition from a hydrophilic to a hydrophobic surface after film formation had occured. The obtained results are promising for the toolbox of bio-based building blocks, focused on sobrerol-based monomers, to be used in emulsion polymerizations either for tailored PISA-latexes or facile conventional latex formation, in order to replace methyl methacrylate or other high T-g-monomers.
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| 2. |
- Biundo, Antonino, et al.
(författare)
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Regio- and stereoselective biocatalytic hydration of fatty acids from waste cooking oils en route to hydroxy fatty acids and bio-based polyesters
- 2023
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Ingår i: Enzyme and microbial technology. - : Elsevier BV. - 0141-0229 .- 1879-0909. ; 163
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Tidskriftsartikel (refereegranskat)abstract
- The development of biorefinery approaches is of great relevance for the sustainable production of valuable compounds. In accordance with circular economy principles, waste cooking oils (WCOs) are renewable resources and biorefinery feedstocks, which contribute to a reduced impact on the environment. Frequently, this waste is wrongly disposed of into municipal sewage systems, thereby creating problems for the environment and increasing treatment costs in wastewater treatment plants. In this study, regenerated WCOs, which were intended for the production of biofuels, were transformed through a chemo-enzymatic approach to produce hydroxy fatty acids, which were further used in polycondensation reaction for polyester production. Escherichia coli whole cell biocatalyst containing the recombinantly produced Elizabethkingia meningoseptica Oleate hydratase (Em_OhyA) was used for the biocatalytic hydration of crude WCOs-derived unsaturated free fatty acids for the production of hydroxy fatty acids. Further hydrogenation reaction and methylation of the crude mixture allowed the pro-duction of (R)-10-hydroxystearic acid methyl ester that was further purified with a high purity (> 90%), at gram scale. The purified (R)-10-hydroxystearic acid methyl ester was polymerized through a polycondensation reaction to produce the corresponding polyester. This work highlights the potential of waste products to obtain bio-based hydroxy fatty acids and polyesters through a biorefinery approach.
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| 3. |
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| 4. |
- Farhat, Wissam, et al.
(författare)
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Biocatalysis for terpene-based polymers
- 2019
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Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences. - : WALTER DE GRUYTER GMBH. - 0939-5075 .- 1865-7125. ; 74:3-4, s. 90-99
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Tidskriftsartikel (refereegranskat)abstract
- Accelerated generation of bio-based materials is vital to replace current synthetic polymers obtained from petroleum with more sustainable options. However, many building blocks available from renewable resources mainly contain unreactive carbon-carbon bonds, which obstructs their efficient polymerization. Herein, we highlight the potential of applying biocatalysis to afford tailored functionalization of the inert carbocyclic core of multicyclic terpenes toward advanced materials. As a showcase, we unlock the inherent monomer reactivity of norcamphor, a bicyclic ketone used as a monoterpene model system in this study, to afford polyesters with unprecedented backbones. The efficiencies of the chemical and enzymatic Baeyer-Villiger transformation in generating key lactone intermediates are compared. The concepts discussed herein are widely applicable for the valorization of terpenes and other cyclic building blocks using chemoenzymatic strategies.
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| 5. |
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| 6. |
- Farhat, Wissam, et al.
(författare)
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Lactone monomers obtained by enzyme catalysis and their use in reversible thermoresponsive networks
- 2020
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Ingår i: Journal of Applied Polymer Science. - : John Wiley and Sons Inc.. - 0021-8995 .- 1097-4628. ; 137:18
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Tidskriftsartikel (refereegranskat)abstract
- Enzyme-catalyzed transformations have a great potential in both the pharmaceutical and chemical industry to achieve complex and (stereo)selective synthesis under mild reaction conditions. Still, the implementation of biocatalysis in the prerequisite upgrading of inert synthons into activated monomers for polymer applications has not yet been fully realized. In this contribution, we show that scaled-up synthesis of bicyclic norcamphor lactone using an engineered Baeyer–Villiger monooxygenase (BVMO) is feasible to reach complete conversion of the corresponding ketone in 24 h in shake-flask. The lactone monomer obtained by enzyme catalysis was copolymerized with ε-caprolactone via ring-opening polymerization to study the impact of the additional ring on material properties. Moreover, four-arm star-like, homo and block copolymers were designed from ε-caprolactone, ε-decalactone, and norcamphor lactone and characterized for their structural and thermal properties. These newly explored macromolecules were functionalized with furan rings using the enzyme Candida antarctica lipase B which allowed the formation of thermolabile networks via the pericyclic reaction with bismaleimide by means of Diels–Alder chemistry. The bonding/debonding state of these star-like based materials can be tuned by a suitable selection of thermal treatment. The temperature-dependent reversibility was assessed by thermal analysis and solubility test. Our results presented here shed light on the high potential of the use of chemoenzymatic approaches in the synthesis of new functional materials with tuned physiochemical properties.
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| 7. |
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| 8. |
- Lopez-Lorenzo, Ximena, et al.
(författare)
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Whole-cell Mediated Carboxylation of 2-Furoic Acid Towards the Production of Renewable Platform Chemicals and Biomaterials
- 2023
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Ingår i: ChemCatChem. - : Wiley. - 1867-3880 .- 1867-3899. ; 15:6
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Tidskriftsartikel (refereegranskat)abstract
- 2,5-furandicarboxylic acid (FDCA) has gained great industrial interest as a renewable alternative to terephthalic acid (TPA) in the generation of bioplastics. However, chemical production of FDCA involves harsh reaction conditions not aligned with sustainable manufacturing. Herein, we demonstrate the use of whole-cell mediated synthesis of FDCA from 2-furoic acid (FA) as substrate. Our approach moves away from the use of isolated enzymes by supplementing the UbiD−UbiX system in E. coli with the gene of P. thermopropionicum HmfF (PtHmfF) known to generate FDCA. The resulting whole-cell system allows for production of FDCA under mild conditions by carboxylation of FA. We show how the enzymatically produced FDCA can be used to generate FDCA-based biopolymers along with a terpene-based diol monomer by enzymatic polycondensation catalyzed by Candida antarctica lipase B (CALB). This work high-lights how underutilized hemicellulose-derived C5 building blocks can be converted into renewable platform chemicals and materials by a simple cell factory in a CO2 sequestration process.
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| 9. |
- Malmström, Eva, Professor, 1966-, et al.
(författare)
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Sustainable terpene-based polymeric materials
- 2019
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Ingår i: Abstracts of Papers of the American Chemical Society. - : American Chemical Society (ACS). - 0065-7727. ; 257
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 10. |
- Stamm, Arne, et al.
(författare)
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A retrobiosynthesis-based route to generate pinene-derived polyesters
- 2019
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Ingår i: ChemBioChem. - : Wiley. - 1439-4227 .- 1439-7633. ; 20, s. 1664-1671
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Tidskriftsartikel (refereegranskat)abstract
- Significantly increased production of biobased polymers is aprerequisite to replace petroleum-based materials towardsreaching a circular bioeconomy. However, many renewablebuilding blocks from wood and other plant material are notdirectly amenable for polymerization, due to their inert backbonesand/or lack of functional group compatibility with thedesired polymerization type. Based on a retro-biosyntheticanalysis of polyesters, a chemoenzymatic route from (@)-apinenetowards a verbanone-based lactone, which is furtherused in ring-opening polymerization, is presented. Generatedpinene-derived polyesters showed elevated degradation andglass transition temperatures, compared with poly(e-decalactone),which lacks a ring structure in its backbone. Semirationalenzyme engineering of the cyclohexanone monooxygenasefrom Acinetobacter calcoaceticus enabled the biosynthesis ofthe key lactone intermediate for the targeted polyester. As aproof of principle, one enzyme variant identified from screeningin a microtiter plate was used in biocatalytic upscaling,which afforded the bicyclic lactone in 39% conversion in shakeflask scale reactions.
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| 11. |
- Stamm, Arne, et al.
(författare)
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Chemo- enzymatic pathways toward pinene- based renewable materials
- 2019
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Ingår i: Green Chemistry. - : Royal Society of Chemistry (RSC). - 1463-9262 .- 1463-9270. ; 21:10, s. 2720-2731
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Tidskriftsartikel (refereegranskat)abstract
- Sobrerol methacrylate (SobMA) was synthesized and subsequently polymerized using different chemical and enzymatic routes. Sobrerol was enzymatically converted from -pinene in a small model scale by a Cytochrome P450 mutant from Bacillus megaterium. Conversion of sobrerol into SobMA was performed using both classical ester synthesis, i.e., acid chloride-reactions in organic solvents, and a more green approach, the benign lipase catalysis. Sobrerol was successfully esterified, leaving the tertiary alcohol and ene to be used for further chemistry. SobMA was polymerized into PSobMA using different radical polymerization techniques, including free radical (FR), controlled procedures (Reversible Addition Fragmentation chain-Transfer polymerization, (RAFT) and Atom Transfer Radical Polymerization (ATRP)) as well as by enzyme catalysis (horseradish peroxidase-mediated free radical polymerization). The resulting polymers showed high glass-transition temperatures (T-g) around 150 degrees C, and a thermal degradation onset above 200 degrees C. It was demonstrated that the T-g could be tailored by copolymerizing SobMa with appropriate methacrylate monomers and that the Flory-Fox equation could be used to predict the T-g. The versatility of PSobMA was further demonstrated by forming crosslinked thin films, either using the ene'-functionality for photochemically initiated thiol-ene'-chemistry, or reacting the tertiary hydroxyl-group with hexamethoxymethylmelamine, as readily used for thermally curing coatings systems.
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| 12. |
- Stamm, Arne, 1991-
(författare)
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Exploring the Use of Terpenes as Renewable Polymer Feedstock
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Rising environmental awareness and responsibility has increased the demand for novel, bio-based sustainable materials. Therefore, there is an extensive need to research and develop closed-loop materials from novel feedstocks that can be generated using benign, environmentally friendly synthetic routes. The work presented in this thesis was focused on the development of polymeric materials from biomass waste-feedstocks. Especially the use of turpentine, a classical underutilized side-stream of the forest industry, and its main component α-pinene was the key objective of this work. To showcase the inherent potential of terpenes as a source material for novel biopolymers, α-pinene was transformed into different monomers and subsequently polymerized. The synthesis and polymerization of the pinene derived sobreryl methacrylate (SobMA) was studied using different radical polymerization techniques, including free radical polymerizations and controlled procedures. Post-modifications were further demonstrated by synthesizing crosslinked thin films, utilizing the tertiary alcohol and the unsaturation present in each monomer unit. The same methacrylic monomer was further utilized for the polymerization of amphiphilic block copolymers to form cationic polymer latexes. Pinene derived polyesters were further developed via two different pathways. In the first pathway, α-pinene was oxidized into the bicyclic verbanone based lactone (VaL) and subsequently polymerized resulting in a biobased semicrystalline polyester. In the second pathway, polyesters were synthesized via polycondensation, utilizing the diol (1-(1'-hydroxyethyl)-3-(2'-hydroxyethyl)-2,2-dimethylcyclobutane (HHDC)) obtained from the oxidative cleavage of the double bond of α-pinene together with unsaturated biobased diacids. The resulting terpene based unsaturated polyester resins were afterwards crosslinked via UV-irradiation to yield polyester networks with adjustable properties. The use of enzymatic catalysis in key synthetic steps was elaborated to showcase the potential of replacing harsh chemical conditions with mild reaction conditions in aqueous environment.
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| 13. |
- Stamm, Arne, et al.
(författare)
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Pinene-Based Oxidative Synthetic Toolbox for Scalable Polyester Synthesis
- 2021
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Ingår i: JACS Au. - : American Chemical Society (ACS). - 2691-3704. ; 1:11, s. 1949-1960
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Tidskriftsartikel (refereegranskat)abstract
- Generation of renewable polymers is a long-standing goal toward reaching a more sustainable society, but building blocks in biomass can be incompatible with desired polymerization type, hampering the full implementation potential of biomaterials. Herein, we show how conceptually simple oxidative transformations can be used to unlock the inherent reactivity of terpene synthons in generating polyesters by two different mechanisms starting from the same alpha-pinene substrate. In the first pathway, alpha-pinene was oxidized into the bicyclic verbanone-based lactone and subsequently polymerized into star-shaped polymers via ring-opening polymerization, resulting in a biobased semicrystalline polyester with tunable glass transition and melting temperatures. In a second pathway, polyesters were synthesized via polycondensation, utilizing the diol 1-(1'-chydroxyethyl)-3-(2'-hydroxyethyl)-2,2-dimethylcyclobutane (HHDC) synthesized by oxidative cleavage of the double bond of alpha-pinene, together with unsaturated biobased diesters such as dimethyl maleate (DMM) and dimethyl itaconate (DMI). The resulting families of terpenebased polyesters were thereafter successfully cross-Iinked by either transetherification, utilizing the terminal hydroxyl groups of the synthesized verbanone-based materials, or by UV irradiation, utilizing the unsaturation provided by the DMM or DMI moieties within the HHDC-based copolymers. This work highlights the potential to apply an oxidative toolbox to valorize inert terpene metabolites enabling generation of biosourced polyesters and coatings thereof by complementary mechanisms.
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| 14. |
- Stamm, Arne, et al.
(författare)
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Pinene-based oxidative synthetic toolbox for scalable polyester synthesis
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Pinene derived polyesters were synthesized utilizing two different synthons obtained from α-pinene. In the first pathway, α-pinene was oxidized into the bicyclic verbanone based lactone (VaL) and subsequently polymerized into star-shaped polymers, resulting in biobased semicrystalline polyester with tunable glass transition and melting temperatures. In the second pathway, polyesters were synthesized via polycondensation, utilizing the diol synthesized by oxidative cleavage of the double bond of α-pinene (1-(1'-hydroxyethyl)-3-(2'-hydroxyethyl)-2,2-dimethylcyclobutane (HHDC)) together with unsaturated biobased diesters such as dimethyl maleate (DMM) and dimethyl itaconate (DMI), respectively. The resulting terpene-based polyesters were thereafter successfully crosslinked by either transetherification, utilizing the terminal hydroxyl groups of the synthesized verbanone-based materials, or by UV-irradiation, utilizing the unsaturation provided by the DMM or DMI moieties within the HHDC-based polymers.
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| 15. |
- Stamm, Arne, et al.
(författare)
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The triolein/aqueous interface and lipase activity studied by spectroscopic ellipsometry and coarse grained simulations
- 2018
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Ingår i: Chemistry and Physics of Lipids. - : Elsevier BV. - 0009-3084 .- 1873-2941. ; 211, s. 37-43
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Tidskriftsartikel (refereegranskat)abstract
- In spite of the importance of the triglyceride aqueous interface for processes like emulsification, surfactant interactions and lipase activity, relatively little is known about this interface compared to that between alkanes and water. Here, the contact between triolein and water was investigated in terms of water inclusion in the oil phase and orientation of the molecules at the interface. Coarse grained models of triglycerides in contact with water were constructed and correlated with experimental results of the changes in thickness and refractive index, obtained using spectroscopic ellipsometry of spin-coated triolein films. The topography of the layer was revealed by atomic force microscopy. Dry triolein and a triolein sample after equilibration with water were also compared structurally using small-angle X-ray scattering. Additionally, the kinetics of adsorption/activity of three different variants of the Thermomyces lanuginosus lipase (TLL) were investigated. The results show that uptake of water in the triolein phase leads to increase in thickness of the layer. The observed increase of thickness was further enhanced by an active lipase but reduced when an inactive mutant of the enzyme was applied.
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| 16. |
- Zokaei, Sepideh, 1991, et al.
(författare)
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Toughening of a Soft Polar Polythiophene through Copolymerization with Hard Urethane Segments
- 2021
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Ingår i: Advanced Science. - : Wiley. - 2198-3844. ; 8:2
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Tidskriftsartikel (refereegranskat)abstract
- Polar polythiophenes with oligoethylene glycol side chains are exceedingly soft materials. A low glass transition temperature and low degree of crystallinity prevents their use as a bulk material. The synthesis of a copolymer comprising 1) soft polythiophene blocks with tetraethylene glycol side chains, and 2) hard urethane segments is reported. The molecular design is contrary to that of other semiconductor-insulator copolymers, which typically combine a soft nonconjugated spacer with hard conjugated segments. Copolymerization of polar polythiophenes and urethane segments results in a ductile material that can be used as a free-standing solid. The copolymer displays a storage modulus of 25 MPa at room temperature, elongation at break of 95%, and a reduced degree of swelling due to hydrogen bonding. Both chemical doping and electrochemical oxidation reveal that the introduction of urethane segments does not unduly reduce the hole charge-carrier mobility and ability to take up charge. Further, stable operation is observed when the copolymer is used as the active layer of organic electrochemical transistors.
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