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As awareness of the environmental impact of fossil-based polymers grows, the demand for biobased alternatives rises. In this context, combining eco-friendly synthesis techniques with renewable resources is important to produce polymers efficiently and sustainably. Furandicarboxylic acid (FDCA) is one of the key building blocks for producing biobased polymers. However, most studies predominantly focus on 2,5-FDCA, while FDCA encompasses other noteworthy isomers, namely, 2,4- and 3,4-FDCA. The polymers derived from these two isomers have recently gained attention due to their promising properties. In this study, an environmentally friendly approach for producing biobased polyesters from 2,5-, 2,4-, and 3,4-FDCA dimethyl ester isomers is proposed. The synthesis is conducted under greener conditions, utilizing Candida antarctica lipase B (CALB) enzyme as a biocatalyst. The performance of the enzyme is assessed, revealing CALB preference for polymerizing 2,5-FDCA over 2,4- and 3,4-FDCA dimethyl ester, which is elucidated by docking analysis. Moreover, CALB shows varying rates of cyclic oligomer formation for each isomer, favoring 2,5-FDCA cyclization. The structure-property relationship, encompassing the variation in isomeric structure, is evaluated through structural characterization, thermal analysis, and surface properties. This study primarily emphasized enzymatic polymerization and highlighted its versatility in accommodating different monomer isomeric substitutions.

This review sheds light on urgent questions that arise from the need to replace a polymer resin,-poly(ethylene terephthalate), which represents 7.7% market-share in the global plastic demand (Plastics-the Facts 2019), by renewable alternatives. The main question that this review will address is: what are the most promising PET replacements made from biomass? Currently, under debate is naturally its biobased counterpart bio-PET (or even recycle rPET), as well as other aromatic key-players with comparable thermo-mechanical performance and enhanced barrier properties, such as poly(ethylene 2,5-furandicarboxylate) (PEF) and poly(trimethylene 2,5-furandicarboxylate) (PTF). They are most adequate for packaging, but not restricted to. Additional alternatives are the miscellaneous of lignin-based thermoplastic polymers, although the technology involved in this latter case is still premature. (Bio)degradable aliphatic polyesters, despite their typical inferior thermo-mechanical properties, can also play a role e.g., among PET fiber industry applications. Poly(lactic acid) (PLA) is the most developed renewable polyester, already a commercial reality. All biobased polymers reviewed face a major hindrance for their wider deployment their cost-competitiveness. A pertinent question arises then: Are these alternatives, or will they be, economically feasible? Social, political and legal frameworks together with supportive financial schemes are boosting rapid changes. In the future, most probably more than one polymer will come to the market and will be used in some of the panoply of PET applications. This evaluation overviews sustainability issues, including perspectives on their green synthesis. Moreover, this review does also not neglect the accumulation of plastics waste in the environment and the inherent challenges of polymers' end-of-life. Approximately 8 M tons of polymers waste leaks into the environment each year, a fact not disconnected to PET's non-biodegradability and s

The attention towards the utilization of sustainable feedstocks for polymer synthesis has grown exponentially in recent years. One of the spotlighted monomers derived from renewable resources is 2,5-furandicarboxylic acid (FDCA), one of the most promising bio-based monomers, due to its resemblance to petroleum-based terephthalic acid. Very interesting synthetic routes using this monomer have been reported in the last two decades. Combining the use of bio-based monomers and non-toxic chemicals via enzymatic polymerizations can lead to a robust and favorable approach towards a greener technology of bio-based polymer production. In this chapter, a brief introduction to FDCA-based monomers and enzymatic polymerizations is given, particularly focusing on furan-based polymers and their polymerization. In addition, an outline of the recent developments in the field of enzymatic polymerizations is discussed.

The attention towards the utilization of sustainable feedstocks for polymer synthesis has grown exponentially in recent years. One of the spotlighted monomers derived from renewable resources is 2,5-furandicarboxylic acid (FDCA), one of the most promising bio-based monomers, due to its resemblance to petroleum-based terephthalic acid. Very interesting synthetic routes using this monomer have been reported in the last two decades. Combining the use of bio-based monomers and non-toxic chemicals via enzymatic polymerizations can lead to a robust and favorable approach towards a greener technology of bio-based polymer production. In this chapter, a brief introduction to FDCA-based monomers and enzymatic polymerizations is given, particularly focusing on furan-based polymers and their polymerization. In addition, an outline of the recent developments in the field of enzymatic polymerizations is discussed.

This review sheds light on urgent questions that arise from the need to replace a polymer resin,-poly(ethylene terephthalate), which represents 7.7% market-share in the global plastic demand (Plastics-the Facts 2019), by renewable alternatives. The main question that this review will address is: what are the most promising PET replacements made from biomass? Currently, under debate is naturally its biobased counterpart bio-PET (or even recycle rPET), as well as other aromatic key-players with comparable thermo-mechanical performance and enhanced barrier properties, such as poly(ethylene 2,5-furandicarboxylate) (PEF) and poly(trimethylene 2,5-furandicarboxylate) (PTF). They are most adequate for packaging, but not restricted to. Additional alternatives are the miscellaneous of lignin-based thermoplastic polymers, although the technology involved in this latter case is still premature. (Bio)degradable aliphatic polyesters, despite their typical inferior thermo-mechanical properties, can also play a role e.g., among PET fiber industry applications. Poly(lactic acid) (PLA) is the most developed renewable polyester, already a commercial reality. All biobased polymers reviewed face a major hindrance for their wider deployment their cost-competitiveness. A pertinent question arises then: Are these alternatives, or will they be, economically feasible? Social, political and legal frameworks together with supportive financial schemes are boosting rapid changes. In the future, most probably more than one polymer will come to the market and will be used in some of the panoply of PET applications. This evaluation overviews sustainability issues, including perspectives on their green synthesis. Moreover, this review does also not neglect the accumulation of plastics waste in the environment and the inherent challenges of polymers' end-of-life. Approximately 8 M tons of polymers waste leaks into the environment each year, a fact not disconnected to PET's non-biodegradability and s

This review sheds light on urgent questions that arise from the need to replace a polymer resin,-poly(ethylene terephthalate), which represents 7.7% market-share in the global plastic demand (Plastics-the Facts 2019), by renewable alternatives. The main question that this review will address is: what are the most promising PET replacements made from biomass? Currently, under debate is naturally its biobased counterpart bio-PET (or even recycle rPET), as well as other aromatic key-players with comparable thermo-mechanical performance and enhanced barrier properties, such as poly(ethylene 2,5-furandicarboxylate) (PEF) and poly(trimethylene 2,5-furandicarboxylate) (PTF). They are most adequate for packaging, but not restricted to. Additional alternatives are the miscellaneous of lignin-based thermoplastic polymers, although the technology involved in this latter case is still premature. (Bio)degradable aliphatic polyesters, despite their typical inferior thermo-mechanical properties, can also play a role e.g., among PET fiber industry applications. Poly(lactic acid) (PLA) is the most developed renewable polyester, already a commercial reality. All biobased polymers reviewed face a major hindrance for their wider deployment their cost-competitiveness. A pertinent question arises then: Are these alternatives, or will they be, economically feasible? Social, political and legal frameworks together with supportive financial schemes are boosting rapid changes. In the future, most probably more than one polymer will come to the market and will be used in some of the panoply of PET applications. This evaluation overviews sustainability issues, including perspectives on their green synthesis. Moreover, this review does also not neglect the accumulation of plastics waste in the environment and the inherent challenges of polymers' end-of-life. Approximately 8 M tons of polymers waste leaks into the environment each year, a fact not disconnected to PET's non-biodegradability and s

A series of poly(tetrahydrofuran)s with molecular weights above entanglement molecular weight Me were synthesized, and one of their end-groups was functionalized with a supramolecular entity so that the corresponding polymers form a brushlike structure suitable for comparison with conventional irreversible bottlebrush polymers. To compare their relaxation mechanisms, linear rheology was employed and showed that a hierarchical relaxation, which is usually observed in bottlebrush polymers, occurs in these materials, too. The polymer chain segments close to the supramolecular backbone are highly immobilized due to strong association in the center of polymer brush and cannot relax via reptation mechanism, which is mainly responsible for linear entangled polymer relaxations. Therefore, disentanglement can take much longer through contour length fluctuations and arm retraction processes similar to covalent bottlebrush polymers and combs. The relaxed ends of polymers then act as solvent to let the remaining segments of the polymeric brush undergo Rouse-like motions (constraint release Rouse). At longer times, additional plateau appears, which can be attributed to the relaxation of the entire supramolecular bottlebrush polymer via hopping or reptative motions. With an increase of temperature, viscoelastic solid behavior turns into viscoelastic liquid due to reversible depolymerization of the supramolecular backbone of the bottlebrush polymer. The elastic modulus (G′ in the order of kPa) was much less than the values found for the entanglement plateau modulus of linear poly(tetrahydrofuran) (in order of MPa). This low modulus value, which exists up to very low frequencies (high temperatures), makes them a good candidate for supersoft elastomers.

Previously, we have synthesized a diverse range of 2,5-furandicarboxylic acid (FDCA)-based semiaromatic polyamides via enzymatic polymerization. This novel class of polymers are biobased alternatives to polyphthalamides, which are petrol-based semiaromatic polyamides. From a commercial perspective, they have interesting properties as high-performance materials and engineering thermoplastics. It is even more appealing to explore novel FDCA-based polyamides with added functionality, for the development of sustainable functional materials. Here, a set of FDCA-based heteroatom polyamides have been successfully produced via Novozyme 435 (N435)-catalyzed polymerization of biobased dimethyl 2,5-furandicarboxylate with (potentially)heteroatom diamines, namely, 4,9-dioxa-1,12-dodecanediamine (DODA), diethylenetriamine, and 3,3-ethylenediiminopropylamine. We performed the enzymatic polymerization in solution and bulk. The latter approach is more sustainable and results in higher molecular weight products. Among the tested heteroatom diamines, N435 shows the highest catalytic activity toward DODA. Furthermore, we find that all obtained FDCA-based heteroatom polyamides are amorphous materials with a relatively high thermal stability. These heteroatom polyamides display a glass-transition temperature ranging from 41 to 107 °C.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) (P4VPE) with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and X-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e., the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (sample 3, Q(eq) = 89 mg g(-1)) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (sample 1, Q(eq) = 5.1 mg g(-1)). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

The glycolytic recycling of waste PET presents a challenge for the production of secondary value-added products, such as alkyd resins. A way to overcome the unsatisfactory mechanical, drying and chemical resistance properties of alkyds obtained from difunctional glycolyzates was proposed. Waste PET was glycolyzed using multifunctional alcohols: glycerol (G), trimethylolethane (TME), trimethylolpropane (TMP) and pentaerythritol (PE), giving tetra-and hexa-functional glycolyzates and, for comparison, using diethylene glycol (DEG), propylene glycol (PG) and dipropylene glycol (DPG) giving di-functional glycolyzates. The obtained glycolyzates were examined by H-1 and C-13 NMR, FTIR spectroscopy and elemental analysis and further used in the synthesis of alkyd resins. The properties of the prepared alkyd resins (acid, hydroxyl and iodine values, color, average molar masses and molar mass distributions, viscosity, drying time, hardness, flexibility, gloss, adhesion and chemical resistance) were investigated with respect to the functionality and the structure of the used glycolyzates. Alkyd resins derived from multifunctional glycolyzates (TME and TMP) showed considerably enhanced properties compared to those produced from difunctional glycolyzates and also to conventional general purpose resins.

Biotechnologically accessible 1,4-butanediol and vegetal oil-based diethyl sebacate were copolymerized with bicyclic acetalized d-glucose derivatives (Glux) by polycondensation both in the melt at high temperature and in solution at mild temperature mediated by polymer-supported Candida antarctica lipase B (CALB). Two series of random copolyesters (PBxGluxySeb and PBSebxGluxy) were prepared differing in which d-glucose derivative (Glux diol or Glux diester) was used as comonomer. The three parent homopolyesters PBSeb, PBGlux, and PGluxSeb were prepared as well. Both methods were found to be effective for polymerization although significant higher molecular weights were achieved by melt polycondensation. The thermal properties displayed by the copolyesters were largely dependent on composition and also on the functionality of the replacing Glux unit. The thermal stability of PBSeb was retained or even slightly increased after copolymerization with Glux, whereas crystallinity and melting temperature were largely depressed. On the contrary, the glass-transition temperature noticeably increased with the content in Glux units. PGluxSeb distinguished in displaying both Tg and Tm higher than PBSeb because a different crystal structure is adopted by this homopolyester. The hydrolytic degradability of PBSeb in water was enhanced by copolymerization, in particular, when biodegradation was assisted by lipases., Peer Reviewed, Postprint (author’s final draft)

The glycolytic recycling of waste PET presents a challenge for the production of secondary value-added products, such as alkyd resins. A way to overcome the unsatisfactory mechanical, drying and chemical resistance properties of alkyds obtained from difunctional glycolyzates was proposed. Waste PET was glycolyzed using multifunctional alcohols: glycerol (G), trimethylolethane (TME), trimethylolpropane (TMP) and pentaerythritol (PE), giving tetra-and hexa-functional glycolyzates and, for comparison, using diethylene glycol (DEG), propylene glycol (PG) and dipropylene glycol (DPG) giving di-functional glycolyzates. The obtained glycolyzates were examined by H-1 and C-13 NMR, FTIR spectroscopy and elemental analysis and further used in the synthesis of alkyd resins. The properties of the prepared alkyd resins (acid, hydroxyl and iodine values, color, average molar masses and molar mass distributions, viscosity, drying time, hardness, flexibility, gloss, adhesion and chemical resistance) were investigated with respect to the functionality and the structure of the used glycolyzates. Alkyd resins derived from multifunctional glycolyzates (TME and TMP) showed considerably enhanced properties compared to those produced from difunctional glycolyzates and also to conventional general purpose resins.

The glycolytic recycling of waste PET presents a challenge for the production of secondary value-added products, such as alkyd resins. A way to overcome the unsatisfactory mechanical, drying and chemical resistance properties of alkyds obtained from difunctional glycolyzates was proposed. Waste PET was glycolyzed using multifunctional alcohols: glycerol (G), trimethylolethane (TME), trimethylolpropane (TMP) and pentaerythritol (PE), giving tetra-and hexa-functional glycolyzates and, for comparison, using diethylene glycol (DEG), propylene glycol (PG) and dipropylene glycol (DPG) giving di-functional glycolyzates. The obtained glycolyzates were examined by H-1 and C-13 NMR, FTIR spectroscopy and elemental analysis and further used in the synthesis of alkyd resins. The properties of the prepared alkyd resins (acid, hydroxyl and iodine values, color, average molar masses and molar mass distributions, viscosity, drying time, hardness, flexibility, gloss, adhesion and chemical resistance) were investigated with respect to the functionality and the structure of the used glycolyzates. Alkyd resins derived from multifunctional glycolyzates (TME and TMP) showed considerably enhanced properties compared to those produced from difunctional glycolyzates and also to conventional general purpose resins.

Highly crystalline amylose–polytetrahydrofuran (PTHF) complexes can be obtained by employing organic solvents as washing agents after complex formation. The X-ray diffraction (XRD) of the washed complexes appear sharp at 12.9°–13.2° and 19.6°–20.1°, clear signs of the presence of V6I-amylose. Other diffraction peaks correlate with V6II-amylose, which indicates that the complexed amylose helices are in the form of an intermediate or a mixture of V6I- and V6II-amylose. SEM imaging reveals that the amylose–PTHF complexes crystallize in the form of lamellae, which aggregate in a round shape on top of one another with a diameter around 4–8 µm. Some lamellas aggregate as flower-like or flat-surface spherulitic crystals. There is a visible matrix in between the aggregated lamellas which shows that a part of the amylose–PTHF complexes is amorphous.

Nanoporous metal foams possess a unique combination of properties - they are catalytically active, thermally and electrically conductive, and furthermore, have high porosity, high surface-to-volume and strength-to-weight ratio. Unfortunately, common approaches for preparation of metallic nanostructures render materials with highly disordered architecture, which might have an adverse effect on their mechanical properties. Block copolymers have the ability to self-assemble into ordered nanostructures and can be applied as templates for the preparation of well-ordered metal nanofoams. Here we describe the application of a block copolymer-based supramolecular complex -polystyrene-block-poly(4-vinylpyridine)(pentadecylphenol) PS-b-P4VP(PDP) - as a precursor for well-ordered nickel nanofoam. The supramolecular complexes exhibit a phase behavior similar to conventional block copolymers and can self-assemble into the bicontinuous gyroid morphology with two PS networks placed in a P4VP(PDP) matrix. PDP can be dissolved in ethanol leading to the formation of a porous structure that can be backfilled with metal. Using electroless plating technique, nickel can be inserted into the template's channels. Finally, the remaining polymer can be removed via pyrolysis from the polymer/inorganic nanohybrid resulting in nanoporous nickel foam with inverse gyroid morphology.

Nanoporous metal foams possess a unique combination of properties - they are catalytically active, thermally and electrically conductive, and furthermore, have high porosity, high surface-to-volume and strength-to-weight ratio. Unfortunately, common approaches for preparation of metallic nanostructures render materials with highly disordered architecture, which might have an adverse effect on their mechanical properties. Block copolymers have the ability to self-assemble into ordered nanostructures and can be applied as templates for the preparation of well-ordered metal nanofoams. Here we describe the application of a block copolymer-based supramolecular complex -polystyrene-block-poly(4-vinylpyridine)(pentadecylphenol) PS-b-P4VP(PDP) - as a precursor for well-ordered nickel nanofoam. The supramolecular complexes exhibit a phase behavior similar to conventional block copolymers and can self-assemble into the bicontinuous gyroid morphology with two PS networks placed in a P4VP(PDP) matrix. PDP can be dissolved in ethanol leading to the formation of a porous structure that can be backfilled with metal. Using electroless plating technique, nickel can be inserted into the template's channels. Finally, the remaining polymer can be removed via pyrolysis from the polymer/inorganic nanohybrid resulting in nanoporous nickel foam with inverse gyroid morphology.

Amy lose brushes were synthesized by enzymatic polymerization with glucose-l-phosphate as monomer and rabbit muscle phosphorylase b as catalyst on gold-covered surfaces of a quartz crystal microbalance. Fourier transform infrared (FT-IR) spectra confirmed the presence of the characteristic absorption peaks of amylose between 3100 cm(-1) and 3500 cm(-1). The thickness of the amylose brushes-measured by Spectroscopic Ellipsometry-can be tailored from 4 to 20 nm, depending on the reaction time. The contour length of the stretched amylose chains on gold surfaces has been evaluated by single molecule force spectroscopy, and a total chain length of about 20 nm for 16.2 nm thick amylose brushes was estimated. X-ray photoelectron spectroscopy (XPS) was employed to characterize the amylose brushes before and after the adsorption of fatty acids. The dynamics of inclusion complex formation between amylose brushes and two fatty acids (octanoic acid and myristic acid) with different chain length was investigated as a function of time using a quartz crystal microbalance with dissipation monitoring (QCM-D) immersed in the liquid phase. QCM-D signals including the frequency and dissipation shifts elucidated the effects of the fatty acid concentration, the solvent types, the chain length of the fatty acids and the thickness of the amylose brushes on the dynamics of fatty acid molecule adsorption on the amylose brush-modified sensor surfaces.

The phase behavior of block copolymer based supramolecular complexes polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) and amphiphilic pentadecylphenol (PDP) molecules resembles the phase behavior of conventional block copolymers. Several PS-b-P4VP(PDP) complexes are found to self-assemble into gyroid nanostructures. Typically, the grains are randomly oriented with a maximal size of several micrometers. Here, the orientation of a gyroid PS-b-P4VP(PDP) complex upon shearing is reported. It is found that the (111) gyroid lattice direction orients parallel to the shear direction after only several seconds of large amplitude oscillatory shearing. Oriented gyroid complexes can be used as templates for the preparation of metal nanofoams with improved ordering with potentially superior properties.

Amylose and polytetrahydrofuran (PTHF) are mixed in an aqueous solution to form inclusion complexes. DSC shows that immediate mixing results in complexes having lower melting temperatures compared with complexes prepared with longer mixing times. The washed complexes melt at higher temperatures compared with the corresponding unwashed complexes. XRD indicates that amylose-PTHF complexes diffract similar to amylose-fatty acids complexes (V6I-amylose helices), with additional diffractions correlating with amylose-alcohol complexes (V6II-amylose helices). This suggests that the structure of amylose-PTHF complexes is an intermediate or a mixture between V6I- and V6II-amylose. This shows that, besides residing inside the amylose helices, some PTHF chains are located in between the amylose helices.

An in vitro enzyme-catalyzed tandem reaction using the enzymes phosphorylase b from rabbit muscle and Deinococcus geothermalis glycogen branching enzyme (Dg GBE) to obtain branched polyglucans with tunable degree of branching (2% divided by 13%) is presented. The tunable degree of branching is obtained by varying the reaction conditions such as pH value, the choice of reducing agent and its concentration and reaction time. Linear amylose is formed by the phosphorylase-catalyzed propagation of glucose1-phosphate while Dg GBE introduces branching points on the alpha(1 -> 6) position by relocating short oligosaccharide chains. Our results show that the best way to obtain different degrees of branching with this set of enzymes is by regulation of the reaction time. (C) 2012 Elsevier Ltd. All rights reserved.

The sulfinyl precursor route for the synthesis of poly(p-phenylene vinylene) (PPV) materials via an anionic polymerization procedure employing dedicated initiators is evaluated in depth. Reaction kinetics are investigated to gain more control over the polymerization, since polymerization proceeds to full conversion already on the timescale of mixing of the reaction components. Even at -78 degrees C almost full conversion of the monomer is observed after few seconds. BEH-PPVs are obtained in the range of 3000 to 16,000 g mol(-1), whereby dispersity decreases with decreasing molecular weight, allowing for materials with a PDI of 1.1 for the smallest PPV chain. Block copolymerizations were performed via sequential addition of monomers to make use of the living PPV chain ends. Bimodal product mixtures are obtained, consisting of block copolymer as well as PPV homopolymer. The block copolymer PPV-b-poly(tert-butyl acrylate) could nevertheless be separated by selective precipitation as well as preparative chromatography techniques. (c) 2013 Elsevier Ltd. All rights reserved.

The fabrication of nanoporous poly(vinylidene fluoride) (PVDF) and PVDF/nickel nanocomposites from semicrystalline block copolymer precursors is reported. Polystyrene-block-poly(vinylidene fluoride)-block-polystyrene (PS-b-PVDF-b-PS) is prepared through functional benzoyl peroxide initiated polymerization of VDF, followed by atom transfer radical polymerization (ATRP) of styrene. The crystallization of PVDF plays a dominant role in the formation of the block copolymer structure, resulting in a spherulitic superstructure with an internal crystalline-amorphous lamellar nanostructure. The block copolymer promotes the formation of the ferroelectric beta-polymorph of PVDF. Selective etching of the amorphous regions with nitric acid leads to nanoporous PVDF, which functions as a template for the generation of PVDF/Ni nanocomposites. The lamellar nanostructure and the beta-crystalline phase are conserved during the etching procedure and electroless nickel deposition.

Supramolecular complexes of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymers and small molecules such as pentadecylphenol (PDP) have been studied extensively in recent years. In the present study, PS-b-P4VP(PDP) complexes with a minority P4VP(PDP) block are morphologically characterized focusing on the region between the lamellar and cylindrical phase. Dynamic mechanical measurements and small-angle X-ray scattering are used to follow the transitions between the ordered states upon heating/cooling. The self-assembled state at various temperatures is determined by small-angle X-ray scattering and transmission electron microscopy. In contrast to the opposite case of majority P4VP(PDP) blocks, where the transition from lamellar to cylindrical structures frequently occurs via the gyroid morphology, the complexes adopt the hexagonally perforated layered morphology in a broad range of compositions. Although known as a metastable phase in pure diblock copolymers, the hexagonally perforated layered phase appears as an equilibrium phase in PS-b-P4VP(PDP) complexes, being stabilized by the presence of the hydrogen-bonded PDP side chains in the minority component domains.

The double gyroid network morphology has been the focus of extensive research efforts as one of the most appealing block copolymer structures for practical applications. We performed an extensive study of the phase behavior of the supramolecular complex PS-b-P4VP(PDP)(x) to develop a systematic route to its double gyroid morphology. The morphological characterization of complexes was accomplished by transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). Several compositions with the cubic Ia(3)over bard symmetry were found in a narrow region between the lamellar and the cylindrical phase. Experimental TEM images were compared to computer simulations of projections through multiple gyroid planes. Typical gyroid patterns "double wave" and "wagon wheel" were regularly found. The size of the gyroid unit cell was calculated from the SAXS data. The lattice parameter could be varied (from ca. 70 to 125 nm) by altering the molar mass of the block copolymer precursors. A number of complexes were found to exhibit characteristic biphasic morphologies coexisting lamellar and gyroid phase or gyroid and cylindrical phase. Finally, gyroid complexes with different relative PDP ratios were obtained which provides the opportunity to generate nanoporous structures with tunable porosities by dissolving the amphiphiles.

Biotechnology also holds tremendous opportunities for realizing functional polymeric materials. Biocatalytic pathways to polymeric materials are an emerging research area with not only enormous scientific and technological promise, but also a tremendous impact on environmental issues. Many of the enzymatic polymerizations reported proceed in organic solvents. However, enzymes mostly show none of their profound characteristics in organic solvents and can easily denature under industrial conditions. Therefore, natural enzymes seldom have the features adequate to be used as industrial catalysts in organic synthesis. The productivity of enzymatic processes is often low due to substrate and/or product inhibition. An important route to improving enzyme performance in non-natural environments is to immobilize them. In this review we will first summarize some of the most prominent examples of enzymatic polymerizations and will subsequently review the most important immobilization routes that are used for the immobilization of biocatalysts relevant to the field of enzymatic polymerizations.

Biotechnology also holds tremendous opportunities for realizing functional polymeric materials. Biocatalytic pathways to polymeric materials are an emerging research area with not only enormous scientific and technological promise, but also a tremendous impact on environmental issues. Many of the enzymatic polymerizations reported proceed in organic solvents. However, enzymes mostly show none of their profound characteristics in organic solvents and can easily denature under industrial conditions. Therefore, natural enzymes seldom have the features adequate to be used as industrial catalysts in organic synthesis. The productivity of enzymatic processes is often low due to substrate and/or product inhibition. An important route to improving enzyme performance in non-natural environments is to immobilize them. In this review we will first summarize some of the most prominent examples of enzymatic polymerizations and will subsequently review the most important immobilization routes that are used for the immobilization of biocatalysts relevant to the field of enzymatic polymerizations.

A series of poly(GMA-co-EGDMA) resins with identical composition but varying particle sizes, pore radii, specific surface areas and specific volumes are studied to assess how Candida antarctica lipase B immobilization affects the porosity of the copolymer particles. Mercury porosimetry reveals a significant change in the average pore size (up to 6.1-fold), the specific surface area (up to 3.2-fold) and the specific volume (up to 2.1-fold) of the epoxy resin. A similar behaviour is observed for glutaraldehyde-modified epoxy resins. The influences of the resin porosity properties on the loading of Candida antarctica lipase B during immobilization and on the hydrolytic activity (hydrolysis of p-nitrophenyl acetate) of the immobilized lipase are studied.

Metal nanofoams with a porosity above 50% v/v have recently attracted great. Interest In materials science due to their interesting properties.. We.. demonstrate a new straightforward route to prepare such nanofoams using diblock copolymer-based PS-block-P4VP-(PDP) supramolecules that self-assemble Into a bicontinuous gyroid morphology, consisting of PS network channels in a P4VP(PDP) matrix. After dissolving the PDP, the P4VP. collapses onto the PS struts and a free-standing bicontinuous. gyroid template of 50-100 mu m thickness and interconnected, uniformly sized pores Is formed. The hydrophilic P4VP corona facilitates the penetration of water-based plating reagents into the porous template and enables a successful metal deposition. After plating, the polymer is simply degraded by heating, resulting In a well-ordered inverse gyroid nickel-foam. Essential to this approach Is the removal of only one part of the matrix (i.e., PDP). Therefore, the template accounts for 50% v/v or more. The porosity characteristics (amount, size of pores) can be tuned by selecting the appropriate copolymer and by adjusting the amount of PDP.

Supramolecular complexes of a poly(tert-butoxystyrene)-block-polystyrene-block-poly(4-vinylpyridine) triblock copolymers and less than stoichiometric amounts of pentadecylphenol (PDP) are shown to self-assemble into a core-shell gyroid morphology with the core channels formed by the hydrogen-bonded P4VP(PDP) complexes. After structure formation, PDP was removed using a simple washing procedure, resulting in well-ordered nanoporous films that were used as templates for nickel plating.

Supramolecular complexes of a poly(tert-butoxystyrene)-block-polystyrene-block-poly(4-vinylpyridine) triblock copolymers and less than stoichiometric amounts of pentadecylphenol (PDP) are shown to self-assemble into a core-shell gyroid morphology with the core channels formed by the hydrogen-bonded P4VP(PDP) complexes. After structure formation, PDP was removed using a simple washing procedure, resulting in well-ordered nanoporous films that were used as templates for nickel plating.

A series of poly(GMA-co-EGDMA) resins with identical composition but varying particle sizes, pore radii, specific surface areas and specific volumes are studied to assess how Candida antarctica lipase B immobilization affects the porosity of the copolymer particles. Mercury porosimetry reveals a significant change in the average pore size (up to 6.1-fold), the specific surface area (up to 3.2-fold) and the specific volume (up to 2.1-fold) of the epoxy resin. A similar behaviour is observed for glutaraldehyde-modified epoxy resins. The influences of the resin porosity properties on the loading of Candida antarctica lipase B during immobilization and on the hydrolytic activity (hydrolysis of p-nitrophenyl acetate) of the immobilized lipase are studied.

Metal nanofoams with a porosity above 50% v/v have recently attracted great. Interest In materials science due to their interesting properties.. We.. demonstrate a new straightforward route to prepare such nanofoams using diblock copolymer-based PS-block-P4VP-(PDP) supramolecules that self-assemble Into a bicontinuous gyroid morphology, consisting of PS network channels in a P4VP(PDP) matrix. After dissolving the PDP, the P4VP. collapses onto the PS struts and a free-standing bicontinuous. gyroid template of 50-100 mu m thickness and interconnected, uniformly sized pores Is formed. The hydrophilic P4VP corona facilitates the penetration of water-based plating reagents into the porous template and enables a successful metal deposition. After plating, the polymer is simply degraded by heating, resulting In a well-ordered inverse gyroid nickel-foam. Essential to this approach Is the removal of only one part of the matrix (i.e., PDP). Therefore, the template accounts for 50% v/v or more. The porosity characteristics (amount, size of pores) can be tuned by selecting the appropriate copolymer and by adjusting the amount of PDP.

The functionalization of magnetite (Fe3O4) nanoparticles with dopamine-derived clickable biomimetic anchors is reported. Herein, an alkyne-modified catechol-derivative is employed as the anchor, as i) the catechol-functional anchor groups possess irreversible covalent binding affinity to Fe3O4 nanoparticles, and ii) the alkyne terminus enables further functionalization of the nanoparticles by the grafting-onto approach with various possibilities offered by 'click' chemistry. In the present work, azido-end group functionalized Rhodamine and poly(ethylene glycol) (PEG) are utilized to coat the iron oxide nanoparticles to make them fluorescent and water soluble.

We present a rapid synthetic method for the development of hyperbranched PEIs decorated with different oligosaccharide architectures as carrier systems (CS) for drugs and bioactive molecules for in vitro and in vivo experiments. Reductive amination of hyperbranched PEI with readily available oligosaccharides results in sugar functionalized PEI cores with oligosaccharide shells of different densities. These core-shell architectures were characterized by NMR spectroscopy, elemental analysis, SLS, DLS, IR, and polyelectrolyte titration experiments. ATP complexation of theses polycations was examined by isothermal titration calorimetry to evaluate the binding energy and ATP/CS complexation ratios under physiological conditions. In vitro experiments showed an enhanced cellular uptake of ATP/CS complexes compared to those of the free ATP molecules. The results arise to initiate further noncovalent complexation studies of pharmacologically relevant molecules that may lead to the development of therapeutics based on this polymeric delivery platform.

We report the functionalization of cross-linked poly(divinylbenzene) (pDVB) microspheres using both thiol-ene chemistry and azide-alkyne click reactions. The RAFT technique was carried out to synthesize SH-functionalized poly(N-isopropylacrylimide) (pNIPAAm) and utilized to generate pNIPAAm surface-modified microspheres via thiol-ene modification. The accessible double bonds on the surface of the microspheres allow the direct coupling with thiol-end functionalized pNIPAAm. In a second approach, pDVB microspheres were grafted with poly(2-hydroxyethyl methacrylate) (pHEMA). For this purpose, the residual double bonds on the microspheres surface were used to attach azide groups via the thiol-ene approach of 1-azido-undecane-11-thiol. In a second step, alkyne endfunctionalized pHEMA was used to graft pHEMA to the azide-modified surface via click-chemistry (Huisgen 1,3-dipolar cycloaddition). The surface-sensitive characterization methods X-ray photoelectron spectroscopy, scanning-electron microscopy and FT-IR transmission spectroscopy were employed to characterize the successful surface modification of the microspheres. In addition, fluorescence microscopy confirms the presence of grafted pHEMA chains after labeling with Rhodamine B.