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Renewable 3-allyl-5-vinylveratrole (AVV) has been evaluated and classified as a biobased cross-linkable vinyl monomer in free-radical chain polymerization. AVV can be readily synthesized in four st...

A new tubular electrochemical system (TES) was developed to overcome scalability and sustainability challenges during synthesis of superparamagnetic iron oxide (Fe3O4) nanoparticles (SPIONs). The SPION yield and productivity were 8.3 mg mol−1 Fe and 163 µg mol−1 Fe min−1, respectively. The TES functions efficiently with electrolyte reuse and supplementation without any reduction in productivity. Gradual electrolyte supplementation (0.5 mL min−1) resulted in 75% higher yield than the non-supplemented system. TEM and XRD analyses confirmed the presence of Fe3O4. TES enables the use of a new reaction parameter—flow rate—for controlling SPION properties. Increasing electrolyte flow rate caused a decrease in SPION average size and size distribution. TES offers advantages of scalability and sustainability for large-scale production of Fe3O4 nanoparticles.

This work reports on the development of biomimetic polymeric cellulosomes—enzyme–polymer conjugates (EPCs) generated by covalent binding of cellulase enzymes onto a molecular brush polymer scaffold...

Magnetic nanobiocatalysts (MNBCs) are a promising immobilization approach to ease enzyme recovery during bioprocessing. However, industrial adoption of MNBCs is unfeasible because MNBC-synthesis involves complex and potentially expensive processing steps including synthesis of silica-coated superparamagnetic iron oxide nanoparticles (Si-SPIONs). We developed a single-step process for Si-SPION synthesis using a tubular electrochemical system (TES) and investigated the effect of concentration of the Na

Plant-based proteins are attractive components which may serve as sustainable alternatives to current petrochemical products. Both soy protein and major corn protein, zein, are of interest in food packaging applications due to their sustainability, biodegradation properties, and inherent physicochemical properties. This study discusses the development of bioplastic materials, where it explores the effects of combining zein, soy protein, and plasticizing latexes derived from plant oil-based monomers (POBMs) on properties of resulting bioplastic films. By looking for synergistic effects of soy protein's inherent film formation ability and zein's higher strength, we prepare strong yet flexible soy-zein films as materials, called proteoposites. Incorporation of natural additive POBM-latexes helps to plasticize and hydrophobize the bioplastic films and thus to improve mechanical and barrier properties. Variation of the POBM-latexes' particle size further aims to enhance the performance of resulting bioplastic films. As a result, modified soy-zein proteoposite films with improved moisture resistance, enhanced mechanical behavior, and greater barrier properties were developed. Machine learning-based computational models were utilized in order to find main structural factors affecting the bioplastic's properties and develop a quantitative structure-property relationship model between the physicochemical properties of the film components and the resulted bioplastics' properties and performance. The developed model effectively predicts experimental outcomes with85% (

Improving the sustainability of polymeric materials through integrating biobased components while maintaining their functionality can be challenging. Using plant oils for the synthesis of biobased ...

Highly hydrophobic vinyl monomers from soybean (SBM) and olive (OVM) oil with different amounts of unsaturation were copolymerized in emulsion with significantly more soluble in water comonomers, methyl methacrylate (MMA), vinyl acetate (VA), and methyl acrylate (MA). Our intention was to demonstrate that higher aqueous solubility of the comonomer impacts the mechanism of the emulsion process by balancing latex particle homogeneous and heterogeneous (micellar) nucleation. Using an experimental method based on water insoluble dye Blue 70, it is shown that particle nucleation indeed depends to a great extent on aqueous solubility of the comonomer, along with the plant oil-based monomer (POBM) content in the feed. Upon addition of POBM into the monomer mixture with MMA (aq.solubility 1.5 wt%), the latex polymer particles originating from micellar nucleation essentially increased. In copolymerization of POBM with MA (aqueous solubility 4.9 wt%), this effect is even more pronounced. Those findings clearly indicate that copolymerization loci change when monomer feed hydrophobicity increases, and the magnitude of this effect is dependent on the comonomer aqueous solubility. Experimentally determined changes in reaction order with respect to emulsifier and initiator upon addition of POBM confirm that kinetics of emulsion copolymerization is impacted by comonomer aqueous solubility. The latter finding can be indicative of changing latex particle nucleation mode when monomer feed hydrophobicity changes. Overall, the portion of latex particles originating through micellar nucleation is higher in the copolymerization of more unsaturated SBM (with both MMA and MA) in comparison to OVM. No impact of POBM content on the reaction kinetics was observed in copolymerization with VA (aq. solubility 2.5 wt%). Here, high reactivity of growing PVA radicals in chain transfer reactions makes the presence of POBM in monomer feed kinetically irrelevant.

The effect of highly hydrophobic olive oil-based (OVM) and high oleic soybean oil-based (HO-SBM) acrylic monomers on micellization of sodium dodecyl sulfate (SDS) was examined at different surfactant and monomer concentrations by determining micellar parameters, size and structure, as well as surface tension measurements. The obtained results indicate SDS ability to solubilize sparingly soluble in water plant oil-based monomer (POBM) molecules and facilitate formation of mixed (SDS/POBM) micelles. Surface activity of a surfactant/monomer mixture varies by adding the POBM and is generally higher than for SDS. Comprehensive trends were observed for micellar aggregation number and number of micelle-bound monomer molecules demonstrating that POBM molecules replace SDS counterparts in the mixed micelles. Based on dynamic light scattering measurements (DLS), we hypothesized that incorporation of POBM into the mixed micelles promotes micellar association and formation of 25–30 nm size structures, also detected using transmission electron microscopy (TEM). Practical importance of these findings is the fact that solubilization of POBM by surfactant molecules can have an impact on reaction kinetics and mechanism of emulsion polymerization, as well as affect latex particles formation and, respectively, resulting particle morphology.

International audience; Along with characterization of vinyl monomers from high oleic soybean oil (HOSBM) and cardanol (CBM) in free radical (co)polymerization, a series of stable latexes based on various ratios of these fully renewable plant-based monomer mixtures have been synthesized using a miniemulsion process. The combination of aliphatic fatty acid fragments of HOSBM with aromatic CBM structure led to the formation of durable latexes from fully renewable feeds as well as the ability of the resulting cross-linked latex films to balance thermomechanical properties. Biobased latexes were synthesized from 10 to 75 wt % of CBM and 25–90 wt % of HOSBM in the feed, characterized, and tested in films and coatings performances. The synergistic effects of both the constituents in the films and coatings were observed. The incorporation of cardanol-based fragments enhances the Young’s modulus of the films, whereas the plant oil-based units contribute to softer and more flexible films. Even small (10 wt %) fractions of CBM can provide noticeable strength to the soft latex polymer material based entirely on HOSBM. All cross-linked latex films in this study exhibit decent properties and performance in terms of pendulum and pencil hardness, water and solvent resistance, as well as adhesion to the steel substrate. To the best of our knowledge, latexes from fully renewable plant-based monomer mixtures have not been reported before in literature.

Although series of latexes from plant oil-based acrylic monomers (POBMs) were recently synthesized in emulsion, two factors—allylic termination (the chain transfer reaction to the fatty acid double bonds) and the poor aqueous solubility of POBMs—lead to the lower total monomer conversion and molecular weight of the resulting latex polymers. In this study, amphiphilic oligosaccharide, methyl-β-cyclodextrin (M-β-CD), was used to improve the polymerizability of monomers from high oleic soybean (HO-SBM) and linseed (LSM) oil in copolymerization with styrene. Using X-ray diffractometry and differential scanning calorimetry, interactions between the monomers and M-β-CD were confirmed, while the formation of 1:1 complex from oligosaccharide and each monomer molecules was demonstrated by mass spectrometry. In the presence of “host-guest” complexes, polymer yield increases as the coagulum amount drops during the emulsion polymerization of both plant oil-based monomers with styrene indicating their enhanced aqueous solubility. Remarkably, latex polymers with a consistently higher molecular weight were obtained in the presence of M-β-CD. The complex formation and incorporation of monomer molecules into the oligosaccharide cavities protect the fatty acid moieties and diminishes chain transfer. The latter assumption was quantitatively confirmed in 1H NMR spectroscopy by determining the number of protons of the alkyl carbon−carbon double bonds (–CH = CH–) and the bisallylic hydrogen atoms (–CH = CH–CH2–CH = CH–) in the unsaturated fatty acid moieties of the latex copolymers. The observed effect is more pronounced for more unsaturated monomer from linseed oil. Based on the obtained results, M-β-CD plays a dual role in both enhancing POBM polymerizability as well as protecting against allylic termination chain transfer.

In recent years, polymer chemistry has experienced an intensive development of a new field regarding the synthesis of aliphatic and aromatic biobased monomers obtained from renewable plant sources. A one-step process for the synthesis of new vinyl monomers by the reaction of direct transesterification of plant oil triglycerides with N-(hydroxyethyl)acrylamide has been recently invented to yield plant oil-based monomers (POBMs). The features of the POBM chemical structure, containing both a polar (hydrophilic) fragment capable of electrostatic interactions, and hydrophobic acyl fatty acid moieties (C15-C17) capable of van der Waals interactions, ensures the participation of the POBMs fragments of polymers in intermolecular interactions before and during polymerization. The use of the POBMs with different unsaturations in copolymerization reactions with conventional vinyl monomers allows for obtaining copolymers with enhanced hydrophobicity, provides a mechanism of internal plasticization and control of crosslinking degree. Synthesized latexes and latex polymers are promising candidates for the formation of hydrophobic polymer coatings with controlled physical and mechanical properties through the targeted control of the content of different POBM units with different degrees of unsaturation in the latex polymers.

[Image: see text] Conventional treatment approaches fail to provide durable control over aggressive malignancies due to intrinsic or acquired drug resistance characteristic of high-risk disease. SN-38, a potent camptothecin analog specifically targeting DNA topoisomerase I cleavage complexes, has shown promise in preclinical studies against aggressive solid tumors. However, its clinical utility is limited by inadequate solubility in pharmaceutically acceptable vehicles and by poor chemical and metabolic stability. Micelles formulated from amphiphilic invertible polymers (AIPs) can address these issues by concomitantly enabling solubilization of water-insoluble molecular cargoes and by protecting chemically labile agents from inactivation. Furthermore, the inversion of the AIP and disruption of the carrier–drug complexes triggered by contact with cell membranes makes it possible to deliver the therapeutic payload into the cell interior without compromising its biological activity. In the present study, we characterized a novel AIP-based micellar formulation of SN-38 and evaluated its growth inhibitory effect on neuroblastoma (NB) cells derived either at diagnosis or at relapse after intensive chemoradiotherapy. Colloidally stable, drug-loaded micellar assemblies with a uniform

Enzyme immobilization has been identified as one way to recycle enzymes and reduce processing costs during enzymatic hydrolysis of lignocellulosic materials. However, most immobilization methods have not been attractive to lignocellulosic processing plants. In this study, cellulase enzymes were attached to a copolymer of glycidyl methacrylate (GMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) to make polymer-enzyme conjugates (PECs) and facilitate recovery using a 50-kDa molecular weight cutoff membrane. Glucan conversion during biomass hydrolysis was investigated using new PECs and PECs recovered after an initial hydrolysis stage. Enzyme immobilization on PECs did not reduce effectiveness during the initial hydrolysis. Temperature and pH showed similar effects on free enzymes and PECs. PECs facilitated higher conversion rates than free enzymes at high biomass loadings. Recovered PECs were used to achieve approximately 100% glucan conversion in a subsequent hydrolysis step when supplemented with 40% of the free enzyme used in the first stage. The combination of PECs and membrane recovery has the potential to reduce hydrolysis cost during cellulosic bioprocessing.

Fourier transform infrared (FTIR) microspectroscopy provides a biochemical fingerprint of the cells. In this study, chemical changes in 143B osteosarcoma cells were investigated using FTIR analysis of cancer cells after their treatment with polymeric invertible micellar assemblies (IMAs) and curcumin-loaded IMAs and compared with untreated osteosarcoma cells. A comprehensive principal component analysis (PCA) was applied to analyze the FTIR results and confirm noticeable changes in cell surface chemical structures in the fingerprint regions of 1480–900 cm−1. The performed clustering shows visible differences for all investigated groups of cancer cells. It is demonstrated that a combination of FTIR microspectroscopy with PCA can be an efficient approach in determining interactions of osteosarcoma cells and drug-loaded polymer micellar assemblies.

Extracting, stabilizing, or delivering biomacromolecules such as proteins and peptides in organic phases have potential applications in biocatalysis, protein extraction, and food antioxidation. However, most current delivery/stabilization platforms face various limitations such as protein/peptide molecular size, platform stability/reusability, and/or potential damage to the cargos. A potential solution to these problems is micellar self-assemblies from amphiphilic invertible polymers, which have recently been demonstrated to be powerful as molecular hosts to deliver both small molecular drugs and functional polypeptides in the aqueous phase. To better understand the function of biomacromolecules and predict the usefulness of the formed invertible micellar assemblies (IMAs) as biomacromolecular hosts in organic phases, it is critical to characterize the spatial distribution, structure, and dynamics of biomacromolecules in the IMA including those upon release. However, the background signals of the IMAs limit the application of most peptide characterization approaches. In this work, we overcome the technical barriers by using site-directed spin labeling electron paramagnetic resonance to probe the spatial arrangement and release of a model, the hemagglutinin (HA) peptide, in the IMAs formed from two different amphiphilic invertible polymers. By site-specifically probing three residues along the peptide chain, for the first time, we depict the possible spatial distribution of HA within the IMAs. By triggering the disassembly of the IMAs with a thermodynamically good solvent (in this study, acetone), we detailed the stability of IMAs in toluene and the peptide release conditions once the polarity of the medium changes. Our findings are important for the application of peptides/proteins at the polar-nonpolar interface or using this interface to extract or deliver biomacromolecules. Our work also demonstrates the power of SDSL-EPR on probing peptide or micelle dynamics, which can be generalized to understand proteins or other biomacromolecules in micellar polymer assemblies in varied applications.

Chitosan (Chit) and its derivatives have received much attention due to their biodegradability, non-toxicity, and biocompatibility along with their antimicrobial, antiviral, and antitumoral activity. The preparation of three-dimensional chitosan-based polymer structures is usually conducted through the formation of ionic, covalent, and hydrogen bonds or hydrophobic interactions using chemical intermolecular cross-linking. The objective of this work is to provide a systematic review of recent studies by various research groups on three-dimensional polymer chitosan structures for biomedical applications, drug delivery, cosmetics. The introduction of a peroxide –OO– group into the chitosan macromolecule, achieved by the authors of this review, allows for the formation of three-dimensional structures of chitosan derivatives through radical and ionic mechanisms. To the best of our knowledge, there is no information in the literature on peroxide derivatives of Chit synthesized through the reactions of the amino group other than the above-mentioned works. Radical reactions were initiated by a controlled decomposition of the peroxide groups in peroxychitosans (PChit) in order to form a three-dimensional polymer matrix. PChit were synthesized by the method of polymer-analogous reaction through the peroxidation of chitosan with tert-butylperoxymethyl maleate. pH-sensitive macrohydrogels with a covalently cross-linked three-dimensional polymer matrix were developed by graft copolymerization of 1-vinyl-2-pyrrolidone and PChit in an aqueous medium. The pH-sensitive macrogels absorb and release an antibiotic cefazolin depending on pH and can be grafted to a cotton fabric. pH-sensitive spherical hydrogel nanoparticles were synthesized in aqueous nanodroplets of a reverse emulsion via free-radical graft copolymerization of 1-vinyl-2-pyrrolidone and PChit with primary-tertiary peroxide groups. The formed nanogels were loaded with anionic or cationic fluorescent dyes as drug models. The swelling and release profiles depend on polymer-network density, nature of the dye, and pH. Peroxychitosan was synthesized through the radical interaction between chitosan and a peroxide monomer followed by the emulsion polymerization of vinyl monomers in the presence of peroxychitosan. Self-assembled pH-sensitive submicron particles were formed due to the intermolecular electrostatic interaction between the ammonium groups of chitosan and the carboxylate groups of peroxide-containing oligooxyethylene pyromellitate (OOP). The particles have the structure of an ionically cross-linked hydrogel, their size and surface charge depending on pH and the ratio of the functional groups. The presence of the OOP peroxide groups allowed for further synthesis of covalently cross-linked pH-sensitive nanoparticles. The three-dimensional polymer structures of chitosan and its derivatives are promising candidates for the development of polymer drug-delivery systems, cosmetics, antibacterial coatings.

As the concentration of amphiphilic invertible polymers (AIPs) in both polar and nonpolar solvents increases, the AIP macromolecules self-assemble into polymeric micelles. The resulting invertible ...

Amino acid esters are widely used for biomedical applications due to their combination of the unique properties of each functional group. These include biocompatibility, biodegradability and low to...

A series of latexes from acrylic monomers (made from olive, soybean, linseed, and hydrogenated soybean oils), significantly different in terms of fatty acid unsaturation, were synthesized using miniemulsion copolymerization with styrene. The number-average molecular weight and the glass transition temperature of the resulting copolymers with high levels of biobased content (up to approximately 60 wt %) depend essentially on the amount of unsaturation (the number of double bonds in triglyceride fatty acid fragments of plant oil-based monomers) in the reaction feed. When plant oil-based latex films are oxidatively cured, the linear dependence of the cross-link density on reaction feed unsaturation is observed. Dynamic mechanical and pendulum hardness measurements indicate that the properties of the resulting plant oil-based polymer network are mainly determined by cross-link density. On the basis of the linear dependence of the cross-link density on monomer feed unsaturation, it can be concluded that the la...

Sucrose octasoyate (SS8) was investigated as a reactive diluent for a medium oil alkyd (MOA). SS8, which is derived from sugar and soybean oil, is 100% biobased, nontoxic, and biodegradable. As a result of its unique molecular architecture, it was expected that SS8 would be an excellent reactive diluent for alkyd coatings. The experiment conducted basically involved the incremental replacement of the MOA with SS8, while maintaining essentially equivalent solution viscosity. The properties of cured coatings were determined using industry standard methods. In general, it was found that SS8 could be used to reduce volatile organic compound content of the coatings, while also reducing drying time (i.e., tack-free time), increasing solvent resistance, and increasing impact resistance. Of the properties measured, the only cured film property that was negatively affected by the use of SS8 was the Konig pendulum hardness. However, the reduction in Konig pendulum hardness was only observed when the amount of MOA replaced by SS8 was greater than 10 wt%. Overall, these initial results suggest that SS8 is a very good reactive diluent for alkyd coatings.

Vinyl monomers from plant oils that have different degrees of unsaturation, soybean (SBM), and olive (OVM) oil were copolymerized in emulsion with styrene to investigate the kinetics features and feasibility of latex formation. In the presence of up to 20 wt% of SBM/OVM in the initial feed, the order of reaction with respect to the emulsifier and initiator do not depend on the plant oil-based monomers’ unsaturation degree. Reaction kinetics agree with the Smith-Ewart theory, predicting that the number of nucleated latex particles is proportional to the surfactant and initiator concentration to the powers 0.6 and 0.4, respectively. Copolymerization of styrene with plant oil-based monomers follows the typical phenomenology for emulsion polymerization of hydrophobic monomers with a micellar nucleation mechanism. Nevertheless, based on experimentally obtained latex particles’ size and number, evidence for a mixed mode of nucleation (both micellar and homogeneous) was observed in this research. Mixed nucleation can be explained by the potential surface-active properties of plant oil-based monomer molecules containing polar acryloylamino “head,” CH2 CH C(O) NH and hydrophobic “tail,” C17). Because of the effect of the degradative chain transfer on the plant oil-based monomer, the molecular weight of the resulting macromolecules decreases as the monomer degree of unsaturation and monomer fraction in the initial mixture increases. This feature can be used for controlling the molecular weight of latex polymers that come from plant oil-based monomers by varying the content and nature of bio-based monomer in feed. The thermomechanical properties of latex films depend considerably on the nature and amount of incorporated plant oil-based fragments. Their presence lowers Tg (more than 40 °C difference) and provides some flexibility and toughness as compared to the normally rigid and brittle polystyrene.

The interaction of binary copolymers poly(maleic anhydride-co-poly(ethylene glycol) methyl ether methacrylate) with cholesterol results in formation of cholesterol containing polymers, which contain from 4.6 to 46.0 mol % monocholesteryl maleic links. Their structure was confirmed using functional analysis and IR spectroscopy. Acidic and anhydride links of these copolymers form polymeric salts if react with alkali. These salts are surfactants which in aqueous medium form a hierarchy micelles and micellar aggregates depending on the copolymer concentration. Using conductometry it was found that preferably monomolecular micelles are formed in dilute solutions, and micellar aggregates begin to form at higher concentrations. In aqueous media polymeric salts are able to solubilize such lipophilic substances as Sudan III dye and anticancer drug curcumin. Efficiency of solubilization towards Sudan III grows if the content of monocholesteryl maleic fragment in surfactant increases.

Vinyl aromatic monomers derived from dihydroeugenol (EBM) and guaiacol (GBM) were copolymerized, via a miniemulsion process, with aliphatic monomers from high oleic soybean oil (HOSBM), yielding emulsion polymers with higher levels of biobased content. This fully renewable monomer feed generated a broad range of novel latexes, with the number-average molecular weight varying from 25,000–650,000 g/mol. Increasing the content of aromatic biobased monomers heightened the resulting latexes’ molecular weights due to the decreasing unsaturation degree (lower HOSBM content) in the reactive mixture. The monomer feed unsaturation effect was found to be more pronounced for latexes derived from EBMs and HOSBMs because EBMs are more reactive in free radical polymerization compared to GBMs. The presence of oil-derived unsaturated fragments in emulsion polymers provides an opportunity to crosslink resulting latexes in a controlled way to adjust the polymer networks’ thermomechanical properties. Thus, crosslinked films and coatings from latexes made of 25–90 wt.% EBM/GBM and 10–75 wt.% HOSBM were tested. This demonstrated that the characteristics of the resulting biobased latex materials are determined by the nature and ratio of the aliphatic oil residues from HOSBM and the aromatic fragments from EBM/GBM in the macromolecular backbone. Young’s modulus was also higher for the films with greater levels of EBM/GBM, while flexibility of the resulting polymeric materials was found to be determined by soft oil-derived copolymer content. For all films, hardness, impact resistance and adhesion to the steel substrate were evaluated. By combining the aliphatic fatty acid fragments of HOSBM with the aromatic EBM/GBM structure, durable latexes can be synthesized, with the ability to balance the thermomechanical properties of latex polymer networks over a broad range.

(Acryloylamino)ethyl soyate is a soybean oil-based acrylic monomer (SBM) with versatile properties for applications in polymeric materials. To explore the economic feasibility of the bio-based monomers as a potential replacement for the commercial petro-counterpart, this study presents a conceptual process design and scale-up of SBMs production. Process simulation was conducted by Aspen Plus through an integrated design consisting of the catalytic transesterification conversion of soybean oil/soybean oil-based biodiesel with N-hydroxyethyl acrylamide (HEAA), followed by product recovery optimization with solvents recycling solutions. The simulation tool estimated mass and energy balances and assessed plant performance under varying process conditions (different renewable content, catalysts, soybean oil-based feedstocks, and scales). The minimum selling price (MSP) of SBM in the base case was estimated to be $78.4/kg using a cash flow analysis, which shows its economic potential compared to stearyl acrylate. The renewable content of the specialty chemical is a key technical parameter for MSP while it contributes to carbon emission reduction as well. Carbon abatement cost analysis indicates trivial economic impact of feedstock and the need for abatement consideration in different environmental profiles for bio-based chemicals. The uncertainty analysis showed the price of the fossil-based component – HEAA has the major impact on the MSP, while feedstock to HEAA ratio, tax rate, interest rate, and capital cost are sensitive parameters. Underlying areas such as wastewater treatment and economy of scale effects in producing specialty polymers were also discussed in this study.

A one-step method of plant oil direct transesterification was used to synthesize new vinyl monomers from sunflower (SFM), linseed (LSM), soybean (SBM), and olive (OVM) oils. The degree of unsaturation in plant oil fatty acids was used as a criterion to compare the free radical polymerization behavior of new monomers. The number-average molecular weight of plant oil-based homopolymers synthesized in toluene in the presence of AIBN at 75 °C varies at 11 000–25 000 and decreases as follows: poly(OVM) > poly(SFM) > poly(SBM) > poly(LSM), corresponding to increasing degree of unsaturation in the monomers. Rate of polymerization depends noticeably on the degree of unsaturation in monomers. Due to the allylic termination, chain propagation coexists with effective chain transfer during polymerization. The obtained values of CM (ratio of chain transfer and propagation rate constants) depends on monomer structure as follows: CM(LSM) > CM(SBM) > CM(SFM) > CM(OVM). 1H NMR spectroscopy shows that the fraction of the r...

The method for synthesis of a new class of amphiphilic oligoesters of pyromellitic acid is developed. As hydrophilic fragments polyethylene glycols or polyethylene glycol mono methyl ethers were used, as lipophilic ones – primary fatty alcohols or cholesterol. The structure of the synthesized oligoesters was confirmed by IR- and PMR-spectroscopy. The oligoesters could solubilize water-insoluble substances, for example such effective antitumor lipophilic drug as curcumin. The high solubilization capacity of the OEPA assemblies and their biodegradability, as well as other properties (size distribution, ζ-potential) make the oligoesters considered as promising materials for the design of drug delivery systems.

Macromolecules of amphiphilic invertible polymers (AIPs) are capable of self-assembly into micellar assemblies of various morphologies in solvents of different polarities. The micellar assemblies in aqueous media are capable of encapsulating poorly aqueous soluble cargo and can undergo inverse conformational change and cargo release in contact with non-polar media, including potentially, cell membranes. Thus, invertible micellar assemblies have significant potential in drug delivery and related domains. However, to date there have been few investigations into their interactions with lipid membranes. Herein, we investigate the interactions of three recently developed AIPs of varying hydrophobicity/hydrophilicity balance with a highly fluidic microcavity supported 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipid bilayer. We combined electrochemical impedance spectroscopy (EIS) with fluorescence correlation spectroscopy (FCS) to understand how the AIP micellar assemblies impacted bilayer permeability and fluidity respectively, across polymer concentrations above and below their critical micelle concentrations (cmcs). At concentration as above their cmcs, all of the AIPs explored increased permeability and decreased the fluidity of the lipid membrane. The extent of impact depended on the hydrophobicity of the AIP. PEG600-PTHF650, the most hydrophobic of the polymers, synthesized from PEG (molecular weight 600 g/mol) and PTHF (molecular weight 650 g/mol) exerted the greatest influence on the bilayer’s physical properties and fluorescence imaging and correlation data indicate that PEG600-PTHF650 micelles loaded with BODIPY probes adsorb and invert at the lipid membrane with release of cargo into the bilayer. This study should help inform future advancement of AIPs for membrane molecular delivery.

A one-step method that converts soybean oil into (acryloylamino)ethyl soyate, a new vinyl monomer of free radical polymerization, was developed. The synthesized monomer combines a vinyl double bond (acryloyl functional group) and nonconjugated (isolated) double bonds of fatty acids. The double bond of the acryloyl group is reactive in a free radical chain polymerization that yields linear macromolecules containing isolated double bonds in side chains. Monomer reactivity ratios (r1, r2) in copolymerization of the new soybean oil-based acrylic monomer (SBA) with styrene, methyl methacrylate, and vinyl acetate, as well as the Q–e parameters of the SBA, were determined. The obtained results indicate that copolymerization can be described with the classical Mayo–Lewis equation. In terms of polymerizability, the SBA can be classified as an acrylic monomer. The double bonds of the fatty acid chains remain mainly unaffected during the free radical polymerization. The remaining unsaturated fragments in the side ch...

Production costs of cellulosic biofuels can be lowered if cellulases are recovered and reused using particulate carriers that can be extracted after biomass hydrolysis. Such enzyme recovery was recently demonstrated using enzymogel nanoparticles with grafted polymer brushes loaded with cellulases. In this work, cellulase (NS50013) and β-glucosidase (Novozyme 188) were immobilized on enzymogels made of poly(acrylic acid) polymer brushes grafted to the surface of silica nanoparticles. Response surface methodology was used to model effects of pH and temperature on hydrolysis and recovery of free and attached enzymes. Hydrolysis yields using both enzymogels and free cellulase and β-glucosidase were highest at the maximum temperature tested, 50 °C. The optimal pH for cellulase enzymogels and free enzyme was 5.0 and 4.4, respectively, while both free β-glucosidase and enzymogels had an optimal pH near 4.4. Highest hydrolysis sugar concentrations with cellulase and β-glucosidase enzymogels were 69 and 53 % of those with free enzymes, respectively. Enzyme recovery using enzymogels decreased with increasing pH, but cellulase recovery remained greater than 88 % throughout the operating range of pH values less than 5.0 and was greater than 95 % at pH values below 4.3. Recovery of β-glucosidase enzymogels was not affected by temperature and had little impact on cellulase recovery.

A new approach to the crosslinking and filling synthetic latex coatings has been developed. Peroxidized monodisperse polystyrene latex particles have been used as a crosslinker and, simultaneously, as a filler of polymer coatings based on acrylic and styrene-butadiene latexes. The synthesis of reactive (peroxidized) latex particles was carried out using the emulsion polymerization of styrene in the presence of the polymer inisurf, the initiator-surfactant, a copolymer of a peroxide monomer, N-[(tert-butylperoxy)methyl]acrylamide with maleic anhydride. The reactive latex particles were employed to crosslink polymer coatings from synthetic acrylic and styrene-butadiene latexes. The hardness and solvent resistance of the coatings based on both latexes increase with an increasing amount of the reactive latex filler in the formulation. The crosslinked coatings, based on styrene-butadiene exhibited better characteristics in terms of hardness and solvent stability. The properties of latex-crosslinked coatings depend on reaction temperature and the amount of the crosslinker, peroxidized reactive polystyrene latex particles.

The enzymogel has revealed unique properties making it a novel type of phase-boundary biocatalyst. This chapter discusses the application of cellulase (CEL) enzymes to cleave cellulose chains and transform them to glucose which could be used for the production of biofuels or biochemicals. A multicycle hydrolysis of cellulose could be realized using both mechanisms of enzymogel bioactivity: multiple release and uptake of CEL by recyclable enzymogel or multiple use of the enzymogel with no release of CEL. One of unique and interesting aspect of enzymogel particles is related to magnetic field directed bioconversion process. High enzyme loadings make the use of nanoparticles more efficacious as long as a biocatalytic activity of the enzyme does not decrease significantly at increased loadings. The concentrations of glucose and total reducing carbohydrates after partial biocatalytic cleavage of cellulose with free enzymes and enzymogel nanoparticles were monitored to reveal the impact of pH and temperature.