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This study demonstrated that polymerization behavior of plant oil-based acrylic monomers (POBMs) synthesized in one-step transesterification reaction from naturally rich in oleic acid olive, canola, and high-oleic soybean oils is associated with a varying mass fraction of polyunsaturated fatty acid fragments (linoleic (C18:2) and linolenic (C18:3) acid esters) in plant oil. Using miniemulsion polymerization, a range of stable copolymer latexes was synthesized from 60 wt.% of each POBM and styrene to determine the impact of POBM chemical composition (polyunsaturation) on thermal and mechanical properties of the resulted polymeric materials. The unique composition of each plant oil serves as an experimental tool to determine the effect of polyunsaturated fatty acid fragments on POBM polymerization behavior and thermomechanical properties of crosslinked films made from POBM-based latexes. The obtained results show that increasing polyunsaturation in the copolymers results in an enhanced crosslink density of the latex polymer network which essentially impacts the mechanical properties of the films (both Young's modulus and toughness). Maximum toughness was observed for crosslinked latex films made from 50 wt.% of each POBM in the monomer feed.

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 (C 15 -C 17 ) 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.

Influenza A viruses (IAVs) are a group of genetically diverse and economically important zoonotic pathogens. Despite decades of research, effective and broadly protective vaccines are yet to be developed. Recent breakthroughs in epitope-based immunization for influenza viruses identify certain conserved regions of the HA2 and M2e proteins as capable of inducing broad protection against multiple influenza strains. The M2e and HA2 peptides have been evaluated in mice but not as a combination in pigs, which play an important role in the transmission and evolution of IAV. Peptides are inherently weak immunogens; and effective delivery of peptide antigens is challenging. To enhance the delivery and immunogenicity of peptide-based vaccines, the conserved M2e and HA2 and a strain-specific HA1 epitope of Influenza A (H1N1) pdm09 were expressed as a chain in a bacterial expression system and entrapped in a novel amphiphilic invertible polymer made from polyethyelene glycol (PEG, molecular weight 600 g/mol) and polytetrahydrofuran (PTHF, molecular weight 650 g/mol), PEG 600 PTHF 650 . Piglets vaccinated with polymeric peptide vaccine mounted significantly stronger antibody responses against the peptide construct when compared to piglets immunized with the multi-epitope peptide alone. When vaccinated pigs were challenged with Influenza A (H1N1) pdm09, viral shedding in nasal secretions and lung lesion scores were significantly reduced when compared to the unvaccinated controls and pigs vaccinated with the peptide alone at six days post-challenge. Thus, the combination of the PEG 600 PTHF 650 polymer and trimeric peptide construct enhanced delivery of the peptide antigen, acted as an adjuvant in stimulating strong antibody responses, reduced the effects of viral infection in vaccinated pigs., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

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. PEG 600 -PTHF 650 , 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 PEG 600 -PTHF 650 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., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Strategically designed amphiphilic invertible polymers (AIPs) are capable of (i) self-assembling into invertible micellar assemblies (IMAs) in response to changes in polarity of environment, polymer concentration, and structure, (ii) accommodating (solubilizing) substances that are otherwise insoluble in water, and (iii) inverting their molecular conformation in response to changes in the polarity of the local environment. The unique ability of AIPs to invert the molecular conformation depending on the polarity of the environment can be a decisive factor in establishing the novel stimuli-responsive mechanism of solubilized drug release that is induced just in response to a change in the polarity of the environment. The IMA capability to solubilize lipophilic drugs and deliver and release the cargo molecules by conformational inversion of polymer macromolecules in response to a change of the polarity of the environment was demonstrated by loading IMA with a phytochemical drug, curcumin. It was demonstrated that four sets of micellar vehicles based on different AIPs were capable of delivering the curcumin from water to an organic medium (1-octanol) by means of unique mechanism: AIP conformational inversion in response to changing polarity from polar to nonpolar. The IMAs are shown to be nontoxic against human cells up to a concentration of 10 mg/L. On the other hand, the curcumin-loaded IMAs are cytotoxic to breast carcinoma cells at this concentration, which confirms the potential of IMA-based vehicles in controlled delivery of poorly water-soluble drug candidates and release by means of this novel stimuli-responsive mechanism.

'Host-guest' interactions between self-assembled micellar nanostructures from amphiphilic invertible polymers (AIPs) and two peptides, swine-origin Influenza A surface protein Hemagglutinin and research antibody peptide V5, are investigated by changing the polymer concentration and polymer/peptide ratio in the aqueous solution. Formation of mixed micellar assemblies from AIP and each peptide is revealed using detailed 1H NMR spectroscopic study. Peptide molecule localization in the micellar assemblies depends on the specific interactions between amino acid functional groups of the peptide and polymer fragments. The resulting mixed micellar structures can be considered as a promising material toward delivery and stimuli-responsive sustained release of peptides. [ABSTRACT FROM AUTHOR]

Systematic review of experimental and clinical data on the use of curcumin in the treatment of osteosarcoma is presented. The current status of curcumin’s therapeutic potential against bone cancer is analyzed in regard to using polymeric micelles (including recently developed invertible, responsive, micelles) as a platform for curcumin delivery to treat osteosarcoma. The potential of micellar assemblies from responsive macromolecules in a controlled delivery of curcumin to osteosarcoma cells, and the release using a new inversion mechanism is revealed. [ABSTRACT FROM AUTHOR]

The enzymogel nanoparticle made of a magnetic core and polymer brush shell demonstrates a novel type of remote controlled phase-boundary biocatalysis that involves remotely directed binding to and engulfing insoluble substrates, high mobility, and stability of the catalytic centers. The mobile enzymes reside in the polymer brush scaffold and shuttle between the enzymogel interior and surface of the engulfed substrate in the bioconversion process. Biocatalytic activity of the mobile enzymes is preserved in the enzymogel while the brush-like architecture favors the efficient interfacial interaction when the enzymogel spreads over the substrate and extends substantially the reaction area as compared with rigid particles. [ABSTRACT FROM AUTHOR]

The article discusses a study which synthesized porous polyacrylamide (PAAm) hydrogels with improved mechanical properties and regular pore distribution. It notes that leaching out of chemically modified silica particles was used to form hydrogel pores. Results of the study showed that the dispersibility of the porogen material in the hydrogel composition was improved by the grafted PAAM layer on the silica surface. It cites the steps involved in developing porous hydrogels.

Abstract: A universal technique is developed to coat uniform layer of catalyst on any targeted substrate. The technique is based on a novel concept of catalyst deposition by using polymer–metal complexes in the form of invertible polymeric nanostructures through molecular self-assembly. Growth of carbon nanofibres on carbon microfibres was demonstrated to show this technique. [Copyright &y& Elsevier]

A functionalization of iron oxide nanoparticles (NPs) of different diameters by the amphiphilic invertible polymer, (PEG600‐alt‐PTHF650)k (PEG and PTHF stand for poly(ethylene glycol) and poly(tetrahydrofuran), respectively), leads to different NP/polymer architectures for dye/drug uptake and release, as is reported here for the first time. It is demonstrated that 18.6 ± 1.4 and 11.9 ± 0.6 nm NPs are individually coated by this polymer, while 5.9 ± 0.6 nm NPs form nanoparticle clusters (NPCs) which could be isolated by either ultracentrifugation or magnetic separation. This phenomenon is most likely due to the character of the (PEG600‐alt‐PTHF650)k macromolecule with alternating hydrophilic and hydrophobic fragments and its dimensions sufficient to cause NP clustering. Utilizing Rhodamine B base (RBB) and doxorubicin (DOX), the data on uptake upon mixing and further release via inversion into octanol (mimicking the penetration of the cell biomembrane) are presented. The magnetic NPCs display enhanced uptake and release of both RBB and DOX most likely due to the higher retained polymer amount. The NPCs also display exceptional magnetic resonance imaging properties. This and the high uptake/release efficiency of the NPCs combined with easy magnetic separation make them promising for theranostic probes for magnetically targeted drug delivery. [ABSTRACT FROM AUTHOR]

Semibatch emulsion polymerization of high oleic soybean oil-based monomer (HO-SBM), 2–ethylhexyl acrylate (2-EHA), and styrene (St) was applied to synthesize pressure-sensitive latex adhesives with up to 40 wt% of plant oil-based content. Ternary latex copolymers with similar chemical composition and broadly different molecular weight distribution (MWD) and modality were synthesized at varying temperatures and the mechanism of free-radical initiation. Conventional thermal initiation with ammonium persulphate at 80 °C and ascorbic acid/ tert -butyl hydroperoxide redox system of lower reaction temperature up to 20 °C were employed. Linear, short-chain, and long-chain branched macromolecules are formed due to chain-breaking reactions of HO-SBM (chain transfer on allyl groups) and 2-EHA (inter- and intramolecular chain transfer on the polymer). The dominant effect of chain transfer on allyl group protons and subsequent decrease in molecular weight was observed at higher reaction temperatures, while extensively branched polymer with high molecular weight was obtained at reaction temperature close to 20 °C. The effect of MWD and branching on the PSAs performance of synthesized biobased latexes was studied using loop tack and peel strength and lap shear testing and compared to two commercial PSA tapes as a benchmark. A significant increase in shear strength (up to 0.23 MPa) was observed for latex adhesives due to high molecular weight fractions, maintaining satisfactory level of tack (3–7 N) and peel (3–6 N/in). Broad MWD of the copolymers can be beneficial for providing materials with high shear strength (0.25–0.33 MPA) while preserving the significant level of tack (2–4 N) and peel strength (9–12 N/in) on both glass and steel substrates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Vanillin-derived aromatic vinyl monomers undergo chain addition polymerization. • Biobased styrenes can be combined in copolymerization as conventional vinyl monomers. • Biobased aromatic vinyl monomers can act as "rigid" fragments in thermoset coatings. • Propagation coexists with intermolecular transfer to poly(3-allyl-5-vinylveratrole) Chemical structure (effect of functional substituents on vinyl bond reactivity) was used as a criterion to evaluate the (co)polymerization behavior of vanillin-derived 3-allyl-5-vinylveratrole, 4-vinylveratrole, and 2-glycidoxy-5-vinylanisole in chain-growth polymerization mechanism. After polymerization, allyl and epoxy functional groups of monomer units remain unaffected as macromolecular side groups and can be utilized in post-polymerization reactions (in particular, cross-linking). Due to the intermolecular chain transfer to polymer, a fraction of branched macromolecules can be formed in free radical polymerization of 3-allyl-5-vinylveratrole. At the same time, the kinetic study shows a similar polymerization rate for all the three investigated biobased aromatic vinyl monomers. Determined in copolymerization with methyl methacrylate Q-e values indicate that 3-allyl-5-vinylveratrole, 4-vinylveratrole and 2-glycidoxy-5-vinylanisole behave like conventional vinyl monomers and can be copolymerized interchangeably. In this manner, macromolecules with controlled amounts of cross-linkable epoxy and allyl groups incorporated into the backbone can be synthesized. Based on the glass transition temperature of the homopolymers thereof (66–93 °C), biobased aromatic vinyl monomers can serve as "rigid" macromolecular fragments and be applied in the formulation of thermoset polymer coatings. Being derived from renewable resources, 3-allyl-5-vinylveratrole, 4-vinylveratrole, and 2-glycidoxy-5-vinylanisole can be considered as a replacement for petroleum-based commodity styrene in the production of various industrial polymeric materials that utilize aromatic monomers. [ABSTRACT FROM AUTHOR]

Amphiphilicinvertible polymers (AIPs) are a new class of macromoleculesthat self-assemble into micellar structures and rapidly change structurein response to changes in solvent polarity. Using small-angle neutronscattering (SANS) data, we obtained a quantitative description ofthe invertible micellar assemblies (IMAs). The detailed compositionand size of the assemblies (including the effect of temperature) weremeasured in aqueous and toluene polymer solutions. The results showthat the invertible macromolecules self-assemble into cylindricalcore–shell micellar structures. The composition of the IMAsin aqueous and toluene solutions was used to reveal the inversionmechanism by changing the polarity of the medium. Our experimentsdemonstrate that AIP unimers self-assemble into IMAs in aqueous solution,predominantly through interactions between the hydrophobic moietiesof macromolecules. The hydrophobic effect (or solvophobic interaction)is the major driving force for self-assembly. When the polarity ofthe environment is changed from polar to nonpolar, poly(ethylene glycol)(PEG) and aliphatic dicarboxylic acid fragments of AIP macromoleculestend to replace each other in the core and the shell of the IMAs.However, neither the interior nor the exterior of the IMAs consistsof fragments of a single component of the macromolecule. In aqueoussolution, with the temperature increasing from 15 to 35 °C, theIMAs’ mixed core from aliphatic dicarboxylic acid and PEG moietiesand PEG-based shell change the structure. As a result of the progressivedehydration of the macromolecules, the hydration level (water content)in the micellar core decreases at 25 °C, followed by dehydratedPEG fragments entering the interior of the IMAs when the temperatureincreases to 35 °C. [ABSTRACT FROM AUTHOR]