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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]

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]

(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. Image 1 • An integrated process of soybean oil-based monomers was designed and simulated. • TEA shows a competitive minimum selling price of $78.4/kg in the base case. • Renewable content of the specialty chemical is a key technical parameter for cost. • Carbon abatement shows the low carbon option is cheaper than business-as-usual. • Uncertainties in the price of the fossil-based component has the major impact. [ABSTRACT FROM AUTHOR]

• Monomers from plant oils copolymerized with water soluble counterparts in emulsion. • Resulted latex particle formation occurs by both micellar and homogeneous mechanism. • Emulsion copolymerization loci change when hydrophobicity of feed increases. • Aqueous solubility of POBM counterpart determines particle formation mechanism. • POBM presence is kinetically irrelevant if reactivity of counterpart radicals is high. 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. [ABSTRACT FROM AUTHOR]

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. [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]

Abstract: Continued development of up-to-date polymer composite materials demands the design of certain interfacial layers in composite structure. The aim of this paper was to review recent advances in the synthesis of reactive polymeric surfactants (RPSs) and the application of 14 different RPSs for the modification of the interface in aqueous dispersions of polymers, reinforced polymer-based composites, and polymer blends. The activation (peroxidation) of planar polymer surfaces with RPSs for their further modification in order to impart specific surface properties was discussed as well. In the paper method of compatibilization of the blends of thermodynamically immiscible polymers through the formation in situ of a universal compatibilizer based on RPS was introduced. Finally, the features of the RPS macromolecules' adsorption on the surface of latex particles, inorganic filler particles, and planar polymer surfaces along with the formation of adsorbed reactive polymer layers are discussed. [Copyright &y& Elsevier]