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Vinyl group capped urethane acrylate (UA) was prepared with diisocyanate (IPDI), hydroxyethyl methacrylate (HEMA) and dimethylolpropionic acid (DMPA). The UA was grafted onto sodium alginate via free-radical polymerization with KPS/Na2SO3 as initiator and then crosslinked by Ca(2+). Grafted polymers (UA-g-CaA) were characterized by FT-IR, SEM, TGA, XRD and tension gauge. The swelling behavior was also investigated. It is found that urethane acrylate grafted calcium alginate possesses lower swelling degree and is improved in thermal stability as well as mechanical performance. The reason is that hydrophobic urethane acrylate provides alginate with physical crosslinking and forms partial crystal regions. The optimum condition for synthesis of UA-g-CaA with lower swelling degree is that weight percentage of initiator to monomer is 0.8%, mass ratio of reductant to oxidant is 0.45:1, monomer concentration is 0.0385mol/L and grafting reaction temperature is 55°C., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Oil pollution from the petroleum industry is a growing problem, especially in terms of the harm it causes to the aquatic environment, which puts humans and other aquatic life in grave danger. As immobilized carriers for the removal of diesel, thermoplastic polyurethane (TPU) nanofiber membranes and co-blended nano-hydroxyapatite modified thermoplastic polyurethane (TPU/nHA) nanofiber membranes are reasonably priced, non-toxic, and non-polluting. The adhesion and colonization of the bacterial cells to these carriers were studied using scanning electron microscopy (SEM). Gas chromatography was used to measure the bioremediation effectiveness, and the results after 3 days of remediation revealed a substantial improvement in the removal of hydrocarbons by immobilization compared to free bacteria. With an initial concentration of 3 g/L diesel, the TPU/1.5HA-bacteria system enhanced the removal of diesel the most (20.64 ± 0.40%), followed by TPU/1HA-bacteria (17.49 ± 0.08%), TPU/0.5HA-bacteria (11.97 ± 0.40%), and TPU-bacteria (4.69 ± 0.13%), in that order. Within three days, these scaffolders had completely absorbed the spilled diesel. There haven't been any studies done yet on the removal of diesel using various carriers loaded with Bacillus altitudinis LS-1. This study demonstrated that TPU-based electrostatic spinning films can be used as bio-carriers for hydrocarbon-degrading bacteria, enhancing the bioremediation of oil-contaminated water. [ABSTRACT FROM AUTHOR]

ABSTRACT Protein-imprinted polyurethane-grafted calcium alginate hydrogel microspheres were prepared and characterized. The samples were investigated with optical microscopy, scanning electron microscopy, 13C-NMR, and Fourier transform infrared spectroscopy. We proved that polyurethane side chains were successfully grafted, and this led to a relatively rough and dense surface. The samples exhibited better swelling durability when applied in specific adsorption tests. The adsorption kinetic and recognition properties indicated that the imprinted modified microspheres had excellent rebinding affinity toward the target proteins. Moreover, the influence of the preassembly pH, rebinding pH, and grafting ratio on the adsorption capacity and imprinting efficiency (IE) were systematically investigated. The study results suggest that the modified samples possessed a higher IE toward the target protein under the optimum pH and grafting ratio. Upon polyurethane grafting modification, the alginate hydrogel microspheres showed improved mechanical stability and recognition specificity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42140. [ABSTRACT FROM AUTHOR]

Polyurethane grafted calcium alginate hydrogel microspheres intended for bovine serum albumin imprinting were prepared and characterized. The grafting modification was performed prior to the assembling of protein template with hydrogel, which was advantageous to maintain protein conformation and construct more accessible imprinted sites. It was found that the imprinted hydrogel had higher affinity to template molecules after modification. Investigations of grafting ratio influence on specific rebinding and competitive properties indicated that grafted side chains were beneficial to the selective recognition of protein. [ABSTRACT FROM AUTHOR]

Abstract: Polyurethane was synthesized by the reaction of isophorone diisocyanate, 2-hydroxyethyl methacrylate and diethylene glycol. Then polyurethane grafted calcium alginate gel material was prepared via free-radical grafting polymerization with azobisisobutyronitrile as an initiator. Modified calcium alginate hydrogel was improved in thermal property, crystallinity and anti-swelling properties. The reason is that polyurethane side chains affect the arrangement of calcium alginate by forming highly ordered crystal region. [Copyright &y& Elsevier]

Sodium lignosulfonate amine (SLA) was synthesized by Mannich reaction. The lignin-modified waterborne polyurethane (WPU) with different branched structures was designed and prepared by introducing SLA as a hydrophilic chain extender. The effect of the introduction manner of SLA on the performance of WPU was systematically investigated. The results showed that the addition of 0.75 wt% SLA in an appropriate introduction manner can prepare a polyurethane dispersion with good stability and high solid content. The tensile strength of the SLA-modified WPU film was significantly improved to 37.3 MPa. The SLA-modified WPU film also exhibited high water resistance and thermal stability. Moreover, in the introduction manner of WPU-C, the adhesive properties of SLA-modified WPU adhesives were also improved, which was mainly attributed to the entanglement of long branched chains generated by SLA chain extension with other polyurethane chains and the formation of physically cross-linked networks through the interaction between functional groups. Therefore, the introduction of a small amount of sodium lignosulfonate amine in an appropriate manner can significantly improve the performance of WPU with high solid content, which provides a new way to prepare high-performance waterborne polyurethane. [Display omitted] • Sodium lignosulfonate amine optimized the structure of waterborne polyurethane. • A small amount of sodium lignosulfonate amine improved the properties of WPU. • Provide a new idea for preparation of high-performance WPU. • Expand the way for high-value utilization of sodium lignosulfonate. [ABSTRACT FROM AUTHOR]