Diethylamino Ethyl Methacrylate Research Articles

Construction and degradation mechanism of polylactic acid-pH-responsive microgel composite system plugging system

Polylactic acid (PLA) is often used as a degradable temporary plugging agent for bridging plugging, but its particles are rigid, resulting in lax plugging. Based on the acidic properties of the polylactic acid (PLA) degradation solution, pH-responsive microgels were used as flexible filler particles to construct a completely degradable polylactic acid (PLA)-pH-responsive microgel composite temporary plugging system. Using diethylaminoethyl methacrylate (DEAEMA) and acrylamide (AM) as functional monomers, pH-responsive flexible microgel particles were prepared by soap-free emulsion polymerization. The microgels were characterized by FT-IR, SEM, particle size distribution, Zeta potential, electrical conductivity, and surface tension at different pH conditions. The results showed that microgel particles could be completely dissolved in acidic environment. Furthermore, the plugging experiment showed that the plugging rate of the polylactic acid-microgel system reached more than 99%, which was 5.91% higher than that of polylactic acid particles. The addition of pH-responsive microgel could catalyze the degradation of polylactic acid, and the degradation speed was accelerated with the increase of the dosage. Meanwhile, the microgel was completely dissolved by the degradation solution of polylactic acid, forming a clear and transparent solution. Finally, the synergistic degradation mechanism of the polylactic acid-pH-responsive microgel composite system plugging agent system was summarized. This system provides a new idea for the design of a temporary plugging agent and has a broad application prospect in acid fracturing.

Hydrophilic macroporous monoliths with tunable water uptake capacity fabricated by water‐in‐oil high internal phase emulsion templating

AbstractIn this contribution, a series of well‐defined amphiphilic di‐block copolymers poly(ethylene oxide)‐b‐polystyrene (PEO43‐b‐PSx) with different PS segment lengths of x = 41, 78, and 130 units were synthesized through activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). The as‐prepared block copolymers successfully stabilized the water‐in‐oil (W/O) high internal phase emulsions (HIPEs) containing pH responsive monomers 2‐(dimethylamino)ethyl methacrylate (DMAEMA) and 2‐(diethylamino)ethyl methacrylate (DEAEMA). The effect of macro‐surfactant loading, PS segment length, and DMAEMA/DEAEMA content on the stability of HIPEs and the corresponding polyHIPE structure were investigated. Results show that the average void size of polyHIPE decreases with the increase of surfactant concentration. Macroporous morphologies with closed‐cell or open‐cell can be manipulated by surfactant loading as well. The openness of polyHIPE decreases as the increase in hydrophobic PS segment length. Compared to DMAEMA containing HIPE systems, stable DEAEMA containing HIPEs are more easily obtained by using the as‐prepared macro‐surfactant. Stable HIPE with a relatively large amount of DEAEMA, up to 70 vol% of oil‐phase has been achieved. The obtained PDEAEMA‐co‐PS polyHIPEs derived from 0.116 mol% PEO43‐b‐PS41 stabilized emulsion templates show pH responsiveness towards water absorption and the highest acidic water uptake capacity can be up to 6.6 times its weight at equilibrium state. This work paves the way for the preparation of hydrophilic macroporous monolith from stable W/O HIPE template, and confirms the strength of macro‐surfactant in such an approach.

Smart Nanocarrier Based on Poly(oligo(ethylene glycol) methyl ether acrylate) Terminated pH-Responsive Polymer Brushes Grafted Mesoporous Silica Nanoparticles

A platform technology based on inorganic/organic nanoparticles for carrying drugs could be of enormous potential benefit in treating cancer. Surface modification of the nanoparticles with pH-responsive and biocompatible polymers can improve the selectivity and targeting toward the tumor cells. Polyethylene glycol (PEG) and its derivatives being present on the surface could enhance the ability to tailor nanomaterial hydrophilicity and to resist the adhesion of proteins and/or cells. Herein, we report a new nanoplatform based on mesoporous silica nanoparticles (MSNs) conjugated with poly(2-(diethylamino) ethyl methacrylate) (PDEAEMA) brushes as a candidate for stimuli-responsive intracellular drug delivery system. Alkyl bromide functional initiators (end-functionalized PDEAEMA brushes) were derivatized to amine, followed by the reaction with ethylene sulfide and poly(oligo(ethylene glycol) methyl ether acrylate (POEGMEA). Using X-ray photoelectron spectroscopy (XPS) to examine the attachment of POEGMEA, it was found that the POEGMEA molecules in the outer surface of PDEAEMA brushes have been successfully reacted with thiol groups, as indicated by the increase in the peak intensity of the C–O group at 286.5 eV. Brush-modified silica hybrids have an average diameter of ca. 250 nm, as estimated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Rhodamine B dye was loaded into the brush-modified silica hybrids nanoparticles with loading capacity of ca. 74%. The accumulated dye released from brush-modified particles in acidic media was approximately 60%, whereas the dye amount release in basic media was less than 15% after 10 h exposure time. Alamar Blue assay was used to assess the cytotoxicity of MSNs–PDEAEMA, MSNs–PDEAEMA–SH, and MSNs–PDEAEMA–POEGMEA. The results show that all three nanosystems were non-toxic to hMSC with an increase in cell proliferation for MSNs–PDEAEMA–POEGMEA at 50 µg/mL after both 24 and 48 h of incubation.

Structural Exploration of Polycationic Nanoparticles for siRNA Delivery.

RNA interference (RNAi) is a promising approach to the treatment of genetic diseases by the specific knockdown of target genes. Functional polymers are potential vehicles for the effective delivery of vulnerable small interfering RNA (siRNA), which is required for the broad application of RNAi-based therapeutics. The development of methods for the facile modulation of chemical structures of polymeric carriers and an elucidation of detailed delivery mechanisms remain important areas of research. In this paper, we synthesized a series of methacrylate-based polymers with controllable structures and narrow distributions by atom transfer radical polymerization using various combinations of cationic monomers (2-dimethylaminoethyl methacrylate, 2-diethylaminoethyl methacrylate, and 2-dibutylaminoethyl methacrylate) and hydrophobic monomers (2-butyl methacrylate (BMA), cyclohexyl methacrylate, and 2-ethylhexyl methacrylate). These polymers exhibited varying hydrophobicities, charge densities, and pKa values, enabling the discovery of effective carriers for siRNA by in vitro delivery assays. For the polymers with BMA segments, 50% of cationic segments were beneficial to the formation of siRNA nanoparticles (NPs) and the in vitro delivery of siRNA. The optimal ratio varied for different combinations of cationic and hydrophobic segments. In particular, 20k PMB 0.5, PME 0.5, and PEB 1.0 showed >75% luciferase knockdown. Efficacious delivery was dependent on high siRNA binding, the small size of NPs, and balanced hydrophobicity and charge density. Cellular uptake and endosomal escape experiments indicated that carboxybetaine modification of 20k PMB 0.5 did not remarkably affect the internalization of corresponding NPs after incubation for 6 h but significantly reduced the endosomal escape of NPs, which leads to the notable decrease in delivery efficacy of polymers. These results provide insights into the mechanism of polymer-based siRNA delivery and may inspire the development of novel polymeric carriers.

Synthesis, monomer reactivity ratios and antibacterial activity of 2-hydroxy ethyl methacrylate and 2-(Diethylamino) ethyl methacrylate copolymers

Synthesis, monomer reactivity ratios and antibacterial activity of 2-hydroxy ethyl methacrylate and 2-(Diethylamino) ethyl methacrylate copolymers

Functional plasma-polymerized hydrogel coatings for electrochemical biosensing

Acrylate-based hydrogels with multifunctional properties have proven to be suitable candidates for the development of sensor systems. They gained popularity especially in combination with bioelectronics, as there is a need to understand and control the interactions of bionic devices with the human body and other environments. In this study, we present results on the biointeraction capability of plasma-polymerized (pp) hydrogels made of hydroxyethyl methacrylate (HEMA) and 2-(diethylamino)ethyl methacrylate (DEAEMA) mixtures on gold screen-printed electrodes (SPE). The hydrogels were generated by an atmospheric pressure plasma jet, and their chemical composition was characterized via FT-IR. The FT-IR analysis revealed several functional groups suitable for biomolecule immobilization, whereas the amount of -C-N, –OH, and -C-O-C groups differs depending on the mixture ratios. The pp HEMA:DEAEMA (HD) hydrogel coatings provide alternative interfacing materials for electrochemical biosensing. The enzymes glucose oxidase (GOx) and acetylcholinesterase (AChE) were coupled to the hydrogel-based surfaces, and the effects of the mixture ratios on the biomolecule immobilization were investigated. It is possible to address different functional groups of the mixtures with different immobilization strategies; thus, the sensor response can be optimized. Finally, glucose as GOx substrate and eserine as AChE inhibitor were detected by amperometry to demonstrate the practical biosensing applicability of the coatings.

Synthesis and characterisation of a novel pH-sensitive flocculant and its flocculation performance

In this study, a novel pH-sensitive flocculant, poly(AM-DEA-DPL) (PADD), was synthesised using acrylamide (AM), diethylaminoethyl methacrylate (DEA), and dodecyl glucoside (DPL) as monomers through solution copolymerisation. The synthesis conditions were optimised, and the intrinsic viscosity and conversion rate of the polymer were improved. The molecular structure of the flocculant was determined through Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopy analysis. The isoelectric points of PADD were found to be pH 4 through zeta potential measurements, indicating that PADD is an amphoteric flocculant. The change in turbidity with pH reflected the pH sensitivity and the change in the hydrophilicity and hydrophobicity of the polymer. Gel permeation chromatography (GPC) measurements showed that the average molecular weight of the polymer was 89,310. PADD had great turbidity removal and flocculation effects on both hydrophilic kaolin and hydrophobic molybdenite. At pH 2–8, a small amount of flocculant had excellent flocculation effects on kaolin and molybdenite suspensions. According to FTIR characterisation and zeta potential measurements of the flocs, and to previous reports, this was mainly the result of electrostatic attraction, adsorption bridging, hydrophobic association, and synergy. The PADD flocculant has promising industrial applications.

Acid-base responsive photoluminescence switching of CdSe/ZnS quantum dots coupled to plasmonic gold film using nanometer-thick poly[(2-diethylamino)ethyl methacrylate] layer.

The control of plasmon-nanoemitter interactions at the nanoscale enables the tailored modulation of optical properties, namely, the photoluminescence (PL) intensity of the nanoemitters. In this contribution, using a nanometer-thick poly[(2-diethylamino) ethyl methacrylate] (39 to 74 nm) as pH responsive spacer layer (pKa ∼ 6 to 6.5) between a plasmonic gold film and CdSe/ZnS Quantum Dots (QDs) nanoemitters, we could achieve reversible pH-responsive PLswitching in QDs. In fact, the swelling (at pH 5) and shrinking (at pH 11) function of the pH-responsive spacer layer modulates the distance between the QDs and the gold surface, which dictates the plasmonic film-QDs nanoemitter interaction. Notably, we observed a high QDs' PL enhancement of up to a factor of 3.1 ± 0.4 through changing the pH value from 5 to 11. Furthermore, based on a systematic analysis of several samples with different spacer layer thicknesses and multiple pH cycles, our developed system revealed substantial stability, reversibility and PL enhancement reproducibility. Thus, the established acid-base responsive switchable systems may represent an appealing platform for applications such as sensors, biochemical assays, optoelectronics and logic gates and can be easily evolved to other multifunctional switchable systems using alternative stimuli-responsive polymers.

In situ preparation of glyco-micromotors and their bacteria loading/guiding ability.

We successfully synthesized glyco-micromotors in situ directed by multifunctional glycopolymers, which were obtained by copolymerizing 2-methacrylamido glucopyranose (MAG) and 2-(diethylamino)ethyl methacrylate (DEAEMA) monomers. The fabricated glyco-micromotors present abilities in loading and guiding bacteria with different individual and group motions.

Preparation of Developing Biotinylated PH-Responsive Glycopolymers as Delivery Nanocarriers for Controlling Release of Bortezomib

To develop biotinylated pH-responsive glycopolymers and investigate their performances as anticancer drug delivery nanocarriers, bromide-terminated biotin was synthesized and then used to initiate the polymerization of D-gluconamido ethyl methacrylate (GAMA) and 2-(diethylamino)ethyl methacrylate (DEA) monomers via atom transfer radical polymerization (ATRP). Two biotinylated pH-responsive copolymers with similar degree polymerization (DP) chain segments, Biotin-P(GAMA-b-DEA) and Biotin-P(GAMA-co-DEA), were prepared by block or random architectures, respectively. The chemical compositions and self-assembly behavior of glycopolymers were characterized. The results show that the block glycopolymer self-assembles in water medium into core-shell structure assembly containing PGAMA shell and PDEA core with the 28 nm in diameter, while the random glycopolymer remains water-soluble state above pH 7.4. Both glycopolymers possess the loading ability of the BTZ with encapsulation efficiency (EE %) and loading capacity (LC %) of 83.7% and 8.4%, 78.7% and 7.9%, and the release behavior was kept at low constants with 20% and 26% cumulative amount even after 24 hours at pH 7.4, respectively. The study is expected to give the light to the development of new intelligent drug carrier system with excellent biological compatibility.

Quantifying the Endosomal Escape of pH-Responsive Nanoparticles Using the Split Luciferase Endosomal Escape Quantification Assay

All nanoparticles have the potential to revolutionize the delivery of therapeutic cargo such as peptides, proteins, and RNA. However, effective cytosolic delivery of cargo from nanoparticles represents a significant challenge in the design of more efficient drug delivery vehicles. Recently, research has centered on designing nanoparticles with the capacity to escape endosomes by responding to biological stimuli such as changes in pH, which occur when nanoparticles are internalized into the endo-/lysosomal pathway. Current endosomal escape assays rely on indirect measurements and yield little quantitative information, which hinders the design of more efficient drug delivery vehicles. Therefore, we adapted the highly sensitive split luciferase endosomal escape quantification (SLEEQ) assay to better understand nanoparticle-induced endosomal escape. We applied SLEEQ to evaluate the endosomal escape behavior of two pH-responsive nanoparticles: the first with a poly(2-diisopropylamino ethyl methacrylate) (PDPAEMA) core and the second with 1:1 ratio of poly(2-diethylamino ethyl methacrylate) (PDEAEMA) and PDPAEMA. SLEEQ directly measured the cytosolic delivery and showed that engineering the nanoparticle disassembly pH could improve the endosomal escape efficiency by fivefold. SLEEQ is a versatile assay that can be used for a wide range of nanomaterials and will improve the development of drug delivery vehicles in the future.

A CO2-stimulus responsive PVDF/PVDF-g-PDEAEMA blend membrane capable of cleaning protein foulants by alternate aeration of N2/CO2

• A CO 2 -responsive PVDF/PVDF-g-PDEAEMA blend membrane was fabricated. • The blend membrane exhibits a switchable water flux by alternate aeration of N 2 /CO 2. • The protein fouling can be efficiently removed by alternate aeration of N 2 /CO 2. • Flux recovery of membrane by this method is fairly satisfactory. • Switchable hydrophobic/hydrophilic transition is responsible for membrane cleaning. In this work, a novel CO 2 -stimulus responsive copolymer polyvinylidene fluoride-graft- (2-diethylaminoethyl methacrylate) (PVDF-g-PDEAEMA) was synthesized by a free-radical copolymerization method, and then PVDF/PVDF-g-PDEAEMA blend membrane was fabricated, with a switchable pure water flux by alternate aeration (N 2 /CO 2 ). The water flux of the blend membrane under the pressure of CO 2 is significantly lower than that under N 2 pressure, indicating the CO 2 -responsive property of the membrane, which is due to the protonation or deprotonation reaction of tertiary amine groups in PDEAEMA. After CO 2 aeration, the PDEAEMA segments within pores of the membrane are extended due to the protonation reaction, which results in the shrinkage of membrane pores, thereby decreasing the water flux of the membrane. Taking advantage of the CO 2 -stimulus responsiveness, the alternate aeration (N 2 /CO 2 ) method is adopted to clean protein on the blend membrane surface without the introduction of chemical reagents. The flux recovery rate of the blend membrane cleaned by this green method is fairly satisfactory (89.9%), which is comparable to the results of acid cleaning (90.6%) and alkaline cleaning (95.2%). The switchable hydrophilic/hydrophobic transition on membrane surfaces upon alternating exposure of CO 2 /N 2 , is mainly responsible for membrane cleaning.

Oxygen-Tolerant RAFT Polymerization Catalyzed by a Recyclable Biomimetic Mineralization Enhanced Biological Cascade System.

An enzyme cascade system including glucose oxidase (GOx) and iron porphyrin (DhHP-6) is encapsulated in a metal-organic framework called zeolitic imidazolate framework-8 (ZIF-8) through one-step facile synthesis. The composite (GOx&DhHP-6@ZIF-8) is then used to initiate oxygen-tolerant reversible addition-fragmentation chain-transfer polymerization for different methacrylate monomers, such as 2-diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate, and poly(ethylene glycol) methyl ether methacrylate (Mn = 500g mol-1 ). The composite shows the robustness toward solvent and temperatures, all polymerizations using above monomers and catalyzing by GOx&DhHP-6@ZIF-8 exhibits high monomer conversion (>85%) and narrow molar mass dispersity (<1.3). Besides, acrylic and acrylamide monomers such as 2-hydroxyethyl acrylate and N,N-dimethylacrylamide are also carried to demonstrate the broad applicability. Proton nuclear magnetic resonance characterization and chain extension experiments confirm the retaining end groups of the resultant polymers, which is a significant feature of living polymerization. More importantly, the process of recycling the composite through a centrifuge is simplistic, and the composite still maintains similar activity compared to the original composites after five times. This low-cost and easily separated composite catalyst represents a versatile strategy to synthesize well-defined functional polymers suitable for industrial-scale production.

Quaternization of Poly(2-diethyl aminoethyl methacrylate) Brush-Grafted Magnetic Mesoporous Nanoparticles Using 2-Iodoethanol for Removing Anionic Dyes

Magnetic mesoporous silica nanoparticles (Fe3O4-MSNs) were successfully synthesized with a relatively high surface area of 568 m2g−1. Fe3O4-MSNs were then modified with poly(2-diethyl aminoethyl methacrylate) (PDEAEMA) brushes using surface-initiated ARGET atom transfer radical polymerization (ATRP) (Fe3O4@MSN-PDMAEMA). Since the charge of PDEAEMA is externally regulated by solution pH, tertiary amines in the polymer chains were quaternized using 2-iodoethanol to obtain cationic polymer chains with a permanent positive charge (Fe3O4@MSN-QPDMAEMA). The intensity of the C−O peak in the C1s X-ray photoelectron spectrum increased after reaction with 2-iodoethanol, suggesting that the quaternization process was successful. The applicability of the synthesized materials on the removal of methyl orange (MO), and sunset yellow (E110) dyes from an aqueous solution was examined. The effects of pH, contact time, and initial dyes concentrations on the removal performance were investigated by batch experiments. The results showed that the Fe3O4@MSN-PDMAEMA sample exhibited a weak adsorption performance toward both MO and E110, compared with Fe3O4@MSN-QPDMAEMA at a pH level above 5. The maximum adsorption capacities of MO and E110 using Fe3O4@MSN-QPDMAEMA were 294 mg g−1 and 194.8 mg g−1, respectively.

Zinc oxide enhancing hydrophilicity to [polytetrafluoroethylene-graft-poly(methyl methacrylate)]-graft-poly(2-(diethylamino)ethyl methacrylate) films

The low reactivity of polytetrafluoroethylene (PTFE) switches up through grafting reactions with acrylic monomers such as methyl methacrylate (MMA) and 2-(diethylamino)ethyl methacrylate (DEAEMA). (PTFE-g-PMMA)-g-PDEAEMA copolymer enhances its hydrophilic behavior through the coating of ZnO. Co-60 is used as the radical initiator source to perform a graft copolymerization through a two-step route, first using pre-irradiation oxidative to graft MMA, followed by direct irradiation to graft DEAEMA. Experimental parameters dose, solvent, and monomer concentration are studied. The characterization by infrared spectroscopy (FTIR-ATR), Raman spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA), is complemented by physicochemical studies of swelling and drop water contact angle. The ZnO-loaded (PTFE-g-PMMA)-g-PDEAEMA films are structured for multifunctional aims, as expected for their organic/inorganic composition.

Janus particles with pH switchable properties for high-efficiency adsorption of PPCPs in water

Pharmaceuticals and personal care products (PPCPs) are emerging pollutants and have received increasing attention in recent years. The regeneration of conventional adsorption materials used to remove PPCPs involves the desorption of secondary organic pollution, which is harmful and problematic. In this work, the impact of pH-responsive magnetic Janus particle catalysts on PPCPs’ performance of high-efficiency adsorption and degradation was studied. Magnetic core-shell Fe3O4@SiO2 nanoparticles were prepared via the STÖBER method. Polylactic acid (PLA) was grafted using a template method, and the polymerization of pH-responsive monomer 2-(diethylamino)ethyl methacrylate (DEAEMA) was initiated to obtain the pH-responsive magnetic Janus particles (Janus-Fe-P). SEM (scanning electron microscopy), particle size analysis, TEM (transmission electron microscopy), and N2 adsorption-desorption tests were used to characterize the morphology, magnetic property, and pH-responsive performance of the Janus-F-P. The Janus-F-P was used in the adsorptions of two kinds of representative PPCPs, i.e., hydrophilic (antipyrine) and hydrophobic (tiamulin), under neutral conditions. Commercially available NORIT CN activated carbon was used for comparison, and the adsorption results showed that the adsorption efficiency of Janus particles was higher than that of activated carbon. Therefore, Janus-F-P could be used to efficiently catalyze the degradation of adsorbed PPCPs in the Fenton/hydroxylamine system. The removal rate of PPCPs was above 85 % after repeated use (5 times).

PH-Responsive Capsule Polymer Particles Prepared by Interfacial Photo-Cross-Linking: Effect of the Alkyl Chain Length of the pH-Responsive Monomer.

pH-responsive capsule particles have immense potential for use in various advanced fields, such as microreactors and drug delivery. Moreover, the interfacial photo-cross-linking of spherical polymer particles is a promising strategy to create various functional capsule particles. In this study, pH-responsive capsule polymer particles were prepared by interfacial photo-cross-linking with photo-reactive polymers possessing different pH-responsive monomer units of different alkyl chain lengths, namely, 2-dimethylaminoethyl methacrylate, 2-diethylaminoethyl methacrylate, and 2-diisopropylaminoethyl methacrylate. Using these different pH-responsive monomers, regulation of the controlled release properties of pH-responsive capsule particles was achieved. All capsule particles prepared from these three different polymers released encapsulated molecules under acidic conditions; however, more acidic conditions were necessary for releasing encapsulated molecules with the increasing alkyl chain length. The afforded results indicated that pH-responsive monomers of different alkyl chain lengths could be successfully employed to regulate the pH-responsive controlled release property of the capsule particles prepared by interfacial photo-cross-linking.

Exploring novel carrier for improving bioavailability of Itraconazole: Solid dispersion through hot-melt extrusion

Kollicoat® Smartseal (Methyl methacrylate and diethylaminoethyl methacrylate copolymer dispersion) which is used for taste masking and moisture protection, has shown the ability for forming solid dispersion. The present study aimed to check its feasibility for improvement of pharmacokinetics when studied in-vivo in comparison to model high melting point drug-like Itraconazole. Hot-melt extrusion (HME) is a very well commercially accepted technology for solubility enhancement. However, there are limited polymers that can be utilized due to narrow processing window, low thermoplastic behavior or impart stability to the formed amorphous solid dispersion. Thus, having a carrier, which can address all these concerns, will give the industry an additional choice of the carrier for the development of formulations. Thus, the authors have tried to address this issue and demonstrated the ability of the novel carrier to be exploited into HME technology. Solid dispersions of Itraconazole were prepared, characterized, and tested for in-vivo performance in rats. The results indicated that the carrier exhibited good thermoplastic behavior over a temperature range of 120 °C–220 °C. Itraconazole had a plasticizing effect on the carrier. The in-vitro results indicated 20 fold improved solubility over plain Itraconazole. The results of thermal analysis fosters the possibility of the formation of solid solution which converts into an amorphous form. Kollicoat® Smartseal has shown high potential as a carrier to be used in HME for solubility enhancement of highly insoluble drugs like Itraconazole. It offered no processing challenges and the in-vivo results are in good agreement with in-vitro studies.

Degradability of poly(ether-urethanes) and poly(ether-urethane)/acrylic hybrids by bacterial consortia of soil

An enrichment culture strategy was used to obtain natural consortia from soil in order to study the biodegradability of poly(ether-urethanes) (PUE). PUE were synthesized with different aliphatic diisocyanate group, termed PUIPDI and PUHMDI. In addition, PUE/acrylic hybrids, termed PUH90:DEA10 and PUH70:DEA30 consisted of PUHMDI and increasing ratio of 2-(diethylamino)ethyl methacrylate (DEA) were tested. PUIPDI was biodeteriorated through urea-bond hydrolysis by a consortium dominated by Acinetobacter. A higher biodeterioration rate was demonstrated for PUHMDI, which exhibited large surface holes and a greater weight loss. The hydrolysis of ester-urethane bonds and the oxidation of soft-segment ether bonds were the key reactions identified, possibly by Acinetobacter, Mycobacterium, Sphingopyxis and Pseudomonas, which were present in this consortium. Diverse metabolic functions were also predicted. The addition of DEA favored the biodegradability of PUH:DEA hybrids demonstrated by the increased weight loss, swelling degree and the hydrolysis of DEA-ester bond. Urethane and ether bonds degradation were also detected. PUH:DEA hybrids selected even bacterial consortia, most likely by allowing better access to the nutrients. Pseudomonadaceae and Bradyrhizobiaceae families got relevance in these consortia and their outstanding features were cell mobility and quorum sensing. This work has provided a deeper insight into PUE biodegradation by proposing the chemical mechanisms, bacterial taxa and functions that could be implicated.

A Self-Healing Ionic Liquid-Based Ionically Cross-Linked Gel Polymer Electrolyte for Electrochromic Devices.

An ionic liquid-based ionically cross-linked gel polymer electrolyte (GPE-ILs) was successfully synthesized using acrylic acid, 2-diethylaminoethyl methacrylate, methyl methacrylate, and ionic liquids. Electrochromic devices (ECDs) with an architecture of glass/FTO/WO3/GPE-ILs/FTO/glass were fabricated by a laminating technology. The devices showed performances of large optical modulation of 49.9% at 650 nm, short switching times with the coloration time (tc) of 7 s and the bleaching time (tb) of 4 s, high coloration efficiency of 96.2 cm2 C−1, and cycling stability of 200 cycles. The GPE-ILs exhibits high ionic conductivity, superior thermal stability and good self-healing ability. GPE-ILs demonstrates an ionic conductivity of 3.19 × 10−3 S cm−1 at 25 °C and the same ions migration behaviors with most widely used liquid electrolyte between −10 and 80 °C maintains more than 80% of its tensile strength after self-healing and received only 5% weight loss at 300 °C.