Highly Elastic,Bioresorbable Polymeric Materials for Stretchable,Transient Electronic Systems

Substrates or encapsulants in soft and stretchable formats are key components for transient,bioresorbable electronic systems;however,elastomeric polymers with desired mechanical and biochemical properties are very limited compared to nontransient counterparts.Here,we introduce a bioresorbable elastomer,poly(glycolide-co-ε-caprolactone)(PGCL),that contains excellent material properties including high elongation-at-break(<1300%),resilience and toughness,and tunable dissolution behaviors.Exploitation of PGCLs as polymer matrices,in combination with conducing polymers,yields stretchable,conductive composites for degradable interconnects,sensors,and actuators,which can reliably function under external strains.Integration of device components with wireless modules demonstrates elastic,transient electronic suture system with on-demand drug delivery for rapid recovery of postsurgical wounds in soft,time-dynamic tissues.

Evaluation of Rhizobium tropici-Derived Extracellular Polymeric Substances on Selected Soil Properties, Seed Germination, and Growth of Black-Eyed Peas (Vigna unguiculata)

Rhizobium tropici-derived extracellular polymeric substances (EPS) have been used in soils to enhance soil structures and mitigate soil erosions. However, information on their use to improve soil health and fertility indicators, and plant growth is limited. In a greenhouse study, we investigated their effects on some soil health, soil fertility indices, and the growth of black-eyed peas (Vigna unguiculate). Results showed that soils incubated with EPS significantly increased basal soil respiration, soil microbial biomass, permanganate oxidizable carbon (POC), and potentially mineralizable nitrogen (PMN). The EPS shifted microbial populations from bacteria to fungi and Gram (−ve) to Gram ( ve) bacteria. However, it had little or no effects on soil pH, soil organic matter (SOM), and cation exchange capacity (CEC). The EPS decreased soil moisture loss, increased soil aggregate stability, but delayed blacked-eyed peas germinations in the soils. At 0.1% (w/w) concentrations in soils, there was increase in plant root nodulations and vegetative growth. This study was carried out within 40 days of incubating soils with EPS or growing the black-eyed peas in a greenhouse study. The plant growth parameters were taken before flowering and fruiting. Further studies of the effects of incubating soils with the extracellular polymeric substances on plant growth. Soil microbial biomass, microbial diversities, and other soil fertility indices are deemed necessary.

Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability

Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications.

Boosting the cycling stability of all-solid-state lithium metal batteries through MOF-based polymeric protective layers

Solid-state electrolytes(SSEs)play a pivotal role in advancing next-generation lithium metal battery technology.However,they commonly encounter substantial interfacial resistance and poor stability when interfacing with lithium metal,hindering practical applications.Herein,we introduce a flexible metal-organic framework(MOF:NUS-6)-incorporated polymeric layer,denoted as NP,designed to protect the sodium superionic conductor(NASICON)-type Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)electrolyte from Li metal anodes.The NP matrix establishes a soft interface with the LATP surface,effectively reducing voids and gaps that may arise between the LATP electrolyte and Li metal.Moreover,the MOF component in NP enhances ionic conductivity,offers abundant Li^(+)transport sites,and provides hierarchical ion channels,ensuring a homogeneous Li^(+)flow and thus effectively inhibiting Li dendrite formation.Utilizing NP,we fabricate Li symmetrical cells cycled for over 1600 h at 0.2 mA cm^(-2)and all-solid-state LiINP-LATPI LiFePO_(4)batteries,achieving a remarkable 99.3%capacity retention after 200 cycles at 0.2 C.This work outlines a general strategy for designing long-lasting and stable solid-state Li metal batteries.

Improved Plasmonic Hot‑Electron Capture in Au Nanoparticle/Polymeric Carbon Nitride by Pt Single Atoms for Broad‑Spectrum Photocatalytic H_(2)Evolution

ABSTRACT Rationally designing broad-spectrum photocatalysts to harvest whole visible-light region photons and enhance solar energy conversion is a“holy grail”for researchers,but is still a challenging issue.Herein,based on the common polymeric carbon nitride(PCN),a hybrid co-catalysts system comprising plasmonic Au nanoparticles(NPs)and atomically dispersed Pt single atoms(PtSAs)with different functions was constructed to address this challenge.For the dual co-catalysts decorated PCN(PtSAs–Au_(2.5)/PCN),the PCN is photoexcited to generate electrons under UV and short-wavelength visible light,and the synergetic Au NPs and PtSAs not only accelerate charge separation and transfer though Schottky junctions and metal-support bond but also act as the co-catalysts for H_(2) evolution.Furthermore,the Au NPs absorb long-wavelength visible light owing to its localized surface plasmon resonance,and the adjacent PtSAs trap the plasmonic hot-electrons for H_(2) evolution via direct electron transfer effect.Consequently,the PtSAs–Au_(2.5)/PCN exhibits excellent broad-spectrum photocatalytic H_(2) evolution activity with the H_(2) evolution rate of 8.8 mmol g^(−1) h^(−1) at 420 nm and 264μmol g^(−1) h^(−1) at 550 nm,much higher than that of Au_(2.5)/PCN and PtSAs–PCN,respectively.This work provides a new strategy to design broad-spectrum photocatalysts for energy conversion reaction.

Advances in the development of amorphous solid dispersions:The role of polymeric carriers

Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To prepare the solid dispersions,there are many polymers with various physicochemical and thermochemical characteristics available for use in ASD formulations.Polymer selection is of great importance because it influences the stability,solubility and dissolution rates,manufacturing process,and bioavailability of the ASD.This review article provides a comprehensive overview of ASDs from the perspectives of physicochemical characteristics of polymers,formulation designs and preparation methods.Furthermore,considerations of safety and regulatory requirements along with the studies recommended for characterizing and evaluating polymeric carriers are briefly discussed.

An Intelligent Manufacturing Platform of Polymers:Polymeric Material Genome Engineering

Polymeric materials with excellent performance are the foundation for developing high-level technology and advanced manufacturing.Polymeric material genome engineering(PMGE)is becoming a vital platform for the intelligent manufacturing of polymeric materials.However,the development of PMGE is still in its infancy,and many issues remain to be addressed.In this perspective,we elaborate on the PMGE concepts,summarize the state-of-the-art research and achievements,and highlight the challenges and prospects in this field.In particular,we focus on property estimation approaches,including property proxy prediction and machine learning prediction of polymer properties.The potential engineering applications of PMGE are discussed,including the fields of advanced composites,polymeric materials for communications,and integrated circuits.

Relaxin-encapsulated polymeric metformin nanoparticles remodel tumor immune microenvironment by reducing CAFs for efficient triple-negative breast cancer immunotherapy

Cancer-associated fibroblasts(CAFs)are one of the most abundant stromal cells in the tumor microenvironment which mediate desmoplastic response and are the primary driver for an immunosuppressive microenvironment,leading to the failure of triple-negative breast cancer(TNBC)immunotherapy.Therefore,depleting CAFs may enhance the effect of immunotherapy(such as PD-L1 antibody).Relaxin(RLN)has been demonstrated to significantly improve transforming growth factor-β(TGF-β)induced CAFs activation and tumor immunosuppressive microenvironment.However,the short half-life and systemic vasodilation of RLN limit its in vivo efficacy.Here,plasmid encoding relaxin(pRLN)to locally express RLN was delivered with a new positively charged polymer named polymeric metformin(PolyMet),which could increase gene transfer efficiency significantly and have low toxicity that have been certified by our lab before.In order to improve the stability of pRLN in vivo,this complex was further formed lipid poly-γ-glutamic acid(PGA)/PolyMetpRLN nanoparticle(LPPR).The particle size of LPPR was 205.5±2.9 nm,and the zeta potential was+55.4±1.6 mV.LPPR displayed excellent tumor penetrating efficacy and weaken proliferation of CAFs in 4T1luc/CAFs tumor spheres in vitro.In vivo,it could reverse aberrantly activated CAFs by decreasing the expression of profibrogenic cytokine and remove the physical barrier to reshape the tumor stromal microenvironment,which enabled a 2.2-fold increase in cytotoxic T cell infiltration within the tumor and a decrease in immunosuppressive cells infiltration.Thus,LPPR was observed retarded tumor growth by itself in the 4T1 tumor bearing-mouse,and the reshaped immune microenvironment further led to facilitate antitumor effect when it combined with PD-L1 antibody(aPD-L1).Altogether,this study presented a novel therapeutic approach against tumor stroma using LPPR to achieve a combination regimen with immune checkpoint blockade therapy against the desmoplastic TNBC model.

Effect of extracellular polymeric substances on Dolichospermum aggregation during temperature rise

Dolichospermum,a typical model filamentous of cyanobacteria,has the potential to cause severely bloom.Extracellular polymeric substances(EPSs)are considered to influence the aggregation of the algae,and temperature is a significant factor affecting EPSs secretion.However,the mechanism of how EPSs affects the aggregation of Dolichospermum is still unclear because the structure and composition of EPSs are complex.In this study,the effects of EPSs on the aggregation of Dolichospermum during the rise of temperature(7-37℃)were determined.The results showed that the concentration of extracellular polysaccharides and proteins changed significantly with increasing temperature(P<0.01).Firstly,during the increasing temperature,the polysaccharide content of EPSs increased from 20.34 to 54.64 mg/L,and the polysaccharides in the soluble EPS(S-EPS)layer changed significantly.The protein content reached maximum value at 21℃(14.52 mg/L)and varied significantly in S-EPS and loosely bound EPS(LB-EPS).In the EPSs matrix,humus substances and protein were main components of S-EPS and LB-EPS,and protein was the main component of tightly bound EPS(TB-EPS).Secondly,the cell density of Dolichospermum increased during the temperature rise while the aggregation ratio decreased.Moreover,zeta potential and surface thermodynamic analysis of Dolichospermum revealed that the interfacial free energy and electrostatic repulsion increased gradually with increasing temperature,which further reduced the aggregation of Dolichospermum.Finally,principal component analysis(PCA)analysis showed the aggregation of Dolichospermum was directly related to the changes of protein in EPSs(especially S-EPS and LB-EPS)and zeta potential,and polysaccharides in EPSs inhibited the aggregation of Dolichospermum.Based on these results,it was illustrated that the composition and concentration of EPSs affected the cell surface properties of Dolichospermum with the change of temperature and thus affected the aggregation of Dolichospermum.

Role of extracellular polymeric substances in resistance to allelochemical stress on Microcystis aeruginsosa and its mechanism

Using allelochemicals to suppress cyanobacteria growth is a prospective method for its high efficiency and ecological safety.However,the suppression efficiency is affected inevitably by the extracellular polymeric substances(EPS)produced by cyanobacteria,and the knowledge about the roles of EPS in resistance to allelochemical stress is scarce.For the study,two typical anti-cyanobacterial allelochemicals were adopted to investigate the role of EPS in resistance to allelochemical stress on Microcystis aeruginosa.Results show that EPS was crucial in alleviating the toxicity of allelochemicals to algae,especially in stabilizing the metabolism and photosynthetic activity of algal cells.The aggregation rate of algal cells increased with the increase of EPS secretion,which alleviated the stress of allelopathy.Tryptophan proteins and humic acids in EPS provided a binding site for allelochemicals,and the EPS-allelochemicals complex were formed by chemical bonding.This study improved our comprehension of the role of EPS in algal inhibition by allelochemicals.

Dissolvable polymeric microneedles loaded with aspirin for antiplatelet aggregation

To reduce mucosal damage in the gastrointestinal tract caused by aspirin,we developed a dissolvable polymeric microneedle(MN)patch loaded with aspirin.Biodegradable polymers provide mechanical strength to the MNs.The MN tips punctured the cuticle of the skin and dissolved when in contact with the subcutaneous tissue.The aspirin in the MN patch is delivered continuously through an array of micropores created by the punctures,providing a stable plasma concentration of aspirin.The factors affecting the stability of aspirin during MNs fabrication were comprehensively analyzed,and the hydrolysis rate of aspirin in the MNs was less than 2%.Compared to oral administration,MN administration not only had a smoother plasma concentration curve but also resulted in a lower effective dose of antiplatelet aggregation.Aspirin-loaded MNs were mildly irritating to the skin,causing only slight erythema on the skin and recovery within 24 h.In summary,aspirin-loaded MNs provide a new method to reduce gastrointestinal adverse effects in patients requiring aspirin regularly.

Synthesis, Characterization and Properties of Polymeric p-Benzoyl-4,4'-Diaminobenzoylaniline

An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of carbon atoms in the amide group at 166 ppm, which was demonstrated by the solid nuclear magnetic resonance carbon spectrum. It was shown to be the stretching vibration absorption peak of the amide N-H bond at 3342 cm−1 by Fourier infrared (FT-IR) spectroscopy. It was obtained that the energy band near 1100 - 1276 cm−1 belongs to the absorption peak of the para-substituted benzene ring and the band near 2977 cm−1 was the C-H stretching vibration peak of the benzene ring by Raman spectroscopy. The molecular structure of the synthesized polyamide compound was confirmed by FT-IR, Raman, and solid 13C-NMR spectroscopies. It was proved that the polymer is stable up to 300˚C and has a relatively high stability by the thermogravimetric analysis. It was also confirmed by the fluorescence spectrum that it has a strong blue fluorescence near 420 nm. The morphological characteristics of the polymer were further demonstrated by electron scanning electron microscopy (SEM). The properties of polymeric p-benzoyl-4,4'-diaminobenzoyl-aniline were found to emit strong blue fluorescence and have good thermal stability, making it a promising functional material for fluorescence in the blue region with potential for large-scale applications.

Sodium-Coordinated Polymeric Phthalocyanines as Stable High-Capacity Organic Anodes for Sodium-Ion Batteries

Sodium-ion batteries(SIBs)have attracted considerable interest as an alternative to lithium-ion batteries owing to their similar electrochemical performance and superior long-term cycle stability.Organic materials are regarded as promising anode materials for constructing SIBs with high capacity and good retention.However,utilization of organic materials is rather limited by their low energy density and poor stability at high current densities.To overcome these limitations,we utilized a novel polymeric disodium phthalocyanines(pNaPc)as SIB anodes to provide stable coordination sites for Na ions as well as to enhance the stability at high current density.By varying the linker type during a one-pot cyclization and polymerization process,two pNaPc anodes with O-(O-pNaPc)and S-linkers(S-pNaPc)were prepared,and their structural and electrochemical properties were investigated.The O-pNaPc binds Na ions with a lower binding energy compared with S-pNaPc,which leads to more facile Na-ion coordination/dissociation when engaged as SIB anode.The use of O-pNaPc significantly improves the redox kinetics and cycle stability and allows the fabrication of a full cell against Na_(3)V_(2)(PO_(4))_(2)F_(3)/C cathode,which demonstrates its practical application with high energy density(288 Wh kg^(-1))and high power density(149 W kg^(-1)).

A fast ionic transport copolymeric network for stable quasi-solid lithium metal battery

Solid-state lithium(Li) metal batteries overwhelm the lithium-ion batteries by harvesting high energy from Li metal anode with ultrahigh capacities and gaining excellent safety from solid electrolytes.However,the uncontrollable solvents in solid electrolytes usually aggravate poor interfacial contact with lithium metal anode and deteriorate Li^(+) pathways.Here a copolymeric network-structured ion conductor by rationally integrating cellulose nanofibril as a two-in-one functional material is employed to anchor the solvent.Taking advantages of tightly anchoring of cellulose nanofibril to solvent,the asconstructed quasi-solid polymer-based electrolyte offers rapid Li^(+) transport channels and realizes effective Li-dendrite suppression,which enables high ionic conductivity of 1.93 × 10^(-3)S cm^(-1) at room temperature,long-term Li plating/stripping over 1900 h,and high capacity retention of 99%.This work provides a fresh strategy for creating solid electrolytes that meet both high ionic conductivity and interfacial stability requirements for practical solid-state lithium metal battery.

Reliability Based Analysis of Ground Improvement Using a Polymeric Chemical Stabilizer

In view of the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them, there is a need to investigate modern trends in ground improvement techniques in order to determine their reliability. This study is thus aimed at using the reliability based approach to analyze the use of polyvinyl alcohol (PVA) in combination with 1,2,3,4 Butane-tetracarboxylic acid (BTCA) for ground improvement. This study is necessary given the challenges posed by the nature of expansive soil to structural stability which makes it necessary in some cases to improve the soils before structures can be placed on them. Simplex lattice design was employed to build the design of experiment before experimental investigations were carried out on the PVA-BTCA treated soft soils. Reliability indices were computed on the basis of the 28th day unconfined compressive strength (UCS) of the treated soil. Reliability index models were developed using the Scheffe’s technique and optimized using excel solver. From analysis of results, reliability model developed proved adequate at 5% level of significance. PVA-BTCA combination provided a potential reliability or probability of success of 99.936% at components combination of: 98.4256% for soil, 1.2352% for PVA, 0.3392% for BTCA and 15.9934% for water. It was therefore recommended that financial implications of using PVA-BTCA for stabilization be compared to those of conventional methods, in order to compare their performance-cost ratio.

Synthesis, Characterization and Properties of Polymeric p-Benzoyl-4,4'-Diaminobenzoylaniline

An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of carbon atoms in the amide group at 166 ppm, which was demonstrated by the solid nuclear magnetic resonance carbon spectrum. It was shown to be the stretching vibration absorption peak of the amide N-H bond at 3342 cm−1 by Fourier infrared (FT-IR) spectroscopy. It was obtained that the energy band near 1100 - 1276 cm−1 belongs to the absorption peak of the para-substituted benzene ring and the band near 2977 cm−1 was the C-H stretching vibration peak of the benzene ring by Raman spectroscopy. The molecular structure of the synthesized polyamide compound was confirmed by FT-IR, Raman, and solid 13C-NMR spectroscopies. It was proved that the polymer is stable up to 300˚C and has a relatively high stability by the thermogravimetric analysis. It was also confirmed by the fluorescence spectrum that it has a strong blue fluorescence near 420 nm. The morphological characteristics of the polymer were further demonstrated by electron scanning electron microscopy (SEM). The properties of polymeric p-benzoyl-4,4'-diaminobenzoyl-aniline were found to emit strong blue fluorescence and have good thermal stability, making it a promising functional material for fluorescence in the blue region with potential for large-scale applications.

In-situ polymerized PEO-based solid electrolytes contribute better Li metal batteries:Challenges,strategies,and perspectives

Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)with good electrochemical stability and excellent Li salt solubility are considered as one of the most promising SPEs for solid-state lithium metal batteries(SSLMBs).However,PEO-based SPEs suffer from low ionic conductivity at room temperature and high interfacial resistance with the electrodes due to poor interfacial contact,seriously hindering their practical applications.As an emerging technology,in-situ polymerization process has been widely used in PEO-based SPEs because it can effectively increase Li-ion transport at the interface and improve the interfacial contact between the electrolyte and electrodes.Herein,we review recent advances in design and fabrication of in-situ polymerized PEO-based SPEs to realize enhanced performance in LMBs.The merits and current challenges of various SPEs,as well as their stabilizing strategies are presented.Furthermore,various in-situ polymerization methods(such as free radical polymerization,cationic polymerization,anionic polymerization)for the preparation of PEO-based SPEs are summarized.In addition,the application of in-situ polymerization technology in PEO-based SPEs for adjustment of the functional units and addition of different functional filler materials was systematically discussed to explore the design concepts,methods and working mechanisms.Finally,the challenges and future prospects of in-situ polymerized PEO-based SPEs for SSLMBs are also proposed.

Comprehension-driven design of advanced multi-block single-ion conducting polymer electrolytes for high-performance lithium-metal batteries

The continuously growing importance of batteries for powering(hybrid)electric vehicles and storing renewable energy has prompted a renewed focus on lithium-metal batteries(LMBs)in recent years,as its high theoretical specific capacity of about 3860 mA h g^(-1) and very low redox potential(-3.04 V vs.the standard hydrogen electrode)promise substantially higher energy densities compared to current lithium-ion batteries(LIBs)[1].However,lithium metal electrodes face severe challenges associated with the risk of dendritic lithium deposition and the high reactivity with traditional organic liquid electrolytes,resulting in a continuous loss of electrochemically active lithium and a relatively low Coulombic efficiency[2].To address these challenges,solid inorganic and polymer electrolytes have emerged as a potentially saferalternative.

Effect of electron-electron interaction on polarization process of exciton and biexciton in conjugated polymer

By using one-dimensional tight-binding model modified to include electron-electric field interaction and electron-electron interaction,we theoretically explore the polarization process of exciton and biexciton in cis-polyacetylene.The dynamical simulation is performed by adopting the non-adiabatic evolution approach.The results show that under the effect of moderate electric field,when the strength of electron-electron interaction is weak,the singlet exciton is stable but its polarization presents obvious oscillation.With the enhancement of interaction,it is dissociated into polaron pairs,the spin-flip of which can be observed through modulating the interaction strength.For the triplet exciton,the strong electron-electron interaction restrains its normal polarization,but it is still stable.In the case of biexciton,the strong electron-electron interaction not only dissociate it,but also flip its charge distribution.The yield of the possible states formed after the dissociation of exciton and biexciton is also calculated.

Influence of Mass Ratio of Resin and Stabilizer on Mechanical Properties of Mo Fiber-reinforced Granite Polymer Composite

Because inferior mechanical strength of granite polymer composite(GPC)has become the main drawback limiting its application and popularization,Mo fibers were added into(GPC)to improve its mechanical strength.Mechanical properties of matrix materials with different mass ratio of resin and stabilizer(MRRS)were investigated systematically.The influences of MRRS on interface bonding strength of Mo fiber-matrix,wettability and mechanical strength of GPC were discussed,respectively,and the theoretical calculation result of MRRS k was obtained,with the optimal value of k=4.When k=4,tensile strength,tensile strain and fracture stress of the cured resin achieve the maximum values.But for k=7,the corresponding values reach the minimum.With the increase of MRRS k,surface free energy of the cured resin first increases and then decreases,while contact angles between Mo sample and matrix have displayed the opposite trend.Wettability of resin to Mo fiber is the best at k=4.Pulling load of Mo fiber and interface bonding strength appear the maximum at k=4,followed by k=5,k=3 the third,and k=7 the minimum.When k=4,mechanical properties of Mo fiber-reinforced GPC are optimal,which is consistent with the result of theoretical calculation.This study is of great significance to get better component formulas of Mo fiber reinforced GPC and to improve its application in machine tools.