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Androgenic alopecia (AGA) affects both men and women worldwide. New blood vessel formation can restore blood supply and stimulate the hair regrowth cycle. Recently, our group reported that 2-deoxy-D-ribose (2dDR) is 80%–90% as effective as VEGF in the stimulation of neovascularization in in vitro models and in a chick bioassay. In this study, we aimed to assess the effect of 2dDR on hair growth. We prepared an alginate gel containing 2dDR, polypropylene glycol, and phenoxyethanol. AGA was developed in C57BL6 mice by intraperitoneally injecting testosterone (TE). A dihydrotestosterone (DHT)-treated group was used as a negative control, a minoxidil group was used as a positive control, and we included groups treated with 2dDR gel and a combination of 2dDR and minoxidil. Each treatment was applied for 20 days. Both groups treated with 2dDR gel and minoxidil stimulated the morphogenesis of hair follicles. H&E-stained skin sections of C57BL/6 mice demonstrated an increase in length, diameter, hair follicle density, anagen/telogen ratio, diameter of hair follicles, area of the hair bulb covered in melanin, and an increase in the number of blood vessels. Masson's trichrome staining showed an increase in the area of the hair bulb covered in melanin. The effects of the FDA-approved drug (minoxidil) on hair growth were similar to those of 2dDR (80%–90%). No significant benefit were observed by applying a combination of minoxidil with 2dDR. We conclude that 2dDR gel has potential for the treatment of androgenic alopecia and possibly other alopecia conditions where stimulation of hair regrowth is desirable, such as after chemotherapy. The mechanism of activity of 2dDR remains to be established. [ABSTRACT FROM AUTHOR]

In this study, polypropylene glycol (PPG) and isophorone diisocyanate (IPDI) with molecular weights (Mws) ranging from 8000 to 18,000 were used as starting materials to synthesize silylated polyurethanes (SLPUs) according to alkoxysilanes. FT-IR, GPC, and DSC were used to analyze composition and structure of the synthesized SLPU. Shore A-type, C-type hardness testers, and UTM were used to measure hardness, tensile strength, and elongation, respectively. It was revealed that mechanical properties and viscosity increased as the Mw of PPG increased. In particular, PPG 12,000 and (3-aminopropyl) triethoxysilane SLPU showed excellent storage stability and good mechanical properties. When alkoxysilane was applied as a capping agent, it was found that methoxysilane had a faster curing speed than ethoxysilane. However, it had insufficient workability and storage stability. Mechanical properties of ethoxysilane were relatively superior to those of methoxysilane. [ABSTRACT FROM AUTHOR]

New shape‐memory networks composed of both reversible Diels–Alder covalent crosslinks and the hydrogen and π–π stacking bonds of triazine functional groups, with self‐healing properties as a result of the reversibility of these dynamic bonds were achieved from a furfuryl‐functionalized copoly(triazine‐r‐polypropylene glycol‐r‐polydimethylsiloxane), crosslinked with a maleimide end‐capped polycaprolactone and a long polycaprolactone‐based chain extender. The presence of multiple dynamic bonds, including the Diels–Alder and triazine‐derived π–π stacking and H‐bond interactions as well as the enhanced network mobility arising from polypropylene glycol, polydimethylsiloxane and polycaprolactone segments upon triggering the shape memory effect resulted in a material with high toughness (~200 MPa J−1) and efficient healing ability (with a recoveries of tensile strength and toughness after being cut and healed of 87% and 94%, respectively). Highlights: Furfuryl dichlorotriazine was coupled with PPG and PDMS forming a copolymer.The copolymer was crosslinked with PCL‐dimaleimide and PCL‐difuran extender.Multiple dynamic bonds (Diels–Alder, π–π stacking and H‐bond) were present.The network showed high toughness and good healing performance. [ABSTRACT FROM AUTHOR]

In the context of growing interest in phosphonic acid proton exchange membranes (PEMs) for fuel cell applications, we report on new PEMs containing low‐cost polyethylene oxide (PEO) covalently linked by siloxane bonds, SiOSi, to phosphonic acid (PA). Key chemistry in the formation of these membranes involves hydrolysis and condensation reactions of triethoxysilyl propyl capped PEO and pre‐hydrolyzed dimethyl phosphonatoethyltrimethoxysilane (DMPTMS) giving PEO‐Si2O3‐PA and cross‐linked chain PEO‐Si2O3‐PEO organosilsesquioxane components. The Si2O3 can enhance membrane thermal and mechanical properties. The membrane formulations were varied by (a) reagent ratios (b) PEO molecular weights or using polypropylene oxide (PPO) (c) incorporating chain extending groups methylene diphenyl diisocyanate (MDI) or hexamethylene diisocyanate (HDI). These variations provided five membrane families, one of which afforded a complete group of robust membranes with weight% x of PA, PAx in range PA0–PA33. These were studied using ATR‐FTIR, dry membrane water uptake capacity, ion exchange capacity (IEC), and conductivity from room temperature to 120°C at 100% relative humidity. Conductivity increased with PAx reaching 15 mS cm−1 at 120°C, activation energy 0.1 eV, for membrane PA33 for which thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and energy dispersive X‐ray analysis (EDAX) are reported. A comparative performance of the five membrane families is presented. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP) is emerging as a powerful tool for fabricating tissue engineering (TE) scaffolds, particularly for vascular TE and the development of representative in vitro vascular wall models. For the latter, biomaterials should mimick the biological and mechanical properties of native blood vessels. To fabricate tubular constructs, the DLP‐printing process is optimized by exploiting acrylate‐endcapped urethane‐based (AUP) polymers as the presence of the acrylate end groups render them suitable for DLP printing and desirable mechanical properties arise from the urethane segments. Four AUP variants are synthesized, exploring polyethylene glycol (PEG) and polypropylene glycol (PPG) backbones with varying acrylate functionalities (di‐acrylate versus hexa‐acrylate), namely UPEG2, UPEG6, UPPG2, and UPPG6. Tubular constructs with precise dimensions and morphology are fabricated. PPG‐based AUP polymers exhibit superior computer‐aided design/manufacturing (CAD/CAM) mimicry compared to PEG‐based derivatives. Construct characterization reveals tunable mechanical properties, with elastic moduli ranging from 45 to 259 kPa, reaching values of the human blood vessels. In particular, UPPG6 shows a two‐fold higher elastic modulus compared to UPPG2. All materials show excellent biocompatibility. Additionally, surface modification with gelatin‐methacryloyl (GELMA) significantly enhances the cytocompatibility of UPPG2 scaffolds. This study demonstrates the feasibility of fabricating tubular constructs with tunable properties using DLP and AUP polymers. [ABSTRACT FROM AUTHOR]

Triterpenoid saponins from the Astragalus species possess valuable effects (cytotoxic, adjuvant, hepatoprotective, neuroprotective, antiviral, etc.). Some also have immunomodulatory activities. Astragalus glycyphyllos is distributed in Bulgaria and mainly accumulates cycloartane saponins. From the overground parts of the species, a triterpenoid cyloartane-type saponin (AGOS3) was isolated by different chromatographic techniques. A quantitative LC-MS method for the determination of the saponin was developed and validated. Further, the saponin was loaded in copolymeric micelles based on triblock copolymers of polyethylene oxide and polypropylene oxide (Pluronics). The LC-MS method was applied on the developed micelles to determine their loading degrees. Afterwards, the possible pharmacological effects of free and encapsulated in polymeric nanoparticles of triterpenoid saponin (1, 5, 10, 25, 50, and 100 µg/mL) were evaluated in isolated murine macrophages and lymphocytes in vitro. Free AGOS3 stimulated proliferation only at the highest tested concentrations (50–100 µg/mL), and the effect was more evident in isolated macrophages. Interestingly, AGOS3-loaded polymeric micelles caused concentration dependency and statistically significant increases in the proliferation of both isolated lymphocytes and macrophages, even at a lower concentration (10 µg/mL). These results could serve as the basis for further research on the immunomodulatory effect of this saponin. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) membranes with excellent dye removal and antibacterial activity are highly desired in dye wastewater treatment, and more importantly environmental protection puts high demands on polymeric membrane materials. In this work, three methacrylate copolymers containing quaternary ammonium salt were synthesized to cast UF membranes. The physicochemical property, structural evolution, dye separation, and antibacterial activity of as‐prepared membranes were systematically investigated. With increased content of the hydrophilic monomer allyl polypropylene glycol (APPG) in the feed, the wettability and positive charge of the resultant membranes were enhanced. Remarkably, the supporting layer of membranes changed from finger‐like pore structure to sponge‐like pore structure by increasing APPG content, and the sponge‐like membranes showed higher retention rates for dyes (99.78% for victoria blue B, 90.49% for methylene blue, and 97.43% for methyl blue) compared with the finger‐like membranes. Besides, the sponge‐like membranes exhibited high rejection for vctoria blue B (>99%) in dye/salt mixture and simultaneously low rejection for salts (<10%), indicating effective selective separation to dye/salt mixture, and also achieved easy regeneration. It was also found that increased hydrophilicity and positive charge endowed membranes with better antibacterial activity. This work will provide an alternative for dye/salt selective separation in dye effluent treatment. [ABSTRACT FROM AUTHOR]

A series of CO2-based thermoplastic polyurethanes (TPUs) were prepared using CO2-based poly(polycarbonate) diol (PPCDL), 4,4′-methylenebis (cyclohexyl isocyanate) (HMDI), and polypropylene glycol (PPG and 1,4-butanediol (BDO) as the raw materials. The mechanical, thermal, optical, and barrier properties shape memory behaviors, while biocompatibility and degradation behaviors of the CO2-based TPUs are also systematically investigated. All the synthesized TPUs are highly transparent amorphous polymers, with one glass transition temperature at ~15–45 °C varying with hard segment content and soft segment composition. When PPG is incorporated into the soft segments, the resultant TPUs exhibit excellent self-healing and shape memory performances with the average shape fixity ratio and shape recovery ratio as high as 98.9% and 88.3%, respectively. Furthermore, the CO2-based TPUs also show superior water vapor permeability resistance, good biocompatibility, and good biodegradation properties, demonstrating their pretty competitive potential in the polyurethane industry applications. [ABSTRACT FROM AUTHOR]

In the present work, N-substituted glutamic acid, polyethylene and polypropylene glycols have been used to design biocompatible copolyesters via Steglich reactions. Due to the presence of alternating hydrophilic and hydrophobic blocks in their structures, these copolyesters are able to form self-stabilized nanoparticle dispersions in aqueous media. The lipophilic core of these nanoparticles can solubilize poorly water-soluble compounds and release them into a model of lipids in a human body. Moreover, the obtained copolyesters possess no cytotoxic effects over a wide concentration range. Thus, we conclude that obtained copolyesters show significant promise for further development as drug delivery systems. [ABSTRACT FROM AUTHOR]

A structural adhesive series of biomass-based polyurethane (Biomass-PU) is synthesized using polypropylene glycol (PPG2000), isosorbide-based polyol (RPO300) as polyols, isophorone diisocyanate (IPDI) as an isocyanate and 4-tert-butylphenol (BP) as a capping agent. Three different equivalent ratios of PPG2000/RPO300, 9/1 (Biomass-PU1), 7/3 (Biomass-PU2), and 1/1 (Biomass-PU3), are evaluated to determine the effect of isosorbide-based polyol content on the properties and the optimizing formulation of biomass-PU structure adhesive. The 9/1 ratio of PPG2000/RPO300 substantially leads to the improvement of impact strength by up to 35 MPa, and the PPG2000/RPO300 = 9/1 ratio exhibits better thermal properties and impact strength than those of other ratios. To achieve more compatibility between biomass-PU structure adhesive and core–shell rubber (CSR) toughener, novel CSRs are successfully synthesized using acryl-PU as a shell and biomass-based PU as a core. The chemical structure of biomass-PU structure adhesives is analyzed through FT-IR Spectroscopy and NCO% titration. Thermal properties are evaluated using TGA and DSC analysis. Their molecular weights are measured by GPC. Also, the core–shell rubber (CSR) with a polyurethane shell is prepared to reinforce the impact strength of Biomass-PU structure adhesive. [ABSTRACT FROM AUTHOR]

The colloidal-chemical properties of oxyethylated polypropylene glycols (pluronics), soluble and slightly soluble in water and containing a hydrophobic polypropylene glycol block with the same length but with different degrees of oxyethylation, were analyzed. It was determined that both pluronics are characterized by high surfactant properties, making it possible to use them as surfactants in heterophase polymerization processes. The observed differences in the kinetic specific features of the polymerization of styrene and methyl methacrylate (average particle diameter and polymerization rate, the character of the monomer conversion—time curves) allowed us to infer that the formation of the polymer-monomer particles occurs by different mechanisms. The obtained results showed that these surfactants are promising for the synthesis of polymer suspensions with a narrow particle size distribution and an average diameter in the range from 0.09 to 1.7 µm. [ABSTRACT FROM AUTHOR]

Low ionic conductivity, narrow electrochemical window and poor mechanical property are the core problems that polymer solid electrolyte is difficult for practical application. Choosing suitable polymer and regulating the ion transport path through inorganic fillers is an important method to solve the above problems. Herein, a polymeric matrix composite solid electrolyte(CSE) was achieved by combining electrospun Li7La3Zr2O12 (LLZO) fibers and highly viscoelastic polypropylene oxide(PPO). The PPO matrix provides the CSE with good mechanical property to 56.75 MPa. While the addition of fibrous LLZO improves the ion transport channels of the CSE, which boosts the ionic conductivity, electrochemical window and ion transport number up to 4.59 × 10− 4 S cm− 1 at room temperature, 5.4 V and 0.74, respectively, when the content of LLZO fiber is 7.5 wt% of PPO polymer. The prepared PPO-LLZO fibers electrolyte can be used in high-voltage solid-state lithium battery and shows good rate and cycle performances. This composite solid electrolyte film and its simplified preparation conditions is beneficial for practical applications in solid-state batteries. [ABSTRACT FROM AUTHOR]

In this study, spherical silica with pore size varied from 30 to 200 Å was synthesized by pseudomorphic transformation at atmospheric pressure. 40–80 Å silica particles with a narrow pore distribution were obtained by using quaternary amine cationic surfactants and different kinds of swelling agents, including polypropylene glycol, 1,3,5‐trimethylbenzene, alkanes, and alkanols. Alkyl imidazolium ionic liquid surfactants were used to synthesize large pore size distribution silica spheres with pore sizes in the range of 110–200 Å. All these silica particles can be synthesized under mild conditions within 12 h, which provides a facile synthesis method for the preparation of a chromatographic matrix with tunable pore size. The method is reproducible and the relative standard deviation of silica sphere pore structure parameters in scaled‐up preparations is less than 6%. The pore size on the fraction of low‐molecular‐weight heparin (LMWH) was investigated in size exclusion chromatography. Matrixes with different pore size distributions have various size exclusion regions. By using UPS‐60‐Diol columns in a twin‐column recirculation separation process, LMWH with >85% heparin with molecular weight within the range of 3000–8000 Da were separated in five‐column volumes. [ABSTRACT FROM AUTHOR]

Polypropylene carbonate (PPC) is a promising candidate of substrate materials used for human wearable devices due to its excellent ductility and biocompatibility. However, PPC is prone to be deformed, thus resulting in poor shape recovery property. One effective solution is to construct composites. In this work, poly (tannic acid) with Fe3+ (FPTA) @ graphene oxide (GO) was added to fabricate FPTA@GO/PPC composites. The results show that FPTA@GO can construct a tight network of hydrogen bonds into PPC to improve shape memory and self‐healing properties. By varying the FPTA@GO content, the composites exhibit tunable shape memory property. Dynamic mechanical analysis confirms that FPTA@GO/PPC composites show better shape memory properties compared with pure PPC. 5 wt% FPTA@GO/PPC composite demonstrates superior shape fixation ratio (Rf = 99%) as well as superior shape recovery ratio (Rr = 94%) in 37°C. Moreover, 5 wt% FPTA@GO/PPC composite possesses great self‐healing efficiency of 81% and tensile strength (17.2 MPa). The UV absorption capacity of 5 wt% FPTA@GO/PPC is increased by 150% (far and mid‐UV regions) and 400% (near‐UV region) compared with pure PPC. Thus, FPTA@GO/PPC composites have potential applications in developing shape memory, self‐healing, and UV‐resistant materials for human wearable devices. [ABSTRACT FROM AUTHOR]

Polyurethane coatings were synthesized through polyaddition polymerization using various polyols. These polyols included polypropylene glycol with different molecular weights, such as PPG-2000, and PPG-1200, as well as 1,4-butanediol. Additionally different contents of bisphenol F; namely 4.5, 11.5, and 24.2%, as well as methylene diphenyl diisocyanate at an NCO/OH ratio of 2.0. The prepolymer polyurethane films were analyzed to study their characteristics using techniques such as Fourier transform infrared spectroscopy, viscosity measurements, thixotropic index analysis, and mechanical property evaluations. The pot life and dry times of polyurethane coating containing 11.5% bisphenol F were 90 minutes and 10 hours (time to touch), respectively, with full hardening achieved at 28 hours. Furthermore, the coating exhibited excellent mechanical properties: tensile strength of 80 N/m², elongation of 260%, adhesion strength of 10 MPa (crosshatch), hardness of 95, and a contact angle of 118°. These properties, coupled with its strong adhesion (10 MPa) to metal surfaces, contributed to its outstanding chemical and corrosion resistance. The coatings obtained from the prepolymer polyurethane based on 11.5% bisphenol F exhibited the highest mechanical properties and water, chemical, and corrosion resistance followed by 4.5%, and 24.2%, respectively. [ABSTRACT FROM AUTHOR]

Shear thickening fluids (STFs) have garnered attention as potential enhancers of protective capabilities and for the optimization of Kevlar® armor design. To assess the possible shear thickening properties and potential application in ballistic protection, ten formulations were developed by employing polyethylene glycol (PEG) or polypropylene glycol (PPG), along with fumed silica or Aerosil HDK®. Rheological characterization facilitated the identification of formulations displaying shear thickening behavior. The potential integration of the selected shear thickening fluids (STFs) into Kevlar®-based composites was investigated by studying the impact resistance of Kevlar® soft armor structures. Also, high-velocity impact testing revealed that the distance between aramid layers plays a crucial role in the impact resistance effectiveness of Kevlar®–STF composite structures and that there is a very narrow domain between optimal and undesired scenarios in which STF could facilitate the penetration of Kevlar. The introduction of STF between the Kevlar sheets disrupted this packing and the energy absorption capacity of the material was not improved. Only one formulation (PEG400, Aerosil 27 wt.%) led to a less profound traumatic imprint and stopped the bullet when it was placed between layers no.1 and no.2 from a total of 11 layers of Kevlar XP. These experimental findings align with the modeling and simulation of Kevlar®–STF composites using Ansys simulation software (Ansys® AutoDyn 2022 R2). [ABSTRACT FROM AUTHOR]

Intensive research is currently being carried out worldwide to replace fossil raw materials with renewable ones or waste based on chemical synthesis. However, it is important that the newly developed raw materials do not conflict with global food production and recommend the use of non-edible or waste raw materials. Therefore, modified non-edible oilseed radish oil was used in the synthesis of polymeric materials. The functionalization of the oil was achieved through one-step, solvent-free transesterification process with triethanolamine, diethylene glycol, polypropylene glycol, ethylene glycol and propylene glycol. Biopolyols with hydroxyl numbers in the range of 237–346 mg KOH/g and different chemical structures were obtained. Open-cell polyurethane foams were produced by replacing 100% of the original petrochemical polyol with the biopolyols. The influence of the chemical structures of the biopolyols on the properties of the thermal insulation materials was analysed. The foams were characterised by low apparent densities of about 16 kg/m3. The type of biopolyol did not have a significant influence on the mechanical strength of the foams. A thermal analysis of the polyurethane biofoams was also carried out. [ABSTRACT FROM AUTHOR]

This research investigates the nano-titanium oxides (TiO2), impact on the composition, nano-indenter test, and mechanical characteristics of Polypropylene (PP). The incorporation of TiO2 nanoparticles into a solution of PP polymer led to the creation of a homogeneous blend. Hydraulic pressing yields a polymer nanocomposite rectangular sheet of 2 millimetres in thickness. In order to examine the nanocomposites, XRD (X-ray diffraction) and FTIR (Fourier transform infrared spectroscopy) were used. The dispersion of the nanoparticles was analysed using a field emission scanning electron microscope (FESEM). The addition of TiO2 nanoparticles at concentrations of 2 and 4 wt% was used to modify polypropylene, while the proportion of polypropylene remained constant at 1% weight. X-ray and FTIR analysis confirmed the existence of TiO2, whereas the SEM findings demonstrated the effective distribution of TiO2 throughout the PP matrix. An investigation was conducted to examine the impact of TiO2 on the mechanical characteristics of PP. The samples were subjected to mechanical characterizations utilising traditional methods such as flexural strength, tensile strength, impact resistance, and nanoindentation. The mechanical investigation revealed that the nano hardness of the changed coating, as measured by nanoindentation, exhibited a maximum increase of 36.9% in comparison to the unmodified coatings. The nanocomposites exhibited enhanced mechanical characteristics, with the nano hardness and elastic modulus of the nanocomposite samples surpassing those of pure PP. [ABSTRACT FROM AUTHOR]

In this study, a series of crosslinked waterborne polyurethane/acrylate copolymer latexes with different compositions were fabricated via emulsion polymerization using oil-soluble initiator (AIBN) based on a solvent-/emulsifiers-free method. Using the blend of styrene (St), butyl acrylate (BA) and crosslinkers (pentaerythritol triacrylate (PET3A) and pentaerythritol tetraacrylate (PET4A)) instead of acetone as a diluent and modifier, polyurethane prepolymers terminated with hydroxyethyl acrylate composite emulsions were prepared using polypropylene glycol (PPG), toluene diisocyanate (TDI), 2,2-dihydroxymethylpropionic acid (DMPA) and diethylene glycol (DEG) without other solvents. It was found that for all the emulsion polymerization of waterborne polyurethane and acrylates initiated by AIBN, the monomer conversions exceeded 96% when the concentration of AIBN was in the range of 0.5% to 0.9% (w/w) and the optimal reaction temperature was 75 °C. The introduction of St, BA and crosslinkers would form the polymer network, improving the tensile strength, water absorption of the copolymer latex films. Dynamic light scattering analyses showed that the copolymer latexes exhibited a unimodal distribution and showed no precipitates and unstable aggregates. The average particle size distribution was in the range of 131–154 nm. Transmission electron microscopy studies have confirmed the similar results and the latex particles possessed the core–shell morphology structure. [ABSTRACT FROM AUTHOR]

Chitosan nanoparticles (CS-NPs) are currently under investigation for a wide range of applications in nanomedicine. We investigated the structural, morphological, and molecular properties of CS-NPs synthesized via ionic gelation and designed specifically for drug delivery. The CS-NPs were prepared at concentrations ranging from 0.25 to 1.0% w/v. The 1.0% w/v CS-NPs were also functionalized with polyethylene oxide (PEO) alone and with a diblock copolymer of PEO and polypropylene glycol (PPG). The average nanoparticle size determined from TEM imaging is in the 11.3 to 14.8 nm range. The XRD and TEM analyses reveal a semi-crystalline structure with a degree of crystallinity dependent upon the nature of CS-NP functionalization. Functionalizing with PEO had no effect, whereas functionalizing with PEO-PPG resulted in a significant increase in the crystallinity of the 1.0% w/v CS-NPs. Additionally, the CS/TPP concentration (CS:TPP fixed at a 1:1 ratio) did not impact the degree of crystallinity of the CS-NPs. FTIR analysis confirmed the incorporation of TPP with CS and an increase in hydrogen bonding in more crystalline CS-NPs. [ABSTRACT FROM AUTHOR]

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of the substance 'phosphorous acid, triphenyl ester, polymer with 1,4‐cyclohexanedimethanol and polypropylene glycol, C10–16 alkyl esters', when used as an additive in all types of polyolefins. The substance is a polymer containing ≤ 13% w/w of a low molecular weight fraction (LMWF, < 1000 Da). A polyethylene sample with 0.15% w/w of the substance was used in a comprehensive set of migration tests with food simulants. The specific migration was up to 0.014 and 0.023 mg/kg in 4% acetic acid and 10% ethanol, respectively. Migration into olive oil was estimated by the Panel to be up to 5.3 mg/kg under worst‐case conditions of use. The migrating LMWF species were comprehensively identified. Those without phosphorous were either without alerts for genotoxicity or listed in Regulation (EU) 10/2011 with worst‐case migrations well below their respective specific migration limits. Toxicological studies were performed using phosphite and phosphate versions of the substance enriched in its LMWF. The substance does not raise a concern for genotoxicity. From a repeated dose 90‐day oral toxicity study in rats with a 50:50 phosphite:phosphate blend, the Panel identified a NOAEL of 250 mg/kg bw per day for each component of the blend. No delayed neurotoxicity in hens was observed. The CEP Panel concluded that the substance does not raise a safety concern for the consumer if its LMWF is not higher than 13% w/w, if it is used at up to 0.15% w/w in polyolefin materials and articles intended for contact with all food types, except for infant formula and human milk, for long‐term storage at room temperature and below, after hot‐fill and/or heating up to 100°C for up to 2 h, and if its migration does not exceed 5 mg/kg food. [ABSTRACT FROM AUTHOR]

Tobacco smoking remains one of the leading causes of premature death worldwide. Electronic Nicotine Delivery Systems (ENDSs) are proposed as a tool for smoking cessation. In the last few years, a growing number of different types of ENDSs were launched onto the market. Despite the manufacturing differences, ENDSs can be classified as "liquid e-cigarettes" (e-cigs) equipped with an atomizer that vaporizes a liquid composed of vegetable glycerin (VG), polypropylene glycol (PG), and nicotine, with the possible addition of flavorings; otherwise, the "heated tobacco products" (HTPs) heat tobacco sticks through contact with an electronic heating metal element. The presence of some metals in the heating systems, as well as in solder joints, involves the possibility that heavy metal ions can move from these components to the liquid, or they can be adsorbed into the tobacco stick from the heating blade in the case of HTPs. Recent evidence has indicated the presence of heavy metals in the refill liquids and in the mainstream such as arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), copper (Cu), and lead (Pb). The present review discusses the toxicological aspects associated with the exposition of heavy metals by consumption from ENDSs, focusing on metal carcinogenesis risk. [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG), polypropylene glycol (PPG), and poly(ethylene glycol‐co‐propylene glycol) (PEPG) of number average molar masses (Mn) of 6–20 kDa are used as macroinitiators in the ring‐opening polymerization (ROP) of l‐lactide to synthesize high molar mass (50 kDa < MnCopo < 120 kDa) PLLA‐b‐polyether‐b‐PLLA linear triblock and starblock copolymers. At the studied block lengths, PEG and PEPG blocks exhibit miscibility with the PLLA blocks in the amorphous domains leading to a plasticization effect. As the PEG or PEPG block content is increased to 18 %wt, the Tg (Tg ≈ 24 °C) and the elastic modulus (E ≈ 500 MPa) are reduced, while the elongation at break (εb ≈ 280%) and crystallization rate are increased. At the same time, small angle oscillatory shear (SAOS) rheometric measurements show that the plasticized copolymers have a reduced melt viscosity. In contrast, SAOS and DSC measurements of the PPG‐containing block copolymers reveal phase separation of the PPG and PLA blocks leading to microstructures in the melt. Tensile tests show that the phase‐separated PPG‐containing block copolymers are more ductile than PLA homopolymers, but more brittle than the PEG‐ or PEPG‐plasticized block copolymers. [ABSTRACT FROM AUTHOR]

Polymeric photocrosslinked networks, of particular interest in the design of materials with targeted characteristics, can be easily prepared by grafting light-sensitive moieties, such as methacrylates, on polymeric chains and, after photochemical reactions, provide materials with multiple applications via photopolymerization. In this work, photopolymerizable urethane–methacrylate sequences were attached to free hydroxyl units of cellulose acetate chains in various proportions (functionalization degree from 5 to 100%) to study the properties of the resulting macromolecules and the influence of the cellulosic material structure on the double bond conversion degree. Additionally, to manipulate the properties of the photocured systems, the methacrylate-functionalized cellulose acetate derivatives were mixed with low molecular weight dimethacrylate derivatives (containing castor oil and polypropylene glycol flexible chains), and the influence of UV-curable composition on the photopolymerization parameters being studied. The achieved data reveal that the addition of dimethacrylate comonomers augmented the polymerization rates and conversion degrees, leading to polymer networks with various microstructures. [ABSTRACT FROM AUTHOR]

One of the most important challenges in the pharmaceutical industry is to produce crystals with desired size and shape distributions, to enhance the critical quality attributes of the drug product, such as efficacy, and to improve manufacturability during downstream processing, such as filtration, drying and granulation. The paper provides a framework for effective crystal shape and size tuning, based on a systematic exploration of standard techniques, such as the linear cooling and supersaturation control (SSC), and novel methods based on the systematic combination of several techniques, namely direct nucleation control (DNC), wet milling, SSC and shape modification additives. The crystallization of lovastatin, which is notorious for its challenging needle-shaped crystals, with an extremely high aspect ratio, was used as a case study, and polypropylene glycol (PPG-4000), at different concentrations, was used as an effective shape modifier from small-scale tests studied previously. The proposed techniques were implemented in the case of seeded and unseeded systems. It was demonstrated that the combination of temperature cycling and polymer additive enhances greatly the control over the aspect ratio and crystal size distribution, compared to conventional linear cooling and SSC strategies. The implementation of wet milling at the beginning of the process, or the introduction of seeds, enhances even further the control of the critical quality attributes of the crystalline product. [Display omitted] • Developed and validated a new framework for systematic crystal shape and size tuning. • Standard cooling crystallization with a polymer additive was insufficient to improve the aspect ratio of lovastatin. • Crystal shape successfully modified using additives and Direct Nucleation Control (DNC). • The additive caused inhibition along the longest axis which resulted in an effective control of the aspect ratio. • The lowest aspect ratio was achieved using a combination of seeding, milling, additives and DNC. [ABSTRACT FROM AUTHOR]

BACKGROUND: The present work provides diagrams for water‐free two‐phase systems based on polypropylene glycol 2000 (PPG 2000) + [C2mim][OAc] + alcohols (primary: methanol, ethanol, 1‐propanol and 1‐butanol; secondary: 2‐propanol and 2‐butanol; and tertiary: 2‐methyl‐2‐propanol) at 298.15 ± 1.00 K and 0.10 ± 0.01 MPa. As a proof of concept, the systems were applied to study the selective partitioning of vitamins, namely β‐carotene and α‐tocopherol. RESULTS: The hydrophilic/hydrophobic balance is the driving force for phase separation. The more hydrophilic alcohols are responsible for the wider biphasic area, and branching increases hydrophilicity and the biphasic area compared to linear alcohols. Additionally, it was verified that the mathematical determination of the tie‐lines satisfactorily describes the positioning in the phase diagram when compared with the analytical determination. In the proposed systems, pure biomolecules partitioned selectively: α‐tocopherol migrated to the PPG 2000 phase (top phase) while β‐carotene to the [C2mim][OAc] phase (bottom phase). For the study with real biomolecules, solid–liquid extraction was performed using 1‐butanol (more selective alcohol) in a solid–liquid ratio of 1:10 at 200 rpm for 60 min. The partitioning trend followed the behavior of systems using pure biomolecules. The highest selectivity (5.3) was observed for the system composed of PPG 2000 + [C2mim][OAc] + 1‐butanol or 2‐butanol. The partition system did not impair the antioxidant potential expressed as DPPH inhibition. CONCLUSIONS: Water‐free two‐phase systems can be formed and applied to partitioning vitamins from tomatoes. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

A polypropylene glycol–polytetrahydrofuran–polypropylene glycol (TPPG) triblock copolymer with Mw of 2330 g mol−1 was synthesized with ring-opening polymerization of propylene oxide using polytetrahydrofuran (1000 g mol−1) as a macroinitiator. The obtained product is characterized by 1H and 13C-NMR spectroscopy, FT-IR, and gel permeation chromatography (GPC). The thermal behavior of the triblock copolymer was investigated by differential scanning calorimetry (DSC). Effective parameters for synthesis such as catalyst type, reaction temperature, reaction time, and solvent type have been studied. The optimized synthesis conditions were as follows: BF3·OEt2 as a catalyst and dichloromethane as a solvent, reaction time 20 h and temperature 0–5 °C. The copolyurethane elastomers were prepared by various NCO/OH ratios using isophorone isocyanate (IPDI) and N100, dibutyltin dilaurate (DBTL) and trimethylol propane (TMP). The elastomer prepared with the mixing curing system (30:70) of (N100/IPDI), 0.5% of DBTL and 0.4% of TMP showed excellent mechanical properties with 1.41 MPa and 163% elongation. [ABSTRACT FROM AUTHOR]

In this work, ladder‐like polyphenylsiloxane containing silanol groups was used for modification of polyurethane (PU) based on MDI and polypropylene oxide polyol. The obtained coatings have excellent mechanical performance and adhesion to steel. This improvement was confirmed through a combination of characterization techniques. The tensile strength and strength adhesion to steel increase by more than one order of magnitude when polysiloxane fraction increased from 10 to 50 wt.%. With an increase loading level, the coating transforms from hydrophilic to hydrophobic. The reinforcement effect was motivated by restriction of molecular mobility in PU matrix as was shown by solid‐state 1H NMR spectroscopy and formation of chemical bonds between PU and polysiloxane units. [ABSTRACT FROM AUTHOR]

Regenerated silk fibroin is a promising bio‐material because of its sustainability, biocompatibility, degradability, and eco‐friendliness. However, silk fibroin hydrogel's intrinsic hard and brittle mechanical properties hinder its application on human skin as a wearable sensor. We used polypropylene glycol (PPG) as a plasticizer to physically blend with a silk fibroin solution, and designed a set of green and environmentally friendly preparation methods without organic solvents to obtain the hydrogel for wearable sensors. PPG molecules will aggregate into clusters to act as a plasticizer. Meanwhile, a large number of hydrogen bonds are formed between the hydroxyl groups in PPG and silk fibroin molecular chains. When the hydrogel is stretched, the hydrogen bond in the silk fibroin chain will release heat in an irreversible form to increase the toughness. The PPG/silk fibroin hydrogel exhibits mechanical strength of 16.6 MPa, breaking elongation of 160%, and toughness of 17.7 MJ/m3. The Ca2+ introduced during the sample preparation process gives the hydrogel ionic conductivity, which provides the possibility of using the hydrogel as a human skin sensing material. [ABSTRACT FROM AUTHOR]

Bio-polyols (BPOs), characterized by a hydroxyl number up to around 90 mg KOH/g, narrow polydispersity index and relatively low molecular mass up to 2000 g/mol, were synthetized from partially and completely epoxidized soybean and linseed oils and caprylic acid or 3-phenyl butyric acid. These BPOs were used in the presence of toluene diisocyanate to produce polyurethane (PU) foams by using a quasi-prepolymer method involving a two-step reaction. A detailed structural investigation of the prepolymers from toluene diisocyanate and both BPOs and polypropylene glycol was conducted by SEC and solution NMR. The apparent density of the foams was in the range of 40–90 kg/m3, with higher values for foams from the aromatic acid. All the foams showed an open-cell structure with uniform and regular shape and uniform size. The specific Young's moduli and compression deflection values suggest superior mechanical properties than the reference foams. The novel synthesized polyurethanes are excellent candidates to partially replace petroleum-based materials. [ABSTRACT FROM AUTHOR]

Double metal cyanide (DMC) catalysts have no alternatives for use in the industrial process of propylene oxide (PO) polymerization to obtain polypropylene oxide (PPO) with the properties required for specialty applications: low degree of unsaturation, high molecular mass, and high hydroxyl value. The modern commercial samples show high performance and allow the process to be performed with extremely low catalyst amounts (down to 25 ppm). Such amounts do not require the catalyst regeneration and to not impair the polymer properties. The main drawbacks of these materials are relatively complex synthesis and moisture sensitivity. Despite the fact that DMC catalysts are known since the 1960s, their hybrid character and variable composition still complicate their study and elucidation of the relationship between the preparation procedure, composition, and properties of these materials. This review is aimed at systematizing and analyzing the information on the synthesis, structure, and action mechanism of DMC catalysts. Both traditional synthesis and nontraditional methods for preparing DMC catalysts are described in detail. Much attention is paid to the catalytic site structure, polymerization mechanism, and physicochemical properties of these materials as heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

When exposed to the open air, the wood can change its physical and structural properties due to the combined effect of ultraviolet radiation, oxygen, humidity, atmospheric pollutants, and microorganisms. The demand for durable coatings with application to wooden structures or pieces is always a relevant topic. Waterborne polyurethane (WPU) dispersions as wood protective coatings might be attractive, especially outdoors. In this work, WPU dispersions have been synthesized from isophorone diisocyanate and different ratios of polypropylene glycol and polycarbonate (PC) diol. Synthesized polyurethanes were applied to wood surfaces as a coating. The results showed that the partial and total replacement of polypropylene glycol (PPG) by PC influences the mechanical, thermal, and structural properties of the films obtained from aqueous polyurethane dispersions. In addition, a simple and promising methodology based on Fourier‐transform infrared (FTIR) spectra was proposed to determine the polycarbonate content in poly(carbonate‐ether‐urethane). The synthesized coatings reduced water absorption by the wood, especially the one with a 25:75 polycarbonate to PPG ratio. The applied coating does not impact the final color of the wood, allowing a natural aging effect. Polyurethanes are promising for use as coatings for wood. [ABSTRACT FROM AUTHOR]

Recent studies in the flotation of fine particles have necessitated new techniques and analyses for developing various strategies. Particularly, the improvements in flotation chemistry including the selection of the type of frother, collector, and other reagents have become very significant. In this study, the effect of different commercial polypropylene glycol frothers (PPG200, 400, and 600) in the presence of dodecylammonium hydrochloride (DAH) was investigated for their contribution to flotation recoveries and bubble–particle attachment time values of fine quartz minerals. Zeta potential measurements with DAH were also carried out as a function of pH and reagent concentration to justify the effect of collector usage alone on the charge of particles. A linear increase in flotation recoveries against collector concentration, e.g., 7.4% recovery at 1 × 10−5 mol/L DAH and 65.4% recovery at 1 × 10−3 mol/L DAH, was obtained. In this context, the contribution of frothers was particularly important in that a recovery of 15.91% in the absence of the frother and a modest increase to 19.70% was obtained upon the addition of PPG600 at its critical coalescence concentration (CCC) of 3 ppm. Finally, a strong correlation was found between the bubble–particle attachment time and flotation recovery as a function of collector concentration (lowest attachment time vs. highest flotation recovery). The latter correlation is very promising because bubble attachment time leads to various micro-mechanisms in flotation including bubble film thinning, bubble rupture, and induction time, and consequently, frother efficiency in the presence and absence of a collector. As a result, the experimental findings were gathered to achieve a consistent base for further fundamental studies on the application of the synergistic effect of frothers and collectors in the flotation of fine particles. [ABSTRACT FROM AUTHOR]

A new hydroxy-silane coupling agent was synthesized from 3-butene-1-alcohol and mercaptopropyl-3-methoxysilane based on a click reaction between double bonds and sulfhydryl groups and was successfully used in the synthesis of silane-modified polyether (STPE). The effect of molecular weight of polypropylene glycol (PPG) on the properties of silane-modified polyether was studied. It was found that with the increase in PPG molecular weight, the initial thermal decomposition temperature and hardness of STPE elastomers decreased, but the molecular structure hardly changed. In addition, with the increase in molecular weight, the elongation at break of the elastomer will gradually increase, but the tensile strength of the elastomer does not change much. When the molecular weight reaches 20 000 g/mol, the resin with a viscosity of 1.6 × 105 mPa s can be obtained, and the elongation at break of the cured elastomer reaches 383.4% and the tensile strength is 0.25 MPa. After the STPE resin was prepared into a silane modified sealant, the tensile strength reached 1.31 MPa and the elongation at break reached 406.2%, which had the best mechanical properties among the prepared sealants. This shows that the sealant prepared from high molecular weight resin has stronger mechanical properties, which provides a new idea for the preparation of sealants. [ABSTRACT FROM AUTHOR]

In this work, the possibility of preparation of copolymers of three-dimensional crosslinked structure based on polypropylene glycol fumarate and acrylic acid is shown. The initial reagent polypropylene glycol fumarate has been synthesized by polycondensation reaction of fumaric acid and propylene glycol. The curing process of polypropylene glycol fumarate and acrylic acid at various mole concentrations was studied using DSC method at isothermal and dynamic regimens. Curing in isothermal condition was carried out at temperatures of 60 °C, 70 °C, and 80 °C. Residual reactivity was evaluated at a dynamic regimen within the temperature range from 30 °C to 200 °C at a constant heating rate. On the basis of calorimetric studies, the thermal effects and kinetic parameters of the reaction (conversion, reaction rate, activation energy) have been determined. Thermal behavior of cured samples of p-PGF-AA was estimated using dynamic thermogravimetry (TGA). According to TGA data, the process of decomposition of the studied copolymers proceeds in several stages. Based on the results obtained, the activation energies of thermal decomposition were calculated using the iso-conversional methods of Kissinger–Akakhira–Sunose and Friedman. [ABSTRACT FROM AUTHOR]

Polypropylene glycol (PPG) is one of the most utilized polymers in aqueous biphasic systems. The low polarity of the polymer-rich phase restricts the application of the ABSs. The applicability of polymer rich ABSs can be induced by adding little amount of ionic liquids as adjuvants. Therefore, an analysis involving the introduction of a small amount of imidazolium-based ILs to PPG 725 + ammonium salts ABSs was performed. The phase diagrams as well as the partitioning behavior of dyes: Orange II (OII), Eriochrome Black T (EBT) and Brilliant Green (BG) were investigated. The addition of 5% 1-butyl-3-methylimidazolium acetate, [BMIM][AC] modulates the partition behaviors of all the investigated dyes. The employed ILs and dyes partitioned preferentially into the polymer-rich phase. The partition coefficients (Kdye) for all the dyes follow the sequence: BG > EBT > OII in all investigated ABSs. The results obtained are in accordance with the logarithm of octanolwater partition coefficients (log Kow) of the respective dyes. The recovery of BG dye from polymer phase has been studied successfully by adsorption onto chitosan. [ABSTRACT FROM AUTHOR]

A silicone-modified waterborne polyurethane emulsion (Si-WPU) was prepared by carbon dioxide binary alcohol (PPC), polypropylene glycol, poly-1,4-butylene adipate glycol, 4-methyl-m-phenylene diisocyanate, 2,2-bis(hydroxymethyl)propionic acid, N- [3-(trimethoxysilyl)propyl] ethylenediamine (KH 792) and triethylamine as the main raw materials. The influence of R(the mole ratio of isocyanate to hydroxyl group), the type and content of soft chain segment as well as the amount of KH 792 on the appearance, particle size and stability of Si-WPU emulsion were studied. The influence of mechanical strength, adhesion, water absorption, water contact angle and heat resistance of the cured Si-WPU film was also systematically studied. The results showed that when R was 1. 67, PPC was the soft-chain segment with an addition volume of 75wt%, and KH 792 was 3. 5wt%, Si-WPU emulsion was pan-blue with low viscosity, low particle size and good stability, i. e., the viscosity was 313 mPa·s and particle size was 213 nm. In addition, the Si-WPU film showed better comprehensive performance, with hardness of 2 H, tensile strength of 53. 83 MPa, fracture elongation of 1 465%, adhesion grade of 4B, water contact angle of 93. 5° and water absorption rate of 2. 65%. A novel preparation route has been provided for high-performance and environmentally friendly waterborne polyurethane coating. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CAPE (caffeic acid phenethyl ester) incorporated microspheres formulate and evaluate these microspheres for topical application. In order to achieve the objective firstly various batches of CAPE loaded microspheres were formulated using varying concentrations of ethyl cellulose as the polymeric matrix and solvent evaporation method. All the microsphere formulations were characterized for yield, entrapment efficiency, In-vitro drug release particle size and FTIR studies were also performed to confirm the non-interference of the drug and excipients. The maximum drug release of CAPE over a period of 12 h was obtained in F2 with 71.02 ± 0.64 % drug concentration found in the dissolution medium whereas the minimum release was witnessed for F5 with 56.89 ± 0.47 drug concentration. The formulation F2 was found to be the most appropriate microspheric formulation loaded with CAPE with good yield, drug encapsulation as well as in vitro drug release. It was therefore considered for formulation in the form of gel. All formulation was achieved employing 22 factorial approaches using both the polymer (carbopol 934) and polypropylene glycol at two concentration levels. All formulations loaded with F2 were found to be white and transparent with good homogeneity with pH ranging from 4.92 to 6.1 confirming that the formulations will be compatible to the skin for topical application. On the basis of the results obtained from the study it can be concluded that Carbopol 934 1% w/v and propylene glycol 20% w/v form an excellent combination for development of gel loaded with microsphere of CAPE. [ABSTRACT FROM AUTHOR]

Water‐dispersible polyurethanes are a greener alternative to polyurethane solutions in organic solvents. Various polyurethane materials were prepared by a two‐step polymerization procedure of polypropylene glycol with Mn of 2000, polyethylene glycol with Mn of 1500, and diisocyanates with different chemical structures, aliphatic, cycloaliphatic and aromatic. It was investigated how the diisocyanate structure affected the molecular morphology, contact angle measurements, and physical characteristics of water‐dispersible polyurethanes. FTIR and NMR measurements showed a close relationship between the intermolecular connections and the hard segment structure, mainly of the diisocyanate used. Also, the polarized light method showed that the presence of the PEG in the hard domain improved aggregation through physical interactions due to its structural flexibility and mobility. These water‐dispersible polyurethanes can assure the use of these polyurethane materials in a broad range of applications with increased environmental protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The common insecticide used in Cabbage and Basmati rice fields is Cartap hydrochloride (CHC). It is a low toxicity insecticide belongs to Neurotoxin. Present study aimed to synthesize a new Nano-insecticide by using polypropylene glycol (PPG) as an encapsulated agent. Nano-CHC is useful for plant disease control. Polypropylene glycol encapsulated CHC size distribution was obtained by PadeLaplace dispersion in the size range in between 60-67nm. The functional group analysis of encapsulated CHC was carried by FT-IR spectroscopy. The structural topology of encapsulated CHC was obtained by scanning electron microscope. The morphological internal structural elucidation of encapsulated CHC can be obtained by transmission electron microscope analysis. The bioactivity study was conducted and shows good efficacy results against Aspergillus flavus, Sclerotium rolfsii and Rhizoctonia solani. [ABSTRACT FROM AUTHOR]

The application of mesenchymal stem cells (MSC) in bone tissue regeneration can have unpredictable results due to the low survival of cells in the process since the lack of oxygen and nutrients promotes metabolic stress. Therefore, in this work, polymeric membranes formed by organic–inorganic hybrid materials called ureasil-polyether for modified glucose release were developed in order to overcome the problems posed by a of lack of this nutrient. Thus, membranes formed by polymeric blend of polypropylene oxide (PPO4000) and polyethylene oxide (PEO500) with 6% glucose incorporation were developed. Physical–chemical characterization techniques were performed, as well as tests that evaluated thermal properties, bioactivity, swelling, and release in SBF solution. The results of the swelling test showed an increase in membrane mass correlated with an increase in the concentration of ureasil-PEO500 in the polymeric blends. The membranes showed adequate resistance when subjected to the application of a high compression force (15 N). X-ray diffraction (XRD) evidenced peaks corresponding to orthorhombic crystalline organization, but the absence of glucose-related peaks showed characteristics of the amorphous regions of hybrid materials, likely due to solubilization. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses showed that the thermal events attributed to glucose and hybrid materials were similar to that seen in the literature, however when glucose was incorporated into the PEO500, an increase in rigidity occurs. In PPO400, and in the blends of both materials, there was a slight decrease in Tg values. The smaller contact angle for the ureasil-PEO500 membrane revealed the more hydrophilic character of the material compared to other membranes. The membranes showed bioactivity and hemocompatibility in vitro. The in vitro release test revealed that it is possible to control the release rate of glucose and the kinetic analysis revealed a release mechanism characteristic of anomalous transport kinetics. Thus, we can conclude that ureasil-polyether membranes have great potential to be used as a glucose release system, and their future application has the potential to optimize the bone regeneration process. [ABSTRACT FROM AUTHOR]

Flexible batteries based on gel electrolytes with high safety are promising power solutions for wearable electronics but suffer from vulnerable electrode‐electrolyte interfaces especially upon complex deformations, leading to irreversible capacity loss or even battery collapse. Here, a supramolecular sol‐gel transition electrolyte (SGTE) that can dynamically accommodate deformations and repair electrode‐electrolyte interfaces through its controllable rewetting at low temperatures is designed. Mediated by the micellization of polypropylene oxide blocks in Pluronic and host‐guest interactions between α‐cyclodextrin (α‐CD) and polyethylene oxide blocks, the high ionic conductivity and compatibility with various salts of SGTE afford resettable electrode‐electrolyte interfaces and thus constructions of a series of highly durable, flexible aqueous zinc batteries. The design of this novel gel electrolyte provides new insights for the development of flexible batteries. [ABSTRACT FROM AUTHOR]

The development of bio‐based polymer materials, such as polylactic acid (PLA) ‐based polymers, is an effective strategy to reduce dependence on petrochemical‐based polymers. However, the preparation of bio‐based polymers with high barrier properties is a major challenge. To overcome this challenge, a nacreous layer structure with a ' brick and mud ' pattern is mimicked to improve the overall performance of the material. In this paper, Poly (L‐lactic acid) (PLLA) and Polypropylene Glycol (PPG) was combined to prepare bio‐based polyurethane (PU‐PLLA), which is used as the slurry structure of nacreous layer. The bio‐based biomimetic composite membrane (PU‐PLLA/BN) is then obtained by adding boron nitride (BN, brick structure of pearl layer) to it. The water vapor permeability test results show that the permeability of PU‐PLLA material can be reduced by more than 50% by 5 wt.% BN, which is because the addition of BN can increase the length and tortuosity of the gas molecular diffusion path in the composite. Therefore, this pearl‐inspired PU‐PLLA/BN film has excellent moisture resistance, which opens up a broad road for the practical application of PLLA in flexible laminated packaging. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess in vitro bioactivity of novel remineralizing dental composites loaded with calcium phosphate fillers and chlorhexidine in polypropylene glycol (PPG) resin matrix. Methods: The stock monomer was prepared by adding 69.75% urethane dimethacrylate and 23.25% of the polypropylene glycol dimethacrylate with silica fillers, chlorhexidine (5 wt%), and varying levels of calcium phosphate fillers. The study groups were BC (basic composite), commercial control, CHX-CP5, CHX-CP10, and CHX-CP15, respectively. Bioactivity was assessed by placing samples in the simulated body fluid (SBF) for 7, 14, and 28 days and observed under the scanning electron microscope and energy dispersive X-ray spectroscopy. Data were presented in mean and percentage with a 95% confidence interval. Intergroup analysis was performed using one-way ANOVA and the p-value was set ≤0.05. Results: The SEM images showed the deposition of calcium phosphate on the surface of CHX-CP10 and CHX-CP15 after 28 days in SBF. Mineral deposits of calcium and phosphate were observed on the surface of the experimental formulation containing higher calcium phosphate fillers (CP10 and CP15) in EDX. Conclusion: The addition of calcium phosphate fillers to the composites resulted in an apatite layer formed and demonstrated enhanced bioactivity in the presence of PPGDMA and CHX. [ABSTRACT FROM AUTHOR]

Several high solid content waterborne polyurethane dispersions (WPUDs) with the combination of anionic and nonionic stabilization were synthesized by polyaddition reaction using isophorone diisocyanate (IPDI), trimethylol propane (TMP) and 1,6-hexanediol (HDO) as the hard segments, polypropylene glycol with molecular weight of 2000 Da (PPG-2000), and polytetramethylene ether glycol with molecular weight of 2000 Da (PTMG-2000) as the soft segments, anionic diol dimethylol propionic acid (DMPA) and nonionic diol Y-mer N 120 (NID) as the donors of hydrophilic groups. The chain extension reaction between residual NCO groups was made by using hydrazine (HYD). The effects of the combination of anionic and nonionic monomer and macrodiol types on the performance of the WPUDs were studied in terms of particle size distribution and dispersion stability. The results showed that the WPUDs exhibited narrow particle size distribution, good appearance and good mechanical properties. [ABSTRACT FROM AUTHOR]

In this report, epoxy resin (EP) composites prepared using polypropylene (PP) and graphene oxide (GO) as additives in varying percentages are reported. Around 21 types of composites were prepared by dispersing polypropylene in 5–35%, or graphene oxide in 5–35%, with 95–65% of epoxy resin. Also, a ternary composite of EP matrix was prepared by adding 1:1 ratio of both PP & GO (5–35%) in 95–5% through a melt condensation technique. The graphene oxide platelets used in the study were obtained through modified Hummers method. The particle size and its structural characteristics were evolved through FESEM & XRD studies. The mechanical aspects of composites were tested by following standard ASTM procedures. The failed portions of the composites were examined through FESEM; it revealed a fiber/thread like structure, which promotes the higher tensile strength, Young's modulus, etc. In contrast to the plain epoxy resin, the composites display remarkable mechanical properties. Especially, the epoxy resin (80%) blended with 10% PP and 10% GO displays higher tensile strength (22.5 MPa,) tensile modulus (4.56 GPa,) flexural strength (75 MPa), and so on. All these data are very much useful, if these composites are used in the manufacturing of components like space shuttle, engine cover, heaters, brake pad, cryogenic fuel tank, etc. in engineering applications. [ABSTRACT FROM AUTHOR]

This study developed a scalable and straightforward adaptation methodology for melt processing of polypropylene (PP) to provide a high degree of exfoliation of multilayer graphene oxide (GO) by using a high‐shear mixer. GO was first produced by an improved and eco‐friendly electrochemical exfoliation by using an environmentally friendly aqueous methanesulfonic acid (MSA) and a sodium sulfate salt system to minimize the environmental impact. The produced GOs then were melt blended with PP and their mechanical, thermal, and morphological properties were investigated under different GO loadings to attain ideal configuration and increase interfacial interactions between polymer matrix and reinforcer. Comparisons were made by producing different PP composites using two different GO types produced in salt and acid environments. Additionally, by applying different voltages to salt system, the effect of applied voltage on the properties of both GO material and the composites were discussed. The characterization results indicated that GO obtained in MSA solution caused a 71% increase in flexural modulus and 46% in flexural strength with the addition of 1 wt% GO. The rheological characterization also showed that dispersion and viscosity improved with lower GO loadings compared to neat polymer by providing cost‐effective and scalable graphene manufacturing. [ABSTRACT FROM AUTHOR]