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Background: The aim of this study was to present our new technique of immediate breast reconstruction with prepectoral Polyuretane (PU) Implants, covered with an autologous dermo-adipose flap, in skin-reducing mastectomy both for risk-reducing (prophylactic mastectomy) and therapeutic cases. Methods: We performed a single-center, retrospective review of 21 patients (mean age 47 years), undergone skin-reducing mastectomy and immediate breast reconstruction with prepectoral Polyuretane (PU) Implants, covered with an autologous dermo-adipose flap, un the period January 2018–June 2021. All procedures were performed by the same surgeon. Results: A total of 36 skin-reducing mastectomies (6 curative, 15 prophylactic) with one-stage prepectoral PU foam-coated implant and autologous dermo-adipose flap reconstruction were performed. All postoperative complications were collected. Quality of life (QoL) and satisfaction with reconstruction were evaluated through the BREAST-Q questionnaire, administered preoperatively and at 12 months after surgery. Independent Student's t tests were used to compare means of continuous variables and Chi-square test was used for ordinal variables. A p-value ≤0.05 was considered statistically significant. Uni- and multiple linear regression analyses were used to confirm all results. Out of 21 patients, we observed one small wound dehiscence and one partial Nipple-Areola Complex (NAC) necrosis. All cases of minor complications were managed conservatively and did not affect the quality of the final outcome. No implant loss was observed. No significant severe capsular contracture (grade III or IV) was detected at follow-up. Overall satisfaction with breasts, psychosocial, physical and sexual well-being all significantly increased, analyzing BRAST-Q data. Statistical analysis showed a significant influence of diabetes on the risk of complications. Conclusions: Our experience suggests that the procedure described is effective, feasible and cost-effective. It is easier to perform compared to similar and more demanding procedure, reduces operative time, and minimizes complications related to manipulation of the pectoralis major muscle, while also contributing to the containment of costs. Moreover, it appears to be oncologically safe, provides good esthetic results with low postoperative complication rate and leads to high level of patients' satisfaction. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

With isophorone diisocyanate and polytetrahydrofuran as basic raw materials, dimethylolpropionic acid and 2,3‐dihydroxypropanesulfonic acid triethylamine salt (DHPSTEA) as chain extension agents, trimethylolpropane as crosslinking agent, N, N‐dimethylethanolamine as neutralizer, the high‐solid carboxylate/sulfonate waterborne polyurethane (SC‐HWPU) was synthesized. The effect of COO−/SO3− molar ratio on the properties of SC‐HWPU was studied. Fourier transform infrared and x‐ray photoelectron spectroscopy results demonstrated that the SC‐HWPU molecular chain contained carboxylate and sulfonate groups. The results of thermogravimetric analysis, dynamic mechanical analysis, and mechanical properties of SC‐HWPU film indicated that higher DHPSTEA content was favorable for the thermostability and mechanical properties when the total dosage of hydrophilic groups was invariable. When the mole ratio of COO−/SO3− is 8:2, the solid content of the prepared SC‐HWPU3 emulsion can reach to 51.6%, which has excellent storage stability and alkali resistance stability. Subsequently, the application of SC‐HWPU emulsion on the fixed‐island type polyamide/polyethylene terephthalate copolymer superfine fiber non‐woven fabric single‐coating process was analyzed, and the water‐base superfine fiber non‐woven fabric was prepared. Scanning electron microscopy showed that there was still a large amount of SC‐HWPU filled in the superfine fiber gap after alkali‐decrement, indicating that SC‐HWPU has excellent alkali resistance. [ABSTRACT FROM AUTHOR]

It remains enormous challenges to balance the conflict between high strength and toughness mechanical properties and excellent room‐temperature self‐healing abilities of polyurethane elastomers. In this work, we report a recyclable room‐temperature self‐healing polyurethane elastomer with excellent mechanical properties. The prepared polyurethane elastomer (PU‐DA‐Zn0.50) exhibits high tensile strength of 15.33 MPa, high toughness of 76.77 MJ m−3, and high elongation at break of 1604.46% by introducing isophorone diamine (IPDA), 1‐(3‐aminopropyl) imidazole (IMZ) and zinc ions into polymer system to form a dynamic double‐cross‐linked structure (hydrogen bonds and Zn2+‐imidazole coordination bonds). In addition, the tensile strength of fractured polyurethane can reach more than 80% of the original sample after 48 h of self‐healing at room temperature without external stimuli, which is attributed to the kinetics of rapid exchange of Zn2+‐imidazole coordination bonds at room temperature. It is worth noting that the balance between excellent mechanical properties and outstanding room‐temperature self‐healing ability can be optimized by adjusting the Zn2+‐imidazole coordination bond density in the system. Moreover, the dynamic nature of the double‐cross‐linking network endows polyurethane with favorable recyclability. The above remarkable comprehensive performances reveal a great potential of PU‐DA‐Znx elastomer in the fields of wearable flexible electronic devices such as bionic skin, human motion monitoring, and soft robots. [ABSTRACT FROM AUTHOR]

The motivation behind this work is the preparation of polyurethane-magnesium aluminum layered double hydroxide (PU-LDH) nanocomposite and its application as a coating for steel protection. The coating was prepared with different doses of LDH, ranging from 0 to 2% of the coating weight. The effect of different concentrations on the mechanical, adhesion, and surface properties of PU coating is studied. Firstly, LDH was prepared via the coprecipitation process and then distributed in PU matrix. The nanocomposites were then crosslinked in the form of coating layers on steel. The preparation of the thermally stable crystalline LDH nanoparticles with 89 nm particle size was confirmed by FTIR, XRD, DLS, and TGA. SEM photos showed the dispersed and intercalated structure. The coating characteristics demonstrate that addition of LDH decreased the drying time and increased the dry film thickness of PU up to 1.5% due to the crosslinking between the large surface area nanofiller and polyurethane matrix. Furthermore, the prepared LDH nanofiller increased the adhesion strength, impact resistance, abrasion resistance, modulus, and flexibility of PU due to the strong polymeric network structure. The 2% nanocomposite coating shows poor properties due to the excess concentration and heterogeneous dispersion of nanoparticles within the PU polymer. The resistance to fire and some chemicals was supported by the thermally and physically stable LDH nanoclay. The former characterizations state that the proposed PU-LDH nanocomposite is an enhanced and applicable coating. [ABSTRACT FROM AUTHOR]

The implementation of hot melt adhesives reaching structural adhesion with both impact resistance and detachability is of prospective industry value but still remains challenging. In this work, 2‐amino‐4‐hydroxy‐6‐methylpyrimidine serving as both chain extender and end‐capping reagent due to its isomerism, was developed to construct a supramolecular polyurethane‐derived hot melt structural adhesive. The as‐synthesized PUM elastomers occurs obvious decrease of molecular weight at 80°C compared to room temperature, revealing the existence of self‐complementary 2‐ureido‐4[1H]‐pyrimidinone (UPy) motifs at chain ends. This unique structure allows to chemically incorporate abundant hierarchical and quadruple hydrogen bonding moieties, which results in remarkable enhancement of shear strength, ranging from 6.4 to 16.6 MPa. More importantly, it also exhibits unique impact‐strengthening and reproducible adhering ability. The Hopkinson‐press‐bar and cyclic tensile tests manifest that quadruple hydrogen bonds play a pivotal role in buffering external forces and increasing energy dissipation when exposed to high velocity impacts. The true stress and strain synchronously increase as the strain rate augments while the shear strength can even roar up to ~18 MPa at high tensile speed. With regard to mild synthetic conditions, atomic economic use of reactants, it is promising that this material has industrial potential to be utilized in applications referred to energy‐absorption and reproducible structural adhesion. [ABSTRACT FROM AUTHOR]

Understanding how dangling fragments of polyurethanes (PU) affect its microphase separation structure and damping properties can provide insights for designing desired materials at the molecular scale. By varying the types of diol extenders (such as 1,2‐ethyleneglycol, 1,2‐propanediol, and 1,2‐butanediol), PU samples with different dangling residues were successfully synthesized. Using atomic force microscopy and small‐angle x‐ray scattering, we confirmed that the introduction of dangling chains disrupts microphase separation and demonstrated a correlation between the degree of suppressed microphase separation and the size of the dangling residues. Fourier transform infrared spectroscopy and molecular dynamics simulations confirmed that dangling chains reduce the hydrogen bonding index while increasing the phase compatibility between soft and hard segments. Differential scanning calorimetry (DSC) measurements revealed an increased glass transition temperature (Tg), indicating hindered movement of backbone segments due to dangling chains. Moreover, lengthening the dangling chains further decreased Tg. Dynamic mechanical analysis (DMA) demonstrated improved damping properties with the introduction of dangling chains, although increasing chain length led to deteriorating damping properties, consistent with observations from DSC. These findings suggest that the variations in macroscopic properties of PU induced by dangling chains are linked to hydrogen bonding interactions and micromorphology at the molecular level. [ABSTRACT FROM AUTHOR]

In order to obtain a kind of anticancer drug delivery carriers with good stability in blood circulation, high cellular uptake, and controlled drug release ability, folate‐modified polyurethane with disulfide bonds and amino groups (FPUSN) and polyurethane with carboxyl groups (PUC) were respectively synthesized. FPUSN and PUC could co‐assemble in water to form nanomicelles (FPUSN/PUC) via electrostatic interaction. When the mass ratio of FPUSN to PUC was 12, FPUSN/PUC‐12 micelles had obvious negative‐to‐positive charge‐reversal property with decreasing pH from 7.4 to 5.0. Doxorubicin‐loaded micelles (FPUSN/PUC‐12@DOX) with negative charges showed excellent stability under simulated normal physiological condition. However, the charge‐reversal happened at pH 6.5 and positive charges increased with the pH decrease. When the glutathione concentration was 10 mM, the structure of FPUSN/PUC‐12@DOX micelles was broken. So FPUSN/PUC‐12@DOX micelles exhibited significant acid/reduction‐sensitive drug release properties and then DOX could be rapidly released in simulated tumor intracellular environment. Cellular experimental results demonstrated that FPUSN/PUC‐12 micelles could enhance cellular uptake under acid condition and FPUSN/PUC‐12@DOX micelles had better anti‐proliferation effect against HGC‐27 cells at pH 6.5 than that at pH 7.4 owing to multi‐responsive synergistic effects. Therefore, FPUSN/PUC micelles will have great application potential as drug delivery carriers for enhancing anticancer efficacy. [ABSTRACT FROM AUTHOR]

Efficient and stable blue fluorescent materials are the key components of light‐emitting devices and have received wide attention. Herein, transition metal complexes Zn(5‐AQ)2, Cu(5‐AQ)2, and Cd(5‐AQ)2 are prepared by using 5‐aminoquinoline (5‐AQ) as ligand and Zn2+, Cu2+, and Cd2+ as the central ions, respectively. Then, waterborne polyurethane (WPU)‐based transition metal complexes Zn(5‐AQ)2‐WPU, Cu(5‐AQ)2‐WPU, and Cd(5‐AQ)2‐WPU with different emission wavelengths of blue fluorescence are prepared by bonding Zn(5‐AQ)2, Cu(5‐AQ)2, and Cd(5‐AQ)2 to polyurethane chains as chain extenders, respectively. Noteworthily, with the increase of transition metal ion radius (Zn2+ < Cu2+ < Cd2+), the fluorescence emission wavelengths of the complexes showed different degrees of blue‐shift, and the blue‐shifted wavelengths showed a decreasing trend. Importantly, their fluorescence colors are blue‐shifted from blue‐green to blue with different emission wavelengths after accessing the polyurethane backbone, which has potential applications in the field of tuning white LED materials. The thermal decomposition temperatures of Zn(5‐AQ)2‐WPU, Cu(5‐AQ)2‐WPU, and Cd(5‐AQ)2‐WPU are above 220°C with good thermal stability, and their fluorescence lifetimes are prolonged by 8.817, 8.896, and 6.489 ns, respectively, compared with the complexes. Furthermore, WPU transition metal complexes with water as a dispersive medium have an antibacterial efficiency of up to 100% against Escherichia coli, which is an environmentally friendly antibacterial material with broad application prospects. [ABSTRACT FROM AUTHOR]

Steel slag (SS) as solid waste, has low resource utilization efficiency and seriously endangers environmental safety and human health. To explore the potential utilization value of SS and address the flammability challenge of rigid polyurethane foam (RPUF), with a novel flame‐retardant system composed by SS and dimethyl methyl phosphonate (DMMP) was explored. The DMMP/SS system effectively improved the high temperature stability of the RPUF composites. When the mass ratio of SS and DMMP was 1:1, the limiting oxygen index of RPUF/DMMP/SS reached 23.1 vol% and UL‐94 vertical combustion tests passed V‐2 level. Upon incorporation of 15 wt% DMMP, the initial decomposition temperature (T−5 wt%) reduced to 165.3°C, a decrease of 32.2%, while the Tmax2 and residue yield at 700°C exhibited negligible alteration. The peak heat release rate of RPUF/DMMP/SS composite (118.20 W g−1) was 11.02% lower than that of pure RPUF, indicating the significant enhancement of fire safety of the composites. Results confirmed that a synergistic flame‐retardant mechanism was existed between DMMP and SS in enhancing the fire safety of RPUF composite. Introducing a 20 wt% SS content reduces the ID/IG ratio to 1.85, thereby markedly enhancing its heat resistance. This work provides a new application field of SS and paves a novel approach to enhance fire safety of polymers. [ABSTRACT FROM AUTHOR]

Eco-friendly and highly flame-retardant coatings for cotton fabrics urgently need to develop, but still faces significant challenges including the inadequacy of organic flame retardants, the adverse effects of high-load inorganic flame retardants on cotton fabrics, and the flammability of adhesives. Hence, this study describes a sandwich-like nanocoating for the fabrication of highly flame-retardant cotton fabric. Phytic acid (PA), a bio-based polyacid, was employed to prepare phosphorus-containing waterborne polyurethane (P-WPU) as the flame-retardant adhesive. With the help of multi-metallic layered double hydroxide (CoMnAl-LDH) and PA, six types of sandwich-like nanocoatings were constructed on cotton fabrics. Evaluation of their flame retardancy through vertical burning and cone calorimeter tests revealed that the sandwich-like nanocoating composed of PA as the top layer, P-WPU as the middle layer, and LDH as the bottom layer demonstrated exceptional flame retardancy in cotton fabric. It self-extinguishes within 5 s and the highest LOI value of 31.5% in all fabric samples, representing an increase of 89.76% over the pristine fabric. Meanwhile, the peak heat release rate (PHRR, 82.60 kW/m2) and total heat release (THR, 1.67 MJ/m2) were significantly reduced by 71.65% and 54.74%, respectively, relative to those of the pristine fabric. A synergistic flame-retardant mechanism was proposed that involved multiple barrier effects, catalyzing carbonization, and the release of non-flammable gases. Overall, this work may provide valuable insights for constructing highly flame-retardant cotton fabric, offering potential solutions to solve industry challenges. [ABSTRACT FROM AUTHOR]

With the increasing drilling depth of mines, the cross-complexity of fissures in the rock body, and the frequent occurrence of sudden water surges, polymer slurry, with its advantages of good permeability and strong water plugging, is increasingly used in mine grouting projects. Additional research is needed in order to further improve the grouting performance of polymer slurry, ensure the safety of mining operations, and reduce the grouting cost. In this paper, a polymer composite grouting material was prepared with diphenyl methyl diisocyanate, polyether polyol, and fly ash, as the main raw materials, with coupling agent and catalyst as auxiliary reagents. The performance of the composite grouting material in terms of mechanical properties, thermal stability, hydrophobicity, and bonding was explored. This study's findings indicated that incorporating fly ash led to notable enhancements in the thermal stability and water resistance of the polymer slurry. Furthermore, the introduction of fly ash notably raised the starting degradation temperature of the polymer, boosted the water contact angle of the composite material, and reduced the density and reaction temperature of the composite material. In addition, the catalyst and coupling agent as auxiliary reagents affected the polymers in terms of mechanical properties; in this paper, dibutyltin dilaurate was used as the catalyst, and organosilanes were used as the coupling agent. The catalyst successfully sped up the polymer's gel time, however, an excessive quantity of catalyst compromised the polymer's mechanical characteristics. The addition of organosilanes has a positive effect on the dynamic mechanical properties of the composites, fracture toughness, compression, bending, and bond strength. The research can offer a theoretical direction for creating polymer mixtures in mine grouting projects. [ABSTRACT FROM AUTHOR]

Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface. Conventional slope protection methods for bedding slopes, such as retaining walls, stabilizing piles, and anchors, are time-consuming and labor- and energy-intensive. This study proposes an innovative polymer grout method to improve the bearing capacity and reduce the displacement of bedding slopes. A series of large-scale model tests were carried out to verify the effectiveness of polymer grout in protecting bedding slopes. Specifically, load-displacement relationships and failure patterns were analyzed for different testing slopes with various dosages of polymer. Results show the great potential of polymer grout in improving bearing capacity, reducing settlement, and protecting slopes from being crushed under shearing. The polymer-treated slopes remained structurally intact, while the untreated slope exhibited considerable damage when subjected to loads surpassing the bearing capacity. It is also found that polymer-cemented soils concentrate around the injection pipe, forming a fan-shaped sheet-like structure. This study proves the improvement of polymer grouting for bedding slope treatment and will contribute to the development of a fast method to protect bedding slopes from landslides. [ABSTRACT FROM AUTHOR]

High internal phase emulsions (HIPEs) are commonly stabilized by a large amount of surfactants that should be removed after the polymerization of the continuous phase, and the resulting polyHIPEs from W/O HIPEs are usually brittle and chalky. Herein we report on an amphiphilic polymerizable polyurethane (PPU) macromolecular surfactant synthesized by polyaddition reaction of diisocyanates and polyols, which can well stabilize up to 88% internal phase volume of W/O HIPE with a content of only 5 wt% based the oil phase. Compared with the HIPEs stabilized by traditional surfactant Span 80, HIPEs stabilized by PPU at either room temperature or 70 °C are much more stable owing to the increased viscosity which can inhibit droplet coalescence. Moreover, the resulting polyHIPEs not only have several times higher mechanical properties than those stabilized by Span 80 but also have higher elasticity. The effects of concentration of PPU on the morphology and mechanical properties of the resulting polyHIPEs were investigated. It was found that with the increase of PPU content, the average void and window sizes decreased, while the compression strength increased. Cyclic compression tests were performed to examine reversible compressibility and durability of these polyHIPEs. The polymerizable polyurethane macromolecular surfactant (PPU) synthesized through the polyaddition reaction of diisocyanates and polyols can solely stabilize high internal phase emulsions (HIPEs), and highly interconnected macroporous polymer produced by the polymerization of HIPE stabilized with PPU, known as polyHIPE, can withstand large deformation compression with no visible cracks. [ABSTRACT FROM AUTHOR]

The preparation of rigid polyurethane foam with uniform pore size is extremely challenging. In this work, double‐effect baking powder was used as foaming agent, and rigid polyurethane foam with regular morphology was successfully prepared through semi‐prepolymerization. The rigid polyurethane foam apertures with regular morphology were controlled by the secondary release of CO2 when the content of baking powder is 0.30 part. Combined with theoretical calculation and experimental test, it is found that the particle size distribution, wall thickness, and hole shape are uniform, regular, thin, polygonal, and few broken holes. The compression strength, contact angle, and surface energy of the rigid polyurethane foam are 33.36 kPa, 109.6°, and 21.8 mJ/m2 after adding 0.20 part of double‐effect baking powder, respectively. By adjusting the amount of double‐acting baking powder, the porosity, mechanical properties and foam rate of the polyurethane foams could be significantly improved. Due to the molecular solvation effect, rigid polyurethane foams will deform in the water and oil due phase, but it can remain stable for a long time at room temperature without solvent. It provides a new method for the preparation of rigid polyurethane foam, which is expected to be widely used in transportation and other fields. Highlights: Baking powder was firstly used as a foaming modifier for rigid polyurethane.Baking powder releases CO2 twice to ensure uniform structure of polyurethane cell.Rigid polyurethane foam has long‐term stability and regular, uniform cell holes.The porosity and mechanical properties of foams could be significantly improved.Foaming mechanism of rigid polyurethane using baking powder was firstly revealed. [ABSTRACT FROM AUTHOR]

There is an increasing demand for superhydrophobic surfaces due to their unique properties like self-cleaning, anti-icing, corrosion resistance, etc. The development of polyurethane (PU)-based superhydrophobic coating has garnered significant attention for aircraft applications. Polyurethane (PU) topcoat is widely used in aircraft and is hydrophilic in nature with a water contact angle (WCA) of 75 ± 3°. In the present work, a hydrophilic PU clear coat on aircraft-grade aluminum substrate is transformed to a superhydrophobic (SHP) surface by spraying environmentally friendly hydrophobically modified silica nanoparticles (HSiNps) oonto a PU layer that was partially cured in a hot air oven at 60°C for 1.5 h. The SHP surface exhibited a WCA of 162 ± 3° and a sliding angle (SA) of 8 ± 3°. With the incorporation of HSiNps, micro – nano dual-scale surface roughness is created and the surface roughness of the PU coating is increased from 0.35 to 2.42 µm. The coating exhibits good adhesion (5B) with excellent water repelling property and remains thermally stable and superhydrophobic even after subjecting it to 100°C for one week. Durability of the coatings is studied by immersing the coatings in various liquids. The retention of superhydrophobic property after anti-fogging, water sprinkler, and sand paper abrasion tests further demonstrate the robustness of the coating. Polyurethane-based SHP coating is prepared using hydrophobized silica nanoparticles. Partially cured polyurethane coating help in grafting of silica nanoparticles on to the surface. The coatings are durable to heat, solvents, corrosive liquids and sand paper abrasion [ABSTRACT FROM AUTHOR]

A self‐healing anticorrosion protective was developed for steel st‐37 exposed to the marine tidal zone, which is composed of a multi‐layer polymer coating. The coating includes zinc‐rich epoxy primer, self‐healing microencapsulated embedded epoxy, and a top coat consisting of polyurethane incorporated with silica nanoparticles. The size of microcapsules decreased with increasing agitation during encapsulation, which varies from 4 to 43 µm. Good performance was observed for producing the encapsulated particles with a size of up to 5 µm and more than 90% loading of the embedded healing agent, in which a 1680 rpm agitation along with a pH of 3 for the synthesis environment and a 130 min for the synthesis duration is set. The optimal amount of microcapsules and silica nanoparticles was 10 and 1.5 wt%, respectively. Also, the promised self‐healing anticorrosion coating leads the damaged areas to be fully healed in almost 12 h in the face of harsh conditions. In contrast to the non‐self‐healing one, the healing ability of the developed self‐healing coating shows good barrier properties and leads to a lesser loss of interface adhesion. [ABSTRACT FROM AUTHOR]

Due to its excellent durability and steady mechanical qualities, three‐dimensional porous polyurethane foam (PUF) presents a wide range of possibilities for flexible piezoresistive sensors. Its extreme flammability, poor electrical conductivity, and susceptibility to outside factors present serious difficulties, though. In this study, a waterborne polyurethane‐coated flexible PUF sensor that incorporates reduced graphene oxide (RGO) and polyaniline (PANI) through a methodical, step‐by‐step dip‐coating methodology is successfully developed. The final product has a water contact angle of 133°, which improves its ability to adapt to a variety of environmental circumstances. Flexible graphene sheets are incorporated to improve heat resistance and flame retardancy, and PANI and RGO provide strong bonding to the PUF framework, ensuring outstanding structural stability even after 1500 cycles. The flexible foam sensor shows promise for use in flexible piezoresistive sensors and electronic skin due to its remarkable strain monitoring range of up to 70%, quick response time of 0.39 s in sensitivity experiments, and adaptability to different physical activities like walking and gesturing. [ABSTRACT FROM AUTHOR]

In this work, FR‐PNX, an alkylphosphate oligomer was introduced into rigid polyurethane foam (RPUF) to fabricate FR‐PNX/RPUF composites. The flame retardancy, thermal stability, and combustion properties of composites were investigated by limiting oxygen index (LOI), thermogravimetric (TG), microcalorimetry (MCC), scanning electron microscopy (SEM), et al. The flame retardancy tests demonstrated that the incorporation of 50 phr of FR‐PNX yielded composites that the highest LOI of 23.6 vol% and achieved a V‐0 rating in the UL‐94 test. TG results indicated that FR‐PNX promoted the decomposition of FR‐RPUF in the process, but enhanced the high‐temperature stability of the composites. MCC analyses revealed that the addition of FR‐PNX suppressed the heat release during combustion, and FR‐PNX50/RPUF exhibited the lowest total heat release of 17.3 MJ/m2, a 35% reduction compared to the pure sample. Moreover, the peak heat release rate was decreased to 83.1 W/g, representing a 46.9% reduction compared to pure RPUF. SEM and Raman analyses of the char residue demonstrated that the incorporation of FR‐PNX facilitated the formation of a dense and continuous char layer in the FR‐RPUF, with increased graphitization degree of the char layer, thereby enhancing the composite's fire resistance through the development of a more stable fire barrier. [ABSTRACT FROM AUTHOR]

A green method to synthesize self‐matting waterborne polyurethane acrylic hybrid emulsion with hydrophobic function is introduced in this study. A reactive waterborne polyurethane (RWPU) dispersion containing unsaturated CC double bonds was prepared from epoxidized soybean oil. Subsequently, the RWPU dispersion was copolymerized with fluorinated monomers of different carbon chain lengths to prepare polyurethane acrylic hybrid emulsion (PUF). The results revealed the gloss levels of PUF films to be as low as 12.4 gloss units at 60°. The morphology of PUF films was observed by scanning electron microscope and three‐dimensional surface profilometer, and the relationship between surface roughness and gloss was discussed in detail. In addition, thermal gravimetric analysis was conducted to determine the thermal stability of the PUF films, and the results denoted that these PUF films exhibited excellent thermal stability. Comprehensive performance tests indicated that the RWPU dispersion, which was copolymerized with hexafluorobutyl methacrylate at a weight of 10%, exhibited a low gloss, a high contact angle of 120°, and a high elongation percentage of 423%. Furthermore, the dynamic light scattering results showed small average particle size, revealing the excellent storage stabilities. [ABSTRACT FROM AUTHOR]

Isocyanate‐based monomers and polymers have found widespread industrial application; however, the realization of green water‐based products via the preparation of stable isocyanate aqueous emulsions remains challenging. Herein, a series of organosilicon and organofluorine synergistically modified amphiphilic branched polyurethanes (HBWPU), synthesized by grafting perfluorohexyl ethanol semi‐terminated isophorone diisocyanate (IPDI) onto a hydrophilic polyurethane prepolymer, is presented. Subsequently, using a physical mixing method, stable diisocyanate emulsions are fabricated by preparing diisocyanate latex particles with IPDI as the core and hyperbranched water‐based polyurethanes (HBWPU) as the shell. Structural investigations showed that the branching degree and fluorine content of the HBWPU significantly affects the stability of the diisocyanate emulsions. Increasing the degree of branching from 0.34 to 0.86 causes the amount of residual isocyanate (NCO) groups to decrease from 20.1% to 16.7%. In contrast, an increase in the fluorine content from 0% to 17.8% increases the amount of residual NCO groups from 11.5% to 24.6%. Thus, HBWPU can be used as an emulsifier to prepare waterborne diisocyanate cross‐linking agents. Such polyurethane‐coated isocyanate aqueous emulsions can increase the hardness and significantly improve the acetone resistance of hydroxyl polyacrylate resins. [ABSTRACT FROM AUTHOR]

Polyurethane-based thin-film composites (PUR-based TFCs) with different carbon fillers, namely, carbon flocs formed by carbon dots (CDs) containing O, N, and F heteroatoms and carbon nanotubes (CNTs), were prepared by hot pressing. The morphology and composition of the carbon fillers were investigated by SEM/EDX. Temperature-programmed desorption mass spectrometry and thermogravimetric analysis revealed that the CNTs have the highest thermostability among the fillers. Microwave studies in the X-band showed that the PUR-based TFCs with the CNTs were characterized by higher reflection losses and lower transmission losses than the PUR-based TFCs with the flocs formed by the studied CDs. [ABSTRACT FROM AUTHOR]

The corrosion resistance of cement–water-glass dual-liquid slurry is poor. Improving its material properties is necessary. In this study, we examined the influence of water-based lotions on the fluidity, gelling time, and mechanical properties of a cement–water-glass dual-liquid slurry based on the mix proportion of the dual-liquid slurry commonly used in construction. The mixture ratio of a C-S (cement–water-glass slurry) dual-liquid slurry was adjusted by introducing a waterborne polyurethane lotion and a waterborne acrylic lotion to modify the traditional C-S dual-liquid slurry material. When acrylic acid is used as a modifying polymer at a dosage of 7.5%, the flowability and gelation time of the dual-liquid slurry are excellent, the compressive strength of the stone body decreases slightly, the flexural strength is improved to a certain extent, and the stone body's crack resistance during water loss is also enhanced. Moreover, the porosity of the stone body is low. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) coatings are used in diverse applications such as textile coating. Up to today, landfilling is still the most occurring way of processing PU waste. Biodegradation is an alternative route for processing PU waste and decreases the amount of microplastics in the case of landfilling. In this study, a biodegradable PU textile coating was developed. The PU was characterized via Fourier-transformed infrared (FT-IR) thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The PU was thermoplastic and had a melting point of approximately 33 °C. The performance of the coating was studied by assessing the water barrier and mechanical properties. The PU coating completely disintegrated, and the biodegradation of PU was assessed in soil and was almost 60%. Furthermore, the plant toxicity was examined by evaluating seedling emergence and growth. [ABSTRACT FROM AUTHOR]

With rapid advances in electronic and communication technology, electromagnetic interference and other problems are becoming increasingly prominent. Thus, electromagnetic interference shielding materials have recently garnered extensive attention. In this study, a multi‐walled carbon nanotube/polyurethane/non‐woven electromagnetic shielding material (CPNW) is developed using impregnation and nonsolvent‐induced‐phase separation techniques. Utilizing a three‐dimensional nonwoven network as the substrate, the "nonwoven fabric‐polyurethane‐carbon nanotube" composite is impregnated and cured via the non‐solvent‐induced‐phase separation method, resulting in a distinctive porous dual‐network structure that ensures robust interfacial bonding between carbon nanotubes, nonwoven fabric, and polyurethane. At a carbon nanotube content of 10% (based on the mass of nonwoven fabric), CPNW exhibited an electromagnetic interference shielding effectiveness of 28.8 dB, a thermal conductivity of 0.127 W m−1 K−1, and a burning time of 1 min and 15 s, demonstrating outstanding electromagnetic shielding, flame retardant, and infrared stealth capabilities. Overall, this study laid a theoretical groundwork for the development of multifunctional non‐woven electromagnetic shielding materials with widespread application potential in aerospace, military, artificial intelligence, and wearable electronics. [ABSTRACT FROM AUTHOR]

This study examines the efficacy of icephobic polyurethane nanocomposite coatings in mitigating corrosion on an aluminum substrate. A titanium-based conversion coating is applied to modify the substrate, and the research focuses on optimizing the dual functionalities of icephobicity and anticorrosion within the polyurethane coatings while ensuring strong substrate adhesion. The coatings are formulated using fluoropolyol, isocyanate, and silica nanoparticles treated with polydimethylsiloxane. Surface properties are analyzed using contact angles, contact angle hysteresis measurements, and atomic force microscopy, and the coatings' icephobicity is evaluated through differential scanning calorimetry, freezing time delay, ice adhesion under impact and non-impact conditions, and ice accretion tests. The corrosion resistance and adhesive strength of the coatings are assessed using electrochemical impedance spectroscopy and cross-cut tests, respectively. Increasing the concentration of silica nanoparticles to 10 wt.% increases contact angles to 167°, although the 4 wt.% coating produces the lowest contact angle hysteresis (3° ± 0.5°) and ice nucleation temperature (−23 °C). The latter coating is then applied to a substrate pretreated with a titanium/cerium-based conversion coating. This prepared surface maintains an ice adhesion of about 15 kPa after 15 icing/de-icing cycles and provides approximately 90 days of surface protection (|Z|lf = 1.6 × 109 Ω·cm2). Notably, the impedance value exceeds that of untreated substrates, underscoring the effectiveness of the titanium/cerium-based conversion coating in enhancing both corrosion resistance and coating adhesion to the substrate. [ABSTRACT FROM AUTHOR]

A UV‐ and thermo‐responsive polyurethane‐acrylate prepolymer was synthesized from palm olein (POo) via a non‐isocyanate route. The process included epoxidation of POo, carbonation of epoxidized palm olein (EPOo) into polycyclic carbonate in a solvent‐free and mild condition (100°C, 1 atm), followed by reacting with ethylene diamine and acrylic acid. The chemical structure of the non‐isocyanate polyurethane‐acrylate (NIPUA) prepolymer was elucidated by 1H and 13C nuclear magnetic resonance (NMR) and Fourier transform‐infrared spectroscopy (FTIR), while weight average molecular weight of NIPUA was determined by gel permeation chromatography (GPC). The NIPUA (0–20 wt%) was incorporated with thermoplastic elastomer (TPE) as a plasticizer and cured under UV light and thermal stimulations. The cured NIPUA/TPE films were characterized by FTIR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile strength test. Under UV and thermal stimulations, the NIPUA/TPE demonstrated enhanced tensile properties (elongation at break >1280%, Young's modulus ~25 MPa), thermal properties (lower Tg), lower water contact angle, and shortened curing time as compared with the blank TPE. The 20 wt% NIPUA/TPE films exhibited susceptibility to enzymatic biodegradation and noncytotoxic to HEK 293 cells in vitro, demonstrated it's potential as a UV‐ and thermo‐responsive plasticizer for TPE in manufacturing of medical devices. [ABSTRACT FROM AUTHOR]

In this study, we investigate the fabrication of ambient room temperature responsive shape memory polyurethane (SMPU)‐coated fabric using a simple dip coating method, aiming to enhance the shape memory response of smart textiles. Two SMPU were synthesized using different chain extender 1,4 butanediol (BDO‐SMPU) and polyethylenimine (PEI‐SMPU). Critical parameters such as SMPU concentration, dwell time, and coating solution temperature are optimized to ensure exceptional shape memory performance while also maintaining the fabric's handle, comfort, and durability. We determined that PEI‐SMPU/Cotton fabric exhibits superior memory performance, with a 90.2% shape recovery at a 1% PEI‐SMPU concentration. Conversely, BDO‐SMPU fabric demonstrated a 75.8% shape recovery under different conditions (10% SMPU concentration, 50°C solution temperature). Furthermore, shape recovery is influenced by programming temperature and load; at 35°C and 10 N load, PEI‐SMPU/Cotton significantly outperforms BDO‐SMPU/Cotton, showing about 20% improvement in shape recovery. This study indicates that modifying SMPU from BDO‐SMPU to PEI‐SMPU can notably enhance shape recovery performance at 35°C, marking a significant advancement in human body temperature responsive smart fabric technology. [ABSTRACT FROM AUTHOR]

The utilization of leather waste (LW) in a polyurethane (PU) matrix makes a smart and novel shape stable phase change material (SSPCM). This is essential for sustainability as it reduces landfill waste after use. The PU is synthesized in bulk with a 90% yield, using biodegradable polycaprolactone diol and bio‐based polyol (castor oil), along with tolylene‐2,4‐diisocyanate. PL and PLG composites are prepared by blending of constituent components PU (P), LW (L), and poly(glycidyl methacrylate) (PGMA, G), as specified by their code names. Role of LW (hydrogen bonding and chemical crosslinking) and morphology are elucidated by FTIR and SEM, respectively. Self‐healing time (2 h), shape fixity ratios (Rf) (PL: 60–80% and PLG: 60–70%) and shape recovery ratios (Rr) (100% for both) are determined at 60°C. PLG displays faster shape recovery in water (<30 s) compared to air (>300 s). Shape stability and thermal properties of the SSPCM are examined using the temperature responsive leakage study, TGA, and DSC. This research introduces a new approach for using leather waste (LW) in SSPCM, with self‐healing and 100% Rr. This material may find application where SSPCM with high durability and flexibility is essential such as textile and footwear materials. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department 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.)

In this study, carbon-carbon double bonds and catechol groups modified oligochitosan (OCS)/photocurable polyurethane composite films (OPU) were prepared for wound dressing application. Methacrylic anhydride (MA) was used to modify oligochitosan. The effect of the ratio of amino groups on OCS to MA on the properties of the composite films was investigated. The results showed that the OPU films possessed the best overall performance in hydrophilicity, mechanical strength, adhesion properties, and antibacterial activity when the ratio of amino groups on OCS to MA was 4:2. The prepared films may show potential application as wound dressings. [ABSTRACT FROM AUTHOR]

Sandwich-structures are widely used in structural application for their damping nature, attributed by its viscoelastic or honeycomb core. However, the geometry and material variety of the honeycomb core greatly influence the structural dynamics. Previous works don't deals with the sandwiched plates with composite face sheets and diverse core (different materials and geometry) in a single study; which is attributed for better understanding; in this work. Theoretically, the outer-layers considered to be carbon-fiber-epoxy composite, while multiple cases of core material (epoxy, polystyrene and polyurethane) is assumed. The material properties of outer layer is calculated by mixture-rule. The equivalent porosity factor is introduced in the material model to calculate the material properties of the honeycomb core. Further, the equation of motion is derived using third order shear deformation theory and fundamental-frequencies in simple-supported condition are determined for thickness ratio of face to core-layer (hf/hc), shape (circular, triangular, square and hexagonal), and dimension (length and thickness) of honeycomb core to study the effect on the plate dynamics. The results are compared with the findings of Finite-element-analysis (FEA) using ANSYS 16.0. It is observed that the core material, geometry, and hf/hc affects plate stiffness. In addition, increase of unit cell wall length and thickness reduces the porosity and increases plate strength. The triangular core have maximum strength with least porosity contrast to circular structured unit cell. Increasing the thickness of core layers reduces plate stiffness and thus a drop of natural frequency. Further, polyurethane core has greater stiffness than epoxy and polystyrene. [ABSTRACT FROM AUTHOR]

Shape memory polymers have been widely researched to develop multifunctional materials that respond smartly to external stimulations and programmed signals. Among them, shape memory polyurethane (SMPU) is drawing great attention owing to its highly tunable properties and ease of integrating new functions. However, the effect of urea bonds on SMPU elastomers has rarely been investigated because of the extreme reactivity of amine crosslinkers. In this study, we used diethanolamine (DEOA), which contains a secondary amine, as the crosslinker for SMPU synthesis. Unlike other crosslinkers containing primary amines, they can form urea bonds in a more gentle manner. The urea bonds reinforce the intermolecular interactions between the hard segments with strong hydrogen bonding, thus increasing the phase separation and degree of crystallization. Consequently, the urea‐containing SMPU exhibits improved mechanical strength and shape memory abilities for both fixing and recovery. Moreover, the transcarbamoylation reaction, which enables the reconfiguration of the original shape, is observed. The introduction of the urea bonds into the SMPU elastomer can be beneficial in achieving flawless shape memory performances in various sensitive applications. [ABSTRACT FROM AUTHOR]

Flexible electronics are striving in modern society, and they impose harsh and urgent requirements for flexibility on electronic package substrates. However, traditional materials, including ceramics, metals, or polymers are lack of flexibility. Herein, a polyurethane named PU‐D1Q1VF1 is proposed via incorporating carefully selected biobased units and synergistic dynamic bonds, and the PU‐D1Q1VF1 not only meets the basic requirements of flexibility but also possesses properties of self‐heal, UV‐protection, reprocessability, and degradability. The polycaprolactone diol (PCL diol) was employed as the soft segment, and the bis(2‐hydroxyethyl) disulfide (HEDS) and lignin derived model monomer hydroquinone were selected as chain extenders. Moreover, carefully synthesized bio‐based monomer (E)‐4‐(((furan‐2‐ylmethyl)imino)methyl)‐2‐methoxyphenol (VF) was used as the capping agent, which could facilitate the self‐healing process of the PU‐D1Q1VF1. [ABSTRACT FROM AUTHOR]

The primary objective of this research is to fabricate semi‐interpenetrating polymer networks (semi‐IPNs) via in‐situ polymerization of methyl methacrylate (MMA) within a polyurethane (PU) framework. To produce polymethyl methacrylate (PMMA) from MMA in the PU matrix, solution polymerization was utilized in the following weight ratios: 30/70, 50/50, 70/30, and 90/10. The effective formation of semi‐IPNs of PU/PMMA was confirmed by several techniques. Fourier transform infrared (FTIR) proves that no new chemical bonds formed between the semi‐IPNs, and only physical interactions were present, and X‐ray diffraction (XRD) techniques tell about the amorphous nature of these semi‐IPNs. The field emission scanning electron microscope (FESEM) and atomic force microscope (AFM) were utilized to examine the morphology of PU/PMMA semi‐IPNs. In contrast to alternative semi‐IPNs, 70/30 and 90/10 PU/PMMA exhibit a uniform morphology devoid of phase separation. Furthermore, the significant thermal stability and transitions of these semi‐IPNs were assessed using a thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Additionally, the mechanical analysis indicates that among the different percentages of PU/PMMA, 70/30 PU/PMMA exhibits the highest tensile strength of approximately 50.5 MPa. The observed enhancement in mechanical strength can be attributed to interpenetrating networks (IPNs) formed between the constituents. The synthesized PU/PMMA semi‐IPNs have potential in various fields, including medical devices, automotive components, sports, and other advanced applications. [ABSTRACT FROM AUTHOR]

After tooth loss, particularly in the posterior maxilla, the alveolar ridges undergo bone resorption. Therefore, ensuring the appropriate quantity and quality of alveolar bone is crucial for accurate implant positioning and achieving optimal esthetic and functional results. This study aimed to evaluate biomechanical parameters (insertion torque: IT, removal torque: RT, and implant stability quotient: ISQ) of distinct truncated cone implant designs (Sinus-plant and SLC) on polyurethane blocks simulating type D3 and D4 bone. SLC implants exhibited significantly higher IT, RT, and ISQ values compared to Sinus-plant implants, except in the 10 pounds per cubic foot (PCF) density block with a cortical layer for the IT (24.01 ± 0.91 vs. 23.89 ± 1.66 Ncm). The IT values for SLC implants ranged from 13.95 ± 0.19 Ncm in the lowest density block to 37.94 ± 0.45 Ncm in the highest density block, consistently providing significantly higher primary stability with an ISQ of approximately 70 in the highest density block. Despite lower ISQ in the lowest density block (48.60 ± 0.52 and 48.80 ± 0.42 in buccolingual and mesiodistal directions), it was deemed acceptable considering the inadequate bone densities in the maxillary region. These findings on SLC suggest potential clinical advantages, including reduced procedure duration and costs, improved stability, and the possibility of immediate implant placement following sinus augmentation, thereby streamlining the rehabilitation process. [ABSTRACT FROM AUTHOR]

To enhance mechanical, adhesive, and thermal properties of Room Temperature Vulcanized (RTV) silicone rubber, a silicon-containing polyurethane/epoxy resin modifier (ESiPU) was developed. A three-phase system of polyurethane/epoxy resin/silicone rubber was prepared through blending, modification, and co-curing. FT-IR and 1H-NMR were employed to characterize the chemical structure of ESiPU. Microscopic analysis revealed improved compatibility between modified epoxy resin and silicone rubber. Mechanical testing showed significant enhancements in tensile strength, elongation at break, and adhesive strength, with RTV-20phr exhibiting increases of 236, 266, and 259%, respectively. Thermogravimetric analysis indicated higher initial decomposition temperature compared to pure RTV. At the same time, the char residue at 800 °C increased to 8.67%. TG-IR analysis demonstrated ESiPU's ability to delay thermal degradation. Contact angle test confirmed improved hydrophobicity. Overall, the developed silicone rubber system exhibits promising mechanical and thermal properties, suggesting potential for aerospace heat protection applications. [ABSTRACT FROM AUTHOR]

In recent years, there has been considerable focus on ensuring that energy is used in the most efficient manner possible. This is due to the fact that globally, over 70% of energy is generated from fossil fuels. Consequently, the matter of designing and utilizing materials that will negate energy losses within the construction industry is of paramount importance. Simultaneously, the necessity for a sustainable approach to the design and production of materials is strongly emphasized. This paper presents an innovative approach to the use of a combination of mineral and plant-based fillers in polyurethane foam technology as a thermal insulation material with the potential to be used in construction to reduce energy consumption. Polyurethane composites containing fly ash from biomass combustion and the addition of rice, sunflower, and buckwheat husks as plant fillers were proposed. The structure of the obtained materials was studied, and the most important physical properties were analyzed. These included apparent density, dimensional stability, water absorption, and the effects of UV radiation and water influence on the carbon, hydrogen, nitrogen, and oxygen content. Moreover, the mechanical properties of the materials were investigated, including compressive strength and brittleness. Additionally, the foams were subjected to flammability tests using a cone calorimeter. Furthermore, additional parameters were determined, including the limiting oxygen index and the vertical and horizontal flammability tests. The results demonstrate the beneficial effects of combining mineral and vegetable fillers in polyurethane foam. [ABSTRACT FROM AUTHOR]

All artificial materials used for implantation into an organism cause a foreign body reaction. This is an obstacle for a number of medical technologies. In this work, we investigated the effect of high-energy ion bombardment on polyurethane for medical purposes and the reaction of body tissues to its insertion into the mouse organism. An analysis of the cellular response and shell thickness near the implant showed a decrease in the foreign body reaction for implants treated with high-energy ions compared to untreated implants. The decrease in the reaction is associated with the activation of the polyurethane surface due to the formation on the surface layer of condensed aromatic clusters with unbonded valences on the carbon atoms at the edges of such clusters and the covalent attachment of the organism's own proteins to the activated surface of the implant. Thus, immune cells do not identify the implant surface coated with its own proteins as a foreign body. The deactivation of free valences at the edges of aromatic structures due to the storage of the treated implant before surgery reduces surface activity and partially restores the foreign body response. For the greatest effect in eliminating a foreign body reaction, it is recommended to perform the operation immediately after treating the implant with high-energy ions, with minimal contact of the treated surface with any materials. [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 study aims to solve the problem of dynamic crack repair in concrete. Although conventional polyurethane has good strength, its tensile and shear properties are poor. It was found that nano-silicon had an overall enhancing effect on the mechanical properties of polyurethane; therefore, five sets of tests with different dosages (0%, 2%, 5%, 7.5%, and 10%) were designed. The compressive, tensile, and shear mechanical properties of nano-silicon-modified polyurethanes were tested by compression, tensile, and straight shear tests, and the microscopic appearance of the materials was observed by scanning electron microscopy. The results showed that nano-silicon could enhance the mechanical properties of polyurethane. The best filling effect on polyurethane was achieved at a dosage of 5%, which increased the compressive, tensile, and shear strengths by 29.4%, 257.6%, and 202.1%, respectively, compared with the substrate. The compressive and tensile moduli in the small strain range were enhanced by 268.5% and 511.8%, respectively. After exceeding 5%, the mechanical properties of the materials decreased due to the enhanced nanoparticle agglomeration effect, which led to the appearance of voids inside the materials. The comprehensive analysis shows that nano-silicon can better enhance the mechanical properties of polyurethane with an optimal dosage of 5%, which is stronger relative to other repair materials and does not require time maintenance. [ABSTRACT FROM AUTHOR]

Polyurethanes are renowned for their incredible versatility. They are available in various forms, such as foams, thermoplastics, elastomers, and paints. These polymers are synthesized from two chemical substances: isocyanates and polyols. The increasing interest in the utilization of materials from renewable sources has spurred significant research in search of replacements for these two substances. For instance, castor oil can be used as a substitute for polyol, in addition to being an abundant renewable source. In this context, the objective of this study is to investigate how the variables temperature (2 °C, 24 °C, and 70 °C) and mass ratio (2:1, 1:1, and 1:2) influence the final properties of polyurethane foams. The foams were prepared using the one-shot method under controlled agitation. The results indicated that replacing polyol with vegetable oil was successful, as evidenced by the appearance of reference bands in the FTIR spectra. XRD and DSC analyses confirmed the amorphous nature of the polyurethanes, and TG tests demonstrated that a temperature of 70 °C significantly reduced the thermal stability of the foams, especially those based on vegetable sources. However, synthesis temperatures of 2 °C and 24 °C did not show considerable alteration in thermal stability. And the analysis of the effect of the sol fraction variables demonstrated that the polyol/isocyanate ratio has a significant effect, especially in vegetable-based foams. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Silk is the property of Zhejiang Sci-Tech University Magazines 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.)

Until recently, recycling thermoset polyurethanes (PUs) was limited to degrading methods. The development of covalent adaptable networks (CANs), to which PUs can be assigned, has opened novel possibilities for actual recycling. Most efforts in this area have been directed toward inventing new materials that can benefit from CAN theory; presently, little or nothing has been applied to industrially producible materials. In this study, both an industrially available polyol (Sovermol780®) and isocyanate (Tolonate X FLO 100®) with percentages of bioderived components were employed, resulting in a potentially scalable and industrially producible material. The resultant network could be reworked up to three times, maintaining the crosslinked structure without significantly changing the thermal properties. Improvements in mechanical parameters were observed when comparing the pristine material to the material exposed to three rework processes, with gains of roughly 50% in elongation at break and 20% in tensile strength despite a 25% decrease in Young's modulus and crosslink density. Thus, it was demonstrated that theory may be profitably applied even to materials that are not designed including additional bonds but instead rely just on the dynamic urethane bond that is naturally present in the network. [ABSTRACT FROM AUTHOR]

Introduction: Patients in intensive care units (ICUs) frequently lose control over their fecal continence leading to fecal incontinence (FI). We provide an overview of existing medical devices, which are supposed to alleviate FI-related problems. Areas covered: Fecal management systems (FMS) prevent infections and complications. They reduce the risk of pressure ulcers and fecal incontinence. The systems enhance patient comfort and mitigate emotional distress during illness. Furthermore, FMS facilitate nursing care by reducing the incontinence-related workload. Finally, these systems can help minimize treatment costs by preventing complications, and reduction of extended hospital stays and additional treatments. Several well accepted systems made of silicone are on the market. A polyurethane-based soft balloon FMS (hygh-tec® basic-plus) has also been introduced, offering more comfort to the patient, safer handling for the healthcare professionals, and provides reliable leakproof access to the patient's colon. In addition to contamination-free fecal diversion, the trans-anal sealing mechanism of the device also allows for irrigation and delivery of medication into the colon. Expert Opinion: FMS in ICUs are integral to patient care and dignity. Recognizing and prioritizing the importance of these systems is essential for providing the highest standard of care to critically ill patients in the ICU. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid coating has been applied on metallic corrosion protection effectively. Molybdenum disulfide (MoS2) nanosheets with graphene-like two-dimensional lamellar structure were an anticorrosion inorganic additive, rendering the organic coating better corrosion resistant. However, the aggregation and poor solubility are still current issues that should be addressed. Functionalization MoS2 nanosheets with surface modified by polydopamine (PDA) and silane coupling agent (KH560) were prepared in polyurethane (PU) composite coatings to obtain dense and intact multilayer network structure coatings for corrosion protection. KH560-PDA-MoS2/PU coating with crosslinked polymer network structure has a high impedance modulus, large contact angle, and strong hydrophobicity. The coating meets the national technical standards for salt spray testing and nitric acid (HNO3) titration testing, demonstrating excellent corrosion resistance. [ABSTRACT FROM AUTHOR]

High‐energy‐density and cost‐effective lithium‐rich oxides (LRO) are considered as the promising cathode materials for the next‐generation lithium‐ion batteries. Nevertheless, the elevated cut‐off voltage and the complex interface interactions have presented significant challenges that can lead to material degradation. Specifically, the inevitable release of lattice oxygen and the highly reactive interface‐driven irreversible migration of transition metal (TM) ions in LRO make the construction of a robust interface extremely important. Herein, an effective and efficient coating approach is applied to stabilize the interface structure of LRO by introducing a coordination bond between the strong ligand of polyurethane (PU) and the surface of LRO particles. This functional coating stabilizes the crystal field stabilization energies of LRO by acting as a strong ligand in spectrochemistry to form a coordination bond with Mn4+ in Li2MnO3 at high voltage. Consequently, irreversible oxygen release and TM ions migration are greatly inhibited. Overall, the LRO‐PU cathode exhibits superior electrochemical cyclability with a retention of 80.0% at 1C after 300 cycles and enhanced rate capability with a retention of 80.9% at 0.1C after rate cycles, marking a significant step toward commercial implementation. [ABSTRACT FROM AUTHOR]

A highly flexible, tunable morphology membrane with excellent thermal stability and ionic conductivity can endow lithium metal batteries with high power density and reduced dendrite growth. Herein, a porous Polyurethane (PU) membrane with an adjustable morphology was prepared by a simple nonsolvent–induced phase separation technique. The precise control of the final morphology of PU membranes can be achieved through appropriate selection of a nonsolvent, resulting a range of pore structures that vary from finger–like voids to sponge–like pores. The implementation of combinatorial DFT and experimental analysis has revealed that spongy PU porous membranes, especially PU−EtOH, show superior electrolyte wettability (472%), high porosity (75%), good mechanical flexibility, robust thermal dimensional stability (above 170 °C), and elevated ionic conductivity (1.38 mS cm−1) in comparison to the polypropylene (PP) separator. The use of PU−EtOH in Li//Li symmetric cell results in a prolonged lifespan of 800 h, surpasing the longevity of PU or PP cells. Moreover, when subjected to a high rate of 5 C, the LiFePO4/Li half‐cell with a PU−EtOH porous membrane displayed better cycling performance (115.4 mAh g−1) compared to the PP separator (104.4 mAh g−1). Finally, the prepared PU porous membrane exhibits significant potential for improving the efficiency and safety of LMBs. [ABSTRACT FROM AUTHOR]

The water-rich nature of the dentin bonding microenvironment, coupled with the stresses on the bonding interface, contributes to the hydrolytic degradation of the hybrid layer, resulting in a decline in bonding durability and, ultimately, restoration failure. Currently, the 3-step etch-and-rinse technique remains the gold standard for dentin bonding, and the bonding mechanism mainly involves a physical interaction with little chemical bonding. In this study, we have developed a siloxane-modified polyurethane monomer (SPU) with acrylate and siloxane modifications that chemically binds to both collagen and hydroxyapatite in dentin. Formulated as a bisphenol A-glycidyl methacrylate alternative, the SPU monomer-based adhesive was designed to improve dentin bonding quality and durability. Attenuated total reflection Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscope, and hydroxyproline release assays were performed on SPU-treated collagen, hydroxyapatite, and acid-etched dentin slices to dentin. The physicochemical properties of the configured SPU adhesives were profiled for polymerization behavior, water contact angle, and tensile strain and strength. The bonding effectiveness was assessed through micro-tensile strength, nano-leakage tests conducted on the bonded samples before and after thermal cycle aging. Finally, we further conducted in vivo and in vitro experiments to assess the biocompatibility of adhesives. The results showed that the siloxane groups of SPU monomer could covalently bind to dentin collagen and hydroxyapatite. The incorporation of SPU in the adhesive led to a significant increase in adhesive polymerization (P < 0.05) and tensile strain at break up to 134.11%. Furthermore, the SPU adhesive significantly improved dentin bond strength (P < 0.05), reduced interfacial nano-leakage (P < 0.05), and displayed good biocompatibility. In conclusion, the application of SPU, which achieves dual chemical bonding with dentin, can improve the quality of the hybrid layer, buffer the interfacial stresses, enhance the interfacial resistance to hydrolysis, and provide a feasible strategy to extend the service life of adhesive restorations. [ABSTRACT FROM AUTHOR]

Polyurethane foam compositions derived from bioderived polyester polyols with various additives were evaluated for disintegration under composting conditions using the ISO 20200 standard and were characterized by thermogravimetric analysis, microscopy, infrared spectroscopy, and imaging to provide additional insight. Compared to polyether polyol-based polyurethanes, the bioderived polyurethanes were found to display increased disintegration with an average mass loss of 25.4 ± 3.6 weight percent when subjected to composting conditions for 45 days, suggesting that these materials are less likely to persist in the environment when compared to other types of commodity plastics. Additives such as carbon black and lignin added within the foam composition did not accelerate the disintegration. [ABSTRACT FROM AUTHOR]

This study aims to provide a high-value and environmentally friendly method for the application of coal-based solid waste. Modified fly ash/polyurethane (MFA/PU) and modified coal gangue powder/polyurethane (MCG/PU) composites were prepared by adding different contents of MFA and MCG (10%, 20%, 30%, 40%). At the filler content of 30%, the compressive strengths of MFA/PU and MCG/PU are 84.1 MPa and 46.3 MPa, respectively, likely due to an improvement in interface compatibility, as indicated by scanning electron microscopy (SEM). The MFA/PU and MCG/PU composites present their highest limiting oxygen index (LOI) values of 29% and 23.5%, respectively, when their filler content is 30%. MFA has advantages in improving the LOIs of composites. Cone calorimetry (CCT) and SEM demonstrate that the two composites exhibit similar condensed-phase flame-retardant behaviors during combustion, which releases CO2 in advance and accelerates the formation of a dense barrier layer. Compared with the MFA/PU composites, the MCG/PU composites could produce a more stable and dense barrier structure. Water quality tests show that heavy metals do not leak from FA and CG embedded in PU. This work provided a new strategy for the safe and high-value recycling of coal-based solid waste. [ABSTRACT FROM AUTHOR]