Good Mechanical Properties Research Articles

Development of liposomal amniotic mesenchymal stem cell metabolite products (AMSC-MP) loaded-scaffold for in vitro osteogenesis induction

The use of scaffolds with good biocompatibility and mechanical properties largely determines the success of bone defect therapy intended to improve quality-adjusted life years. Furthermore, amniotic mesenchymal stem cell metabolite product (AMSC-MP) is required to accelerate bone regeneration with sustained release required to maximize the effectiveness of therapy. This study aims to evaluate the effect of different phospholipids on the osteogenesis capacity of AMSC-MP liposome loaded into scaffold. The thin layer hydration method was employed to create the AMSC-MP liposomes which had different lipid components: L-α-phosphatidylcholine (PC) an unsaturated or hydrogenated soybean phosphatidylcholine (HSPC), a saturated phospholipid, with different types of charged phospholipids i.e., 1,2-dioleoyltrimethylammoniumpropane (DOTAP) or 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), which were cationic and non-ionic lipids respectively.AMSC-MP liposomes were embedded in the scaffold during a 24-hour incubation period. The results indicated that the particle sizes of liposomes prepared with saturated phospholipids, HS-DOTAP (132.35 ± 2.75 nm) and HS-DOTAP (152.85 ± 5.86 nm) were larger than those with saturated phospholipids, namely PC-DOTAP (139.355 ± 2.75 nm) and PC-DOTAP (91.85 ± 0.07 nm). The use of DOTAP in AMSC-liposomes resulted in positively charged vesicles i.e., +5 mV for HSPC-DOTAP and + 10 mV for PC-DOTAP. Moreover, the results of an MTT viability test conducted on 7f2 cells and MSC indicated that all the formulas demonstrate good in vitro biocompatibility. Formulations containing DOPE produced high cellular uptake values and had superior sustain release properties compared to the others. This result correlates positively with cell attachment to the liposome scaffold which was higher than the others. Moreover, DOPE-containing formulations increased RUNX2 expression, indicating enhanced in vitro osteogenesis capacity. Therefore, Liposome AMSC-MP loaded scaffold demonstrates high potential for use in bone regeneration therapy.

Largely enhanced damping performance of nitrile rubber/ethylene–vinyl acetate blends via phenolic resin-induced phase separation

The low glass transition temperature (Tg) and narrow effective damping temperature range (EDTR) greatly restrict the application of common vulcanized rubbers in fields relating to high temperature environmental condition due to the greatly reduced damping performances. In this work, phenolic resin (PR) was incorporated into nitrile rubber/ethylene–vinyl acetate (NBR/EVM) blends through melt-compounding processing, and the microstructure and damping performance changes induced by PR were comparatively investigated. The results show that PR induces the phase separation of the blends and most of PR particles selectively locate in the NBR component. Molecular dynamics simulation confirms that more hydrogen bonds form in the ternary blends, and reduced free volume fraction is also achieved. The ternary blends show good high-temperature damping performances, and apparently enhanced Tg (up to 17.7 °C) and EDTR (82.6 °C, from −2.6 to 80 °C) are also achieved. Additionally, the ternary blends exhibit good mechanical properties, including higher ductility and larger fracture energy, and better energy dissipation ability. This work provides an alternative resolution way to enhance the damping performances of the common vulcanized rubbers at high temperatures.

Fabrication of Zinc(II) Mediated Poly(Acrylamide Co Acrylic Acid) Hydrogel with Thixotropic and Tribological Properties.

Hydrogels have emerged as promising candidates for biomedical applications, such as replacing natural articular cartilage, owing to their unique viscoelastic properties. However, sufficient mechanical properties, self-healing ability, and adhesive nature are some issues limiting its application window. Here, a facile one-pot synthesis of dual cross-linked zinc-coordinated copolymer hydrogels is presented. The network structure of the copolymer hydrogels is strategically developed via dynamic and reversible physical cross-linking by Zn2+ ions and simultaneous covalent cross-linking through a covalent cross-linker viz methylene bisacrylamide. Fourier-transform infrared (FTIR), X-ray diffraction (XRD) scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) analysis have thoroughly characterized the structure of the synthesized hydrogels. The introduction of Zn2+ offers dynamic and reversible complexation, leading to excellent mechanical properties and self-healing features. Moreover, the percentage of the equilibrium water content of zinc-coordinated copolymer hydrogel samples is comparable with that of natural articular cartilage. The Shear sliding study shows the dominant adhesive behavior of HGel-Zn(NO3)2 sample compared to the parent HGel sample. This facile dual cross-linked hydrogel, HGel-Zn(NO3)2, with a combination of good mechanical properties, efficient self-recovery, adequate water content, and favorable adhesive nature, seems very promising to mimic the articular cartilage.

Formation of Graded TiO2 Layer on Ti Wire by Direct Alternating Current Discharge Plasma at Atmospheric Pressure

Although metallic materials have been used as load-bearing materials in dental and biomedical fields since they have good mechanical properties such as good ductility and strength, their aesthetic properties are inferior to those of ceramic or resin. To obtain aesthetically improved Ti dental devices, the formation of white titanium oxide on pure Ti dental devices was studied. Direct atmospheric pressure plasma (APP) treatment using alternating current was carried out on pure a Ti plate and wire. It was found that a titanium oxide layer with enough whiteness can be obtained on pure Ti wire using direct APP treatment. Although delamination of the titanium oxide layer was found after a bending test, the concept of functionally graded materials (FGMs) can overcome the shortcoming.

Study on the polymerization shrinkage and mechanical-physical properties of dental resin composite modified by polyurethane dimechacrylate and glass flake fillers: Short title: Aging resistance for dental resin composites with low shrinkage

ObjectivesWe intend to explore the polymerization shrinkage and mechanical-physical properties of the dental resin composite modified by polyurethane oligomer PU-MA and glass flakes fillers, and provide some experimental information for developing new dental materials. MethodsBased on Bis-GMA/TEGDMA, the new dental resin composite was hand fabricated by combining PU-MA with different content (65 wt% ∼ 75 wt%) of glass flakes/Si-Al-borosilicate glass mixed fillers. The kinetics of polymerization shrinkage was investigated by using an experimental set-up based on laser triangulation. The mechanical-physical properties of specimens after 60 days water immersion and 5000 times thermo-cycles were measured by three-point bending test and micro vickers hardness tester. Data were submitted to one-way ANOVA/LSD-test (α = 0.05). Independent sample T test was used to analyze the data before and after aging. Two-way ANOVA was adopted to analyze the effect of composition and aging condition on the mechanical-physical properties (α = 0.05). ResultsPU-PG-75% performs lower volume shrinkage (1.35 %). As the increase of filler content, the water sorption and solubility increased and the depth of cure decreased significantly (P < 0.05). After aging, the flexural strength, elasticity modulus and vickers hardness of commercial products dropped obviously and PU-PG-75wt% was relatively stable. Conclusions20 wt% PU-MA could decrease the volume shrinkage of dental resin composite effectively. 60 days water immersion and 5000 times thermal cycles simultaneously resulted in a significant reduction in the flexural properties for experimental materials. PU-PG-75% may have the potential to be taken as a low shrinkage dental resin composite with good mechanical properties. Clinical SignificanceThis new synthesized composite could perform low polymerization shrinkage and better mechanical resistance, which may provide a new idea for improving the lifespan of direct restoration.

Evolution of microstructure and properties of CuCr50 alloy prepared by liquid phase sintering coupled with complementary copper infiltration

CuCr alloy has become the preferred contact material in the field of environmental protection vacuum switches because of its good mechanical and electrical properties, and the development of preparation technology of highly dense and homogeneous CuCr alloy has become one of its research directions. In this paper, the concepts of liquid phase sintering and complementary copper infiltration are coupled to prepare CuCr50 alloys, which are subjected to secondary treatment using solid solution as well as aging heat treatments, to observe the evolution of the microstructure and properties of CuCr50 alloys. It is found that CuCr50 alloy can be prepared stably by liquid phase sintering coupled with complementary copper infiltration. The average particle size of the Cr-rich phase in CuCr50 alloy is 48.9 μm after liquid phase sintering, solid solution treatment and aging treatment, and the uniformity of the distribution of the Cr-rich phase is improved compared with the billet and sintered state. At this time, the density of the CuCr50 alloy is 7.94 g·cm−3, the electrical conductivity is 22.77 MS·m−1, and the hardness reaches 113.2 HB. Compared with the requirements in the national standard GB/T 26867-2011, the density, conductivity, and hardness are increased by 0.51%, 42.3%, and 41.5%, respectively. The peak of the density of states at energies around −5 eV on the total density of states diagram is contributed by the superposition of the 3d orbitals of Cu and the 3d orbitals of Cr, which is a reason for the stable existence of the CuCr50 alloy.

Robust self-healing capacity and high mechanical properties of castor oil-based waterborne polyurethane based on “kill two birds with one stone” strategy

Achieving ideal combination of high self-healing efficiency and good mechanical properties is of significance for the breakthrough in the application of self-healing materials. Herein, the functionalized castor oil-based waterborne polyurethane (DA-CWPU) was constructed based on “killing two birds with one stone” molecular design strategy with the addition of self-healing monomer D-A adduct. Firstly, D-A adduct containing flexible D-A bonds and rigid ring structure was prepared by D-A reaction with furfuryl alcohol (FA) and bismaleimide (BMI) as raw materials, which could not only effectively enhanced the self-healing ability of the material, but also ensured the strong mechanical properties. Then, DA-CWPU emulsion with favourable self-healing and mechanical properties was synthesized by the polymerization of castor oil (CO), isophorone diisocyanate (IPDI) and D-A adduct. The DA-CWPU film has preferable self-healing efficiency (93 % at 100 °C for 50 min), unique shape memory effect (rehabilitate after heating at 100 °C for 45 s), good toughness (485 MJ/m3), strong tensile strength (5.96 MPa) and sufficient elongation (115 %). At the same time, the self-healing DA-CWPU film can be recycled through solution casting. The sustainable castor oil-based waterborne polyurethane can be used as finishing agents for leather products, which realizes repeatedly self-healing in case of surface damage, greatly increasing the service life of the material and mechanical properties, providing a new approach for the development of mechanically robust self-healing materials.

A Review On Multi objective Optimisation of Process Parameters in Shielded Metal Arc Welding For Joining Stainless Steel 3041 And Mild Steel 1018

Due to Mechanical properties of the welding metal and heat affected zone (HAZ) is quality of welding in this research work the review of Multi-objective optimization of welding process parameters for obtaining best weld strength with good mechanical properties of dissimilar metals like stainless steel 3041 and Mild steel 1018 is done. This process used for welding is shielded Metal Arc welding and dissimilar metal are stainless steel 3041 and mild steel 1018. Welding speed, depend on electric property like current Voltage electrode angle, feed rate, Arc length are taken as controlling variables. The weld strength (N/mm2) and Bead geometry variables and Heat Affected Zone are obtained by set of experiment, the possible best outcomes and best method has been chosen by this research. Keywords: HAZ, Multi objective optimization, Response surface Methodology, Shielded metal arc welding

Design and development of low‐weight and high‐strength electromagnetic shielding nanocomposite in a microwave frequency range

AbstractIn this novel work, we fabricated the multiwalled carbon nanotubes (MWCNTs)/polypyrrole (PPy) nanocomposite by employing the novel ultrasonic dual mixing (UDM) method. Subsequently, the atomistics and structural characterizations of the fabricated MWCNT/PPy nanocomposite (PM) were performed using SEM, Raman, and XRD. Furthermore, we experimentally evaluated the mechanical properties of the fabricated PM by reinforcing the PPy matrix with MWCNTs at different wt.%. The experimental study of PM shows that the mechanical properties depend upon the amount and dispersion quality of MWCNTs in the PPy matrix. In order to validate the experimental outcomes, the conservative fully coupled finite element (FE) models were developed using the ANSYS Workbench and novel FEAST software. The electromagnetic interference (EMI) shielding effectiveness (SE) of developed PM was also calculated at different thicknesses of PM by taking the effect of SE due to absorption (SEA) and SE reflection (SER) in the microwave frequency range of the C‐band (5.37–8.2 GHz) into consideration. The total SE (SET), the cumulative sum of SEA and SER, is the strong function of the thickness of the PM. Additionally, our study's outcomes reveal that as the thickness of the PM increased, the SET also increased by dominating the SEA rather than the SER. The SET value of 75 dB was observed for a sample with a thickness of 3 mm, indicating a high level of shielding. Thus, material becomes a highly attractive option for achieving high‐performance EMI SE in the C‐band for satellite communications, Wi‐Fi devices, weather radar systems, surveillance, and cordless telephones. A complex permittivity and permeability were also studied using the Nicolson–Ross–Weir (NRW) method to understand the mechanism behind the EMI SE.Highlights Nanocomposite fabricated using the novel ultrasonic dual mixing method. FE models were developed to validate experimental results. The EC and EMI SE are improved with the increase in the sample thickness. Absorption, rather than reflection, dominated the shielding mechanism. SE was observed dB with good mechanical properties.

Physical, Mechanical, and Flammability Properties of Wood-Plastic Composites (WPC) Containing Beech-Wood Flour and Flame-Retardant Additives.

This study aims to develop a recyclable, economical, and flame-retardant composite material using polypropylene, beech flour, tetrabromobisphenol A bis (TBBPA), and antimony trioxide (ATO). Flame-retardant additives (TBBPA and ATO) were initially added into polypropylene at different rates, and masterbatch (MB) samples were produced by the extrusion method. Subsequently, different percentages of wood flour (10%, 15%, 20%, 25%, and 30%) along with 60% MB were added to the polypropylene to create wood-polymer composites (WPC) using the injection method. The TBBPA, ATO, and wood flour were introduced through side-feeding hoppers during injection to ensure a homogeneous distribution within the WPC. Physical, thermal, and mechanical tests were conducted on the WPC samples. Additionally, TGA, FTIR, and SEM analyses were performed. The results indicated that the optimal ratios for TBBPA and ATO additives were 20% and 10%, respectively. It was observed that increasing the wood flour content in the WPC samples led to enhanced density, water absorption, hardness, impact, and abrasion resistance. Conversely, MFI, bending strength, and tensile strength decreased with higher wood flour content. It was observed that WPC samples exhibited flame resistance up to 725 °C. The produced WPC materials can be used in flooring applications, interior furniture, decorative wall panels, and aesthetic structural elements due to their fire behavior, good mechanical properties, low water-absorption rates, and aesthetic appearance.

Development of an implantable sensor system for in vivo strain, temperature, and pH monitoring: comparative evaluation of titanium and resorbable magnesium plates

Biodegradable magnesium is a highly desired material for fracture fixation implants because of its good mechanical properties and ability to completely dissolve in the body over time, eliminating the need for a secondary surgery to remove the implant. Despite extensive research on these materials, there remains a dearth of information regarding critical factors that affect implant performance in clinical applications, such as the in vivo pH and mechanical loading conditions. We developed a measurement system with implantable strain, temperature, pH and motion sensors to characterize magnesium and titanium plates, fixating bilateral zygomatic arch osteotomies in three Swiss alpine sheep for eight weeks. pH 1–2 mm above titanium plates was 6.6 ± 0.4, while for magnesium plates it was slightly elevated to 7.4 ± 0.8. Strains on magnesium plates were higher than on titanium plates, possibly due to the lower Young's modulus of magnesium. One magnesium plate experienced excessive loading, which led to plate failure within 31 h. This is, to our knowledge, the first in vivo strain, temperature, and pH data recorded for magnesium implants used for fracture fixation. These results provide insight into magnesium degradation and its influence on the in vivo environment, and may help to improve material and implant design for future clinical applications.

Mechanical and broadband absorption properties of Nextel 610/SiOC composites synergistically enhanced by the interfacial structure design

In this work, BN interphase and Si3N4 matrix were prepared by chemical vapor infiltration (CVI) to optimize the mechanical properties of N610/SiOC composites, and the strengthening and toughening mechanisms were investigated. The results showed that the content and distribution of Si3N4 matrix and the thickness of BN interphase could tailor the strength and toughness of composites simultaneously. The optimal tensile strength of 234 MPa and flexural strength of 338 MPa were obtained by Si3N4 reinforced N610/SiOC composites with a BN interphase thickness of 540 nm, respectively. Meanwhile, free carbon modified BN interphase (BN(C)) and multi-layer “mortise and tenon” joint were designed to optimize the broadband EMW absorption. The impedance-matching “mortise and tenon” joint achieved a wide effective absorption bandwidth (EAB) of 8.4 GHz and a minimum reflection loss (RLmin) of −52.55 dB. This work inspires designing and fabricating CMC with both good mechanical and broadband EMW absorption properties.

Role of Mo and Zr Additions in Enhancing the Behavior of New Ti–Mo Alloys for Implant Materials

AbstractThe utilization of Ti–Mo alloys in biomedical applications has gained attention for use in biomedical applications owing to their non-toxicity, reasonable cost, and favorable properties. In the present study, Ti–12Mo–6Zr and Ti–15Mo–6Zr alloys were prepared using elemental blend and mechanical alloying techniques. The effect of alloying elements Mo and Zr of Ti–Mo alloy, as well as the effect of fabrication techniques of Ti–Mo–Zr trinary alloys, were investigated. Thermodynamic calculations supported by CALPHAD analysis revealed that the addition of Zr increases lattice distortion, which contributes to enhancing the strength. Conversely, adding Mo decreases the enthalpy, facilitating improved mixing and solid solution formation. The as-sintered samples were characterized by X-ray diffraction, optical microscope, and scanning electron microscopy, and their microhardness, compressive, and corrosion behavior were investigated. Among all the investigated alloys, Ti–15Mo–6Zr alloy prepared by the mechanical alloying technique, milled for six hours at 300 rpm, compacted at 600 MPa, and sintered at 1250 ℃, shows good comprehensive mechanical properties with a preferable compressive strength (− 1710 MPa) and hardness (396 HV5), as well as the lowest wear rate (0.69%) and corrosion rate (0.557 × 10–3 mm/year). This can be related to the solid solution strengthening and relative density, together with dispersion and precipitation strengthening of the α phase. Remarkably, the combination of high mechanical and corrosion properties can be achieved by tailoring the content of the α phase, controlling the density, and providing new fabricating techniques for β Ti alloys. Graphical Abstract

Anti-tumor effects of ellagic acid and mesenchymal stem cell-conditioned medium on breast cancer cells on the 3D printed PCL/agarose scaffolds

Numerous investigations have demonstrated that natural bioactive compounds, such as flavonoids, exhibit synergistic effects with anticancer agents utilized in clinical practice. Stem cell therapies play a critical role in the domain of oncology; nevertheless, conflicting results have surfaced regarding the potential pro-cancer or anti-cancer characteristics of mesenchymal stem cells. The primary aim of the current investigation was to examine the anticancer efficacy of ellagic acid (EA) alone or in combination with adipose tissue stem cells derived conditioned medium (ADSCs-CM) on human breast cancer cells. In order to overcome the potential effects of two-dimensional (2D) culture, a three-dimensional (3D) printed polycaprolactone (PCL)/agarose scaffold is utilized to evaluate cancer cell behavior. More recently it was reported this scaffold had open and interconnected pores, as well as good water absorption and mechanical properties. Assessment of MCF-7 cancer cell viability was conducted through MTT assay, flow cytometry, cell cycle assay, and quantitative real-time PCR within a 3D cell culture framework. The outcomes revealed a reduction in cancer cell viability across all treatment cohorts in comparison to the control group. Particularly noteworthy was the significantly enhanced effect of the EA and CM combination relative to each component administered individually. Flow cytometry assessment using annexin V/PI staining indicated a decrease in cancer cells, particularly evident in the combination-treated group. Furthermore, the mRNA expression levels of BAX, BCL2, vascular endothelial growth factor (VEGF), and caspase 3 genes were consistent with pathways associated with apoptosis. Consequently, the synergistic anti-proliferative impact of EA in conjunction with ADSCs-CM on MCF-7 cells has been substantiated. These findings have two important implications for breast cancer research; highlight the utility of the PCL/agarose scaffold as a cancer model and suggest new avenues for the development of adjuvant anticancer therapeutic approaches.

Polymerization-Induced Self-Assembly Providing PEG-Gels with Dynamic Micelle-Crosslinked Hierarchical Structures and Overall Improvement of Their Comprehensive Performances.

Polymer gels are fascinating soft materials and have become excellent candidates for wearable electronics, biomedicine, sensors, etc. Synthetic gels usually suffer from poor mechanical properties, and integrating good mechanical properties, adhesiveness, stability, and self-healing performances in one gel is more difficult. Herein, polymerization-induced self-assembly (PISA) providing PEG-gels with an overall improvement in their comprehensive performances is reported. PISA synthesis is carried out in PEG (solvent) to efficiently produce various nanoparticles, which are used as the nanofillers in the subsequent synthesis of PEG-gels with dynamic micelle-crosslinked hierarchical structures. Compared to hydrogels, PEG-gels show excellent long-term stability due to the nonvolatile feature of PEG solvent. The hierarchical PEG-gels (with nanofillers) exhibit better mechanical and adhesive properties than the homogeneous-gels (without nanofillers). The energy dissipation mechanism of the PEG-gels is analyzed via stress relaxation and cyclic mechanical tests. High-density hydrogen bonds between the micelles and PAA matrix can be broken and reformed, endowing better self-healing properties of the dynamic micelle-crosslinked PEG gels. This work provides a simple strategy for producing hierarchical structural gels with enhanced properties, which offers fundamentals and inspirations for the designing of various advanced functional materials.

Effect of Zn on Microstructure and Wear Resistance of Sn-Based Babbitt Alloy

Tin-based Babbitt alloys are a widely used bearing bushing material which have good comprehensive properties. However, problems such as high-temperature softening and insufficient bearing capacity occur during their use, so the optimization of tin-based Babbitt alloys has become a research hotspot. In this paper, ZChSnSb11-6 alloy was mainly prepared by the gravity casting method, and different amounts of Zn were added to the alloy (the mass fraction values were 0 wt.%, 0.05 wt.%, 0.1 wt.%, 0.15 wt.%, and 0.2 wt.%, respectively). Through the hardness test, the tensile test, the friction and wear test, and the microstructure observation of the prepared alloy, the influence of Zn on the organization and properties of the ZChSnSb11-6 alloy was analyzed. The results show that the size of the SnSb hard phase changed with the increasing content of Zn. The size of the hard phase of the SnSb tended to increase first and then decrease, and the number of phase particles increased first and then decreased, resulting in changes in performance. Through comparison, it was learned that the addition of Zn can effectively improve the hardness, tensile strength, yield strength, and wear resistance of the alloy, but the elongation rate was reduced. When the Zn content was 0.1 wt.%, the hardness value of the alloy reached the maximum value, 25.82 HB, which increased by 7.3% when compared with the sample without Zn. The hardness of the Zn, 0.15 wt.%, is close to that of the Zn, 0.1 wt.%. Compared to the sample without Zn, the tensile strength and elongation of the alloy were maximized at a Zn content of 0.15 wt.%. Compared to the sample without the Zn, the tensile strength was increased by 21.29%, and the elongation rate was increased by 46%. An analysis showed that the alloy has good comprehensive mechanical properties when the Zn content is 0.15 wt.%.

Epoxy Based Composite Material from the Coconut Fiber

Recently the composite material is made up of various other types of natural fibers including some epoxy resins materials. Because some natural fibers have a tendency to provide a good mechanical properties and durability also and it is safe for the environment. In this research we focused on the various testing parameters like tensile test and impact test because we won’t to have a better mechanical properties and good result also. The composite material prepared like epoxy resin with coconut fiber by using a hand laid method. The fabricated sheet is tested by various mechanical properties and it’s a very good application for us.

Fabrication of PBAT/lignin composite foam materials with excellent foaming performance and mechanical properties via grafting esterification and twin-screw melting free radical polymerization

As one of the mainstream biodegradable materials, poly(butylene adipate-co-terephthalate) (PBAT) foams offer a sustainable alternative to traditional plastic foams, effectively reducing environmental pollution. However, the high cost and poor mechanical performance of PBAT foams impede their practical application. Herein, the glycidyl methacrylate-grafted biomass lignin (GML) was used to produce a PBAT/GML composite foam with good foaming performance and mechanical properties at high lignin-filling amounts by twin-screw melting free radical polymerization and supercritical CO2 foaming process. The compatibility of GML in the PBAT matrix was improved due to the formation of ester bonds in modified lignin, endowing the PBAT/GML (PGML) composite foam with exceptional foaming performance. Additionally, the mechanical properties of PGML composite foam were remarkably enhanced due to the introduction of the abundant aromatic structures of GML and the construction of a stable covalent crosslinking network. The compressive strengths and compression modulus of the PGML foam were improved by 2.53 times and 2.47 times, while its bending strength and bending modulus were improved by 1.27 times and 3.92 times compared to the neat PBAT. This research affords a new strategy for developing low-cost biodegradable biomass PBAT/lignin composite foam materials with good foaming performance and mechanical properties.Graphical abstract

Perioperative Outcomes: Polycarbonate Polyurethane Artificial Blood Vessel Versus Polyester Artificial Blood Vessel.

The objective of this study was to compare the perioperative performance of the novel large-diameter composite polycarbonate polyurethane graft and the polyester graft. In this study, we retrospectively analyzed 14 patients with thoracic aortic prosthesis replacement from 2016 to 2021. The preoperative, intraoperative, and postoperative data of the 2 groups were assessed in detail. We defined the patients with polyester grafts as the control group and the patients with polycarbonate polyurethane grafts as the experimental group. The total operation time of the experimental group was significantly shorter than that of the control group, which were 159.29±38.13 minutes and 252.57±64.40 minutes, respectively (p<0.001). The length of time from aortic opening to the end of operation in the experimental group was significantly shorter than that in the control group, which were 70.43±8.08 minutes and 124.71±37.59 minutes, respectively (p<0.001). The mean total drainage of pleural fluid was lower in the experimental group than in the control group (383.43±139.68 mL vs. 828.00±457.27 mL; p<0.05). The mean postoperative in-hospital time was shorter in the experimental group than in the control group (6.71±0.75 days vs. 9.43±2.82 days; p<0.05). This study provides preliminary evidence that the novel artificial blood vessel has good mechanical properties, histocompatibility, hemocompatibility, and anti-seepage function in the human body. A multicenter randomized controlled trial is needed for further validation. The novel hybrid polycarbonate polyurethane (PCU)/polyester three-layered large-diameter artificial blood vessel simulates the internal, middle, and external layers of the human blood vessels. The inner and outer layer are made of PCU, and the middle reinforcing layer is woven by polyester. Because of the three-layered structure, this artificial blood vessel has excellent anti-seepage and anti-infection functions. the inner and outer layers of the blood vessel made of PCU let this artificial blood vessel has excellent blood compatibility, outstanding biocompatibility, high endothelialization rate, and 100% patency. By comparing the perioperative outcomes with the polyester artificial blood vessel, we find it has good mechanical properties, histocompatibility, hemocompatibility and anti-seepage function in the human body.

Organic polymer composite with inorganic SiO2 particles for mechanical robustness and self-cleaning anti-reflective coatings

Anti-reflective coatings prepared from SiO2 nanoparticles have excellent anti-reflective properties, but the coating's poor mechanical properties and low self-cleaning performance limit its practical application. In this work, SiO2 nanoparticles were modified into hydrophobic particles using surface modification, and then organic polymer were added as a binder to formulate SiO2 sols, which were coated onto a glass substrate to form a anti-reflective coating. The coating can enable the glass substrate to achieve a transmittance of 99.1 % at 580 nm, and it can increase the average transmittance of the glass substrate from 89.6 % to 96.2 % in the 400–1100 nm band. In addition, the coatings prepared from hydrophobic SiO2 nanoparticles composite organic polymers have a water contact angle of 136°, resulting in good self-cleaning properties. The organic polymers can connect the SiO2 nanoparticles together, increasing the mechanical properties of the coating. This multifunctional anti-reflective coating with high transmittance, good mechanical properties and self-cleaning is beneficial in many applications, such as photovoltaic glass, architectural glass, displays and more.