Clinical evaluation of the efficacy of a new bone cement-injectable cannulated pedicle screw in the treatment of spondylolysis-type lumbar spondylolisthesis with osteoporosis: a retrospective study.

PURPOSE: To investigate the clinical efficacy and safety of a bone cement-injectable cannulated pedicle screw (CICPS) in the treatment of spondylolysis-type lumbar spondylolisthesis with osteoporosis. METHODS: A retrospective study was conducted on 37 patients (Dual-energy X-ray bone density detection showed different degrees of osteoporosis) with spondylolysis-type lumbar spondylolisthesis who underwent lumbar spondylolisthesis reduction and fusion using a new type of injectable bone cement screw from May 2011 to March 2015. Postoperative clinical efficacy was evaluated by the Visual Analogue Scale (VAS) scores and the Oswestry Disability Index (ODI). Imaging indexes were used to evaluate the stability of internal fixation of the devices 1, 3, 6, and 12 months after surgery and annually thereafter. The safety of the CICPS was assessed by the prevalence of intraoperative and postoperative complications. RESULTS: A total of 124 CICPS were implanted intraoperatively. Bone cement leakage occurred in 3 screws (2.42%), and no clinical discomfort was found in any patients. All 37 patients were followed up with an average follow-up time of 26.6 ± 13.4 months (12-58 months). In the evaluation of the clinical effects of the operation, the average postoperative VAS score of the patients decreased from 4.30 ± 1.58 before surgery to 0.30 ± 0.70 after surgery (P < 0.001), and the ODI decreased from 47.27% ± 16.97% before surgery to 3.36% ± 5.70% after surgery (P < 0.001). No screw was loose, broken or pulled out. CONCLUSION: CICPS is safe and effective in the treatment of spondylolysis-type lumbar spondylolisthesis complicated by osteoporosis.

First-in-man study of a thinner-strut sirolimus-eluting bioresorbable scaffold (FUTURE-I): Three-year clinical and imaging outcomes.

OBJECTIVES: The FUTURE-I study aimed to assess preliminary safety and effectiveness with the long-term clinical and imaging follow-up for the Firesorb (MicroPort, Shanghai, China), a thinner-strut sirolimus-eluting bioresorbable scaffold (BRS). BACKGROUND: First-generation BRS has been associated with unexpected device-related adverse outcomes at long-term follow-up. METHODS: In this prospective, open-label, first-in-man study, patients with single de novo lesions in native coronary arteries were randomized 2:1 into two cohorts after successful Firesorb implantation: cohort 1 (n = 30) underwent multimodality imaging assessment at 6 and 24 months; and cohort 2 (n = 15) at 12 and 36 months. All patients underwent clinical follow-up at 1, 6, and 12 months and annually up to 5 years. RESULTS: Between January and March 2016, 45 patients were enrolled. At 3-year follow-up, one patient had experienced target lesion failure and none scaffold thrombosis. In-scaffold minimal lumen diameter decreased significantly from 6-month to 2-year (2.53 ± 0.24 mm vs. 2.27 ± 0.37 mm, p = .0003), and only numerically from 1-year to 3-year follow-up (2.48 ± 0.28 mm vs. 2.22 ± 0.13 mm, p = .08). By optical coherence tomography, neointimal strut coverage at 3-year follow-up was 99.8%, and very low rate of late scaffold discontinuity was observed, only in one patient on two cross sections with three malapposed struts. CONCLUSIONS: At 3-year follow-up of the FUTURE-I study, implantation of the thinner-strut Firesorb BRS appeared preliminary feasible and effective in the treatment of patients with noncomplex coronary lesions.

Randomized comparison of novel biodegradable polymer and durable polymer-coated cobalt-chromium sirolimus-eluting stents: Three-Year Outcomes of the I-LOVE-IT 2 Trial.

OBJECTIVES: We aimed to compare the long-term outcomes of the novel biodegradable polymer cobalt-chromium sirolimus-eluting stent (BP-SES) versus the durable polymer sirolimus-eluting stent (DP-SES) in the I-LOVE-IT2 trial. BACKGROUNDS: Comparisons of the long-term safety and efficiency of the BP-DES versus the DP-DES are limited. METHODS: A total of 2,737 patients eligible for coronary stenting were randomized to the BP-SES or DP-SES group at a 2:1 ratio. The primary endpoint of target lesion failure (TLF) was defined as a composite of cardiac death, target vessel myocardial infarction (MI), or clinically indicated target lesion revascularization. RESULTS: A three-year clinical follow-up period was available for 2,663 (97.3%) patients. There were no significant differences in TLF (8.9% vs. 8.6%, P = 0.81), patient-oriented composite endpoint (PoCE) (15.2% vs.14.5%, P = 0.63), or individual components between the BP-SES and DP-SES. Definite/probable stent thrombosis (ST) was low and similar at 3 years (0.8% vs. 1.0%, P = 0.64). Landmark analysis of 1-3 years showed that the TLF (2.7% vs. 2.6%, P = 0.81), PoCE (6.2% vs. 5.1%, P = 0.28), and definite/probable ST (0.4% vs. 0.4%, P = 1.00) were comparable between the 2 arms. CONCLUSIONS: In this prospective randomized trial, the BP-SES showed similar clinical results versus the DP-SES in terms of safety and efficacy outcomes over a 3-year follow-up period.

Comparison of two biodegradable-polymer-based sirolimus-eluting stents with varying elution and absorption kinetics in patients with acute myocardial infarction: A subgroup analysis of the PANDA III trial.

BACKGROUND: Implantation of early-generation metallic drug-eluting stents (DES) in patients with acute myocardial infarction (AMI) is associated with poor vessel wall healing. Use of biodegradable polymer (BP) DES might improve safety outcomes; however, the impact of varying drug elution and polymer absorption kinetics of BP-DES on clinical outcomes in the AMI population is unknown. METHODS: This subgroup analysis of the randomized PANDA III trial included 732 patients (366 in each group) presenting with recent (<1 month) AMI. Primary endpoint was 1-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction (MI), or ischemia-driven target lesion revascularization. Secondary endpoints included a patient-oriented composite endpoint (PoCE) of all-cause death, all MI, or any revascularization; individual TLF and PoCE components; and definite/probable stent thrombosis (ST). RESULTS: There were no significant differences between-groups in baseline clinical, angiographic, or procedural characteristics other than the proportion of post-dilatation, which was performed more frequently with the BuMA stent (53.9% vs. 44.5%; P = 0.004). After 1 year, compared to Excel SES implantation in patients with AMI, BuMA was associated with similar incidences of TLF and PoCE (5.5% vs. 8.3%, P = 0.14; 8.8% vs. 9.9%, P = 0.61, respectively) but lower incidences of MI (2.5% vs. 6.1%, P = 0.02), target vessel MI (2.2% vs. 5.8%, P = 0.01), and definite/probable ST (0.3% vs. 2.2%, P = 0.04). CONCLUSIONS: BuMA SES, with faster drug elution rate and polymer absorption kinetics, might improve safety outcomes compared to Excel SES in the high-risk AMI population. © 2017 Wiley Periodicals, Inc.

Micro crystalline cellulose aided surface modification and deposition of green polyelectrolytes for the improved hydrophilicity and flame retardancy of polyamide 66 fabric.

In this work, microcrystalline cellulose (MCC) treated polyamide 66 (PA66) textiles were coated with green and naturally abundant polysaccharides specifically, chitosan (CS) and sodium alginate (SA) together with phytic acid (PA) via layer by layer (LbL) deposition. The prime focus of such treatment was to intensify both the hydrophilic and flame retardant properties of PA66 fabric substrates. Subsequently, the prepared coatings were further subjected to cross-linking modification by dipping them into the barium (Ba) salt solution. Obtained results indicated that the MCC-modified PA66 exhibited a water contact angle (WCA) value of 00 and revealed a drop in peak heat release rate (pHRR) up to 31 % with complete suppression of melt-dripping. Meanwhile, the Ba-ion-induced cross-linking treatment further escalated this reduction up to 36 % by adding enhanced thermal stability, improved char quality along better wash durability of as prepared coatings. In addition, the combined modification of PA66 textiles with MCC and Ba-ion handed a superb enhancement of physical properties like tensile strength by ca. 50 % compared to the pure PA66. Thus, this MCC-assisted surface modification paves the way for a new kind of greener treatment of PA66 textiles in attaining superior hydrophilic and flame retardant properties of the same.

Polystyrene nanoplastics induce vascular stenosis via regulation of the PIWI-interacting RNA expression profile.

Nanoplastics (NPs) have become common worldwide and attracted increasing attention due to their serious toxic effects. Owing to their higher surface area and volume ratios and ability to easily enter tissues, NPs impose more serious toxic effects than microplastics. However, the effect of NP exposure on vascular stenosis remains unclear. To measure the effects of polystyrene NP (PS-NP) exposure on vascular toxicity, we conducted analyses of blood biochemical parameters, pathological histology, high-throughput sequencing, and bioinformatics. Red fluorescent PS-NPs (100 nm) were effectively uptake by mouse vascular arterial tissue. The uptake of PS-NPs resulted in vascular toxicity, including alterations in lipid metabolism and thickening of the arterial wall. Based on PIWI-interacting RNA (piRNA) sequencing, 1547 and 132 differentially expressed piRNAs (DEpiRNAs) were detected in the PS-NP treatment group after 180 and 30 days, including 787 and 86 upregulated and 760 and 46 downregulated compared with the control group, respectively. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the target genes of DEpiRNAs were mostly involved in cell growth and cell motility-related signaling, such as the MAPK signaling pathway. This is the first study to highlight the alteration in piRNA levels in mouse vascular arterial tissue after PS-NP exposure. This study adds to the knowledge regarding the regulatory mechanism of pathological changes induced by PS-NP exposure.

A novel tiRNA-Glu-CTC induces nanoplastics accelerated vascular smooth muscle cell phenotypic switching and vascular injury through mitochondrial damage.

Nanoplastics pose several health hazards, especially vascular toxicity. Transfer RNA-derived small RNAs (tsRNAs) are novel noncoding RNAs associated with different pathological processes. However, their biological roles and mechanisms in aberrant vascular smooth muscle cell (VSMC) plasticity and vascular injury are unclear. This study investigated the potent effects of tsRNAs on vascular injury induced by short- and long-term exposure to polystyrene nanoplastics (PS-NPs). Mice were exposed to PS-NPs (100 nm) at different doses (10-100 µg/mL) for 30 or 180 days. High-throughput sequencing was used to analyze tsRNA expression patterns in arterial tissues obtained from an in vivo model. Additionally, quantitative real-time polymerase chain reaction, fluorescent in situ hybridization assays, and dual-luciferase reporter assays were performed to measure the expression and impact of tiRNA-Glu-CTC on VSMCs exposed to PS-NPs. Short-term (≥50 µg/mL, moderate concentration) and long-term (≥10 µg/mL, low concentration) PS-NP exposure induced vascular injury in vivo. Cellular experiments showed that the moderate concentration of PS-NPs induced VSMC phenotypic switching, whereas a high concentration of PS-NPs (100 µg/mL) promoted VSMC apoptosis. PS-NP induced severe mitochondrial damage in VSMCs, including overexpression of reactive oxygen species, accumulation of mutated mtDNA, and dysregulation of genes related to mitochondrial synthesis and division. Compared with the control group, 13 upregulated and 12 downregulated tRNA-derived stress-induced RNAs (tiRNAs) were observed in the long-term PS-NP (50 µg/mL) exposure group. Bioinformatics analysis indicated that differentially expressed tiRNAs targeted genes that were involved in vascular smooth muscle contraction and calcium signaling pathways. Interestingly, tiRNA-Glu-CTC was overexpressed in vivo and in vitro following PS-NP exposure. Functionally, the tiRNA-Glu-CTC inhibitor mitigated VSMC phenotypic switching and mitochondrial damage induced by PS-NP exposure, whereas tiRNA-Glu-CTC mimics had the opposite effect. Mechanistically, tiRNA-Glu-CTC mimics induced VSMC phenotypic switching by downregulating Cacna1f expression. PS-NP exposure promoted VSMC phenotypic switching and vascular injury by targeting the tiRNA-Glu-CTC/Cacna1f axis.

Self-Supplied Reactive Oxygen Species-Responsive Mitoxantrone Polyprodrug for Chemosensitization-Enhanced Chemotherapy under Moderate Hyperthermia.

Currently, the secondary development and modification of clinical drugs has become one of the research priorities. Researchers have developed a variety of TME-responsive nanomedicine carriers to solve certain clinical problems. Unfortunately, endogenous stimuli such as reactive oxygen species (ROS), as an important prerequisite for effective therapeutic efficacy, are not enough to achieve the expected drug release process, therefore, it is difficult to achieve a continuous and efficient treatment process. Herein, a self-supply ROS-responsive cascade polyprodrug (PMTO) is designed. The encapsulation of the chemotherapy drug mitoxantrone (MTO) in a polymer backbone could effectively reduce systemic toxicity when transported in vivo. After PMTO is degraded by endogenous ROS of the TME, another part of the polyprodrug backbone becomes cinnamaldehyde (CA), which can further enhance intracellular ROS, thereby achieving a sustained drug release process. Meanwhile, due to the disruption of the intracellular redox environment, the efficacy of chemotherapy drugs is enhanced. Finally, the anticancer treatment efficacy is further enhanced due to the mild hyperthermia effect of PMTO. In conclusion, the designed PMTO demonstrates remarkable antitumor efficacy, effectively addressing the limitations associated with MTO.

Ethanol inducing self-assembly of poly-(thioctic acid)/graphene supramolecular ionomers for healable, flame-retardant, shape-memory electronic devices.

In recent years, flexible electronic devices have great application potential in the fields of healthcare, VR virtual reality, electronic skin and intelligent robots. However, electronic devices fail during operation due to fatigue, corrosion or damage, making it difficult and expensive to maintain highly integrated portable/wearable electronic devices. In this study, highly healable, flame retardant, shape memorized supramolecular PTAZ/GO was fabricated by restricting the crosslinking of zinc ions, carboxyl graphene and poly-(thioctic acid) via self-polymerization in ethanol inducing self-assembly. The rich carboxyl groups associated with hydroxyl and disulfide groups in the system provide excellent self-healing efficiency and shape memory properties for supramolecular ionomers. The results of a microscale combustion calorimeter (MCC) test in this study showed a 65.3 % reduction in the peak heat release rate (pHRR) for ionomers compared to pure polymer, thus implying that ionic coordination cross-linking and GO nanosheets are beneficial for improving the fire safety of the materials. For the shape-memory device, the supramolecular elastomers can switch LED lights on and off by changing the shape, and the conductivity can be restored after reconnection of two damaged parts. Thus, the proposed materials have wide applications in electronic engineering.

A novel green phosphorus-containing flame retardant finishing on polysaccharide-modified polyamide 66 fabric for improving hydrophilicity and durability.

Rising concerns about the toxic effects and environmental issues associated with various fireproof treatments on textiles have led to a demand for "green" materials. Chitosan (CS) is an amino polysaccharide green, recyclable, and non-toxic highly biocompatible biopolymer that consists of multiple hydroxyl groups and has a wide range of applications, including as a flame retardant additive. In this study, an eco-friendly bio-based formaldehyde-free flame retardant containing a higher level of phosphorus and nitrogen in phytic acid ammonia (PAA) was synthesized to amplify the most plentiful green chitosan (CS)-modified polyamide 66 (PA66) fabric surface through a simple pad-dry-cure technique for the improvement of durable flame retardancy with hydrophilicity. The findings revealed that each UV-grafted CS fabric could entirely stop the melt-dripping tendency during the vertical burning (UL-94) test and reached a V-1 rating. Meanwhile, limiting oxygen index (LOI) testing showed a rapid increase from 18.5 % to 24 % for the PA66 control and the PAA-treated (i.e., PA66-g-5CS-PAA) fabric samples, respectively. Moreover, compared to the PA66 control sample, a dramatic decrease in the peak heat release rate (PHRR), fire growth rate (FGR), and total heat release (THR) by approximately over 52 %, 0.63 %, and 19.7 %, respectively, was observed for the PA66-g-5CS-PAA fabric sample. Additionally, this arrangement of PAA catalyzed the charring of grafted CS and acted as a condensed phase flame retardant, resulting in a significant improvement in char yield% in both air and N2 atmospheres for the PA66-g-5CS-PAA fabric sample in TGA. In addition, only the lower grafting ratio of CS with PAA-treated fabric sample (i.e., PA66-g-2CS-PAA) could encourage it to gain its lowest water contact angle of 00, as well as impersonating a positive effect in improving the flame retardant coating durability in washing and sustaining even after 10 home laundering cycles. This phenomenon suggests that an actual hydrophilic and durable flame retardant finishing procedure for polyamide 66 fabrics might be applied with the novel, plentiful, sustainable, and environmentally friendly bio-based green PAA ingredient.

Biomass-derived polyphosphazene toward simultaneously enhancing the flame retardancy and mechanical properties of epoxy resins.

As one of the most widely used polymers, the intrinsic brittleness and high flammability bring about a stringent requirement for the practical application of epoxy resins (EPs). It is difficult to toughen EP without compromising its mechanical and thermal properties for many conventional toughening agents. Here, a novel furan-derived bio-based polyphosphazene (PFMP) with a flexible backbone and rigid side groups was prepared by the nucleophilic substitution reaction between polydichlorophosphazene (PDCP) and furfuralcohol. The resultant PFMP was incorporated into EP to realize exceptional toughening, strengthening, and flame retardant function. By adding 15% of PFMP, the limit oxygen index value is from 25% (EP) to 33% (EP/PFMP-15) and reaches the UL-94 V-0 rating. According to the cone calorimeter results, EP/PFMP-15 exhibits exceedingly reduced peak heat release rate (pHRR) (50.2%) and total heat release (THR) (49.6%). The significantly increased fire performance index (FPI) and decreased fire growth rate index (FIGRA) of EP/PFMP-15 demonstrate an improvement in its flame retardancy. The catalytic carbonization effect (condensed phase) and radical quenching effect (gas phase) of PFMP account for the greatly improved flame retardancy. Moreover, the impact and tensile tests indicate that PFMP can ameliorate the mechanical performance of EP with a maximum increase of impact strength (111.8%) and elongation at break (35.2%) for EP/PFMP-5. With 15% PFMP added, the tensile strength of EP/PFMP-15 increases by 40.4%. This work demonstrates that PFMP is expected to overcome shortcomings (flammability, toughness, and strength) of EP and spread its applied fields.

Second-generation bone cement-injectable cannulated pedicle screws for osteoporosis: biomechanical and finite element analyses.

BACKGROUND: Biomechanical and finite element analyses were performed to investigate the efficacy of second-generation bone cement-injectable cannulated pedicle screws (CICPS) in osteoporosis. METHODS: This study used the biomechanical test module of polyurethane to simulate osteoporotic cancellous bone. Polymethylmethacrylate (PMMA) bone cement was used to anchor the pedicle screws in the module. The specimens were divided into two groups for the mechanical tests: the experimental group (second-generation CICPS) and control group (first-generation CICPS). Safety was evaluated using maximum shear force, static bending, and dynamic bending tests. Biomechanical stability evaluations included the maximum axial pullout force and rotary torque tests. X-ray imaging and computed tomography were used to evaluate the distribution of bone cement 24 h after PMMA injection, and stress distribution at the screw fracture and screw-cement-bone interface was assessed using finite element analysis. RESULTS: Mechanical testing revealed that the experimental group (349.8 ± 28.6 N) had a higher maximum axial pullout force than the control group (277.3 ± 8.6 N; P < 0.05). The bending moments of the experimental group (128.5 ± 9.08 N) were comparable to those of the control group (113.4 ± 20.9 N; P > 0.05). The screw-in and spin-out torques of the experimental group were higher than those of the control group (spin-in, 0.793 ± 0.015 vs. 0.577 ± 0.062 N, P < 0.01; spin-out, 0.764 ± 0.027 vs. 0.612 ± 0.049 N, P < 0.01). Bone cement was mainly distributed at the front three-fifths of the screw in both groups, but the distribution was more uniform in the experimental group than in the control group. After pullout, the bone cement was closely connected to the screw, without loosening or fragmentation. In the finite element analysis, stress on the second-generation CICPS was concentrated at the proximal screw outlet, whereas stress on the first-generation CICPS was concentrated at the screw neck, and the screw-bone cement-bone interface stress of the experimental group was smaller than that of the control group. CONCLUSION: These findings suggest that second-generation CICPS have higher safety and stability than first-generation CICPS and may be a superior choice for the treatment of osteoporosis.

Covalent grafting diazotized black phosphorus with ferrocene oligomer towards smoke suppression and toxicity reduction.

In comparison with the thermal hazard of polymers, noxious smoke and gas produced by the combustion of polymers make the environment self-purification a huge challenge. As a new type of a highly effective flame retardant, black phosphorus (BP) can effectively decrease the thermal hazard of polymers, but its performances in smoke suppression and toxicity reduction are unsatisfactory. In this article, a method of covalently grafting diazotized BP with a ferrocene oligomer was applied to promote the smoke suppression and toxicity reduction efficiency of BP. In our work, the BP-NH nanomaterials with a mass of amino groups on the surface were acquired by diazotizing the BP. Then, the BP-Fe was obtained by covalently grafting the ferrocene chloride salt and nitrogen-containing heterocycles on the surface of BP. The smoke production rate (SPR) and total smoke production (TSP) values of the epoxy resin (EP) decreased by 49.8% and 52.5% with the addition of 2 wt% BP-Fe, respectively. In comparison with previous studies, this work was far more effective than the previous work in smoke suppression and flame retardant. The release of toxic gases (CO and HCN) and volatile organic compounds in the EP was also effectively inhibited at the same time. In addition, the storage modulus and tensile strength of nanocomposites increased by 35.1% and 27.2% with the addition of 1 wt% BP-Fe. This work also provides a new idea on how to simultaneously strengthen the toxic smoke suppression, mechanical properties, and flame retardant of polymer materials.

Hierarchical core-shell SiO2@COFs@metallic oxide architecture: An efficient flame retardant and toxic smoke suppression for polystyrene.

SiO2@3COFs@CuO and SiO2@3COFs@Fe2O3 are prepared in this study. Then SiO2 and its hybrids are incorporated into PS through solution blending method. The thermal stability, mechanical performance, combustion performance and smoke density of PS and its nanocomposite are investigated. The temperature at 5 wt% weight loss and the maximum weight loss rate of PS/SiO2@3COFs@ Fe2O3 (PS 4) under air are 15 and 14 °C higher than that of neat one, respectively. The glass-transition temperature of PS/SiO2@3COFs (PS 2) is 1.5 °C lower than that of PS, which can conclude that SiO2@3COFs contributes to impact strength of PS 0. The peak heat release rate (20.8%) and total heat release (14.0%) of PS 2 decreases further compared with that of PS 0. The smoke density of PS 4 is 23.1% lower than that of neat PS. The influence of SiO2 and its nano-hybrids on the pyrolysis and combustion of PS is investigated. Incorporation of SiO2 and its nano-hybrids shows little effect on pyrolysis process of PS. However, heat resistance of PS is enhanced obviously and thermal degradation rate of PS is also decreased through incorporation of SiO2 and its nano-hybrids. The gaseous pyrolysis products (aromatic compounds and alkenyl compounds) of PS and its nanocomposite also decrease.

High-performance flexible polyurethane foam based on hierarchical BN@MOF-LDH@APTES structure: Enhanced adsorption, mechanical and fire safety properties.

Improving resilience, enhancing fire safety and adsorption properties were the key points for the preparation of high-performance flexible polyurethane foam (FPUF). Here, MOF-derived petal-like Co/Mg-double metal hydroxide (Co/Mg-LDH) and 3-aminopropyltriethoxysilane (APTES) were selected to modify the hydroxylated boron nitride (BNNS-OH) to obtain a hydrophobic BN@MOF-LDH@APTES. Compared with the previous work, BN@MOF-LDH@APTES demonstrated extremely high filler efficiency in reducing the heat release per unit mass (THR/TM) (18.2 % reduction) and smoke production per unit mass (TSP/TM) (19.1% reduction) of FUPF during combustion. In addition, the obtained FPUF nanocomposite exhibited high absorption capacity while achieving remarkable thermal stability and fire safety. Moreover, the FPUF nanocomposite containing 1 wt% BN@MOF-LDH@APTES achieved a 71% increase in compressive strength, indicating excellent resilience. Therefore, this work provided a new material for the preparation of high-resilience FPUF with both flame retardancy and adsorption capacity.

Exploration on structural rules of highly efficient flame retardant unsaturated polyester resins.

Owing to the lack of research on structure-activity relationship and interaction mechanism between unsaturated polyester resins (UPR) and flame retardants, it has been a big challenge to prepare high-efficiency flame retardants for UPR in industry. In this research, to explore structural rules of high-efficiency flame retardants, several polymeric flame retardants were synthesized with varied main-chain, side-chain, phosphorus valence states and contents of flame retardant elements. The thermal stabilities of flame retardants and UPR composites were firstly assessed. It has been found the interaction existed between flame retardants and UPR, through transesterification reaction and ß scission pathway in polyester and polystyrene chains. With only 15 wt% of PCH3-S, UPR composites can reach V0 rating in UL-94. The PHRR and THR values can be maximumly decreased by 71.66 % and 77.67 %, with 20 wt% of PB-S. It has been found flame retardants with sulfone group and + 3 valence state of phosphorus in molecular backbone can release SO2 and phosphorus containing compounds in gaseous phase, which diluted fuel fragments and catalyzed H⋅ and HO⋅ radical removal. The mechanism for improved flame retardancy of UPR composites with various polymeric flame retardants were discussed in detail. Some general rules for highly efficient flame retardant UPR can be summarized: First, gaseous phase flame retardant mechanism plays the major role in improvement of flame retardant performance of UPR composites; Second, the combination of + 3 valence state of phosphorus structures, higher phosphorus contents and sulfone groups effectively improves the flame retardant efficiency of flame retardants.

Biodegradable L-lysine-modified amino black phosphorus/poly(l-lactide-coε-caprolactone) nanofibers with enhancements in hydrophilicity, shape recovery and osteodifferentiation properties.

Biodegradable poly-(lactide-coε-caprolactone) (PLCL) scaffolds have opened new perspectives for tissue engineering due to their nontoxic and fascinating functionality. Herein, a black phosphorus-based biodegradable material with a combination of promising enhanced hydrophilicity, shape recovery and osteodifferentiation properties was proposed. First, amino black phosphorous (BP-NH2) was prepared by a simple ball milling method. Then, L-lysine-modified black phosphorous (L-NH-BP) was formed by hydrogen bonding between L-lysine and amino BP and integrated into PLCL to form PLCL/L-NH-BP composite fibers. The scaffolds had excellent shape recovery and shape fixity properties. Moreover, based on gene expression and protein level assessment, the scaffolds could enhance the expression of alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP2), simultaneously improving the mineralization ability of bone mesenchymal stem cells. Specifically, this new composite material was experimentally verified to be degradable under mild conditions. This strategy provided new insight into the design of multifunctional materials for diverse applications.

Functionalizing Ti3C2Tx for enhancing fire resistance and reducing toxic gases of flexible polyurethane foam composites with reinforced mechanical properties.

Flexible polyurethane foam (FPUF) is the most used polyurethane, but the highly flammable characteristic limits its widespread usage. In this work, ZIF-8@Ti3C2Txwas synthesized to reduce the heat and toxic gases of FPUF. Flame-retardant FPUF was characterized by cone calorimeter (Cone), thermogravimetric analysis/fourier-transform infrared spectroscopy (TG-FTIR), tensileand compression tests. Compared with pure FPUF, these results showed that the peak of heat release rate (PHRR), total heat release (THR), CO and HCN of FPUF6 decreased by 46%, 69%, 27% and 43.5%, respectively. Moreover, the tensile and compression strength of FPUF6 demonstrated a 52% and 130% increment, respectively. The superior dual metal catalytical charring-forming effect and physical barrier effect of ZIF-8@Ti3C2Tx were achieved. In summary, a simple and reliable strategy for preparing flame-retardant FPUF with reinforced mechanical and fire safety properties was provided.

A facile strategy for lightweight, anti-dripping, flexible polyurethane foam with low smoke emission tendency and superior electromagnetic wave blocking.

Flexible polyurethane foam (FPUF) has been considered as an excellent material in many fields, such as furniture and electromagnetic interference (EMI) shielding products due to its lightweight and flexibility. However, there is a severe fire hazard problem for FPUF that makes it unsuitable to be used in practical. Herein, a facile method was to prepare anti-dripping FPUF via electroless plating at ambient temperature. The silver nanoparticles (SNPs) were in-situ grown on the surface along with the polydopamine (PDA) as an adhesive and template (SNP@PDA@FPUF). As a result, these FPUFs show outstanding fire safety and anti-dripping capacity, and the heat release rate reduced 80.92%. Furthermore, the amounts of carbon oxide (CO) and carbon dioxide (CO2) decreased 75.01% and 22.4%, respectively. Above all, the EMI shielding effectiveness (SE) accomplished almost 120 dB as the increasing electroless time with a low density of 0.051 g/cm3. Furthermore, the specific EMI SE (SSE) and the absolute EMI SE (SSE/t) accomplished 2630.98 dB·cm3/g and 2434 dB·cm2/g, respectively, which was far beyond the commercial request. Therefore, this work may provide a facile way to prepare low density and EMI shielding products with high fire safety for next generation electronic products.

Cattail fibers as source of cellulose to prepare a novel type of composite aerogel adsorbent for the removal of enrofloxacin in wastewater.

In this study, cattail was researched as a natural cellulose source to extract cellulose. Dewaxing, alkali and bleaching treatments were carried out for the cattail fibers (CFs). The FTIR, SEM and XRD results indicated that hemicellulose and lignin were successfully removed from the CFs, and the content of cattail cellulose increased from 41.66 ± 1.11% to 89.72 ± 1.07%. Subsequently, cellulose aerogel was prepared by the extracted cattail cellulose. The Zeolitic imidazolate framework-8 (ZIF-8) was uniformly loaded onto the surface of cellulose aerogel by the in situ growth, and ZIF-8 Cattail Cellulose Aerogel (ZCCA) was finally prepared. The SEM, FTIR, XRD and TGA results further confirmed the successful preparation of ZCCA. Additionally, the results of the adsorption experiment showed that ZCCA had excellent adsorption performance for enrofloxacin, and the maximum adsorption capacity of enrofloxacin reached 172.09 mg·g-1 while showing good reusability. The adsorption process followed the pseudo-second-order kinetic model and the Langmuir isotherm model. Thermodynamic studies showed that the adsorption of enrofloxacin was a spontaneous endothermic reaction and that the adsorption mechanism involves the interaction of hydrogen bonds, electrostatic and π-π stacking.