Natural-fiber-reinforced polypropylene (PP) composites with a series of advantages including light weight, chemical durability, renewable resources, low in cost, etc., are being widely used in many fields such as the automotive industry, packaging, and construction. However, the flammability of plant fiber and the PP matrix restricts the application range, security, and use of these composites. Therefore, it is of great significance to study the flame retardants of such composites. In this paper, sisal-fiber-reinforced polypropylene (PP/SF) flame-retardant composites were prepared using the two-step melt blending method. The flame retardant used was an intumescent flame retardant (IFR) composed of silane-coated ammonium polyphosphate (Si-APP) and pentaerythritol (PER). The influence of different blending processes on the flammability and mechanical properties of the composites was analyzed. The findings suggested that PP/SF flame-retardant composites prepared via different blending processes showed different flame-retardant properties. The (PP/SF)/IFR composite prepared by PP/SF secondary blending with IFR showed excellent flame-retardant performance, with a limited oxygen index of about 28.3% and passing the UL-94 V-0 rating (3.2 mm) in the vertical combustion test. Compared with the (PP/IFR) /SF composite prepared by a matrix primarily blended with IFR and then secondly blended with SF, the peak heat release rate (pk HRR) and total heat release (THR) of the (PP/SF)/IFR composite decreased by 11.3% and 13.7%, respectively. In contrast, the tensile strength of the (PP/SF)/IFR system was 5.3% lower than that of the (PP/IFR)/SF system; however, the overall mechanical (tensile, flexural, and notched impact) properties of the composites prepared using three different mixing processes were similar.

Ammonium polyphosphate (APP) was successfully modified by a titanate coupling agent which was compounded with benzoxazine (BOZ) and melamine (ME) to become a new type of intumescent flame retardant (Ti-IFR). Ti-IFR and CaCO3 as synergists were utilized to modify polyoxymethylene (POM), and the flame-retardant properties and mechanism of the composites were analyzed by vertical combustion (UL-94), limiting oxygen index (LOI), TG-IR, and cone calorimeter (Cone), etc. The results show that Ti-IFR can enhance the gas phase flame retardant effect, while CaCO3 further strengthens the barrier effect in the condensed phase. When they were used together, they can exert their performance, respectively, at the same time showing excellent synergistic effect. The FR-POM composite with 29% Ti-IFR and 1% CaCO3 can pass the UL-94 V0 level. The LOI reaches 58.2%, the average heat release (Av HRR) is reduced by 81.1% and the total heat release (THR) is decreased by 35.3%.

A novel intumescent flame retardant (IFR) composed of ammonium polyphosphate (APP), benzoxazine containing trialkoxysilane (BA‐a‐Si) and melamine (ME), is compounded with different specifications of MoS2 as synergist to flame retard polyformaldehyde (POM). The flame retardancy and mechanism of the composites are analyzed by limiting oxygen index (LOI), vertical combustion (UL‐94) and cone calorimeter. At the same time, the mechanical properties and lubricating properties are tested by electromechanical testing machine and wear testing machine. The experimental results show that MoS2 has a good synergistic effect with IFR, and the smaller the average particle size of MoS2 is, it seems to be more beneficial to improve the flame retardancy of POM composites. Only a small amount of MoS2 (0.8 wt%) is needed to synergize with IFR, the flame retardant POM composite (FR‐POM) can achieve UL‐94 (3.2 mm) V‐0 rating, LOI of 62.5%, and heat release rate reduction of 25.3%, total smoke release decreased by 29.5%. In addition, from the mechanical properties analysis, it is found that the microscale MoS2(M2) can better improve the bending and tensile properties of the FR‐POM composites, while the nanoscale MoS2(N80) is more helpful to improve the lubricating properties.

Endometrial cancer (EC) is one of the most common gynecological malignancies. The aim of this study was to evaluate the combined prognostic value of D-dimer and fibrinogen in EC patients. We evaluated the prognostic value of preoperative plasma fibrinogen and D-Dimer concentration in EC patients using Kaplan-Meier curve analysis and Cox proportional hazards regression model. Kaplan-Meier curve analysis demonstrated that EC patients with higher levels of plasma fibrinogen or D-Dimer had a significantly poorer overall survival (OS) and recurrence-free survival (RFS). Furthermore, combination of fibrinogen and D-Dimer levels significantly improved the efficacy for predicting RFS of EC patient. Patients with higher fibrinogen or D-Dimer levels exhibited a significantly poorer RFS in both the univariate and multivariate analysis. In conclusions, the preoperative plasma fibrinogen and D-Dimer concentrations may serve as potential prognostic factors for EC patients, and combination of fibrinogen and D-Dimer concentration may be a potential marker for predicting RFS of EC patients.