Reinforcement of recycled PP polymers by nanoparticles incorporation

Rare earth/polypropylene (PP)/thermoplastic polyurethane (TPU) fibers were prepared by melting spinning with different mass ratios of PP to TPU. Then the rare earth/TPU shielding fiber was obtained by removing the PP matrix phase from the blend fiber using xylene. The fibers were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), thermogravimetric analyzer (TG), and scanning electron microscopy (SEM). Short fibers were compressionmolded for the test of lead equivalent. The results showed that the lead equivalent of the rare earth/TPU composite fibers was 0.19 mmPb when the mass ratio of PP/TPU increased to 60/40. At this mass ratio, the X-ray shielding performance of the fiber was the best.

“…The weight loss of the stage B is due to the decomposition of PP. In this process, the urethane groups were broken first and then the alkane chain …”

Section: Resultsmentioning

confidence: 99%

Preparation and structure of rare earth/thermoplastic polyurethane fiber for X‐ray shielding

Lou

Teng

Jia

et al. 2018

“…Recently, Zdiri et al . reviewed the effect of selected nanofillers on the mechanical, thermal, and rheological properties of recycled polypropylene and it was pointed out that the silica nanoparticles can improve the thermal stability of polypropylene.…”

Section: Introductionmentioning

confidence: 99%

“…Recently, Zdiri et al 28 reviewed the effect of selected nanofillers on the mechanical, thermal, and rheological properties of recycled polypropylene and it was pointed out that the silica nanoparticles can improve the thermal stability of polypropylene. SiO 2 -NH 2 nanoparticles, when used in the PP/IFR system at 1 wt %, improved the thermal stability and increased the LOI of the composites significantly.…”

Section: Introductionmentioning

confidence: 99%

Flame‐retardant effects of cyclic phosphonate with HALS and fumed silica in polypropylene

Üreyen

Kaynak

Yüksel

2019

In this study, an N‐alkoxy‐hindered amine‐based UV stabilizing agent (NOR‐116) and nanosized silica particles (Aerosil R‐972) were combined with a cyclic phosphonate based‐flame retardant (FR; PCO‐900) and incorporated into polypropylene via melt extrusion in a microcompounder. In order to stimulate the conditions in the favor of further processing such as fiber spinning, the content of additives in polypropylene was kept low (up to 6.5 wt %). The effects of the PCO‐900, alone and in combination with NOR‐116 and Aerosil‐R972, on the flammability and thermal stability of polypropylene were evaluated by limit oxygen index (LOI) tests, cone calorimetry, and thermogravimetric analysis. The proposed system with 3.5 wt % PCO‐900/1.5 wt % NOR‐116/1 wt % Aerosil‐R972 decreased the heat release, increased the LOI and thermo‐oxidative stability, and, thus, improved the fire resistance of polypropylene. The possible mode of FR activity was also discussed based on the analysis. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48308.

“…Polymerization of DMAA or NIPAM in aqueous Laponite dispersions leads to the formation of water‐stable, highly stretchable hydrogels due to the action of clay nanoparticles as dynamic multifunctional crosslinks with large effective functionality . Similar to the polymers such as polypropylene reinforced by nanoparticles, increasing amount of Laponite also increases the mechanical strength and toughness of NC hydrogels.…”

Section: Introductionmentioning

confidence: 99%

Hydrophobically modified nanocomposite hydrogels with self‐healing ability

Akca

Yetiskin

Okay

2019

Several strategies have been developed in the past two decades to increase the mechanical performance of the hydrogels, and to generate self-healing function within the polymer network. Here, we combine two of these strategies to create hydrophobically modified nanocomposite (NC) hydrogels with high mechanical strength and self-healing efficiency. The hydrogels were prepared by in situ copolymerization of N,N-dimethylacrylamide and n-octadecyl acrylate (C18A) in the presence of 2 w/v % Laponite clay nanoparticles in an aqueous solution of worm-like sodium dodecyl sulfate micelles. Incorporation of hydrophobic C18A segments into the gel network significantly increases both the storage and loss moduli of NC hydrogels indicating increasing elasticity and energy dissipation. An improvement in the mechanical performance and self-recoverability of NC hydrogels was also observed after hydrophobic modification. The compressive fracture stress and Young's modulus increase with increasing amount of C18A, and they become 9 AE 1 MPa and 30 AE 2 kPa, respectively, at 4 mol % C18A. Incorporation of hydrophobic segments also provides a larger energy dissipation under large strain as compared to the traditional NC hydrogels providing a self-healing efficiency of 90 AE 10% in mechanically strong NC hydrogels.