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In order to solve the problem of low flame retardant efficiency caused by the traditional composite preparation process. Firstly, nano antimony trioxide (nano-Sb2O3) was compounded and modified by cetrimonium bromide(CTAB) and 3-glycidoxypropyltrimethoxysilane(KH560), and then nano-Sb2O3 composites with gradient distribution of nano-Sb2O3 were prepared by utilizing the laminated hot pressing technique. The results show that: CTAB and KH560 are successfully coated on the surface of nano-Sb2O3; the content of the Sb element shows a gradient distribution from top to bottom of the composite section with the pattern of high-low-high. Compared with the homogeneous composites, the flame retardant properties of gradient composites are improved. Among them, the LOI of G828 gradient composite material was increased by 6%. The HRR and SPR of G747, G828, and G909 are higher than those of homogeneous composites at the beginning and the end of combustion, and G828 has the best flame retardant performance among the different gradient structures, with its THR decreasing by 10% and TSP decreasing by 13%. [ABSTRACT FROM AUTHOR]

To improve the flame-retardant property of polybutylene terephthalate (PBT), the ammonium polyphosphate (APP) and the pentaerythritol phosphate (PEPA) were compounded as intumescent flame retardant (IFR). The ball-milled modified attapulgite (mp-ATP) as synergetic flame-retardant was added together with IFR to prepare PBT-based flame-retardant composites. Result that mp-ATP as synergetic flame-retardant improved the flame-retardant effect of IFR to PBT. The addition of IFR decreased the impact strength and tensile strength of PBT. The composite with 9%mp-ATP/13%IFR/PBT had the best comprehensive performance: the peak value of thermal release rate decreased by 27.1% and the total heat release decreased by 31.2%. [ABSTRACT FROM AUTHOR]

Nanoparticles with core-shell structure provide a new potential technology to improve the efficiency of flame retardants. Using nanometer antimony trioxide particles (nano-Sb2O3) as matrix material and brominated bisphenol-A epoxy vinyl ester resin (Br-VERs) diluted by toluene (PhMe) or styrene (ST) as the coating material, PhMe-nano-Sb2O3@Br-VERs and ST-nano-Sb2O3@Br-VERs core-shell composite particles were prepared by electromagnetic stirring method. The results show that Br-VERs can successfully coat on the surface of nano-Sb2O3, thus forming core-shell composite particles with crystalline nano-Sb2O3 as the core and amorphous Br-VERs as the shell. The thickness of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is between 9.5 nm and 15.5 nm, and the shell's mass fraction is 20.8% in the composite particles. The thickness of Br-VERs shell of ST-nano-Sb2O3@Br-VERs composite particles is between 5.5 and 9.5 nm, and the shell's mass fraction is 3.8%. The mass of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is 5.47 times that of ST-nano-Sb2O3@Br-VERs composite particles, which indicates PhMe used as the diluent for Br-VERs has a better effect than that of ST used as the diluent. [ABSTRACT FROM AUTHOR]

AbstractTo improve the epoxy bonding properties of polyphenylene sulfide (PPS) matrix composites, CK-MMT and K-BF were prepared by modifying montmorillonite (MMT) and basalt fiber (BF) with cetyl trimethyl ammonium bromide (CTAB) and 3-Glycidyloxypropyltrimethoxysilane (KH-560) as the modifiers. CK-MMT/BF/TPU/PPS composites were prepared by injection moulding. The surface properties of the composites were tested and characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), etc. The epoxy bonding and mechanical properties were studied by combining the single-lap-joint tensile shear strength test and notched impact test. The results demonstrated the successful preparation of the modified MMT and BF. With the addition of CK-MMT and K-BF in different ratios, the surface roughness and the contents of polar groups of the composites increased, which could effectively improve the epoxy bonding properties of PPS matrix composites. When the additions of CK-MMT and K-BF were 10 and 25 wt%, respectively, the composites had the best overall properties. It demonstrated a single-lap-joint tensile shear strength was 7.56 MPa, representing a 220.34% increase over that of thermoplastic polyurethane/polyphenylene sulfide (TPU/PPS) and a 477.10% increase over that of pure PPS. [ABSTRACT FROM AUTHOR]

Poor dispersion of nanoparticles in polymer matrix would limit the development and application of particulate-filled polymer composites. Therefore, the Sb2O3 nanoparticles were functionalized by a combination of cetyltrimethyl ammonium bromide (CTAB) and silane coupling agent KH-560 via water bath modification method so as to improve the dispersion of Sb2O3 nanoparticles in poly(butylene terephthalate) (PBT) matrix and enhance the interfacial adhesion between nanoparticles and polymer matrix. Besides, the coating efficiency of compound modifiers on the surface of Sb2O3 nanoparticles was characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA). The Sb2O3 nanoparticles with different morphologies were systemically measured using transmission electron microscopy and dynamic light scattering measurement. The effects of particle surface treatment, particle size, particle morphology and particle loading on mechanical properties of composites were studied by the X-ray diffraction (XRD), tensile test machine and impact strength machine. The tensile strength of nanocomposites gradually increases with decreasing the particle size at the same amount of Sb2O3 nanoparticle fillers, which is attributed to improvement of interfacial contact area and stronger interfacial adhesion between Sb2O3 nanoparticles and PBT matrix. And the compound modified Sb2O3 nanoparticles are homogeneously dispersed in PBT matrix and play an important role in the properties enhancement. Moreover, taking consideration of the tensile and impact strengths, the optimal loading is 3 wt%. [ABSTRACT FROM AUTHOR]