A series of novel phosphaphenanthrene/ phenylsiloxane bigroup macromolecules (DDSi-n) were synthesized and applied to obtain high-performance epoxy thermosets. DDSi-n macromolecules simultaneously enhanced the anti-impact and flame-retardant performance of epoxy thermosets. The impact strength of the DDSi-n-containing thermoset (DDSi-n/EP) was maximally increased by nearly 140% in 8% DDSi-1/EP because of the flexible phenylsiloxane block and the polar phosphaphenanthrene group interacting with matrix in DDSi-n macromolecules. Meanwhile, the evidently elevated anti-ignition and self-extinguishing performance, the suppressed combustion heat, and the enhanced charring capability of DDSi-n/EP were all caused by the flame-retardant group synergistic effect of phosphaphenanthrene and phenylsiloxane groups of DDSi-n macromolecules in thermosets. Compared with the individual phosphaphenanthrene or phenylsiloxane group in monogroup contrasts, the phosphaphenanthrene and phenylsiloxane groups in bigroup DDSi-n macromolecules were disclosed to synergistically work to toughen and flame-retard epoxy thermosets more efficiently. The working results of bigroup DDSi-n macromolecules in thermosets reveal a superior way to construct high-performance materials.

An aromatic macromolecular polyimide (API) was synthesized and characterized, and used as a synergistic charring flame retardant in glass fiber reinforced polyamide 6 (GF/PA6). API and aluminum diethylphosphinate (ADP) exhibited better flame inhibition behavior and synergistic charring flame retardant behavior compared with ADP alone. The 5%API/7%ADP/GF/PA6 sample achieved the lower peak value of the heat release rate (pk-HRR) at 497 kW/m2 and produced higher residue yields of 36.1 wt.%, verifying that API and ADP have an outstanding synergistic effect on the barrier effect. The API/ADP system facilitated the formation of a carbonaceous, phosphorus and aluminum-containing compact char layer with increased barrier effect. FTIR spectra of the residue and real-time TGA-FTIR analysis on the evolved gases from PA6 composites revealed that API interacted with ADP/PA6 and locked in more P–O–C and P–O–Ar content, which is the main mechanism for improving flame inhibition and charring ability. In addition, the API/ADP system improved the mechanical properties and corrosion resistance of GF/PA6 composites compared to ADP alone.

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To meet the increasingly stringent requirements for the excellent fire safety, low addition, low cost, and good mechanical properties for polycarbonate (PC), a novel aromatic polyimide (API) charring agent was synthesized and used synergistically with hexaphenoxycyclotriphosphazene (HPCTP) to flame‐retardant (FR) PC. The incorporated API and HPCTP improved FR performance and the fracture toughness of the PC, simultaneously. The 4H‐2A passed the UL94 V‐0 rating with a limited oxygen index of 32.5%. Moreover, the heat release rate of the PC was also suppressed significantly by the dense and strengthening carbon layer. The mechanism of synergistic charring effect of API and HPCTP were analyzed: In the initial and developing stages of combustion (below 450°C), the quenching effect and dilution effect of HPCTP played a major role in flame retardancy; and due to the barrier function of the highly graphitized char layer, the combustion process rapidly enters weakening stages (above 450°C) and finally extinguishes. Moreover, it was founded that API improved the antiimpact performance of PC matrix, which offsets the negative effect of HPCTP on the impact performance of PC matrix.

This work aimed to determine the influence of superfine grinding on the physicochemical properties of bulbs of Fritillaria unibracteata Hsiao et K.C. Hsia (BFU) powder. For this purpose, fine powder (FP) and two superfine powders (SPs) were obtained via superfine and conventional grinding methods. The properties of different powders were studied and compared. Compared with FP, SPs exhibited higher values in terms of the angle of repose, swelling capacity, ethanol extraction yield, total alkaloid content, and imperialine content, while lower values in terms of particle size and bulk density. Especially, the total alkaloid content of SP‐I increased by 66.7%. Proper grinding is more conducive to reduce particle size and improve alkaloid content. FTIR analysis indicates that no new functional groups produced after superfine grinding. XRD analysis suggests that grinding treatment lead to decreases in the crystallinity. Therefore, superfine grinding displays immense potential in the BFU application.