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Acoustic materials embed with inorganic fillers in viscoelastic polymers have promising applications in industrial settings. However, optimizing the sound insulation of composites by adjusting the microstructure of nanofillers remains a challenge. In this study, we synthesize adjustable hollow hierarchical Zeolite Socony Mobil #5 (ZSM‐5) which can be used as nanofillers in a sound insulation nanocomposite based on the polyacrylate (PA). The results show that the nanocomposites with 0.5 wt% hierarchical hollow ZSM‐5 can increase the sound transmission loss (STL) by 33.4%. The maximum STL value reaches as high as 40 dB. The damping properties of the nanocomposites were also improved by adding ZSM‐5 into the PA matrix. When the loading of hollow ZSM‐5 is 0.5 wt%, the storage modulus increased by 44%, as high as 4486.7 MPa. This strategy opens up a promising way for the sound insulation of composites based on controllable inorganic nanofillers. [ABSTRACT FROM AUTHOR]

The epoxy/silica nanocomposites containing a wide range of isopropyltri[di(octyl) phosphate] titanate coupling agent (KR‐12) modified nanosilica (m‐nanosilica) loading (0–7 wt%) cured with tetrabutyl titanate hardener were prepared. Their morphology, thermal stability, thermal expansion, and mechanical properties including hardness, abrasion resistance were investigated. The wetting ability of epoxy‐nanosilica systems on glass surface was assessed based on static contact angle. The obtained results showed that the contact angle of the nanocomposites containing m‐nanosilica is slightly changed as compared to the contact angle of pure epoxy resin and lower than that of the nanocomposite containing unmodified nanosilica. The data of dynamic mechanical analysis of the nanocomposites using different nanosilica content indicated that the presence of m‐nanosilica lowered the recovery energy of the nanocomposites to 41.62% as compared to neat epoxy. The limiting oxygen index (LOI) of the nanocomposites confirmed that the m‐nanosilica increased the flame retardance of epoxy matrix. When using 7 wt% of m‐nanosilca, the LOI value of the nanocomposite was 27.4 while this index of neat epoxy was 21.6. The scanning electron microscopic images of residual char combustion of the nanocompsites indicated a formation of nanosilica layer contributed to restrain combustion of the material. [ABSTRACT FROM AUTHOR]

In this article, a flame retardant microcapsule ammonium polyphosphate microencapsulated by polyurea (POAPP) was successfully synthesized by interfacial polymerization method using ammonium polyphosphate (APP) as core and polyurea as shell. The microencapsulation is observed by scanning electron microscopy and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and hydroscopicity test, which prove the success in synthesizing microencapsulation. When the POAPP is added into rigid polyurethane foam (RPUF), the flame retardant and mechanical properties are investigated using cone calorimeter, limited oxygen index test, and compressive strength test. The PHRR of RPUF‐POAPP20 decreased from 336.52 kW/m2 (Ref. RPUF) to 203.84 kW/m2 and the THR of RPUF‐POAPP20 was only 7.6 MJ/m2, which is 33.9% lower than that of Ref. RPUF. Furthermore, the limiting oxygen index of RPUF‐POAPP20 reaches 24.8%, which increased by 36.3% compared to Ref. RPUF. Whereas the maximum compressive strength of RPUF‐POAPP5 was 7.46 MPa, which is higher than that of RPUF‐APP5. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, the smoke production behaviors of crosslinked epoxy/polyamide resin (EP/PA) and intumescent fire retardant (IFR) in epoxy-based intumescent fire-retardant coating (IFR-EP) have been investigated using cone calorimeter, smoke density instrument, and thermogravimetric analysis and Fourier transform infrared spectroscopic measurement. The static and dynamic smoke production behaviors of EP/PA and IFR-EP indicate that the IFR has an excellent smoke suppression effect on EP/PA by forming protective char layer in the late combustion stage, while the epoxy crosslinked structure in IFR-EP can enhance the thermal stability and reduce smoke production in the early combustion stage. In addition, according to the discussion of pyrolysis gas products, the IFR can effectively suppress the production of toxic and inflammable gases during the combustion process. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43912. [ABSTRACT FROM AUTHOR]

Ammonium polyphosphate (APP) is an effective phosphorus‐containing flame retardant. But APP also has excellent hygroscopic capacity and decreases the mechanical property of composite. The aim of the study was to microencapsulate APP with polymethyl methacrylate (PMMA) to prepare microencapsulated ammonium polyphosphate (PMAPP) in order to eliminate the harmful effects caused by the mechanical property of composite. The microcapsules are characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), and hydroscopicity test and observed by scanning electron microscopy (SEM). Fire hazard of rigid polyurethane foam (RPUF) is evaluated using a cone calorimeter and limited oxygen index test. The mechanical property of RPUF is studied by compressive strength test. The results show that APP has been microencapsulated by PMMA successfully and the shell does not decrease the beneficial effect of APP on fire hazard of RPUF. Furthermore, the shell also reduces the damage of APP on the mechanical property of composite. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48307. [ABSTRACT FROM AUTHOR]