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Hybrid composites composed of bio-based thin-ply carbon fibre prepreg and flame-retardant mats (E20MI) have been produced to investigate the effects of laminate design on their fire protection performance and mechanical properties. These flame-retardant mats rely primarily on expandable graphite, mineral wool and glass fibre to generate a thermal barrier that releases incombustible gasses and protects the underlying material. A flame retardant (FR) mat is incorporated into the carbon fibre bio-based polymeric laminate and the relationship between the fire protection properties and mechanical properties is investigated. Hybrid composite laminates containing FR mats either at the exterior surfaces or embedded 2-plies deep have been tested by the limited oxygen index (LOI), vertical burning test and cone calorimetry. The addition of the surface or embedded E20MI flame retardant mats resulted in an improvement from a base line of 33.1% to 47.5% and 45.8%, respectively. All laminates passed the vertical burning test standard of FAR 25.853. Cone calorimeter data revealed an increase in the time to ignition (TTI) for the hybrid composites containing the FR mat, while the peak of heat release rate (PHRR) and total heat release (TTR) were greatly reduced. Furthermore, the maximum average rate of heat emission (MARHE) values indicated that both composites with flame retardant mats had achieved the requirements of EN 45545-2. However, the tensile strengths of laminates with surface or embedded flame-retardant mats were reduced from 1215.94 MPa to 885.92 MPa and 975.48 MPa, respectively. Similarly, the bending strength was reduced from 836.41 MPa to 767.03 MPa and 811.36 MPa, respectively. [ABSTRACT FROM AUTHOR]

This research work presents the results obtained from a comparative corrosion evaluation of welded joints on uncoated steel in flat position, welded joints in flat position on steel protected with polymeric film, and welded joints in flat position on steel covered with nanocomposite polymeric film (primer reinforced with TiO2 nanoparticles). The electrochemical methods of open circuit potential, linear polarization resistance, and electrochemical impedance spectroscopy were used for corrosion evaluation. The results of the electrochemical tests indicate that titanium oxide reinforcing polymeric film to form nanocomposite layers over naval welded steel increases the corrosion protection of polymeric film as compared with unmodified primer. [ABSTRACT FROM AUTHOR]

A facile and effective method to prepare novel phosphorylated amino graphene oxide (PA-GO) fire retardant material was discussed in this report. PA-GO was prepared using graphene oxide nanoparticle, (3-aminopropyl)trimethoxysilane (APTMS), formaldehyde, and hypophosphorous acid. PA-GO imparted excellent fire retardancy to the fabric when applied on cotton fabric by a dip coating method. The PA-GO coated cotton fabric (CT PA-GO) was tested using various characterization techniques to understand its morphology, composition, thermal stability, and combustion nature. When cotton fabric (control) and CT PA-GO (coated fabric) were exposed to a flame, control fabric burned rapidly producing ash, whereas coated fabric released little smoke at start but did not ignite and maintained its original shape and size even after exposing to flame for >160 s. The PA-GO coating cross-linked with cotton fabric at higher temperature formed thermally stable structure and opposed the exposure of fire to the underlined fibre. The limiting oxygen index (LOI) value for the coated fabric was 32.3 % as compared to the control sample 17.9 %. The tensile strength of the fabric was retained effectively after PA-GO treatment. Pigment acrymine binder paste was used to improve the durability of the coating on fabric inside water, which helped in maintaining the fire retardant properties after water soak test. [Display omitted] • Novel phosphorylated amino graphene oxide (PA-GO) was synthesized for fire retardant coating. • PA-GO was prepared via simple method and then dip-coated onto cotton fabric. • PA-GO coated fabric increased LOI to 32.3 % and reduced char length to 5.1 cm during VFT. • CT PA-GO with binder had lower weight loss during water soak test and maintained fire retardancy. • Coated fabric has huge potential to design advanced fire-retardant fabrics in textile industries. [ABSTRACT FROM AUTHOR]

Three dimensional (3D) graphene aerogel was prepared by in situ reduction-assembly method. Paraphenylene diamine (PPD) was used as reducing and functionalizing agent of graphene oxide in an aqueous medium with ammonia. The synthesized 3D graphene-PPD aerogel has highly porous structure, low density, high electrical conductivity and good mechanical properties. Further, epoxy/aerogel composites were prepared by vacuum-assisted impregnation process, which exhibited good electrical conductivity and compressive properties. [ABSTRACT FROM AUTHOR]