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Polymers are widely employed in many areas, e.g. transport, packaging, electronic devices, etcetera. Among them, acrylonitrile–butadiene–styrene (ABS) is one of the most employed polymers due to its mechanical properties, its ease to mechanize and recyclability. Nevertheless, according to the fire properties, ABS behaviour is usually worse than other polymers, therefore, they have to be upgraded with flame retardant additives. To characterize the fire behaviour of a certain material is necessary to address several typology of tests, providing relevant properties such as thermal conductivity, flammability and heat released. However, researchers may not always be able to run all tests due to the lack of apparatus or samples. Therefore, it is necessary to seek bibliographic sources. As one might expect, for a given material, the property values should be similar, regardless of who performs the test. However, sometimes slightly different results are obtained, which may be due to different causes, such as differences in test set-up and in material composition/manufacture. These differences in properties may lead researcher to doubt which data to use. This paper presents the results of different types of tests using neat ABS polymer. Additionally, these results are compared with the data from literature, discussing the similarities/differences and offering a more comprehensive characterization of ABS. The laboratory techniques included in this work are: thermogravimetric analysis, differential scanning calorimetry, laser flash analysis, smoke density, cone calorimeter, fire propagation and flammability. [ABSTRACT FROM AUTHOR]

The cellulose (Cel)-polyvinyl alcohol (PVA)-sodium alginate (SA) composite aerogels are prepared by adding PVA and SA to the Cel suspension, followed by freeze-drying. The structure and properties of Cel-PVA-SA composite aerogels are determined by FT-IR, scanning electron microscopy, thermogravimetric analysis, limiting oxygen index method and cone calorimetry. The results reveal that sodium alginate is uniformly distributed within the aerogels. The as-synthesized composite aerogels possess excellent compressive resilience properties. In addition, the addition of sodium alginate significantly reduces the flammability of cellulose. Therefore, this study provides a simple method to prepare green flame-retardant Cel-PVA composite aerogels materials, and the aerogels demonstrate excellent potential for application in construction materials. [ABSTRACT FROM AUTHOR]

Currently, the issue of natural flammability of unsaturated polyester resin (UPR) severely restrains its application. In this study, polymeric flame retardant poly methyl vinyl di (1-thio-2,6,7-trioxal-1-phosphabicyclo [2.2] octane-4-methoxy) silane (PMVDOS) with P–S–Si-based cage unit was synthesized. The UPR/PMVDOS composites were prepared by adding different ratios of PMVDOS into UPR. The flame-retardant properties and the char layer structure of UPR samples were evaluated via the limiting oxygen index (LOI), vertical burning test, cone calorimeter test, scanning electron microscopy, laser Raman spectroscopy, and X-ray photoelectron spectroscopy. The results showed that UPR/PMVDOS composites reached the UL-94 V-0 rating with the LOI value of 27.8%, and the carbon residue increased from 4.9% for pure UPR to 14.9% when the content of PMVDOS was 18 wt%. The peaks of heat release rate, total heat release, and total smoke production were comparatively reduced. The flame-retardant mechanism of PMVDOS mainly acted on the condensed phase. The surface of the matrix was covered with the polymer containing phosphorous and silicon dioxide particles, preventing the escape of flammable volatiles and isolating the exchange of oxygen and heat, thus, the degradation of the matrix could be inhibited. This research provides a solution to improve the flame retardancy of UPR. [ABSTRACT FROM AUTHOR]

This study focuses on the synergistic effects of hydroxide based nanoparticles namely aluminum trihydrate (ATH) and zirconium hydroxide (ZHO) on the mechanical characteristics, thermal stability, and flammability of polyester/jute composite material. Polyester/jute composites were fabricated by incorporating different concentrations of both ATH and ZHO nanoparticles (2, 3 and 4 wt%). The weight of jute fabric in all composite has been kept as 40%. The results showed a significant enhancement in tensile, flexural and impact properties of polyester/jute composite after the inclusion (3 wt%) of either type of nanoparticles. The improvement in the mechanical properties is attributed to the existence of OH interaction between ATH, ZHO, and jute fabric, which has been verified through FTIR spectroscopy. The compatibility of the nanoparticles also lead to improved interfacial bonding, which has been discussed after the scanning electron microscopy of the fractured surfaces. An increase in the thermal stability of the composites was also observed through thermogravimetric analysis. Cone calorimetry and horizontal burning tests showed significant enhancement in the fire retardancy of the developed composites due to endothermic decomposition of ATH and ZHO nanoparticles into char layer and water molecules during combustion, contributing strong resistance to heat, oxygen and flammable gases. The synergistic effect of both ATH and ZHO particles enhances mechanical, thermal, and fire retardant properties of polyester/jute composites. [ABSTRACT FROM AUTHOR]