The promising indicators of the thermal and mechanical properties of collagen from bass and tilapia: synergistic effects of hydroxyproline and cysteine

AbstractThis work aims to study the synergistic effect of aluminum/magnesium hydroxide microfillers and organomodified fumed silica nanoparticles as flame retardants (FRs) for linear low-density polyethylene (LLDPE), and to select the best composition to produce a fire-resistant polyethylene-based single-polymer composite. The fillers were added to LLDPE at different concentrations, and the prepared composites were characterized to investigate the individual and combined effects of the fillers on the thermo-oxidation resistance and the fire performance, as well as the microstructural, physical, thermal and mechanical properties. Both filler types were homogeneously distributed in the matrix, with the formation of a network of silica nanoparticles at elevated loadings. Melt flow index (MFI) tests revealed that the fluidity of the material was not considerably impaired upon metal hydroxide introduction, while a heavy reduction of the MFI was detected for silica contents higher than 5 wt%. FRs introduction promoted a noticeable enhancement of the thermo-oxidative stability of the materials, as shown by thermogravimetric analysis (TGA) and onset oxidation temperature (OOT) tests, and superior thermal properties were measured on the samples combining micro- and nanofillers, thus evidencing synergistic effects. Tensile tests showed that the stiffening effect due to a high content of metal hydroxide microparticles was accompanied by a decrease in the strain at break, but nanosilica at low concentration contributed to preserve the ultimate mechanical properties of the neat polymer. The fire performance of the samples with optimized compositions, evaluated through limiting oxygen index (LOI) and cone calorimetry tests, was strongly enhanced with respect to that of the neat LLDPE, and also these tests highlighted the synergistic effect between micro- and nanofillers, as well as an interesting correlation between fire parameters and viscosity.

Download Full-text

The Synergistic Effect of Flame Retardants on Flammability, Thermal and Mechanical Properties of Natural Fiber Reinforced Epoxy Composite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.701.281 ◽

2016 ◽

Vol 701 ◽

pp. 281-285 ◽

Cited By ~ 1

Author(s):

Pooria Khalili ◽

Kim Yeow Tshai ◽

Ing Kong ◽

Jun Hui Lee ◽

Farzad Arefi Mostafa

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Mass Loss ◽

Heat Release ◽

Natural Fiber ◽

Synergistic Effects ◽

Epoxy Composites ◽

Zinc Borate ◽

Thermal And Mechanical Properties ◽

Combustion Heat

Epoxy was effectively resin infused with 15 %wt intumescing Alumina Trihydrate (ATH) flame retardant (FR) formulations into a 10 %wt palm EFB natural fiber (NF) mat. The effects of ATH and its intumescing blend with Zinc Borate (ZB) and Ammonium Polyphosphate (APP) on flammability, thermal and mechanical properties of the composites were investigated. Compared to neat NF filled epoxy composites, specimens loaded with intumescing blend of FR formulations demonstrated an improved thermal properties, showing greater mass residual which can be attributed to the formation of cross-linked network amongst the NF, FRs and epoxy matrix upon combustion at elevated temperature tested within a TGA instrument. Incorporation of fibers drastically enhanced the mass residue and lowered the heat release compare to the pure epoxy. Addition of the intumescing blend of FR formulations also drastically reduces the combustion heat release, total mass loss and zero drip flame in the NF composites. The optimum FRs formulation with 5 %wt ATH and 10 %wt APP exhibited self-extinguishing property, achieved lowest mass loss and no drip flame under Bunsen burner tests, signifying the synergistic effects between ATH and APP within the NF epoxy composites. APP reacts with the carbonaceous network of NF throughout the ignition period, such interaction formed a thick char layer acting as gas and thermal barrier against the fire mechanism. This reaction does not take place in NF composite specimens without APP. In terms of mechanical properties, NF composites loaded with FRs broadly showed poorer tensile strength, mainly due to the existence of FRs, which acted as a nucleating agent affected the physico-mechanical characteristics of the composites. Amongst the FR rich formulations, specimens with APP or ZB blends seem to possess a more superior tensile strength compared with the neat ATH filled formulation. In addition, composites loaded with FRs showed enhanced Young’s modulus relative to those without addition of FRs.

Download Full-text