Effects of calcium stearate and metal hydroxide additions on the irradiated LDPE/EVA compound properties

Abstract

The effects of the addition different fillers, such as calcium stearate (CS), aluminum trihydrate (ATH), and magnesium hydroxide (MH), on the properties of lowdensity polyethylene/ethylene vinyl acetate (LDPE/EVA) compounds were studied. It was determined that the adhesion forces among MH and LDPE/EVA compounds were stronger than those among analogue compounds containing ATH in each irradiated sample. The gel content (GC) values of irradiated compounds containing ATH were higher than those of the analogue MH compounds, and CS addition enhanced the GC values of all compounds in each irradiated sample. The density values of compounds with MH content were higher than those of analogue compounds containing ATH in each irradiated sample. It was shown that all pristine compounds whose density was compared with irradiated samples had maximum values. Addition of CS and enhancing irradiation to polymer compounds reduced the density values. Compounds with high CS contents and were highly irradiated showed high tensile strength (TS) values. The TS values of compounds containing ATH were lower than those of analogue compounds containing MH in each irradiated sample. ATH or MH addition to polymer matrices reduced the elongation at break (EB) values in each irradiated sample. The EB values of compounds containing ATH were higher than those of compounds containing MH in each irradiation range. CS addition improved polymer chain flexibility and enhanced the compounds' EB values with irradiation.

Effect of addition graphene to ethylene vinyl acetate and low‐density polyethylene

“…The initial thermal degradation of pure EVA happens between 290 and 360°C as acetate groups decompose to CO 2 . The second degradation owes to degradation of main polyethylene chains; in pure EVA, it takes place between 370 and 715°C . This degradation in composite with 0.5 and 1 wt% of Gr is very alike to that of pristine EVA.…”

“…The variations between routine strengthening and nanoscale fillers are described by a decrease in nanoparticles' dimensions that grows surface areas in interaction with the polymeric matrix, creating so‐called “nanoeffects” in composite configuration . A composite is a material which one of its elements has one nanometric aspect, and is recognized through three various classifications: Zero‐dimensional like metal and ceramic nanoparticles. Mono‐dimensional like carbon nanotubes (CNTs) and inorganic nanowires. Bi‐dimensional like nanoclay and Grs . …”

Broad studies of graphene and low-density polyethylene composites

“…Upgrading is elucidated by barrier impact of Grs that is concluded in an upgrading of resistance to thermal decomposition and thus in delaying the diffusion of degradation products from LDPE onto gas phase. [20][21][22][23][24][25][26][27][28][29][30][31][32][33] This strength is related to better interfacial interactions among nanofillers and LDPE and also fine distribution of nanofillers in LDPE that directed to a growth in activation energy for thermal decomposition. [11][12][13][14][15][16][17][18] LDPE/Gr composites present a great thermal property.…”

“…The heterogeneous nucleation also produces higher T m values for LDPE/Grs, because more Gr concentration prepares more nucleation locations and cause quicker growing speed for polymers. [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] Consequently, a crystallinity of LDPE/Grs is also developed. Relative crystallinity as a variable of temperature for LDPE and composites is displayed in Figure 17.…”

“…The high-level aspect ratio of nanofillers and powerful interaction at the boundary of filler-LDPE are two important elements essential to improving the mechanical operation of LDPE composites. [20][21][22][23][24][25] [26][27][28][29][30][31] ; third reason, Gr has large aspect ratio and specific surface area and its contact geometry is two dimensional (surface) which results from better interfacial stress transfer between Grs and LDPE. [28][29][30][31][32][33][34][35][36] The dynamic behavior of the composite is studied with dynamic mechanical analysis (DMA Figure 24.…”