Mechanical and thermal properties of coal gasification fine slag reinforced low density polyethylene composites

Abstract

Coal gasification fine slag (CGFS) was processed via a grading technique. The CGFS products (CGFS-S1, CGFS-S2, CGFS-S3) with different sizes were obtained. Effects of particle size and unburned carbon on tensile properties of filled low density polyethylene (LDPE) were studied within the CGFS weight fractions ranging from 10 to 50 wt %. The tensile strength was found to increase with decreasing CGFS size, and the tensile properties exhibited good performance, owing to unburned carbon. The tensile strength of the composites increased with increasing CGFS-S3 weight fraction. The analysis of mathematical model and SEM revealed that the firm improvement of tensile strength resulted from the strong interactions between LDPE polymer chains and CGFS-S3 particles, and good dispersion of CGFS-S3 in resin. Thermogravimetric analysis proved obvious reinforcement in thermal-oxidative stability by incorporation of CGFS-S3. The degree of crystallinity of LDPE/CGFS-S3 showed the first increased and then decreased variation tendency.

Mechanical and nonisothermal crystallization properties of coal gasification fine slag glass bead‐filled polypropylene composites

“…At low filler weight fractions, the tensile strength of the PP/CGFSGB‐A composites is close to the values of other composites, but at high loadings, the tensile strength of the PP/CGFSGB‐A composites is higher. The reason may be that the degree of interfacial adhesion between the CGFSGB‐A particles and the PP matrix is relatively good, and the interface could transfer effectively somewhat tensile load, leading to the tensile strength changing slightly with increasing filler weight fractions . This shows that the interfacial adhesion between the CGFSGB and the matrix increases after surface activation by HCl because the surface of CGFSGB became rough and porous and had a smaller particle size after activation with HCl.…”

“…Compared with that of the CGFSGB, the average particle size of CGFSGB‐A decreased due to the extraction of Ca, Fe, and Al by HCl. The CGFSGB is amorphous, and the energy stored in the system is high, so agglomeration is likely to occur . After the CGFSGB was acid‐dissolved, the energy stored was released, and the system became more stable, so the agglomeration phenomenon was weakened.…”

“…It is generally thought that the tensile strength of the composites depends, to a large extent, on the interfacial adhesion between the inorganic filler and the polymer matrix. Better interfacial adhesion leads to a higher tensile strength of the polymer composites . In this section, the comparison of tensile strength between CGFSGB, CGFSGB‐S, CGFSGB‐A, and CC‐filled PP composites at different filler contents is discussed.…”

“…This shows that the interfacial adhesion between the CGFSGB and the matrix increases after surface activation by HCl because the surface of CGFSGB became rough and porous and had a smaller particle size after activation with HCl. As well known, the tensile strength of the composites depends on many factors, such as the distribution of particle size, geometric shape, and surface properties of the filler particles . In the research, the results show that the geometric shape of particles is the main influencing factor.…”

“…CGFS has been applied in low‐density polyethylene, but the application of CGFSGB has not yet been reported. The CGFSGB has higher surface reaction activity owing to its amorphous phase, which provides more possibility of modification. Acid‐leaching treatment is expected to aid in the potential applications of coal gasification slag, resulting in the partial removal of Fe, Al, and Ca, leading to surface erosion and collapse, and leaving behind a framework structure possessing a larger surface area to produce the porous matter .…”