Effect of a filler on the rheological and mechanical properties of the liquid-crystalline polyester-poly(methyl methacrylate) blends

Abstract

ABSTRACT:The rheological and mechanical properties of the blends of liquid-crystalline polyester (LCP) and poly(methyl methacrylate) (PMMA) filled with aluminum borate whiskers have been studied. It was established the combined action of reinforcing LCP and filler onto the property of PMMA matrix leads to marked reinforcing of PMMA. At 10% of filler and 30% of LCP, the tensile strength of PMMA increases by 30% and elasticity modulus by 110%, the processability being no worse. The viscosity of the blend PMMA ϩ 30% LCP ϩ 10% filler practically is the same as the PMMA melt viscosity at 220°C. With increasing concentration of LCP up to 30%, the filler effect in binary matrix becomes more essential. The possible reason is the preferential adsorption of LCP at the filler interface (surface segregation) and additional ordering of LCP near the surface, possible, due to additional stretching of nematic phase in the convergent flow zone.

Hybrid effects of zirconia nanoparticles with aluminum borate whiskers on mechanical properties of denture base resin PMMA

“…Whiskers are a highly pure and acicular material with a single crystal structure fabricated under well controlled conditions. Their large length-diameter ratio effectively prevents the matrix from crack development, while their highly ordered arrangement of atoms results in low brittleness, thus enhancing the mechanical properties 17) . Among the whisker reinforcement materials, aluminum borate (Al 18B4O33) whiskers offer superior mechanical properties at a low cost.…”

Processability and mechanical performance of hybrid composites based on poly(ether sulfone) modified with a glass fiber–reinforced liquid crystalline polymer

“…Figure 6 shows the tensile strength of the composites as a function of gLCP content: it decreased upon gLCP addition. This behavior is not unusual in hybrid composites because the tensile strength has been seen to increase, [27][28][29] decrease, 32,33 or remain constant 24 with the LCP content. Considering the reasons for this tensile strength behavior, the decrease on addition of 10% gLCP must be partially influenced by the fast breaking, which should overcome the increase in the modulus.…”

“…4,22 Fillers have also been used to reinforce thermoplastic/LCP blends. In most studies, the inorganic reinforcement was added as a third component, [23][24][25][26][27][28][29][30][31][32] but fiber-reinforced matrices, such as glass fiber-reinforced poly(ether imide) (PEI) 33 or PES, 34 have also been used. There are many studies of filled LCPs [2][3][4][5][6]22,[35][36][37] and filled thermoplastic/LCP blends [23][24][25][26][27][28][29][30][31][32][33] ; however, to our knowledge there is no study of thermoplastic/ filled LCP composites.…”

Rheological hybrid effect in nylon 6/liquid crystalline polymer blends caused by added glass beads

“…Since this original work, several hybrid composites containing LCP component have been reported. In these composite systems, fillers have been used with different shapes and sizes, such as 'whiskers' [3][4][5], glass fiber [1,2,[6][7][8][9][10][11][12][13], carbon fiber [2], silica nanoparticle [14][15][16][17][18] and ferromagnetic particle [19]. Most reports on these hybrid blends are focused on the mechanical and rheological properties.…”

“…Shumsky et al [5] studied the effect of aluminum borate whiskers on the rheological and mechanical properties of liquid crystalline polyester-poly (methyl methacrylate) (PMMA) blends, and found the blend capillary or converging entrance region. At the entrance of the instantaneously formed capillary, LCP droplets underwent elongational flow, so that they deformed into fibrils with large aspect ratios.…”