Effects of organoclay on the compatibility and interfacial phenomena of PE/EVA blends with UCST phase behavior

Abstract

The compatibilization effects of organically modified nanoclay on the miscibility window, phase separation kinetics, biphasic morphology, interfacial tension, and final properties of polyethylene/ethylene vinyl acetate copolymer blends exhibiting UCST behavior have been investigated. Regardless of blend composition, intercalated nanoclay decreases the phase transition temperatures to lower values and changes the symmetry of phase diagram. The miscibility of PE and EVA phases in the amorphous regions of nanocomposites noticeably enhances and finer biphasic morphology is obtained by the incorporation of organoclay. The pinning influence of the nanofiller on polymer chain diffusion causes much slower phase separation kinetics for the nanocomposites. Similar to conventional compatibilizers such as block copolymers, the interfacial activity of nanoclay leads to a sharp decline in the interfacial tension of PE/EVA up to 2‐orders of magnitude. Moreover, the results show that imposing restrictions on the phase separation phenomenon increases the impact strength of the virgin blend and related nanocomposite. However, this improvement has been much more noticeable in the presence of nanoparticles, which is due to the simultaneous roles of organoclay as an effective compatibilizer and reinforcement. POLYM. COMPOS., 35:2329–2342, 2014. © 2014 Society of Plastics Engineers

Influence of nitrogen plasma treatment on the wettability of polyetheretherketone and deposited chitosan layers

“…The equilibrium contact angle [21][22][23][24][25][26][27][28][29][30] was calculated for all tested surfaces and its value is between the advancing and receding contact angles, however, it is not their average. The water contact angles for the surfaces obtained in this way were 71.2 ± 2.8° and 69.9 ± 2.2°, respectively.…”

“…It is almost impossible to satisfy these requirements under laboratory conditions. Thus, Tadmor [21][22][23][24][25][26][27][28][29][30] proposed another equation for calculation of the equilibrium contact angle.…”

“…Some theoretical approaches used for energy determination should be mentioned here, for example, the acid-base approach proposed by van Oss et al, [31][32][33] Newmann equation of state, [34] Owens and Wendt approach, [35] hysteresis approach proposed by Chibowski [36][37][38] , and others. [39][40][41] In this paper, the value of apparent surface energy from the LWAB, [31][32][33] Owens and Wendt [35] as well as CAH [36][37][38] approaches will be compared and the Tadmor [21][22][23][24][25][26][27][28][29][30] equilibrium contact angle will be used for calculations when these approaches are applied.…”

Controlling arbitrary humidity without convection

“…Future studies that incorporate the proposed tool with such systems will improve the accuracy of experimental findings in these fields. Examples for such fields include processes such as Marangoni flows where controlling the vapors of the volatile component is essential [50], for system that require careful drying as in the case of phospholipid films [51], or for systems that consider solid liquid interactions in which the humidity needs to be controlled as in concrete-water interactions [52] or interactions of water with hydrophobic microstructures [53], or any other system that consider small volumes of volatile components [33,[54][55][56][57][58][59][60][61][62][63]. …”

Wettability of modified silica layers deposited on glass support activated by plasma

“…Moreover, the equilibrium contact angle proposed by Tadmor was used for apparent surface free energy evaluation [30][31][32][33][34][35][36]:…”