Effect of polyethylene glycol on the performance of ultrahigh‐molecular‐weight polyethylene membranes

Abstract

Porous, flat membranes of ultrahigh-molecular-weight polyethylene (UHMWPE) were prepared by thermally induced phase separation, with mineral oil as a diluent and poly(ethylene glycol) with a weight-average molecular weight of 20,000 (PEG20000) as an additive. Through the control of the rheological behavior, crystallite size, and pore structure, the influential factors, including the diluent, poly(ethylene glycol) (PEG) content, and cooling rate, were investigated. The results suggested that PEG could decrease the viscosity of UHMWPE/diluent apparently. The crystal density decreased when mineral oil was added, which made the melting point and crystallinity of UHMWPE lower. The crystallization rate and crystallinity also increased with the addition of PEG. However, the addition of excess PEG restrained crystal growth. PEG20000 in membranes could be extracted absolutely through the soaking of the membranes with fresh water for 7 days. With increasing PEG content, both porosity and pure water flux first increased and then decreased, reaching a maximum at a PEG mass fraction of 10%. The cooling rate had a direct effect the crystal structure. A slow cooling rate was good for crystal growth and diluent integration. Therefore, the pure water flux increased along with the temperature of the cooling medium, whereas porosity first increased and then decreased, reaching a maximum at 40 C. V V C 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: [720][721][722][723][724][725][726][727][728] 2010

Fabrication of light‐weight ultrahigh molecular weight polyethylene films with hybrid porous structure and the thermal insulation properties

“…The crystal structure of UHMWPE after extracting LP was characterized by XRD. As shown in Figure 3c, diffraction peaks around 21.6° and 23.9° were observed in all samples, corresponding to the orthorhombic (1 1 0) and (2 0 0) reflections of UHMWPE 28,29 . The crystallinities of UHMWPE porous films were still significantly higher than that of U 100 , indicating that the crystalline structure of UHMWPE was preserved after LP extraction.…”

“…As shown in Figure 3c, diffraction peaks around 21.6 and 23.9 were observed in all samples, corresponding to the orthorhombic (1 1 0) and (2 0 0) reflections of UHMWPE. 28,29 The crystallinities of UHMWPE porous films were still significantly higher than that of U 100 , indicating that the crystalline structure of UHMWPE was preserved after LP extraction. The crystalline sizes of (1 1 0) and (2 0 0) diffraction planes of the samples after LP extraction increased firstly, and then decreased (Figure 3c).…”

Multifunctional Polydopamine Particles as a Thermal Stability Modifier to Prepare Antifouling Melt Blend Composite Membranes

“…Bulk hybridization modification has attracted increasing attention in the construction of an antifouling separation membrane . For example, some hydrophilic polymers, inorganic nanoparticles, and carbon nanotube materials are added as common modifiers to the separation membrane for antifouling modification to improve the overall hydrophilic and antifouling capacity of the separation membrane. ,− Polydopamine (PDA) particles (PDAPs) have been reported as a filler for constructing polymer composites − because of their excellent properties (such as simplicity, self-polymerization, biocompatibility, and antioxidant properties). For example, Liang et al reported immobilized PDA/silver composite nanospheres on an oxidized sodium alginate sponge surface to fabricate antimicrobial sponges; Xiong et al prepared PDAP/poly­(vinylalcohol) biocomposites using different diameters of PDAPs as a filler; and Wang et al used PDA interfacial cross-linking on a porous supporting layer to fabricate thin-film nanocomposite membranes .…”

The effect of binary diluents on the performance of ultrahigh molecular weight polyethylene/SiO2 hybrid hollow fiber membrane

“…Porous UHMWPE membranes could be prepared by TIPS 5–7. In our previous study, the UHMWPE membrane8 and UHMWPE/SiO 2 hybrid membranes9, 10 with better permeability were prepared by TIPS. The main aim of our previous work was to improve membrane permeability through building the multi‐pore‐structure.…”