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Novel crosslinked thin polymer networks based on vegetable oil hydroxy fatty acids (HFAs) were prepared by UV photopolymerization and their mechanical properties were evaluated. Two raw materials, castor oil and 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) were used as sources of mono-and di-HFAs, respectively. Poly (ethylene glycol) (PEG) diacrylate and poly(e-caprolactone) diacrylate were synthesized and used as crosslinking agents to form crosslinked polymer networks by UV-initiated free-radical polymerization with acrylated castor oil or acrylated DOD. The synthesis of acrylate derivatives was confirmed using FT-IR and 1 H-NMR spectroscopic techniques. The composition of the reaction mixture and the type/length of crosslinking agent were changed to obtain crosslinked polymer networks with various mechanical properties. For polymers prepared from high molecular weight (20,000) PEG, a 58-60% of the initial weights decreased in 35 days in phosphate buffer solution (pH 7.2) containing lipase enzyme. These potentially biodegradable polymers based on vegetable oil HFAs can be used as eco-friendly materials for various applications to replace the existing petroleum-based polymers currently used.

PurposeToday, online malicious comments are serious issues. They can cause psychological distress and suicide of victims. Although prior studies have focused on the role of anonymity as a major factor in making these comments, results of these studies have been inconsistent. On the other hand, the need for attention from others can provide an alternative explanation for such malicious comments. However, this perspective has been rarely studied. Therefore, the objective of this study was to investigate effects of anonymity and need for attention on posting malicious comments online and compare these two factors, resolving dark sides of online interaction.Design/methodology/approachThis study obtained 327 questionnaires of Facebook users through a survey and analyzed the research model using partial least squares (PLS) regression.FindingsResults of this study revealed that the need for attention affected malicious comments through partial mediation of neutralization. On the other hand, anonymity did not significantly affect malicious comments.Research limitations/implicationsThis study has the following academic implications. First, we empirically examined the critical influence of need for attention on making malicious comments online based on the impression management theory. Second, this study revealed that the influence of need for attention on making malicious comments was partially mediated by neutralization. Third, this study may offer an explanation for contradicting findings on the role of anonymity in the phenomenon of posting malicious comments online.Practical implicationsPractical implications of this study are as follows. First, SNS platforms can limit activities of persons who post malicious comments frequently. Second, this study suggests that a notice is needed to inform the seriousness and harmful consequences of malicious comments. Third, Facebook practitioners should be aware that low anonymity may not reduce malicious comments.Originality/valueThis study quantitatively examined the effect of need for attention on malicious comments based on the impression management theory. It provides a fact that individuals who want to attract attention from others would write malicious comments through neutralization.

The rapid development of electric vehicles has generated a recent demand for high energy density lithium-ion batteries (LIBs). One simple, effective way to enhance energy density of LIBs is to increase the thickness of electrodes. However, the conventional wet process used to fabricate thick electrodes involves the evaporation of large amounts of organic solvents, which causes an inhomogeneous distribution of conductive additives and binders. This weakens the mechanical and electrochemical network between active materials, resulting in poor electrochemical performance and structural degradation. Herein, we introduce a new strategy to produce homogeneous thick electrodes by using a dry, solvent-free process. Instead of using a conventional PVDF (polyvinylidene fluoride) binder, we employed a phenoxy resin as the binder in dry process for the first time. This thermoplastic binder exhibits better ductile properties than PVDF in the way that it generates a uniform network structure that connects the active materials during the hot press process. This enables the production electrochemically stable electrodes without using organic solvents, which record capacity retention rates of 73.5% over 50 cycles at a 40 mg/cm2 of thick electrodes. By contrast, thick electrodes produced with a PVDF binder via wet processing only have a capacity retention rate of 21.8% due to rapid structural degradation.