Water is eco‐friendly and safe; thus, it used as a blowing agent in the fabrication of water‐blown polyurethane (PU) foam. However, water‐blown PU foam may experience dimensional instability due to shrinkage of the cells inside the foam. In order to reduce cell shrinkage due to the loss of CO2 gas, vacuum formation is prevented in the closed‐cell foam and the maximum reaction temperature must be raised to increase the degree of curing of the PU foam. In this study, two flame retardants, aluminum trihydrate (ATH) and magnesium dihydrate (MDH), were selected as additives to partially open the cells and increase the maximum reaction temperature. ATH and MDH were both effective for increasing the maximum foam reaction temperature and decreasing dimensional change. Notably, PU foams with 7.5 wt% ATH were the most dimensionally stable at both room temperature and high temperature. Moreover, the compressive strength and flexural strength of such foams were also improved compared to those of the foams without any additive.

Using Korean data, we investigate information asymmetry among investors before analysts change their stock recommendations. By comparing trading activities between individuals, institutions, and foreign investors, we find that there is information asymmetry before analysts change their recommendations. Institutional investors buy/sell the stock before recommendation upgrades/downgrades, but individuals and foreign investors do not anticipate the upcoming news. We also document that the trade imbalance of institutional investors are associated with stock returns upon the announcements of recommendation changes. This result indicates that institutions take advantage of their superior information around the recommendation changes.

Tetrasubstituted thieno[3,2‐b]pyridin‐5(4H)‐one derivatives were selected as a highly functionalized heterocyclic scaffold for a multisite‐specific tagging process utilizing a previously devised fluorous fluorescent tag system. A suitable synthetic method was established for the 7‐alkoxy‐2,4,6‐trisubstituted‐thieno[3,2‐b]pyridin‐5(4H)‐one derivatives, and incorporating t‐butoxycarbonyl‐functionalized building blocks into the reaction sequence produced precursors that could be used in the tagging process. Fluorous solid‐phase extraction facilitated the purification of the tagged target compounds after a series of reactions, including t‐Bu deprotection/N‐hydroxysuccinimidyl ester formation/amidation.

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