SAPO-18 molecular sieve was synthesized by a dry gel conversion (DGC) and hydrothermal (HT) synthesis method using methyltriethoxysilane as the only Si source (DGC-Me-SAPO-18 and HT-Me-SAPO-18). Their physicochemical and catalytic properties on dimethylether-to-olefin (DTO) reaction were compared with those of conventional SAPO-18 molecular sieves synthesized by a hydrothermal synthesis method (HT-SAPO-18). An NH 3-TPD measurement revealed that the desorption peak position of Brønsted acid of the Me-SAPO-18 samples moved to lower temperature, indicating that Brønsted acidic strength of the Me-SAPO-18 samples was lower than that of the HT-SAPO-18 samples. The DME conversions and yields of light olefins over DGC-Me-SAPO-18 decreased at a slower rate than those of HT-SAPO-18. The decreased acidic strength and flake-like morphology of DGC-Me-SAPO-18 could retard the coke formation, leading to the prolonged catalytic lifetime.

Seamless star polymer synthesis via polymer‐linking reaction was achieved based on highly monomer‐selective living cationic polymerization. First, a vinyl ether was polymerized exclusively from its mixture with a styrenic‐type divinyl compound, and then the ensuing in situ reaction of the divinyl compound with the resulting linear living polymers produced a star polymer with well‐defined structures in very high yield. This is the first example of highly controlled one‐step synthesis of star polymers via the polymer‐linking reaction.

This article demonstrates the biphasic synthesis of “block” copolymers and star‐shaped polymers via monomer‐selective cationic copolymerization in the biphasic system of organic/fluorinated solvents. The first monomer and second monomer were dissolved in hexane (upper phase) and dichloropentafluoropropane (lower phase), respectively. The first monomer was polymerized in the upper phase, while the comonomer still remained unreacted in the lower phase. At the point of almost complete consumption of the first monomer, two phases were stirred vigorously to become a single copolymer with low polydispersity. Monomer‐selective reaction was achieved even from a combination of monomers with similar reactivities. Moreover, an efficient one‐shot formation of star‐shaped polymers was feasible through the copolymerization of monomer and divinyl compound in the biphasic system.

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