Inclusion complexes (ICs) between alpha-cyclodextrin (alpha-CD) and three kinds of biodegradable aliphatic polyesters with different sequence lengths of the monomeric repeating units poly(3-hydroxypropionate) [P(3HP)], poly(4-hydroxybutyrate) [P(4HB)] and poly(epsilon-caprolactone)(PCL) were prepared by mixing a solution of alpha-CD with that of the polymer, followed by stirring. The ICs were obtained as insoluble precipitates and characterized by FT-IR, WAXD and DSC. All measurements showed that the polymer chains of all three kinds of polyester were included into the alpha-CD cavity and formed ICs with different stoichiometries. WAXD patterns and thermal analysis indicated that these ICs possessed a channel structure and the crystallization of the polyester chains was suppressed upon inclusion into the alpha-CD cavity.

In this study, the use of cotton fiber (CF) as a filler in poly(butylene succinate) (PBS) and the effect of silane treatment on the mechanical properties, thermal stability, and biodegradability of PBS/CF composites are investigated. The results showed that the tensile strength of PBS was improved (15%–78%) with the incorporation of CF (10–40 wt%) and was further increased (25%–118%) when CF was treated with a silane coupling agent. Scanning electron microscopy (SEM) observation of the fracture surfaces of PBS/CF composites showed that there was slight improvement in fiber-matrix compatibility. Thermogravimetric (TG) analysis showed that the thermal stability of the composites was lower than that of neat PBS and decreased with increasing filler loading. The biobased carbon content of the composites increased with increasing CF content. The incorporation of CF (with and without silane treatment) in PBS significantly increased the biodegradation rate of the composites

Dibutyl 2,5-furandicarboxylate (2) and dibutyl 2,3-furandicarboxylate (3) were synthesized using one step from galactaric acid and 1-butanol. Sulfuric acid, p-toluenesulfonic acid, and heteropolyacids were good catalysts for the reaction. The reaction time was dependent on the amount of the catalyst, but the final yields of the main product, 2 remained unchanged.

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Polymer-supported selenocyanates were readily prepared from substituted-polystyrene resins such as Merrifield resin and aminomethyl-polystyrene resin. Employing these polymer-supported selenocyanates, the corresponding oxyselenenylation-deselenenylation reactions proceeded in the solid-phase.Solid-phase organic synthesis is a powerful and rapid method for the preparation of large numbers of structurally distinct molecules. 1 In the case of this technique, the purification of organic molecules has been greatly simplified through the use of polymer-resins.The use of organoselenium reagents in organic synthesis is now commonly accepted as a powerful tool for introducing new functional groups into organic substrates under extremely mild reaction condition. 2 Among them, selenocyanate is a useful seleno-introducing reagent that is employed as both an electrophilic and nucleophilic reagent. 3 Very recently, Nicolaou et al. have reported the preparation of polymer-supported selenenyl bromide from polystyrene resin and its application to organic synthesis. 4 Herein, we wish to report the very simple preparation of polymer-supported selenocyanates 5 from substituted-polystyrene resins such as the readily available Merrifield resin and aminomethyl-polystyrene resin, and their application as reagents to the oxyselenenylationdeselenenylation reaction in the solid-phase. A remarkable advantage of these polymer-supported selenocyanates is their easy handling and odorless nature, as compared with non-supported selenocyanates, whose toxicity and strong odor is often problematic in the laboratory.Polymer-supported selenocyanates were prepared according to Scheme 1. Chloromethyl-polystyrene resin 1 (Merrifield resin, 4.3 mmol/g, crosslinked with 2 % divinylbenzene) was treated with potassium selenocyanate in N,N-dimethylformamide (DMF) at room temperature for overnight. Formation of polymer-supported selenocyanate 2 was indicated by IR spectra showing a strong stretching vibration of the cyano group at 2149 cm -1 . Elemental analysis of selenium showed that 2 was obtained in nearly quantitative yield. 6 Similarly, Wang bromo resin 3 (1.05 mmol/g, crosslinked with 1 % divinylbenzene), which possessed a phenoxymethyl linker, also afforded the corresponding polymer-supported selenocyanate 4 in nearly quantitative yield. 7In application to solid-phase synthesis, we have examined an electrophilic oxyselenenylation reaction, 2d which proceeds exclusively by mechanism of trans-addition. First, through the addition of bromine to 2 in dichloromethane to produce the corresponding selenenylbromide, 8 elemental selenium was deposited via the decomposition of 2, contrary to our expectation. Then, stirring 2 and (E)-4-phenyl-3-butenoic acid in the presence of copper chloride (II) in toluene at 80 °C, 9 the corresponding intramolecular oxyselenenylation (namely, selenolactonization) proceeded in the solid-phase to produce polymer-supported selenolactone 5(n=0) (Scheme 1), indicated by a strong carbonyl stretching vibration at 1776 cm -1 in the I...