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11.
An efficient and practical method for the synthesis of sterically hindered aliphatic/aromatic 1,3‐diketones via coupling of ketones with esters using potassium tert‐butoxide is described. The protocol requires milder operating conditions, and the products are obained in good to excellent yields. 相似文献
12.
A method based on the intrinsic viscosities of transfer has been used to predict miscibility of polymer blends. This method has been applied to study the change in the phase behaviour of a microphase separated polyester polyurethane (PSPU) on blending with polyvinyl chloride (PVC), polyvinyl acetate (PVAc) and a vinyl chloride-vinyl acetate copolymer (VCVAc). The PVC/PSPU blends are found to exhibit complete miscibility over the entire composition range. PVAc/PSPU blends show immiscibility while VCVAc/PSPU blends show partial miscibility. Thermal analysis and scanning electron microscopic studies of the blend films have confirmed the results evaluated on the basis of the viscosity method. 相似文献