843-55-0Relevant articles and documents
Losev et al.
, p. 589 (1963)
Method for preparing high-purity kerley Bette
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Paragraph 0033; 0034, (2016/10/07)
The invention relates to a preparation method of high-purity clinofibrate, the field of preparation of pharmaceutical compounds. The preparation method comprises the following steps: reacting cyclohexanone and phenol in concentrated hydrochloric acid and glacial acetic acid in a volume ratio of 3:1-7:1 to obtain an intermediate I crude product, decolorizing with a single solvent, and cooling to crystallize to obtain an intermediate I; reacting 2-methylbutyric acid with liquid bromine in phosphorus trichloride, reacting with anhydrous alcohol, extracting, and carrying out vacuum distillation to obtain an intermediate II; reacting the intermediate I and the intermediate II under solventless conditions to obtain an intermediate III; and hydrolyzing the intermediate III and sodium hydroxide, extracting, crystallizing to obtain a clinofibrate crude product; and recrystallizing with an anhydrous solvent to obtain the clinofibrate. The material proportion is adjusted to shorten the production operation period; the invention has the advantages of low energy consumption and low solvent consumption; and the obtained product has the advantages of uniform crystal grains, high purity and low cost.
Design of lamellar structured POSS/BPZ polybenzoxazine nanocomposites as a novel class of ultra low-k dielectric materials
Sasi Kumar,Ariraman,Alagar
, p. 19127 - 19136 (2014/05/20)
A novel class of lamellar structured polyhedral oligomeric silsesquioxane/bisphenol Z (POSS/BPZ) polybenzoxazine (PBz) nanocomposites was successfully designed by a facile one-step copolymerization technique. The chemical structures of the monomer and resulting polymer were characterized by Fourier transform infrared (FTIR) spectroscopy, 1H, 13C, DEPT-135, 29Si NMR (nuclear magnetic resonance) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The desired cross-linked lamellae structural arrangement of POSS/BPZ polybenzoxazine (PBz) nanocomposites was confirmed by transmission electron microscopy (TEM). The BPZ-PBz and POSS-PBz layers were self-assembled by intermolecular hydrogen bonding in such a way as to form the lamellar structure during ring opening polymerization. An advantage of this lamellar structure is that 30% POSS/BPZ polybenzoxazine composite exhibits an ultra low-k value of 1.7 at 1 MHz as well as high thermal stability. the Partner Organisations 2014.