Home About us Contact
|
Home About us Contact | ||
|
|
||
Very Good Solubility (very + good_solubility)
Selected AbstractsAn efficient approach to synthesize polysaccharides- graft -poly(p -dioxanone) copolymers as potential drug carriersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2009Fang Lu Abstract Starch and poly(p -dioxanone) (PPDO) are the natural and synthetic biodegradable and biocompatible polymers, respectively. Their copolymers can find extensive applications in biomedical materials. However, it is very difficult to synthesize starch- graft -PPDO copolymers in common organic solvents with very good solubility. In this article, well-defined polysaccharides- graft -poly(p -dioxanone) (SAn -PPDO) copolymers were successfully synthesized via the ring-opening polymerization of p -dioxanone (PDO) with an acetylated starch (SA) initiator and a Sn(Oct)2 catalyst in bulk. The copolymers were characterized via Fourier transform infrared spectroscopy, 1H NMR, gel permeation chromatography, thermogravimetric analysis (TG), differential scanning calorimetry, and wide angle x-ray diffraction. The in vitro degradation results showed that the introduction of SA segments into the backbone chains of the copolymers led to an enhancement of the degradation rate, and the degradation rate of SAn -PPDO increased with the increase of SA wt %. Microspheres with an average volume diameter of 20 ,m, which will have potential applications in controlled release of drugs, were successfully prepared by using these new copolymers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5344,5353, 2009 [source] Synthesis of gradient copolymers with complexing groups by RAFT polymerization and their solubility in supercritical CO2JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2009Tiphaine Ribaut Abstract We report the synthesis of new gradient fluorinated copolymers with complexing groups and soluble in supercritical carbon dioxide (scCO2). Poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -acetoacetoxyethyl methacrylate) (poly(FDA- co -AAEM)) and poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -vinylbenzylphosphonic acid diethylester) (poly(FDA- co -VBPDE)) gradient copolymers were synthesized by reversible addition fragmentation chain transfer polymerization in ,,,,,-trifluorotoluene. Poly(1,1,2,2-tetrahydroperfluorodecyl acrylate- co -vinylbenzylphosphonic diacid) (poly(FDA- co -VBPDA)) gradient copolymer was efficiently obtained by cleavage of the phosphonic ester groups of poly(FDA- co -VBPDE). The cloud points of these gradient copolymers in dense CO2 were measured in a variable volume view cell at temperatures between 25 and 65 °C. The gradient copolymers show very good solubility in compressed CO2 with the decreasing order: poly(FDA- co -AAEM) , poly(FDA- co -VBPDE) > poly(FDA- co -VBPDA). Following a green chemistry strategy, poly(FDA- co -AAEM) gradient copolymer was successfully synthesized in scCO2 with a good control over number-average molecular weight and composition. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5448,5460, 2009 [source] Mononuclear Mixed ,-Ketoester-alkoxide Compound of Titanium as a Promising Precursor for Low-Temperature MOCVD of TiO2 Thin Films,CHEMICAL VAPOR DEPOSITION, Issue 6 2003R. Bhakta A monomeric titanium complex suitable for liquid-injection MOCVD applications is synthesized and its molecular structure is determined by single-crystal X-ray diffraction. [Ti(OiPr)2 -(tbaoac)2] (see Figure), (tbaoac),=,tertiarybutylacetoacetonate), is a volatile alkoxide-(beta)diketonate precursor that has a low melting point and very good solubility in common organic solvents. [source] Synthesis, Photophysics and Morphology of a Conjugated Polymer with Azobenzene Building Block in the BackboneCHINESE JOURNAL OF CHEMISTRY, Issue 7 2010Dezhi Shen Abstract A conjugate polymer poly[p -(phenyleneethylene)-alt-(phenyleneazophenyleneethylene)] (PPEPAPE) containing azobenzene building block in the polymer backbone was synthesized via Sonogashira cross-coupling of 4,4,-diiodoazobenzene and 1,4-diethynyl-2,5-didodecyloxybenzene. All the monomers and the resulting polymer were well characterized. The polymer had a relatively high molecular weight and showed very good solubility (,10 mg/mL) in common organic solvents. The photophysics of this polymer in solution and in film was investigated. The surface morphology of the films was studied by scanning electron microscope (SEM) and the relationship between the morphology and absorbance was discussed. This polymer has good film-forming property, broad absorbance and no emission, which might make it a good candidate for the photovoltaic material in the solar cell. [source] | ||||||||||