Study On Pentaerthritol Tetramine As The Central Molecule Of The New Star-polymers

Star polymer application have attracted interest and attention its performance in the field of polymer materials, because of the increasing demand of biopolymers with tunable properties, including hydrophilicity, degradation rate, biological applications, etc. At present, the polylactic acid(PLA), poly amino acid and copolymer have good biodegradability and biocompatibility properties, are the most commonly used polymer materials by far because they are environmentally friendly, and had been widely used in drug controlled release system, tissue engineering, food packaging, and other fields. However, with the widely used of PLA and poly amino acids, its shortcomings have gradually revealed, such like poor flexibility, slow degradation rate and poor hydrophilicity, limits its application. This paper mainly dissertation includes that obtained star polymer with different functional properties by introducing in different functional groups.A novel star miktoarm PLA-poly(L-glutamic acid) copolymer is synthesized in which the center is composed of pentaerythrityl tetramine grafted with Boc-Lys(Boc)-OH. The protective groups(CBZ and BOC) of Boc-Lys(Boc)-OH are removed, and a functional amino group is used to initiate ring-open polymerization with Lac-OCA and Glu-NCA. A series of star polymer used as drug release carriers were studied. The main research content is as follows:(1) Pentaerythritol as raw materials, conversion of-OH into-NH2, the structure is analyzed by1 H nuclear magnetic resonance(1H NMR).(2) star polymer obtained by pentaerythrityl tetramine as the center, then grafted with Boc-Lys(Boc)-OH, the amine groups is exposed by removing a protective group(CBZ) and protective group(BOC).ring opening polymerization of Lac-OCA and Glu-NCA under amine as initiator, the characterize of star polymer are analyzed by nuclear magnetic resonance(NMR) and infrared spectroscopy(IR). After the star polymer synthesis of benzyl removal, the synthesized polymers were used as drug delivery carriers to wrapped antimicrobial peptide prepared polymer microspheres.(3) a series of methyl propionate was prepared at the end of this paper, methyl acrylate are obtained by thionyl chloride and methyl acrylic acid as raw materials and reaction of alcohol, the methodology provided a mild and simple.