title: Synthesis and properties of optically active nanostructured polymers bearing amino acid moieties by direct polycondensation of 4,4'-thiobis(2-tert-butyl-5-methylphenol) with chiral diacids.
abstract: Four derivatives of N-trimellitylimido-L-amino acid (4a-4d) were prepared by the reaction of trimellitic anhydride (1) with the L-amino acids (2a-2d) in acetic acid as diacid monomers and were used with the aim to obtain a new family of amino acid based poly(ester-imide)s (PEI)s. The polymerization was performed by direct polycondensation of chiral diacids (4a-4d) with 4,4'-thiobis(2-tert-butyl-5-methylphenol) (5) in the presence of tosyl chloride (TsCl), pyridine and N,N-dimethyl formamide (DMF). Step-growth polymerization was carried out by varying the time of heating and the molar ratio of TsCl/diacid and the optimum conditions were achieved. The synthesized polymers were characterized by means of specific rotation experiments, FT-IR, 1H-NMR, X-ray diffraction techniques and elemental analysis. The surface morphology of the obtained polymers was studied by field emission scanning electron microscopy. The result showed nanostructure morphology of the resulting polymers. The obtained PEIs were soluble in polar aprotic solvents such as DMF, N,N-dimethyl acetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and protic solvents such as sulfuric acid. Thermal stability and the weight-loss behavior of the PEIs were studied by thermal gravimetric analysis (TGA) techniques. TGA showed that the 10% weight loss temperature in a nitrogen atmosphere was more than 402°C, therefore they had useful levels of thermal stability associated with excellent solubility.
authors.affiliation: Department of Chemistry, Organic Polymer Chemistry Research Laboratory, Isfahan University of Technology, 84156-83111, Isfahan, Islamic Republic of Iran, mallak@cc.iut.ac.ir.
authors.forename: Shadpour
authors.initials: S
authors.lastname: Mallakpour
authors.forename: Samaneh
authors.initials: S
authors.lastname: Soltanian
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D004126:Dimethylformamide; D005559:Formamides / Q000737:chemistry; D007094:Imides / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010636:Phenols / Q000737:chemistry*; D010796:Phthalic Anhydrides / Q000737:chemistry; D011091:Polyesters / Q000138:chemical synthesis*; D058105:Polymerization; D011725:Pyridines / Q000737:chemistry; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014105:Tosyl Compounds / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000596:Amino Acids; D005559:Formamides; D007094:Imides; D010636:Phenols; D010796:Phthalic Anhydrides; D011091:Polyesters; D011725:Pyridines; D014105:Tosyl Compounds; C025506:4-toluenesulfonyl chloride; C015559:trimellitic anhydride; D004126:Dimethylformamide; C023666:pyridine