Stereo block copolymers of G and mlactides
نویسنده
چکیده
Sequential diblock copolymers composed of G and D-lactic acid residues were synthesized through a living ring-opening polymerization of t and D-lactide initiated by aluminium tris(2-propanolate). The composition of the block copolymers was varied by changing the reaction conditions and monomer over initiator ratio and confi ied by 'H NMR analysis, molecular weight determination and optical rotation measurements. Molecular weights ranged from 1,3 to 2,O. lo4 with 1,2 < MJM, c 1.4. Stereocomplex formation in all block copolymers was determined using differential scanning calorimetry showing melting temperatures of about 205 "C.
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