Aluminum Complex Initiated Copolymerization of Lactones and DL-Lactide to Form Crystalline Gradient Block Copolymers Containing Stereoblock Lactyl Chains

作者：Matsubara Kouki^*; Eda Kiyoka; Ikutake Yuki; Dan Misato; Tanizaki Nao; Koga Yuji; Yasuniwa Munehisa

来源：Journal of Polymer Science Part A: Polymer Chemistry , 2016, 54(16): 2536-2544.

DOI：10.1002/pola.28131

• copolymerization
• gradient copolymer
• polyesters
• ring-opening polymerization
• stereoblock copolymer

The homopolymerization reactions of several lactones, as well as the copolymerization reactions of DL-lactide with these lactones were investigated using tridentate Schiff base aluminum complexes as the initiators. epsilon-Caprolactone and d-valerolactone polymerized efficiently at room temperature to afford polyesters, whereas b-butyrolactone only gave the corresponding oligomer. The copolymerization reactions of DLlactide with caprolactone and valerolactone yielded gradient block copolymers where the lactyl blocks formed crystalline stereoblocks as a consequence of the stereoselective polymerization of DL-lactide in the presence of the aluminum com-plexes. These polymerization processes were highly controlled in nature, and block copolymerization where caprolactone copolymerized using poly(DL-lactide)-Al complex proceeded. The obtained gradient copolymer containing stereoblock lactyl blocks and caproyl blocks were analyzed using WAXD analysis to uncover existence of the crystalline stereoblock lactyl blocks in the copolymer.

• 出版日期2016-8-15