文献类型：期刊文献

英文题名：Latent Catalyst-Containing Naphthoxazine: Synthesis and Effects on Ring-Opening Polymerization

作者：Zhang, Wenfei[1,2];Froimowicz, Pablo[1,3];Arza, Carlos R.[1];Ohashi, Seishi[1];Xin, Zhong[2];Ishida, Hatsuo[1]

机构：[1]Case Western Reserve Univ, Dept Macromol Sci & Engn, Cleveland, OH 44106 USA;[2]East China Univ Sci & Technol, Shanghai Key Lab Multiphase Mat Chem Engn, State Key Lab Chem Engn, Sch Chem Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China;[3]Univ Buenos Aires, Design & Chem Macromol Grp, ITPN, UBA CONICET,Sch Engn, Las Heras 2214 CP 1127AAR, Buenos Aires, DF, Argentina

年份：2016

卷号：49

期号：19

起止页码：7129

外文期刊名：MACROMOLECULES

收录：;EI(收录号：20164202925457);WOS:【SCI-EXPANDED(收录号:WOS:000385335800002)】；

基金：W. Zhang gratefully acknowledges the financial support of Chinese Scholarship Council (CSC) Program.

语种：英文

外文关键词：Nuclear magnetic resonance spectroscopy - Thermogravimetric analysis - Catalysis - Catalysts - Differential scanning calorimetry - Hydrogen bonds - Nuclear magnetic resonance - Ring opening polymerization - Synthesis (chemical)

摘要：A naphthoxazine containing a latent catalyst based on -OH as part of its monomer structure has been synthesized through a simple one-pot reaction at room temperature. The chemical structure of this naphthoxazine monomer has been confirmed by H-1 NMR, C-13 NMR, and FT-IR and its purity by elemental analysis. Differential scanning calorimetry (DSC) and in situ FT-IR have been used to investigate the active and inactive conditions for the latent catalysis. DSC and thermogravimetric analysis (TGA) studies indicate that this naphthoxazine polymerizes quickly before the monomer evaporation, as is often the case for conventional naphthoxazines, minimizing the monomer loss during polymerization. The intramolecular interactions between the -OH group and oxazine ring and pyrrolidine ring of the monomer have been investigated in detail by using the homonuclear two-dimensional (2D) NMR technique H-1-H-1 nuclear Overhauser effect spectroscopy (NOESY). The -OH interacts with the N in the pyrrolidine ring and oxazine ring through stable intramolecular hydrogen bonds instead of presenting free -OH at room temperature, leading to the enhanced shelf life of the monomer. The free phenolic -OH initiates and catalyzes the polymerization once the hydrogen-bonded interactions are weakened or disrupted upon increasing temperature, showing a latent catalytic effect.