Block copolymerization of ethylene oxide and acrylonitrile and the influence of block length of polyacrylonitrile on the thermal behavior and morphology of block copolymer

✍ Scribed by Junlian Huang; Xiaoyu Huang; Wenbing Hu; Wenkui Lou

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 572 KB
• Volume: 34
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199605)34:7<1317::aid-pola19>3.0.co;2-c

✦ Synopsis

A bifunctional initiator with the characteristics of anionic and charge transfer polymerization using p-aminophenol as parent compound is useful for synthesis of block copolymers. A block copolymer of ethylene oxide and acrylonitrile (PEO-b-PAN) is prepared by this method. In the first step, p-aminophenol potassium with protected amine group initiated polymerization of ethylene oxide (EO) to yield polyethylene oxide (PEO) with Schiffs base end groups. The charge transfer complexes (CTC) consisted of the PEO prepolymers with aniline group, which is formed by acidolysis of Schiffs base, and benzophenone (BP) initiated the polymerization of acrylonitrile under UV irradiation. Successful blocking has been confirmed by a strong change in the molecular weight of the prepolymer PEO and the block copolymer as well as IR, DSC, and NMR. The block copolymerization are strongly dependent on the polarity of the solvents. The effect of length of PAN block on glass transition temperature of PAN and the crystallinity of PEO block were discussed.