| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 고분자 합성 |
| 제목 | Vinyl polymerization of norbornene using Nickel (II) α-diimine catalyst: Effect of alkyl substituents |
| 초록 | Norbornenes are known to be polymerized by ring opening metathesis, cationic or vinylic pathway. Owing to their unique physical properties such as high glass transition temperature, good heat resistivity, high optical transparency, and excellent dielectric properties polynorbornenes via vinyl polymerization route have gained immense attraction recently. In the present study we synthesized a series of Ni (II) α-diimine catalysts (Fig. 1) bearing alkyl substituents at different positions of the aryl ring. These catalysts were analyzed for its norbornene polymerization activity and effects of different alkyl substituents and their positioning were ascertained. Catalyst 2,5 Me2 was found to be the most active where as 2,3 substituted the least and this is due to less crowding offered the active species thereby promoting the rate of monomer insertion. The study was further extended to find effect of polymerization temperature, monomer concentration and type of cocatalyst on activity and properties of polymers formed. Thermal analyses showed that polymers were stable up to 470oC and have glass transition around 190oC. Determination of optical transparency and dielectric properties of the polymer were also undertaken. Fig 1. Catalysts used for the present study |
| 저자 | 비누, 하창식, 김일 |
| 소속 | 부산대 |
| 키워드 | late transition metals; polynorbornene; ligand structure variation |
