离子液体作用下CO与苯乙烯的交替共聚反应

Alternating Copolymerization of Carbon Monoxide and Styrene in Ionic Liquids

在室温离子液体1-丁基-3-甲基咪唑四氟硼酸盐的作用下,利用2,2′-联吡啶、氟硼酸和乙酸钯组成复配催化体系催化一氧化碳和苯乙烯共聚,合成了聚(1-氧代-2-苯基丙撑).利用元素分析、示差扫描量热、热质量分析及红外光谱等方法对共聚产物进行了表征.同时,考察了钯复配催化剂在离子液体中对一氧化碳和苯乙烯交替共聚的重复性,使用4次后钯复配催化剂仍有催化活性.通过对比发现在聚合过程中钯复配催化剂的催化效果明显优于加入2,2′-联吡啶和乙酸钯二者混合物的催化效果.分析了离子液体的用量对催化活性的影响,在最优条件下钯复配催化剂对一氧化碳和苯乙烯交替共聚的催化活性可达3.49×103g/(mol.h).

Poly （1-oxo-2-phenyhrimethylene） was synthesized by copolymerization of carbon monoxide and styrene in the presence of the bis-chelated palladium （Ⅱ） complexes presynthesized from palladium acetate, 2, 2＇-bipyridyl, and fluoroboric acid in ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate at room tempe- rature. The copolymer was characterized by elemental analysis, differential scanning calorimetry, thermogravimetry, and Fourier transform infrared spectroscopy to measune the recyclability of bis-chelated palladium （ Ⅱ ） composite catalyst in ionic liquids. The results show that catalytic activity of composite catalyst ionic liquids contained still exists after 4 successive recycles. It also has been shown that the catalytic activity of palladium （ Ⅱ ） composite catalyst is prior to the catalytic activity of the catalyst formed in situ in ionic liquids. The ionic liquids volume also influences the catalytic activity. Under the optimum conditions, the catalytic activity of the his-chelated palladium （ Ⅱ ） composite catalyst reaches 3.49 × 10^3 g/（ mol·h） for the copolymerization of carbon monoxide and styrene.