作　　者： ; ; ;

机构地区： 中山大学化学与化学工程学院

出　　处： 《高等学校化学学报》 2010年第6期1257-1262,共6页

摘　　要： 2-氨基吡啶镍配合物[(2-PyCH2NAr)NiBr,Ar=2,6-二甲基苯基(a),2,6-二异丙基苯基(b),2,6-二氟苯基(c)]在助催化剂甲基铝氧烷(MAO)作用下能高活性催化β-蒎烯与降冰片烯共聚合,得到分子量分布较宽(PDI≈3.7～5.5)的共聚产物.在相同条件下,配体含F取代的配合物c对共聚合的催化活性最高.对共聚产物用CHCl3和四氢呋喃(THF)萃取分级,得到2个分子量分布较窄(PDI≈2.0)且组成差异较大的级分,其中仅溶于CHCl3而不溶于THF的级分的分子量较高,具有高降冰片烯含量(xN>90%);而另一个溶于THF的级分的分子量较低,具有较高的β-蒎烯含量.结果表明,共聚合体系中存在2种不同催化性质的活性中心.TGA分析显示,共聚物有2个热分解温度,随着降冰片烯含量的增加,低温处的失重量逐渐减少. In the presence of methylaluminoxane（MAO）,2-aminopyridine Ni（Ⅱ） complexes [（2-PyCH2NAr）NiBr,Ar=2,6-dimethylphenyl（a）,2,6-diisopropylphenyl（b）,2,6-difluorophenyl（c）] presented highly catalytic activity for the copolymerizations of β-pinene and norbornene and afforded the copolymers with broad molecular weight distribution（PDI≈3.75.5）.Complex c exhibited highest catalytic activity for the copolymerization under same conditions.After being extracted by CHCl3 and THF,the crude product could be divided into two fractions with narrow molecular weight distribution（PDI≈2.0）,CHCl3-soluble but THF-insoluble fraction and THF-soluble fraction.The former contains high norbornene content（xN90%） with higher molecular weight and the latter contains high β-pinene content with lower molecular weight,indicating that there exist two kinds of catalytic species in the copolymerization systems.The TGA analyses of the copolymers show that there are two thermal decomposition stages,and the loss of mass in the low thermal decomposition temperature stage decreases with an increase of norbornene content in the copolymer.

关 键 词： 氨基吡啶 镍配合物 蒎烯 降冰片烯 共聚合反应

领　　域： [理学] [理学]