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合成了不同Nd含量的聚(乙烯-丙烯酸)钕(EAA·Nd)。元素分析和红外光谱表明,EAA·Nd中不再含氯,并且Nd是与COO~-相连的。由v_(as)COO~-和v_s COO~-振动频率差和COO~-的O1s电子结合能谱数据可以认为COO~-和Nd成键形成具有双配位键的结构(B)。 由EAA·Nd组成的催化体系对丁二烯聚合具有较高的催化活性。在Nd/—COOH(摩尔比)=0.17时活性最高。当Cl/Nd(原子比)=3时,活性最高,聚丁二烯的特性粘数最小,随着Al/Nd(摩尔比)的增加,催化活性逐渐提高。聚丁二烯的顺-1,4含量不受Cl/Nd和Al/Nd的影响,顺-1,4含量大于98％。丁二烯在不同溶剂中的聚合速度明显不同,在己烷中的聚合速度大大高于在芳香烃溶剂中的聚合速度,发现随着芳香烃溶剂碱性的增加,聚合速度逐渐降低,这是由于芳香溶剂和单体对催化剂Nd竞争配位的结果。
Poly (ethylene - acrylic acid) neodymium (EAA · Nd) with different Nd content was synthesized. Elemental analysis and infrared spectroscopy showed that chlorine was no longer contained in EAA · Nd and Nd was linked to COO ~. It can be considered that COO ~ - and Nd are bonded to form a structure (B) with double coordination bonds, which is based on the difference of the vibration frequencies of v_ (as) COO ~ - and v_s COO ~ - and O1s electron coupling energy spectra of COO ~ The catalytic system composed of EAA · Nd has higher catalytic activity for butadiene polymerization. The activity was the highest at Nd / -COOH (molar ratio) = 0.17. When Cl / Nd (atomic ratio) = 3, the activity was the highest and the intrinsic viscosity of polybutadiene was the smallest. With the increase of Al / Nd ratio, the catalytic activity increased gradually. The cis-1,4 content of polybutadiene is not affected by Cl / Nd and Al / Nd, cis-1,4 content is greater than 98%. The rate of polymerization of butadiene in different solvents is significantly different, the rate of polymerization in hexane is much higher than that in aromatic solvents, and the rate of polymerization decreases as the alkalinity of the aromatic hydrocarbon solvent increases As a result of the aromatic solvent and monomer competitive catalyst Nd coordination results.