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研究了各种催化体系、催化剂浓度及聚合条件对催化效率(f)和聚乙炔分子量()的影响。发现Nd(i-OC_3H_7)-AlR_3(R=C_2H_5,i-C_4H_9)催化体系可获得较大的可溶分数(q)。催化剂浓度、Al/Nd克分子比和聚合温度对f、及q均有一定影响。可溶性Nd(i-OC_3H_7)_3-AlR_3催化体系的UV光谱证实、Nd的价态与AlR_3混合与AlR_3混合后保持不变。PA的IR光谱示出,Nd(i-OC_3H_7)_3-Al(C_2H_5)_3及Nd(i-OC_3H_7)_3-Al(i-C_4H_9)_3体系获得的聚合物分别含有CH_3CH_2—和(CH_3)_2CHCH_2—末端基。上述结果表明,乙炔的聚合可能是通过单体在Nd-C键之间的插入进行的。
The effects of various catalytic systems, catalyst concentration and polymerization conditions on the catalytic efficiency (f) and polyacetylene molecular weight () were investigated. It was found that the larger soluble fraction (q) was obtained for Nd (i-OC_3H_7) -AlR_3 (R = C_2H_5, i-C_4H_9) catalytic system. Catalyst concentration, molar ratio of Al / Nd and polymerization temperature have some influence on f and q. The UV spectra of the soluble Nd (i-OC_3H_7) _3-AlR_3 catalyst confirmed that the valence of Nd remained unchanged after mixing with AlR_3 and AlR_3. The IR spectra of PA show that the polymers obtained from Nd (i-OC_3H_7) _3-Al (C_2H_5) _3 and Nd (i-OC_3H_7) _3-Al (i-C_4H_9) _3 systems contain CH_3CH_2- and (CH_3) _2CHCH_2 - end groups. The above results show that the acetylene polymerization may be through the monomer between the Nd-C bond insertion.