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研究了添加剂或聚合溶剂对乙炔在Nd(P_(507))_3-Al(C_2H_5)_3及Ti(OBu)_4~-Al(C_2H_5)_3催化体系作用下聚合的影响。结果表明,对于前一催化体系,在无添加剂存在下,用加氢汽油为溶剂只能得到粉末状聚乙炔。但当加入醇类或P_(507)时,在一定的添加剂/Nd克分子比例下,可得到具有金属光泽的聚乙炔膜。研究了聚合物的顺式含量、形态结构、分子量及掺杂后的室温电导率(σ),发现其顺式含量与聚合条件有关,形态结构及σ则与文献报导的用Ti催化体系得到的类似,但分子量则小得多。对于Ti(OBu)_4-Al(C_2H_5)_3体系,改变聚合溶剂或加入给电子试剂,不仅导致催化活性的变化,而且也影响所得聚合物的结构,特别是形态结构。用纯的THF及苯甲醚为溶剂时,得到了文献未见报导的球状或颗粒状形态结构的聚乙炔膜。用碘或其他亲电子试剂掺杂后的这种形态的聚乙炔膜的σ约在100Ω~(-1)cm~(-1)以内,明显比纤维形态的低。对聚乙炔形态结构改变导致σ变化的结果,提出了初步的解释。
The effects of additives or polymerization solvents on the polymerization of acetylene with Nd (P_ (507)) _3-Al (C_2H_5) _3 and Ti (OBu) _4 ~ -Al (C_2H_5) _3 catalysts were investigated. The results show that for the former catalyst system, powdered polyacetylene can only be obtained by using hydrogenated gasoline as solvent in the absence of additive. However, when the alcohol or P_ (507) was added, a polyacetylene film with a metallic luster could be obtained at a certain additive / Nd molar ratio. The cis content, morphological structure, molecular weight and room temperature conductivity (σ) of the polymer were investigated. The cis content of the polymer was found to be related to the polymerization conditions. The morphological structure and σ were compared with those reported in the literature Similar, but the molecular weight is much smaller. For the Ti (OBu) _4-Al (C_2H_5) _3 system, changing the polymerization solvent or adding electron donating reagent not only leads to the change of catalytic activity, but also influences the structure of the obtained polymer, especially the morphological structure. When pure THF and anisole were used as solvent, a polyacetylene film with spherical or granular morphology was not reported in literature. The morphology of polyacetylene films doped with iodine or other electrophilic reagents has a σ within about 100Ω -1 cm -1, which is obviously lower than the fiber morphology. A preliminary explanation is given for the result that the change of the morphology and structure of polyacetylene leads to σ.