Polymerization of some terminal alkynes by Ziegler-Natta catalyst systems
Fe(RCOO)3-AlEt3
مقال من تأليف: Petit, Alain ; Aouak, Taieb ; Moulay, Saad ;
ملخص: The polymerization of 1-hexyne, 3-methyl-1-pentyne, 4-methyl-1-pentyne, and tert-butylacetylene was carried out with the following Ziegler-Natta type initiating systems: Fe(prp)3-AlEt3, Fe(chc)3-AlEt3, Fe(naph)3-AlEt3 (prp=propionate, chc=cyclohexanecarboxylate, naph=naphtenate). The catalytic efficiency of these complexes was almost identical towards a same monomer. The polymer yield (0-100%) was highly influenced by the bulkiness of the substituent directly attached to a sp carbon. The molecular weights of the different polyalkynes obtained were relatively high (4 x 104-105). 13C and 1H NMR analyses of the polymers revealed a preferential orientation of the polymerization with these initiating systems; that is, the trans-configuration fraction was as high as 70%.
لغة:
إنجليزية