It is quite known already to prepare acetylene polymers by using a catalytic system consisting of a compound of a transition metal and of an organometal compound of the elements of groups 1A, 2A, and 3A of the Periodic System.
A preparation of this type is found described for the first time by G. NATTA et al. in 'Rend. Acc. Naz. Lincei, Scienze Fis. Mat. Nat.: 25, 3 (1958), according to which crystalline acetylene polymers are obtained in the form of a powder by using catalysts based on titanium and aluminum trialkyl alcoholates.
More particularly there is known the possibility of obtaining the polyacetylene directly in the polymerization in the form of a film (T. Iyo, H. Shirakawa & S. Ikeda, J. Polym. Sci. Polym. Chem., Ed. 13, 11 (1974).
This method is preferred in general even if with the same it is not possible to obtain films with good mechanical properties.
In the published Italian Patent Appl. No. 22722 A/82 there are described new polyacetylene films endowed with particular characteristics, such as the elongation at break, the breaking load and the molecular orientation under stretch. Such films are prepared by using as catalysts special titanium compounds, mainly dialcoxy-dicresoxy titanium in combination with aluminum trialkyls. In general, the values of apparent density of the polyacetylene prepared according to the known methods of the Prior Art prove to be comprised between 0.4 and 0.5 g/cc, with values of the surface area greater than 70 m.sup.2 /g.
A considerable drawback of the polyacetylenes prepared so far is represented by their instability to oxidation, which considerably reduces the possibility of their being used, for instance, in the manufacture of electrodes for primary and secondary batteries.