Patent GB-390179-A (GB)
Title: Improvements in processes of polymerizing acetylene
IPC: C07C2/38
Filed: 1931-06-22
Abstract: In the process described in the parent Specification, according to which non-benzenoid acetylene polymers are prepared by treating acetylene with an acid catalyst mixture comprising a cuprous salt and a salt of ammonia or of a tertiary amine, there is included in the catalyst mixture an acid or a mixture of acids having an ionization constant of at least 10<-6> and capable of forming a cuprous salt or salts soluble in the catalyst mixture. Specified acids which may be added are hydrochloric, hydrobromic, hydriodic, sulphuric and phosphoric acids, and carboxylic acids such as acetic, chloracetic, formic, propionic, butyric, citric, tartaric and lactic acids.  When an inorganic acid is added, the amount should not exceed that required to give 0,2 per cent of ionized hydrogen, calculated on the copper.  A carboxylic acid, on the other hand, may replace all or any part of the water normally present in the catalyst mixture.  The cuprous salt may be cuprous chloride, bromide, iodide or cyanide; the ammonium or tertiary amine salt may be ammonium chloride or bromide or an acetate, formate, hydrochloride, or hydrobromide of pyridine, quinoline, diethylmetanilic acid, dimethylaniline, diethylaniline, or quinaldine.  The reaction may be effected under pressure.  In the examples, (1) acetylene is passed at about 25 DEG  C. into an aqueous mixture of cuprous chloride, ammonium chloride, copper powder, and hydrochloric acid, and when absorption slackens the product is allowed to stand and then distilled; mono- and di-vinylacetylene and an acetylene tetramer C8 H8 are obtained; (2) as in example 1, using hydrobromic instead of hydrochloric acid; (3) acetylene is passed at 55 DEG  C. through the catalyst of example 1, the emerging gases being passed through a condenser, and the condensed water and unreacted acetylene being returned to the reaction vessel; hydrochloric acid is added from time to time to replace that lost as chlorinated products; (4) as in example 1, using a catalyst comprising pyridine, an excess of acetic or formic acid, cuprous chloride, and copper powder; (5) as in example 4, using lactic instead of acetic acid; (6) as in example 4, with the addition of pyridine hydrochloride to the catalyst; (7) as in example 4, using a catalyst comprising diethylaniline, an excess of formic acid, cuprous chloride, and copper powder.ALSO:In the process described in the parent Specification, according to which non-benzenoid acetylene polymers are prepared by treating acetylene with an acid catalyst mixture comprising a cuprous salt and a salt of ammonia or of a tertiary amine, there is included in the catalyst mixture an acid or a mixture of acids having an ionization constant of at least 10-<6> and capable of forming a cuprous salt or salts soluble in the catalyst mixture.  Specified acids which may be added are hydrochloric, hydrobromic, hydriodic, sulphuric and phosphoric acids, and carboxylic acids such as acetic, chloracetic, formic, propionic, butyric, citric, tartaric, and lactic acids.  When an inorganic acid is added, the amount should not exceed that required to give 0,2 per cent of ionized hydrogen, calculated on the copper.  A carboxylic acid, on the other hand, may replace all or any part of the water normally present in the catalyst mixture.  The cuprous salt may be cuprous chloride, bromide, iodide, or cyanide; the ammonium or tertiary amine salt may be ammonium chloride or bromide or an acetate, formate, hydrochloride, or hydrobromide of pyridine, quinoline, diethylmetanilic acid, dimethylaniline, diethylaniline, or quinaldine.  Catalysts used in the examples are: (1) an aqueous mixture of cuprous chloride, ammonium chloride, copper powder; and hydrochloric acid, (2) as in example 1, but with hydrobromic instead of hydrochloric acid; (3) pyridine, an excess of acetic or formic acid, cuprous chloride, and copper powder; (4) as in (3) but with lactic instead of acetic acid; (5) as in (3) but with the addition of pyridine hydrochloride to the catalyst; (6) diethylaniline, an excess of formic acid, cuprous chloride, and copper powder.