_-= 2,41%,605 Patented Nov. 5, 1946 ~r orrrca STATES I we 2,410,605 INTERPOLYMERS OF :ISOBUTYLENE WITH AN ALKYL ACETYLENE AND THEIR PREP eaa'rrou - Denis William Huebner and James Edgar Fearey, ' Norton-on-Tees, England, assignors to Hm periai Chemical Industries Limited, a corpora tion of Great Britain No Drawing. Application my 1a, 1943, Serial No. 487,537. In Great Britain May 18, 1942 i5 Claims. (Cl. 266-92) 2 E . aluminium chloride. , .cess of methyl alcohol was added to the product, whereupon the polymer formed in the reaction was precipitated as a sticky semi-solid. / This was It is already known that'isobutylene and other iso-ole?nes can be polymerised to form products of high molecular weight, by subjecting them at temperatures below about —10° 0., to the action of. inorganic halides such as boron ?uoride and further washed with methanol and then dried in an oven at about 100° C. The product was a somewhat tacky, rubber-like solid which resem bled polyisobutene of low molecular weight. The - We have now found that interpolym'ers of iso ole?nes such as isobutylene with alkyl acetylenes, -.molecular weight as determined by the Staud inger viscosity method was 3,000 and the iodine can be produced by subjecting a mixture con-‘ taining an lso-ole?ne and one or more alkyl 10 value was 46.5 gms. iodine/100 gms. which corre- . sponds to ‘7.3% methyl acetylene in the inter acetylenes ‘to the action of a catalyst of the Friedel-Crafts type, at a temperature below —10° C. - polymer. -1. A process for the production of an inter Operating conditions similar to those known for the polymerisation or iso-ole?nes may be em I ' We claim: \ 15 polymer of isobutylene and methyl acetylene which comprises subjecting a mixture contain ing isobutylene and methyl acetylene to the‘ ac tion of boron tri?uoride at a temperature below. ployed. The, molecular weights of the lnterpoly mers ‘vary with the'reaction conditions such as _ temperature, presence or absence of solvent, . amount and nature of the catalyst, in a ‘manner ' —10° C. similar to that already known for the polymeriza 20 2. A process for the production or an inter polymer of isobutylene and methyl acetylene tion of iso-ole?ns per se. In addition the molec which‘comprises subjecting a mixture containing ular weight and yield have been found to fall as isobutylene and methyl acetylene to the action ' the proportion of the iso-ole?ne in the inter-poly of ' aluminium chloride at a temperature below mer'decreases, other operating conditions being the same. - 25 —10° C. . 3. A process for the production ‘of an inter Example A mixture consisting of 2 parts by volume of _ liquid methyl acetylene, 18 parts isobutene, —60v polymer of isobutylene and methyl acetylene which comprises subjecting a. mixture containing isobutylene and methyl acetylene to the action parts pure petroleum ether, was placed'in a 30 of a Friedel-Crafts catalyst at a temperature be stirred glass vessel cooled to about _—80° C., in a low ¢-10° C. . ~. , ' bath of methanol and solid carbon dioxide. A 4. A process for the production of an inter > quantity of powdered solid carbon dioxide was polymer of_ isobutylene and methyl acetylene which comprises subjecting a mixture containing stirredvigorously. Su?icient solid carbon dioxide 35 isobutylene and methyl acetylene to the action of was added so that a slight excess'remained after a, Friedel-Cratts catalyst at a temperature not the polymerisation. 100 parts by volume of gase exceeding —80° C. ,. I ous boron tri?uoride were then rapidly passed \5. :The process according to claim 4 wherein the through the mixture whereupon vigorous poly merisation took place, most of the solid carbon 40 FriedeLCraits catalyst is boron tri?uoride. 6. An interpolymer oi isobutylene and methyl dioxide being vaporised by. the heat of the re then added to the reaction mixture which was acetylene. action. ' . Throughout the reaction, the temperature re malned at —'82° C. After polymerisation, an ex > ' DENISWIILIAMHUEBNE'RY, ‘J'AMES EDGAR FEAREY.