Patent GB-474189-A (GB)
Title: Improvements in the vulcanisation of rubber
IPC: C08K5/00
Filed: 1936-12-31
Abstract: The vulcanization of rubber is accelerated by the addition to the mix of quinoline derivatives of the general formula <FORM:0474189/IV/1> where R and R1 may be hydrogen, alkyl, aryl, alkoxy, chlor, thialkyl, amino, alkylamino, arylamino, nitro, hydroxy, or mercapto radicals, and X may be hydrogen, a metal, or a quinolylthio-quinolyl, benzothiazyl, methylol, thiocarbamyl, aromatic acyl, dinitro aryl, thiofuroyl, thiobenzoyl radical.  The preferred compounds are those in which R and R1 are hydrogen or methyl radicals.  References to the literature are furnished describing the preparation of the mercapto quinolines themselves. The quinolyl sulphides containing an alkali metal attached to the sulphur atom are prepared by reacting the mercapto quinoline with an alkali hydroxide.  The alkali metal may be replaced by other metals such as zinc by the addition of a soluble salt of the bivalent metal to the alkali salt.  The disulphides may be prepared by oxidizing the quinolyl sulphides or their alkali salts with ammonium persulphate.  A long list of suitable compounds is given of which the following is typical: 2-mercapto quinoline, 2-mercapto-4 : 8-dimethyl quinoline, zinc quinolyl sulphide, the cyclohexylamine addition product of the zinc salts of 2-mercapto lepidine, and 2-mercapto quinoline (prepared by adding a molar proportion of the amine to the zinc salt in aqueous suspension). Other typical compounds include the alkoxy mercaptoquinolines such as 2-mercapto-6-methoxy quinoline; compounds containing a quinoline nucleus in which the sulphide grouping is substituted, such as quinolyl aromatic thiazyl monosulphides (prepared by reacting an alkali metal salt of a mercapto quinoline with a 1-chlor aromatic thiazole, or by reacting an alkaline mercapto aryl thiazole with a chlor quinoline) such as 2-quinolyl-1-benzothiazyl sulphide; aldehyde derivatives of mercapto quinolines such as the formaldehyde reaction product of 2-mercapto quinoline (prepared by adding formaldehyde to a hydrochloric acid alcoholic solution of 2-mercapto quinoline, and precipitation of the product with water); quinolyl esters of dithiocarbamic and other dithio acids such as the 2-quinolyl ester of dimethyl dithiocarbamic acid (prepared by reacting 2-chlor quinoline with an alkali metal salt of the dithio acid); 2-quinolyl esters of dithiofuroic and dithio benzoic acids and phthaloyl 2-quinolyl sulphides (prepared by reacting the acyl halide with a solution of sodium quinolyl mercaptide.  The accelerators of the present invention may be used either alone or in admixture with basic nitrogen containing accelerators such as diphenylguanidine, and salts thereof.  Other basic accelerators mentioned are ammonia, urea, the amyl primary and secondary amines piperidine, cyclohexylamine, benzylamine, N-ethyl - cyclohexylamine, tetrahydrofurfurylamine, p - p<1> - diamino - diphenylmethane and heptylamine.  Examples are given to show the efficiency of the accelerators in a rubber mix.ALSO:The vulcanization of rubber is accelerated by the addition to the mix of quinoline derivatives of the general formula <FORM:0474189/V/1> where R and R1 may be hydrogen, alkyl, aryl, alkoxy, chlor, thialkyl, amino, alkylamino, arylamino, nitro, hydroxy, or mercapto radicals, and X may be hydrogen, a metal, or a quinolyl, thio-quinolyl, benzothiazyl, methylol, thio-carbamyl, aromatic acyl, dinitro aryl, thio-furoyl, or thiobenzoyl radical.  The preferred compounds are those in which R and R1 are hydrogen or methyl radicals.  References to the literature are furnished describing the preparation of the mercapto quinolines themselves. The quinolyl sulphides containing an alkali metal attached to the sulphur atom are prepared by reacting the mercapto quinoline with an alkali hydroxide.  The alkali metal may be replaced by other metals such as zinc by the addition of a soluble salt of the bivalent metal, to the alkali salt.  The disulphides may be prepared by oxidizing the quinolyl sulphides or their alkali salts with ammonium persulphate.  A long list of suitable compounds is given of which the following is typical: 2-mercapto quinoline, 2-mercapto-4 : 8-dimethyl quinoline, zinc quinolyl sulphide, the cyclohexalamine addition products of the zinc salts of 2-mercaptolepidine, and 2-mercapto quinoline.  Other typical compounds include the alkoxy mercaptoquinolines such as 2 - mercapto - 6 - methoxy quinoline; compounds containing a quinoline nucleus in which the sulphide grouping is substituted, such as quinolyl aromatic thiazyl monosulphides, such as 2-quinolyl-1-benzothiazyl sulphide; aldehyde derivatives of mercapto quinolines such as the formaldehyde reaction product of 2 - mercaptoquinoline; quinolyl esters of dithiocarbamic and other dithio acids such as the 2-quinolyl ester of dimethyl-dithiocarbamic acid ; 2-quinolyl esters of dithiofuroic and dithiobenzoic acids and phythaloyl 2-quinolyl sulphides.  The accelerators of the present invention may be used either alone or in admixture with basic nitrogen containing accelerators such as diphenylguanidine, and salts thereof.  Other basic accelerators mentioned are ammonia, urea, the amyl primary and secondary amines, piperidine, cyclohexylamine, benzylamine, N-ethyl-cyclohexylamine, tetrahydrofurfurylamine, p-p1-diaminodiphenylmethane, and heptylamine.  Examples are given to show the efficiency of the accelerators in a rubber mix.