Patent GB-577205-A (GB)
Title: Improvements in or relating to new synthetic linear condensation polymers
IPC: C08G4/00
Filed: 1943-09-03
Abstract: Synthetic linear condensation polymers having spiro linkages wherein the spiro carbon forms part of a 5- or 6-membered ring are formed by reacting under polymerizing conditions bifunctional spiran-forming or sperain-containing reactants.  Four types of reaction mixture are specified: (1) a mixture of compounds collectively possessing two sets of reactive groups, one of which by reaction with the other forms a linear polymer containing spiro carbon atoms forming part of a 5- or 6-membered ring; (2) a mixture of two mutually reactive bifunctional compounds, one of which contains spiro carbon atoms forming part of a 5- or 6-membered ring; (3) a bifunctional compound containing spiro carbon atoms forming part of a 5- or 6-membered ring and capable of self-condensation; (4) a compound containing two sets of reactive groups which by self-condensation form the desired spiro linkages in the polymer.  Types of chemical linkage which may occur in the products of the invention are ester, amide, thioamide, imidoether, thioimidoether, amidine, urethane, thiourethane, dithiourethane, urea, thiourea, guanidine, ketal, thioether, thioketal, sulphone, sulphonium salt, imine, quaternary ammonium salt and anhydride.  Examples 1 and 2 describe the formation of a polymeric spiro thioketal from tetrakis (mercaptomethyl) methane and cyclohexanedione-1.4 in dioxane solution, through which hydrogen chloride gas was passed.  The product was insoluble in a large number of solvents, and was soluble in boiling naphthalene or boiling anthracene.  Example 3 described the preparation of a similar polymer from tetrakis (mercaptomethyl) methane and dodecanedione-2.11.  The polymer was partially soluble in benzene, the residue being soluble in phenol. Other polymers specifically mentioned are those from 1,4-diamino-cyclohexane-1.4-dicarboxylic acid, or from 1,4-dihydroxy-cyclohexane-1.4-dicarboxylic acid by self-condensation and that from hexamethylene glycol and spiroundecane dicarboxylic acid.  Spirothioketals and spirothioacetals are also generally referred to as being obtained from, e.g. tetrakis (mercaptomethyl) methane and dicarboxyl compounds such as acetylacetone; acetonyl acetone; octadione-2,7; diacetobenzene; benzoylacetone; cyclopentanedione; succinic dialdehyde; adipic dialdehyde; or terephthaldehyde.  In place of tetrakis (mercaptomethyl) methane may be employed any organic compound having a quaternary carbon atom joined to four alkyl groups, each of which has a mercaptan group on the carbon atom next to the quaternary carbon atom.  If desired, the reaction may be carried out by melting the reactants together with an acid catalyst, or solvents other than dioxane may be employed as reaction medium, e.g. benzene "Cellosolve" (Registered Trade Mark), cyclohexane, anthracene, thiophene, furane, tetrahydrofurane, phenol, or cyclohexanol.  Suitable catalysts other than hydrogen chloride are sulphur dioxide, sulphur trioxide, aluminium trichloride, boron trifluoride, hydrogen bromide, hydrogen fluoride or toluene sulphonic acid.  The products may be used for textile films, monofils for bristles, transparent sheeting or for coating fabrics.  U.S.A. Specificatio 2,071,250 is referred to.