Patent GB-738047-A (GB)
Title: Sulfonated methylol acrylamide polymers and copolymers and their preparation
IPC: C08F8/34
Filed: 1953-04-30
Abstract: Sulphonated anionic polymers are prepared by polymerizing acrylamides having the formula <FORM:0738047/IV (a)/1> wherein R is hydrogen or an alkyl radical having from 1 to 4 carbon atoms, the acrylamide being condensed before or after polymerization with formaldehyde or a formaldehyde engendering compound, e.g. paraformaldehyde or hexamethylene tetramine, whereby the corresponding N-methylol acrylamide is formed, and reacting the resulting polymer with sulphurous acid or a water-soluble salt thereof under such conditions that the residue of the sulphurous acid is linked to the amido nitrogen atom through a methylene group, the molar ratios of formaldehyde and sulphurous acid to the acrylamide being at least 0.05/1 on a monomeric basis.  When the acrylamide is polymerized prior to treatment with formaldehyde such treatment may be carried out prior to or simultaneously with the sulphurous acid treatment, e.g. the acrylamide polymer may be treated with the condensation product of formaldehyde and sulphurous acid.  In a modification of the process N-methylol acrylamide or methacrylamide is copolymerized with a hydrophobic monomeric compound having a vinylidene grouping and a boiling point of at least 60 DEG  C., such as vinyl acetate, vinyl propionate, methyl, ethyl, and n-octyl acrylates, methyl methacrylate, acrylonitrile, styrene, p-chlorostyrene, alpha-chlorostyrene, p-methylstyrene, and alpha-methylstyrene, and the resulting copolymer is then reacted with sulphurous acid or a water-soluble salt thereof.  The polymerization or copolymerization of the acrylamide or N-methylol acrylamide is carried out in an aqueous medium with the aid of a catalyst such as hydrogen peroxide, potassium and sodium peroxides and persulphates, sodium perborate, a complex catalyst made from a ferrous or ferric salt and hydrogen peroxide, peracetic acid, urea peroxide, benzoyl, lauryl, and acryl peroxides, and tert.-butyl hydroperoxide, and optionally an emulsifier such as diamyl, dihexyl, or dioctyl sulphosuccinic esters and salts thereof, lauryl sulphate, sulphonated oils, glycol oleates and linoleates, mineral oil sulphonates, aromatic sulphonates, wax acid soaps, triethanolamine oleate, monoglycerol linoleate, amino sulphonates and sulphates, ammoniacal and alkaline caseins, soaps, lecithin, cholesterol, saponin, gum arabic, and glycerin.  The reaction mixture may have a pH of from 2 to 11, and may also contain a water miscible alcohol such as ethyl and isopropyl alcohols.  The products may be used for soil conditioning, and as oil well drilling fluids, anti-static agents for fibres, and surface active agents.ALSO:N-Methylol acrylamides are prepared from acrylamides of the formula <FORM:0738047/IV (b)/1> where R is hydrogen or an alkyl radical of 1 to 4 carbon atoms by reaction with formaldehyde, or a substance engendering formaldehyde, e.g. hexamethylenetetramine or paraformaldehyde. The reaction is preferably carried out at a pH of between 6 and 11, and at a temperature of between 20 DEG  and 100 DEG C.ALSO:As soil conditioners there are used polymers and copolymers of N-methylol acrylamide or a derivative thereof substituted on the alpha carbon atom with an alkyl group of 1 to 4 carbon atoms, which has been sulphonated by treatment with sulphurous acid or a water-soluble salt thereof.