Patent GB-560715-A (GB)
Title: Improvements in or relating to the manufacture of regenerated cellulose films
IPC: D06M15/39
Filed: 1942-05-06
Abstract: Regenerated cellulose films are softened and rendered more flexible by incorporating in them a water-soluble synthetic linear polymer which has a molecular weight above 400 and a boiling point of at least 170 DEG  C. at a pressure of 1 mm. of mercury, and which contains as recurring unit in the molecule an amide, carboxylic ester, amidine, iminoether, urea, quaternary ammonium salt, acetal, ketal, alcohol, sulphonium salt, imine, sulphonamide, carboxylic acid, phosphonamide, urethane, guanidine, ether, or sulphonic acid group.  Compounds containing additional oxygen, nitrogen, SO2, or other hetero atoms or groups in the long molecular chain of atoms may be used, e.g. polymerised triglycol adipamide and glycol diglycolate polyester.  Modified polymers may be used, e.g. products obtained by reaction of an alkylene oxide or glycol formal with acids, amines such as ethanolamine, amides such as formamide, or alcohols such as glycerol.  Mixtures of polyvinyl alcohol with polyethylene oxide, polyethylene oxide with glycerol or urea, or glycol polyformal with glycerol may be used. Dyes may be added to the aqueous softening bath.  The treated films may be used as wrapping material or as bottle capules.  The films may be treated in the course of their production and while they are still in the water-swollen gel state or the dried films may be re-wetted with water and then treated.  In examples, regenerated cellulose films obtained from viscose are treated while in gel state with glycol polyformal, stearic acid-glycol polyformal, cetyl alcohol-glycol polyformal, glycol diglycolate polyester, polyethyleneimine, polyethylene oxide, ethanolformamide and ethylene oxide reaction product, polyvinyl alcohol, a polymerised quaternary ammonium bromide, a polyamidine hydrochloride, a polymerised urea compound, a polymerised sulphonium salt, a polymerised maleic acid-ethylene compound, a polyphosphonamide, polyethylene oxide and glycerol, and a reaction product of monomethyl glycol ether and ethylene oxide. Glycol polyformal is obtained by heating the monomer to 160 DEG  C. for 5 hours in presence of sulphuric acid as catalyst.  Stearic acid-glycol polyformal is obtained by heating stearic acid with glycol formal for 5 hours in presence of an acidic catalyst. Cetyl alcohol-glycol polyformal is made in a similar manner. Ethanolformamideethylene oxide polymer is obtained by passing ethylene oxide into ethanolformamide at 100 DEG  in presence of an alkaline catalyst.  A quaternary ammonium polymer is obtained by heating N.N.N1.N1-tetramethyl decamethylene diamine with p-xylylene dibromide in methanol for a period of 42 hours.  A poly-amidine hydrochloride is prepared by mixing adiponitrile dimethyl di-imino ether dihydrochloride and hexamethylene diamine in methanol and allowing the mixture to stand at room temperature for 48 hours.  A polymeric urea is obtained by heating butyl-diethanolamine and bis-N.N1-methoxymethyl urea at 100 DEG  C. for 3-4 hours, and the polymer is solubilized by treating with hydrochloric acid.  A polymeric sulphonium salt is prepared by dissolving polyhexamethylene sulphide in toluene at reflux temperature and then adding a slight excess of dimethyl sulphate. After the reaction has subsided, the excess of dimethyl sulphate is destroyed by addition of alkali solution.  A polymeric acid is obtained by heating in a bomb at 150 DEG  C., maleic anhydride, ethylene, benzoyl peroxide and xylene.  A polyphosphonamide is obtained by heating phosphoric acid with hexamethylene diamine for 1 hour at 230-260 DEG  C.  A polymeric sulphonic acid is obtained by boiling an aqueous suspension of 1.2-ethanedisulphonyl chloride until the acid chloride disappears; the solution is filtered and concentrated; repeated addition of water and re-evaporation finally gives a syrup from which water is removed by low pressure distillation, the residue is then submitted to distillation under further reduced pressure and ethylene sulphonic acid is obtained as a colourless hygroscopic syrup; the syrup is exposed in a sealed tube to ultra-violet light for several weeks until a soft rubbery, water-soluble polymer is obtained. Specifications 211,446, [Class 2 (ii)], and 461,354, are referred to. The Specification as open to inspection under Sect. 91 comprises also the use of polymeric organic phosphates as softeners for regenerated cellulose films.  A polymeric phosphate may be obtained by allowing ethylene glycol and phosphorus oxychloride to react spontaneously, the mixture being thereafter heated for 4 hours.  This subject-matter does not appear in the Specification as accepted.