Patent GB-890909-A (GB)
Title: Process for the manufacture of foamed materials of artificial plastics
IPC: C08J9/02
Filed: 1958-05-29
Abstract: Foamed polyacrylic acid amide is manufactured by polymerizing p  the acrylic acid amide either alone or jointly with at most 70% by weight, calculated on the total weight of monomers, of acrylonitrile, acrylic acid or styrene, in acid aqueous solution in the presence of a polymerization catalyst, e.g. ammonium persulphate, either at a pH value within the range of 4 to 7 at a temperature of 50 DEG  to 110 DEG C., or at a degree of acidity ranging from that of sulphuric acid of 0,0005% strength to that of 60% strength, at a temperature of 20 DEG  to 110 DEG C., the polymerization product is pressed under heat and pressure, after removal of water and acid, to form a homogeneous melt and the pressed mass is expanded by heating it at a temperature of 150 DEG -240 DEG C.  The polymerization is preferably conducted in the presence of 0,01 to 15% by weight of the acrylic acid amide of a compound of iron, chromium, vanadium, titanium or manganese. Polyvinyl alcohol may be added to control the speed of the polymerization.  According to an Example (2) to 1 part acrylic acid amide dissolved in 1 part water there was added 0,1 part polyvinyl alcohol, sufficient glacial acetic acid to give a pH of 4 and 0,007 part ferrous sulphate; 0,01 part ammonium persulphate was then gradually added at 50 DEG C.  The rubber-like polymer obtained was treated with methanol, dried and moulded at 120 DEG C. under a pressure of 75 kgs./sq. cm. to form a moulded article which was then heated for 30 minutes at 230 DEG C. to form a foamed material.  In other examples polymers were produced in the presence of ammonium persulphate and ferrous sulphate from (6) 1 part acrylic acid amide and 0,43 part acrylonitrile, (7) 1 part acrylic acid amide and 0,11 part styrene, (8) and (10) 1 part acrylic acid amide, 0,11 part acrylic acid and 0,48 part acrylonitrile, (9) 1 part acrylic acid amide, 0,43 part acrylonitrile and 0,075 part acrylic acid.  While in certain other examples polymerization was conducted in the presence of ammonium persulphate and (11) iron and chromium sulphates, (12) ammonium vanadate, (13) manganese carbonate, (14) ferrous sulphate and ammonium vanadate and (15) ferrous sulphate and titanyl sulphate.ALSO:Foamed polyacrylic acid amide is manufactured by polymerizing the acrylic acid amide either alone or jointly with at most 70% by weight, calculated on the total weight of monomers, of acrylonitrile, acrylic acid or styrene, in acid aqueous solution in the presence of a polymerization catalyst, e.g. ammonium persulphate, either at a pH value within the range of 4 to 7 at a temperature of 50 DEG  to 110 DEG C., or at a degree of acidity ranging from that of sulphuric acid of 0,0005% strength to that of 60% strength, at a temperature of 20 DEG  to 110 DEG C., the polymerization product is pressed under heat and pressure, after removal of water and acid, to form a homogeneous melt and the pressed mass is expanded by heating it at a temperature of 150-240 DEG C.  The polymerization is preferably conducted in the presence of 0,01 to 15% by weight of the acrylic acid amide of a compound of iron, chromium, vanadium, titanium or manganese.  Polyvinyl alcohol may be added to control the speed of the polymerization.  According to an Example (2) to 1 part acrylic acid amide dissolved in 1 part water there was added 0,1 part polyvinyl alcohol sufficient glacial acetic acid to give a pH of 4, and 0,007 part ferrous sulphate; 0,01 part ammonium persulphate was then gradually added at 50 DEG C.  The rubber-like polymer obtained was treated with methanol, dried and moulded at 120 DEG C. under a pressure of 75 kgs/sq. cm. to form a moulded article which was then heated for 30 minutes at 230 DEG C. to form a foamed material.  In other examples, polymers were produced in the presence of ammonium persulphate and ferrous sulphate from (6) 1 part acrylic acid amide and 0,43 part acrylonitrile, (7) 1 part acrylic acid amide and 0,11 part styrene, (8 and 10) 1 part acrylic acid amide, 0,11 part acrylic acid and 0,48 part acrylonitrile, (9) 1 part acrylic acid amide, 0,43 part acrylonitrile and 0,075 part acrylic acid, while in certain other examples polymerization was conducted in the presence of ammonium persulphate, and (11) iron and chromium sulphates, (12) ammonium vanadate (13) manganese carbonate, (14) ferrous sulphate and ammonium vanadate and (15) ferrous sulphate and titanyl sulphate.