Adhesive composition comprising starch, maleic anhydride tripolymer and hydrolized polyacrylonitrile

Claim 1

A SINGLE-PACKAGE DRY MIX COMPOSITION ADAPTED TO BE CONVERTED TO AN ADHESIVE UPON BEING STIRRED INTO AQUEOUS ALKALI, WHICH MIX COMPRISES DRY, UNCOOKED STARCH, FROM ABOUT 0.5 TO 3%/WT. ON THE TOTAL OF SAID DRY MIX COMPOSITION OF AN INSOLUBLE SUSPENDING AGENT WHICH IS READILY DISPERSIBLE IN AQUEOUS ALKALI AND SELECTED FROM THE CLASS CONSISTING OF AN INSOLUBLE MALEIC ANHYDRIDE TRI POLYMER, ITS PARTIAL ESTER DERIVATIVES IN WHICH FROM 5 TO 85% OF ITS ANHYDRIDE LINKAGES HAVE BEEN OPENED BY REACTION WITH MONOHYDRIC ALCOHOL, AND ITS PARTIAL AMIDE DERIVATIVES IN WHICH FROM 5 TO 85% OF ITS ANHYDRIDE LINKAGES HAVE BEEN OPENED BY REACTION WITH AN AMINE CONTAINING A SINGLE AMINO GROUP PER MOLECULE, SAID TRIPOLYMER BEING FORMED BY THE POLYMERIZATION OF A MONOMERIC MATERIAL COMPRISING (1) MALEIC ANHYDRIC, (2) AN ALKYL VINYL ETHER CONTAINING FROM 3 TO 6 CARBON ATOMS AND (3) A CROSS-LINKING MONOMER HAVING MORE THAN TWO NON-CONJUGATED CH2=C< GROUPS PER MOLECULE AND SELECTED FROM THE CLASS CONSISTING OF TRIVINYL BENZENE, HEXAALLYL TRIMETHYLENE TRISULFONE, TRIMETHACRYLYL TRIAZINE, 1,3,5-TRIALLYL ETHER OF TRIHDROXYBENZENE, AND THE VINYL, ALLYL, METHALLYL AND CROTYL POLYETHERS OF ALIPHATIC POLYHYDROXY COMPOUNDS WHICH CONTAIN AT LEAST 3 HYDROXY GROUPS AND AT LEAST 4 CARBON ATOMS, THE SUM OF THE PROPORTIONS OF SAID MONOMERS (2) AND (3) BEING ABOUT EQUIMOLAR WITH THAT OF THE SAID MALEIC ANHYDRIDE AND SAID MONOMER (3) CONSTITUTING FROM ABOUT 0.1 TO 2.5%/WT. OF SAID MONOMERIC MIXTURE, AND 0.2 TO 1%/WT. ON THE TOTAL WEIGHT OF SAID DRY MIX COMPOSITION OF A SOLID, GRANULAR, ALKALI-SOLUBLE HYDROLYZED POLYACRLONITRILE.