| 摘要 |
A foamed adhesive comprises a thermosetting aldehyde resinous condensate suspended or dissolved in water and a foam stabilizing cationic quaternary salt with at least one of its substituent groups as an aliphatic radical of at least nine carbon atoms. The stabilizer content is 0,2% to 3,0% by weight of the resin and has the general formula <FORM:0887078/IV (a)/1> where Y is nitrogen, phosphorous or arsenic, X is an anion usually chlorine, R is alkyl, substituted alkyl, aryl or substituted aryl and R1 is an aliphatic radical having at least nine carbon atoms. The foam stabilizing agents specified are alkyl trimethyl ammonium chloride; R1- tolyl methyl trimethyl ammonium chloride where R1 is C9H19 to C15H31; 1-(2-hydroxyethyl) -2-hepta decenyl-1(or -3)-benzyl-2-imidazolinium chloride. R1 may be connected to a heterocyclic structure as indicated by the dotted line in the above formula. The resins in the A or B stage are used in the form of aqueous dispersions with an adhesive solids content of 15% to 60% by weight. Foaming is effected by whisking or beating for 10-30 minutes with a gas such as nitrogen, air or "Freons" ("Freon" is a Registered Trade Mark). To produce a foam of the required specific gravity of 0,1 to 0,6 the viscosity of the composition is controlled by the addition of thickeners such as carboxy methyl cellulose, alginates, natural gums such as karaya and gum arabic, or fillers such as wood flour. The bubble size of the foam is between 20m and 300m with a foamed volume of two to nine times the original volume. Catalysts such as paraformaldehyde or hexamethylene tetramine may also be added to the composition.ALSO:A foamed adhesive comprises a thermosetting aldehyde resinous condensate suspended or dissolved in water and a foam stabilising cationic quaternary salt with at least one of its substituent groups as an aliphatic radical of at least nine carbon atoms. The stabiliser content is 0,2% to 3,0% by weight of the resin and has the general formula <FORM:0887078/V/1> where Y is nitrogen, phosphorus or arsenic, X is an anion usually chlorine, R is alkyl substituted alkyl, aryl or substituted aryl, and R1 is an aliphatic radical having at least nine carbon atoms. The foam stabilising agents specified are alkyl trimethyl ammonium chloride; R1 tolyl methyl trimethyl ammonium chloride where R1 is C9H19 to C15H31; 1-(2-hydroxyethyl)-2-hepta decenyl-1 (or -3)-benzyl-2-imidazolinium chloride. R1 may be connected to a heterocyclic structure as indicated by the dotted line in the above formula. The resins in the A or B stage are used in the form of aqueous dispersions with an adhesive solids content of 15% to 60% by weight. Foaming is effected by whisking or beating for 10-30 minutes with a gas such as nitrogen, air or Freons ("Freon" is a Registered Trade Mark). To produce a foam of the required specific gravity of 0,1 to 0,6 the viscosity of the composition is controlled by the addition of thickeners such as carboxy methyl cellulose, alginates, natural gums such as karaya and gum arabic, or fillers such as wood flour. The bubble size of the foam is between 20m and 300m with a foamed volume of two to nine times the original volume. Catalysts such as paraformaldehyde or hexamethylene tetramine may also be added to the composition. |
