Abstract:
A RUBBER LATEX IS COAGULATED IN THE PRESENCE OF AN AQUEOUS DISPERSION OF FINELY DIVIDED CARBON BLACK, THE DISPERSION BEING FORMED AT A PH OF 1 TO 2. THE COAGULATE MAY THEN BE SUBJECTED TO WASHING, FILTERING AND DRYING AND THE THUS-FORMED GRANULATE MAY SUBSEQUENTLY BE SUBJECTED TO A GRINDING STEP. THE GRANULATE HAS SUBSTANTIALLY NO TENDENCY TO CAKE WITHOUT THE NECESSITY OF ADDING ADDITIONAL SEPARATING AGENTS.
Abstract:
A PREMIX IS MADE FOR INCORPORATION IN A NATURAL OR SYNRHETIC VULCANIZABLE RUBBER MIXTURE OF IMPROVED ADHESION TO TEXTILES BY CONGULATING AN AQUEOUS DISPERSION OF FINELY DIVIDED PRECIPITATED SILICIC ACID OR SILICATE AS A RUBBER LATEX AND MIXING RESORCINOL AND HEXAMETHYLENETETRAMINE AS RESIN-FORMING COMPONENTS INTO THE DRY COGULATE. THE INVENTION ALSO COMPRISES THE VULCANIZABLE PREMIX THUS MADE IN WHICH SPECIFIC AMOUNTS OF SYNTHETIC RUBBER, SILICIC ACID, RESORCINOL AND HEXAMETHYLENETETRAMINE ARE INCORPORATED.
Abstract:
Mixts. of elastomers and silicates as coarse powders contg. 20-90 wt. % silicic acid/silicate with particle size 0.5-1.5mm are obtd. by co-precipitation of aq. elastomer lattices and silicate suspensions with organic acids, pref. formic or acetic, drying and grinding the coagulum. The mixts. are used for mineral-filled rubber applications. Such product mixes process well in the internal mixers, rolls, calenders and injection presses used by the rubber industry. Lengthy washing out of residual salts after pptn is avoided by use of volatile organic acids.