| 摘要 |
1,023,209. Foaming compositions. DOW CORNING CORPORATION. Oct. 19, 1964 [Oct. 28, 1963], No. 42556/64. Headings C3B, C3C, C3P, C3R and C3T. A composition for making foams comprises (1) either organic liquids having a surface tension of at least 22À2 dynes(cm. at 20‹ C. in contact with air, or plastisols, and (2) a copolymer of SiO 2 units and units selected from (CH 3 ) 3 SiO¢ and Q(CH 3 ) 2 SiO¢ units, where Q is a radical containing a solubilizing group to make the copolymer compatable with the material (1), and the ratio of SiO 2 units to the total of the (CH 3 ) 3 SiO¢ and Q(CH 3 ) 2 SiO¢ units is in the range 0À83/1-1À67/1. The organic liquids may be hydrocarbons such as kerosene, saturated and unsaturated acids, alcohols such as methyl alcohol and esters, halohydrocarbons, ethylene oxide, aliphatic, aromatic and heterocyclic ketones, alkyl and aryl amines, triphenylphosphine, allyl isothiocyanate, diethyl carbonate, ethyl mercaptan, benzonitrile, nitroethane, nitrobenzene, paraldehyde, benzaldehyde, furfural, liquid epoxy resins and polyurethanes (together with a blowing agent, e.g. trichlorofluoromethane). As the plastisol may be used polymers of vinyl chloride or copolymers thereof with vinyl acetate in admixture with a high-boiling organic liquid plasticizer which is substantially a non-solvent for the resin at ordinary temperature but is capable of dissolving the resin at elevated temperature to form a single phase material. Organic thinners and diluents may also be used, together with stabilizers and pigments. In the copolymer the group Q may be and The compositions may be foamed by gas introduced mechanically or by the use of blowing agents. Organic liquids used in the examples are methanol, nonane, kerosene, a polyurethane obtained by mixing a tall oil N,N,N<SP>1</SP>,N<SP>1</SP>- tetrakis - 2 - hydroxypropyl)ethylenediamine, and trichlorofluoromethane and then adding diphenylmethanediisocyanate, and an epoxy resin prepared by the reaction of bisphenol A and epichlorhydrin. |
