| 摘要 |
<p>1361045 Foamable sulphonated phenolformaldehyde resins VLADIMIRSKY NAUCHNO-ISSLEDOVATELSKYINSTITUT SINTETICHESKIKH SMOL 6 July 1971 [6 July 1970 (2)] 31532/71 Headings C3C and C3R A foamable plastics composition comprises a mixture of a liquid resole-type phenol-aldehyde condensation product and/or an aldehyde and a nucleus-sulphonated novolak-type resin having on average less than one sulpho group per nucleus. The term "nucleus-sulphonated novolak-type resin" is defined as a material prepared by (a) direct sulphonation of a dehydrated novolak resin or a dihydroxydiphenylalkane by any suitable sulphonating agent; (b) mixing a novolak-type resin with the sulphonated novolak resin or sulphonated dihydroxydiphylalkane prepared as in (a); and (c) mixing a liquid novolak-type phenolaldehyde resin with the product obtained by condensing an arylsulphonic acid and an aldehyde and optionally, urea in such proportions as to obtain an average of not more than one sulpho group per nucleus in the novolaktype resin. The preferred arylsulphonic acids, may be selected from naphthol-, anthracene-, phenol-, benzene, toluene- and naphthalenesulphonic acids. The composition may be foamed by merely mixing the ingredients previously specified at a suitable temperature or by mixing in the presence of a low boiling blowing agent. Suitable blowing agents are petroleum ethers and fluorohydrocarbons. Nitrogenous compounds such as melamine, urea, acrylonitrile, dicyandiamide, m-phenylenediamine, aniline and thiourea may also be added. In the examples foamed plastics are formed from the following binary mixtures:- formalin and a sulphonovolak (11, 29, 34); benzaldehyde and a sulphonovolak (12); trimethylolphenol and a sulphonovolak (7, 8); trimethylolphenol and sulpho - dihydroxydiphenylmethane (9); and a resol and a sulphonovolak (10). Ternary mixtures disclosed in examples are trimethylolphenol, a novolak, and a condensate of phenolsulphonic acid and formaldehyde (1); formalin, a novolak, and a condensate of naphthalenesulphonic acid and formaldehyde (2); benzaldehyde, a novolak and a sulphonovolak (3); trimethylolphenol, dihydroxydiphenylmethane and a condensate of benzenesulphonic acid and acetaldehyde (4); trimethylphenol, a novolak and a condensate of phenolsulphonic acid, urea and formaldate (5); paraform, a novolak and a sulphonovolak (6); a resol, a novolak and a condensate of phenolsulphonic acid, urea and formaldehyde (13-23); and formalin, a novolak, and a condensate of phenolsulphonic acid, urea and formaldehyde (24-28). The preparation of the novolak, sulphonovolak, and resole resins used in the examples is described.</p> |
