| 摘要 |
Ion exchange or absorbent synthetic resins are made by reacting a mono or polyvalent phenol which may be substituted, with acrylic acid or acrylonitrile and with a cross-linking agent. Specified cross-linking agents are formaldehyde, substances yielding formaldehyde and epichlorohydrin. Specified phenols are phenol, sodium phenol sulphonate, HO-C6H4-CH2-SO3-Na or HO-C6H4-COONa. The reactants may all be condensed simultaneously, the phenol may be precondensed with a quantity of the cross-linking agent insufficient to bring about complete cross-linking, the product being reacted with the acrylic acid or acrylonitrile and then with further cross-linking agent, the phenol may be condensed with sufficient of the cross-linking agent to bring about formation of a resin gel which is condensed with acrylic acid or acrylonitrile. The Examples describe the preparation of resins from :-(1) and (4) sodium cresylo -sulphonate, acrylonitrile, phenol and formaldehyde, (3) sodium phenol sulphonate, formaldehyde, acrylonitrile and phenol, (5) a sulphonated phenol-formaldehyde resin and acrylonitrile or acrylic acid and (6) 3:5-dihydroxybenzoic acid, resorcinol, phenol, formaldehyde and acrylic acid or acrylonitrile. Example (2) describes the after treatment of the resins of Example 1 with methanolic potassium hydroxide or with hydrochloric acid. |
