Hardenable, liq., epoxide gp.-contg. graft copolymers (C) are prepd. by a free radical-initiated graft copolymerisation process in organic soln. The reaction batch contains (by wt.) (A) 30-80% liq. epoxide cpds. contg. 1 epoxide gp. per molecule, of viscosity 15-14000 cP at 25 degrees C and epoxide equiv. wt. 120-450, dissolved in inert solvents of b. pt. 40-150 degrees C, and (B) 70-20% mixt. consisting (by wt.), of (a) 2-10% 3-5c ethylenically unsatd. acid and/or its anhydride, (b) 70-93% acrylic acid ester of aliphatic saturated 1-18C monohydric alcohols and (c) 5-25% monohydroxy 2-8 C-alkyl ester of 3-5C alpha, beta-ethylenically unsatd. acids. Reaction batch is kept at 60-150 degrees C until graft copolymerisation is completed. Solvent is opt. distilled off under reduced press. at below 130 degrees C. (C) are used for preparing hardenable, solvent-free or low-solvent coating- and/or moulding compsns.; as casting resins in electrical industry, esp. for embedding temp.-sensitive switch units; as sealing compsns. and in the prepn. of adhesives. (C) can be stored for several months at 40 degrees C and are miscible with epoxide hardeners. Mixts. of (C) and hardeners can be used as solvent-free binders, yielding solvent- and weather-resistant coatings at room temp. Hardened prods. have high impact strength, temp. change stability, weatherability and plasticity also at low temps. In an example, graft copolymer is prepd. from a pentaerythritol/epichlorohydrin epoxide, bu acrylate, hydroxyethyl methacrylate and acrylic acid.
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