Bitumens modified by dienophilic cpds - useful as adhesion improvers for bitumen coatings and stabilisers for bitumen emulsions

摘要

Bitumens contg conjugated double bonds are modified by direct contact (pref. at 100-200 degrees C) with dienophilic cpds. (I) contg. C=C-C=O or C=C-C=O groupings or having formula R-CH=CH-Y, Y-CH=CH-Y, R-C=C-X or X-C=C-X (where R is Ph, Me or H; Y is CHO, COOH, COOR, COCl, COR, CN, NO2, SO2R, CH2Cl, CH2NH2, OCOR, Cl OR Br; X is CHO, COOH, COOR, COR or CN). Cpd. nI) is pref. acrylic acid or maleic anhydride and is pref. used in the reaction mixt. in a concn. of 5 wt.%. The products are useful as additives for increasing the adhesion of cut-backs (solvent-diluted bitumens) and surface coatings, and as stabilisers for anionic and cationic bitumen emulsions.