Process for the production of a substantially equimolecular copolymer of maleic acid anhydride and diisobutylene
Abstract
Abstract An improved process for the production of a substantially equimolecular copolymer of maleic acid anhydride and diisobutylene in which from 10 to 100 mole % of the anhydride groups are esterified with linear or branched aliphatic monoalcohols containing from 1 to 20 carbon atoms or with cycloaliphatic monoalcohols containing from 5 to 6 carbon atoms to form the corresponding semiesters, wherein shortly before or after the end of the solution or suspension copolymerization of maleic acid anhydride and diisobutylene a monomer corresponding to the general formula ##STR1## in which R=H, CH 3 , C 2 H 5 , --OR 2 , --O--CO--CH 3 , ##STR2## --CH 2 OH, --CH 2 O--C--CH 3 , R 1 =H , CH 3 and R 2 =a linear or branched alkyl group containing from 1 to 4 carbon atoms, Or mixtures of these monomers with one another are added to the polymerization mixture in quantities of from 1 to 12 mole %, based on the maleic acid anhydride used. The aqueous or aqueous-alcoholic alkali, amine or ammonium salt solutions of the semiesters of the copolymer are highly effective as anionic sizing agents for paper.
Inventors
- 👤 Gunter Sackmann
- 👤 Gunter Kolb
- 👤 Heinz Fischer
- 👤 Friedhelm Muller
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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