摘要:
The invention relates to a method for producing comb polymers, wherein at least one polycarboxylic acid or a salt thereof is esterified with at least one monohydroxy polyether, comprising the following steps: (a) preparing a reaction mixture containing at least one polycarboxylic acid; (b) heating the reaction mixture to at least 80° C.; (c) adding a base; and (d) esterifying the mixture at a reaction temperature of at least 80° C. obtaining a comb polymer, wherein at least one monohydroxy polyether is added to the reaction mixture in step (a) and/or (b). The invention further relates to comb polymers, cement compositions, molded bodies, and uses of comb polymers.
摘要:
Additives selected from primary, secondary, and tertiary alkyl amines and quaternary alkyl ammonium compounds are added to argillaceous gypsum compositions comprising comb polymers to improve the workability thereof. Argillaceous gypsum compositions, dispersing agents, a method for producing argillaceous gypsum compositions, and molded parts that can be produced from the gypsum compositions are also described.
摘要:
A polymer P for prolonging the flowability of water-reduced aqueous hydraulically setting compositions, and a method for prolonging the flowability of water-reduced aqueous hydraulically setting compositions.
摘要:
A polymer P as a dispersant for gypsum compositions, as well as gypsum compositions including the polymer P. The polymer P includes at least one acid unit and at least one long side chain with a molecular weight of at least 1800 g/mol, including polyoxyalkylene groups, and has an acid content of 1.5 to 4 acid groups per gram of polymer.
摘要:
A process is provided for preparing urea-containing polymers by contacting a hydroxy-functional organic compound having a functionality of two or more, with a coupling agent in the presence of a strong base, wherein the coupling agent is a carbonylbislactam compound having the general formula (I): wherein n is an integer from 3 to 15, and that the contacting is conducted at a temperature between 0° C. and 80° C. The polymers thus obtained are believed to be new and are useful e.g. in tissue engineering and coatings applications.