Degussa Aktiengesellschaft

Dietmar Bischoff

Reinhard Stober

Michael Huss

Ellen Kohn

Wolfgang Fischer

Gert Roessler

The invention relates to a method of preparing an adjustable-viscosity cationized starch in which, in a process step in the presence of 10 to 35 wt. % water and preferably 0.01 to 2.00 wt. % of a finely-divided silica and/or silicate (in each case relative to the total amount of mixture) the starch is homogenized with an alkaline oxide, hydroxide, silicate aluminate or mixtures thereof, an alkylene epoxide and a peroxo compound or a mixture of at least two peroxo compounds and then boiled in known manner at the desired time.

Method of manufacturing an adjustable-viscosity cationic starch

A process for the dry cationization of polyvinyl alcohol (PVA) by reaction of alkylidene epoxides with PVA in alkaline medium in the presence of water, in which the reaction mixture contains 11 to 30 weight % of water, based on its total amount, and 1 to 4 weight % of an alkali metal or alkaline earth metal hydroxide or alkaline earth metal oxide, based on the quantity of PVA. As the cationizing agent there are used alkylidene epoxides or their mixtures having the general formula: ##STR1## wherein n=1, 2 or, 3, R.sup.1, R.sup.2 and R.sup.3 represent the same or different alkyl residues having 1 to 18 carbon atoms or R.sup.1 represents the benzyl or --C.sub.2 H.sub.4 OH, and X.sup.- denotes chloride, bromide, sulfate or acetate. Instead of alkylidene epoxides, the corresponding halohydrins, e.g. chlorohydrin or bromohydrin, can be used.

Process for dry cationization of polyvinyl alcohol

A method for preparing cellulose ethers containing tertiary or quaternary nitrogen by reacting alkylene epoxides with cellulose or its derivatives in an alkaline medium in the presence of water. Alkylene epoxides of the formulas ##STR1## or mixtures thereof, in which n=1, 2 or 3, R.sup.1, R.sup.2 and R.sup.3 correspond to the same or different alkyl groups with 1 to 18 carbon atoms or R.sup.1 corresponds to the benzyl group or --C.sub.2 H.sub.4 OH and X is chloride, bromide, sulfate or acetate are used as cationization agents.

Method of preparing cellulose ethers containing tertiary or quaternary

A process for the preparation of cationized polyvinyl alcohol (PVA) by reaction of alkylidene epoxides with PVA in alkaline medium in the presence of water, in which the reaction mixture contains 11 to 30 weight % of water, based on its total amount, and 1 to 4 weight % of an alkali metal or alkaline earth metal hydroxide or alkaline earth metal oxide, based on the quantity of PVA. As the cationizing agent there are used alkylidene epoxides or their mixtures having the general formula ##STR1## wherein n - 1, 2 or 3, R.sub.1, R.sub.2 and R.sub.3 represent the same or different alkyl residues having 1 to 18 carbon atoms or R.sub.1 represents the benzyl or --C.sub.2 H.sub.4 OH, and X.sup.- denotes chloride, bromide, sulfate or acetate.

Growing community of inventors

Marktbreit, Germany

Dietmar Bischoff