Process for producing a crosslinked cellulose ether

[0075] Example

[0076] The present invention will be described in detail in detail below, but will not be construed as limiting the scope of the claims. All parts and percentages are by weight unless otherwise indicated.

[0077] The various terms and naming explanations used in the invention example (Inv.Ex.) and comparative example (Comp.Ex.) are as follows:

[0078] "HEMC" represents hydroxyethylcellulose.

[0079] "AGU" represents a dehydrated glucose unit of cellulose ether.

[0080] "LVN" represents the limit viscosity of the pulp measured as described in the program described in ISO 5351 (2010).

[0081] The various raw materials or ingredients used in the examples are as follows:

[0082] Epilox M 985 is a poly (propanediol) dihydrate glycene ether available from Leuna Harze.

[0083] Examples of the method used in the present invention and crosslinked compounds based on dihydrophil ether are described in Eugenew.jones, "Crosslinking of Cotton Cellulose withdiglycidyl ether", "Applied polymer" Journal of Applied Polymer Science, Volume 18, 714-720 (1961).

[0084] Test Methods

[0085] Insoluble

[0086] The cellulose ether sample was dissolved in water: 1.0 parts by weight of HEMC and 99.0 parts by weight of water. HEMC (dry base) was dispersed in water under stirring at room temperature (about 25 ° C) to avoid forming a gab.

[0087] 50 g of HEMC solution was centrifuged in 13535UPM for 30 minutes in the THEMO Scientific Sorvall Lynx 4000 centrifuge. The insoluble material of the prepared solution ("insoluble material") will be gathered at the bottom of the centrifugal bottle.

[0088] A certain amount of suspended solution was weighed and dried overnight at 105 ° C in a dry box. After the obtained residue, the soluble content is calculated. The insoluble material is subtracted from the initial concentration.

[0089] Examples 1 and 2 and comparative example A-C

[0090] Typically, HEMC is produced in principle based on Williamson ether. After 50% caustic sodium activated, alkalized cellulose is produced. Then the etherification of MCl and EO. For example, useful guidelines of this method are found in R.Donges, "Non-Ionic Cellulose ethers" "," British Polymer Journal "Volume 23, 315- Page 326 (1990). The crosslinked compound used in the process of the present invention is based on a dihydrate glycidyl ether; and an overview of the characteristics of the crosslinking agent used in the examples are described in Table II.

[0091] The limit viscosity (LVN) of the pulp is measured according to the program described in ISO 5351 (2010). The grinding cellulosesis (400 mol; LVN is greater than or equal to (≥) 1,450 ml / grams [ml / g]) is added to a 1,000 liter (L) autoclave (reactor).

[0092] Use n 2 After purging the autoclave three times, heated the autoclave to 40 ° C. Then, dimethyl ether (DME, 4.7 mol / molagu) and the first group of chloride ("MCl 1"; 3.2 mol / mol AGU) were added to the autoclave. The first caustic sodium ("NaOH 1"; (strength of 50%, 1.9 mol NaOH / mol AGU) was added to a mixture in the autoclave at a temperature of 2 minutes at a temperature of 40 ° C. The mixture was maintained at 40 ° C for 30 minutes. The EO (0.45 mol / mol AGU) was then added to a mixture in the autoclave; and the resulting reaction mixture was maintained at 40 ° C for 10 minutes. Then, spray the crosslinking agent to The autoclave reactor.

[0093] The crosslinking agent of the present invention is prepared as an emulsion of water via a thorough mixing of the emulsion to the reactor. The emulsion is then sprayed into the reactor immediately after the emulsion production. In a comparative method, a 100% pure crosslinking agent is sprayed into the reaction mixture in the reactor.

[0094] The substance formed in the reactor was heated to 80 ° C in 45 minutes. The second batch of MCl ("MCl2"; 1.3 mol / mol AGU) was quickly injected at 80 ° C. Then, the second batch of caustic sodium ("NaOH2"; 0.67 mol / mol AGU) was added to 7 parts of the 30 minute period, followed by 70 minutes of cooking time at 80 ° C. After 70 minutes of cooking, the resulting XCE product is formed. The resulting XCE product is then carried out using the conventional procedure known in the art to prepare the resulting XCE product: hot water washing, neutralized with formic acid, using laboratory granulator granulation, drying and grinding.

[0095] Comparative Example A described in Table II, Example 1 and Example 2 Example 2 Example 2 Divided with the method of the present invention, the crosslinking agent is not used in Comparative Example A. The comparative example B and the comparative example C described in Table III are performed using the above comparatively.

[0096] Table II

[0097]

[0098] Add 50% Epilox aqueous emulsion results in a significant increase in viscosity of 1% aqueous solution. At the same time, the amount of insoluble substance is even lower than the level of uncritical comparison examples.

[0099] Table III

[0100]

[0101] When the crosslinking agent was used as a pure additive, the 1% viscosity of the aqueous solution was observed significantly. At the same time, the amount of insoluble substance increases the distribution of the crosslinking agent present in the reactor or uneven distribution.