Process of preparing alkylhydroxyalkylcellulose

Details Process of preparing alkylhydroxyalkylcellulose Process of preparing alkylhydroxyalkylcellulose

2008-07-22

2008-07-22

Jiang, Shaojia Anna (Department: 1623)

Organic compounds -- part of the class 532-570 series

Organic compounds

Carbohydrates or derivatives

C536S056000, C536S084000, C536S090000, C536S091000, C536S095000, C536S096000, C536S099000, C536S100000

Reexamination Certificate

active

10197070

ABSTRACT:
A process of preparing alkylhydroxyalkylcellulose (e.g., methylhydroxyethylcellulose and methylhydroxypropylcellulose) by reaction of cellulose in the presence of alkali metal hydroxide with an alkylating agent and a hydroxyalkylating agent is described. The process includes: (a) alkalizing cellulose by means of 0.9 to 2.9 equivalents of an alkali metal hydroxide I/AGU of the cellulose in the form of an aqueous alkali metal hydroxide solution, in the presence of a suspension medium containing at least 0.2 equivalents of an alkylating agent I/AGU of the cellulose; (b) reacting the alkalized cellulose of step (a) with alkylating agent I and a hydroxyalkylating agent at a temperature above 65° C.; (c) adding additional alkali metal hydroxide 11 in the form of an aqueous alkali metal hydroxide solution; and (d) adding additional alkylating agent 11 in an amount of at least the absolute value of the difference between (i) the number of equivalents of alkylating agent I/AGU of the cellulose already added, and (ii) the total number of equivalents of alkali metal hydroxide/AGU of the cellulose added. Additional alkylating agent 11 is not added in step (d) if (i) the number of equivalents of alkylating agent I/AGU of the cellulose already added exceeds (ii) the total number of equivalents of alkali metal hydroxide/AGU of the cellulose already added. In a further step (e), the alkylhydroxyalkylcellulose is isolated from the reaction mixture. The isolated alkylhydroxyalkylcellulose may be optionally purified.

REFERENCES:
patent: 2949452 (1960-08-01), Savage
patent: 3819593 (1974-06-01), Glomski et al.
patent: 3839319 (1974-10-01), Greminger, Jr. et al.
patent: 4096325 (1978-06-01), Teng et al.
patent: 4460766 (1984-07-01), Felcht et al.
patent: 4477657 (1984-10-01), Strange et al.
patent: 4547570 (1985-10-01), Garner
patent: 4650863 (1987-03-01), Felcht et al.
patent: 5166333 (1992-11-01), Breckwoldt
patent: 5493013 (1996-02-01), Reichel
patent: 6235893 (2001-05-01), Reibert et al.
patent: 6891034 (2005-05-01), Dannhorn et al.
patent: 2002/0038018 (2002-03-01), Dunnhorn et al.
patent: 39 09 070 (1990-09-01), None
patent: 0 385 881 (1998-04-01), None
Houben-Weyl, Methoden der Organischen Chemie, Makromolekulare Stoffe, 4thed. vol. E20 (month unavailable) 1987, pp. 2042-2074, “Polysaccharid-Derivate”, Dr. Konrad Engelskirchen.
Patent Abstracts Of Japan vol. 1998, No. 11, Sep. 30, 1998 & JP 10 158302 A Week 199834 Derwent Publications Ltd., GB; AN 1998-393478 Zusammenfassung.
JP 60 192702 A (Shinetsu Kagaku Kogyo KK), Oct. 1, 1985 Zusammenfassung & Database WPI Week 198545 Derwent Publications Ltd., London, GB; AN 1985-280998 Zusammenfassung.
G. Bartelmus and R. Keterer, Z. Anal. Chem 286 (1997) 161-190.

Affiliated with

Also associated with

Rating

Process of preparing alkylhydroxyalkylcellulose does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process of preparing alkylhydroxyalkylcellulose, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process of preparing alkylhydroxyalkylcellulose will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3934005