Organic compounds -- part of the class 532-570 series – Organic compounds – Oxygen containing
Reexamination Certificate
2001-05-04
2002-12-17
Barts, Samuel (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Oxygen containing
C568S616000, C568S622000
Reexamination Certificate
active
06495727
ABSTRACT:
TECHNICAL FIELD
The present invention relates to an industrial process for preparing low-foaming nonionic surfactants and more particularly to a process for preparing ether-capped poly(oxyalkylated) alcohol surfactants which have superior spotting and filming benefits in dishwashing and hard surface cleaning applications, as well as suds suppression in detergent compositions.
BACKGROUND OF THE INVENTION
Ether-capped poly(oxyalkylated) alcohols can be prepared using various catalysts, such as Lewis acids. However, for industrial production, metallic catalysts, such as stannic chloride is preferred. In addition to being an excellent catalyst for the reaction of a glycidyl ether with ethoxylated alcohol, metallic catalysts are economical and readily available in commercial bulk quantities. They also offer safety and ease of handling advantages on an industrial scale versus alternative catalysts. One important disadvantage for metallic catalysts is that the soluble metallic residue component of the catalyst, such as tin residues when is the catalyst SnCl
4
, resulting from there use as reaction catalyst, generally cannot be tolerated above about 100 ppm in many cleaning formulations and applications and these residues are difficult and expensive to remove from ether-capped poly(oxyalkylated) alcohol compositions. Successful laboratory approaches to removal of residual metallic catalyst component, such as the use of a silica gel plug and eluting with a 5% methanol in dichloromethane solution leads to complexity and high cost on an industrial production scale. Due to the surfactant properties of the ether-capped poly(oxyalkylated) alcohol, water washing for metallic catalyst component removal leads to emulsification problems leading to complex organic—aqueous separations.
Problems can also arise in the formation of color impurities, caused by the reaction of color forming bodies, in the end product. These color forming impurities or bodies result in a finished product which is undesirable to consumers and consequently unusable because of its appearance. Thus, the synthesis of ether-capped poly(oxyalkylated) alcohol surfactants is not straightforward and can be surprisingly problematic.
Accordingly, the need remains for a simple, inexpensive yet effective process for the production of ether-capped poly(oxyalkylated) alcohol surfactants which does not result in colored impurities in the final product.
BACKGROUND ART
U.S. Pat. Nos. 4,272,394, issued Jun. 9, 1981, 5,294,365, issued Mar. 15, 1994, 4,248,729, issued Feb. 3, 1981; 4,284,532, issued Aug. 18, 1981; 4,627,927, issued Dec. 9, 1986; 4,790,856, issued Dec. 13, 1988; 4,804,492, issued Feb. 14, 1989; 4,770,815, issued Sep. 13, 1989; 5,035,814, issued Jul. 30, 1991; 5,047,165, issued Sep. 10, 1991; 5,419,853, issued May 30, 1995; 5,294,365, issued Mar. 15, 1994; GB Application No. 2,144,763, published Mar. 13, 1985; GB Application No. 2,154,599, published Sep. 9, 1985; WO Application No. 9,296,150, published Apr. 16, 1992; WO 94/22800, published Oct. 13, 1994, WO 93/04153, published Mar. 4, 1993, WO 97/22651, published Jun. 26, 1997, EP Application No. 342,177, published Nov. 15, 1989 and “Glyceryl Bisether Sulfates. 1: Improved Synthesis” Brian D. Condon; Journal Of the American Chemical Society, Vol. 71, no. 7 (July 1994).
SUMMARY OF THE INVENTION
A process for production of ether-capped poly(oxyalkylated) alcohol surfactants which does not result in colored impurities in the final product has been discovered that is simple and economical to practice on an industrial scale. It has been discovered that the use of a basic catalysts, such as Lewis bases, and then following the reaction with a bleaching step can be used to produce poly(oxyalkylated) alcohol surfactants which does not result in colored impurities while avoiding oil and water phase emulsification during work-up and product isolation. This method avoids organic solvents, costly process aids, process complexity and removes the need to remove any metallic catalyst component residues, typically associated with the use of Lewis acid catalysts. This bleaching can be carried out as either a batch or continuous process. Furthermore, the bleached product can be removed in a single or multiple extraction steps.
In accordance with a first aspect of the present invention, a process for preparing an ether-capped poly(oxyalkylated) alcohol surfactant is provided. The surfactant has the formula:
R
1
O[CH
2
CH(R
3
)O]
x
CH
2
CH(OH)CH
2
OR
2
wherein R
1
and R
2
are linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon radicals having from about 1 to about 30 carbon atoms; R
3
is H, or a linear aliphatic hydrocarbon radical having from about 1 to about 4 carbon atoms; x is an integer having an average value from 1 to about 30, wherein when x is 2 or greater, R
3
may be the same or different, independently H, or C
1
to C
4
in any given molecule, further wherein when x is 15 or greater and R
3
is H and methyl, at least four of R
3
are methyl, further wherein when x is 15 or greater and R
3
includes H and from 1 to 3 methyl groups, then at least one R
3
is ethyl, propyl or butyl, further wherein R
2
can optionally be alkoxylated, wherein said alkoxy is selected from ethoxy, propoxy, butyloxy and mixtures thereof. The process comprises the steps of:
(a) providing a glycidyl ether having the formula:
wherein R
2
is defined as above;
(b) providing an ethoxylated alcohol having the formula:
wherein R
1
, R
3
and x are defined as above; and
(c) reacting the glycidyl ether with the ethoxylated alcohol to form the surfactant in the presence of a basic catalyst;
(d) optionally, said surfactant is sparged with an inert gas, preferably N
2
, Ar and mixtures thereof, optionally under vacuum, preferably a vacuum in the range of 5 to 500 mmHg; and
(e) the product of step (d) is bleached with an about 0.05% to about 5.0%, preferably about 0.1% to about 1.0%, by weight solution of a bleach at a temperature from about 25° C. to about 95° C.
R
1
and R
2
are preferably a linear or branched, saturated or unsaturated, aliphatic hydrocarbon radical having from about 6 to about 22 carbon atoms and x is an integer having an average value of from about 6 to about 15.
The step of reacting the glycidyl ether with the ethoxylated alcohol is preferably conducted at a temperature of from about 95° C. to about 140° C. with 110° C. to 130° C. even more preferred when alkali metal alkoxylates are employed.
The step of providing the glycidyl ether may further comprises the step of reacting a linear aliphatic or aromatic alcohol having the formula R
2
OH and an epoxide having the formula:
wherein R
2
is defined as above and X is a leaving group. This reaction may also be conducted in the presence of a catalyst as defined above. The catalyst is typically employed at levels about 0.1 mol % to about 2.0 mol % and the reaction is preferably conducted in the absence of a solvent at temperatures of from about 40° C. to about 90° C.
As already noted, the surfactants have advantages, including superior spotting and filming reduction benefits as well as excellent greasy soil removal, good dishcare, suds suppression and good overall cleaning.
Accordingly, it is an aspect of the present invention to provide a process for producing a low-foaming nonionic surfactant having superior spotting and filming reduction benefits as well as excellent greasy soil removal, good dishcare, suds suppression and good overall cleaning. It is a further aspect of the present invention to provide a process for producing an ether-capped poly(oxyalkylated) alcohol surfactant. It is a further aspect of the present invention to provide a low-foaming nonionic surfactant produced by the process of the present invention. These and other aspects, features and advantages will be apparent from the following description and the appended claims.
In the description of the invention various embodiments and/or individual features are disclosed. As will be apparent for the skilled practitioner all combi
Back Deborah Jean
Formyduval Terry Franklin
Jordan, IV Glenn Thomas
Kluesener Bernard William
Levengood Donald Eugene
Barts Samuel
Cook C. Brant
Price Elvis O.
The Procter & Gamble & Company
Waugh Kevin L.
LandOfFree
Process for preparing ether-capped poly(oxyalkylated)... 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 for preparing ether-capped poly(oxyalkylated)..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for preparing ether-capped poly(oxyalkylated)... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2923552