Organic compounds -- part of the class 532-570 series – Organic compounds – Fatty compounds having an acid moiety which contains the...
Reexamination Certificate
1998-07-23
2001-08-14
Bell, Mark L. (Department: 1755)
Organic compounds -- part of the class 532-570 series
Organic compounds
Fatty compounds having an acid moiety which contains the...
C502S159000
Reexamination Certificate
active
06274749
ABSTRACT:
DESCRIPTION OF THE FIGURES.
In the following Description reference will be made to the accompanying drawing, wherein,
FIG. 1
is a bar chart showing the absolute exchange capacities of the listed resins; and
FIG. 2
is a bar chart showing the normalized exchange capacities of the listed resins measured before and after an esterification reaction.
High-temperature resistant sulfonated aromatic polyether ketone cation exchangers and sulfonated poly(phenylene sulfide) cation exchangers as catalysts at reaction temperatures above 150° C.
Acidic cation exchangers which are distinguished by a very high heat stability have been prepared on the basis of aromatic polyether ketones and poly(phenylene sulfide)s according to EP 0 575 807 A1, EP 0 574 791 A2, DE 195 10 026 A1 and DE 195 27 435.0 which is expressly incorporated herein by reference. Temperatures up to 240° C. are permissible as a long-term load, peak temperatures up to 280° C. are possible as a short-term load. The extremely high heat stability results from the use of the above-described starting materials and the special preparation process. Acidic cation exchange resins offered on the market are principally prepared on the basis of crosslinked styrene-divinylbenzene or acrylic and have a maximum working temperature of 150° C. They are usually used as proton-conducting membranes, for example in fuel cells. WO 97/19480 A1 and EP 0 574 791 A2 further disclose catalysts which comprise aromatic polyether ketones, but not as catalytically active materials.
It has now surprisingly been found that sulfonated aromatic polyether ketone cation exchangers and sulfonated poly(phenylene sulfide) cation exchangers may be used in a technical field other than that mentioned, that is to say as catalysts in heterogeneously acid-catalyzed reactions. This is all the more surprising, since to date there have been no acidic ion exchangers based on organic monomers.
The invention therefore relates to the use of sulfonated aromatic polyether ketone cation exchangers and sulfonated poly(phenylene sulfide) cation exchangers as catalysts.
In contrast to homogeneously catalyzed reactions, in the case of heterogeneously catalyzed reactions, the site of the reaction can be precisely defined and, furthermore, the removal, work-up and recycling of the catalyst is not required. On account of physicochemical or economic reasons, in the case of numerous heterogeneously catalyzed reactions, furthermore, a high working temperature is fundamentally necessary or at least highly advantageous. It is generally known that chemical reactions are accelerated, or are made possible at all, by high temperatures. Typical examples of such reactions are esterifications/ester cleavage, etherifications/ether cleavage, acetylization/acetal cleavage, eliminations/hydratization, and alkylations. In all these acid-catalyzed processes, said high-temperature resistant ion exchangers can be used advantageously. This is independent of the type of apparatus, which can be designed as a kettle reactor, tubular reactor, etc. A further surprising advantage of acidic cation exchangers based on aromatic polyether ketones and poly(phenylene sulfide)s results, that owing to the possible adjustment of the degree of ion exchanger equivalents, reactions at high temperatures can be selectively accelerated: thus in carboxylic acid/alcohol mixtures at high temperatures at low sulfonation degrees the esterification is preferentially catalyzed, and at higher sulfonation degrees the etherification of the alcohols present is preferentially catalyzed. Furthermore, the high-temperature resistant cation exchangers can be used in processes, such as reactive distillation, in which mass transfer of the individual product proceeds simultaneously with the reaction. In this case also, marked advantages of high-temperature resistant cation exchangers are demonstrated, since temperatures above 150° C. are frequently required precisely in the combined mass transfer by rectification.
The cation exchangers for the use according to the invention can be prepared in the following manner: the aromatic polymer is dissolved in 94-97% by weight sulfuric acid and the solution is admixed with a sulfonating agent, e.g. oleum, until the sulfuric acid concentration is 98-99.9% by weight. When the desired degree of sulfonation is achieved, the reaction batch is worked up. Poly(phenylene sulfide) is sulfonated in a mixture of oleum and chlorosulfonic acid. Up to ion exchanger equivalents of 1.0 mmol of SO
3
H/g, the materials are produced as powders insoluble in NMP (N-methyl-2-pyrrolidone). From ion-exchanger equivalents of 1.0 mmol of SO
3
H/g, the polymers are soluble in NMP or DMSO (dimethyl sulfoxide). If the degree of sulfonation is increased further, the polarity of the polymer increases, and from an ion-exchanger equivalent of 1.8 mmol of SO
3
H/g, the material is water-soluble.
These high-temperature resistant ion exchangers show, as derivatives of high-performance polymers, outstandingly high chemical and thermal resistance. According to DSC and TGA studies, at heating rates of 10° C./min, thermal desulfonation cannot be observed until above 300° C.
REFERENCES:
patent: 3553238 (1971-01-01), Cenker
patent: 4125549 (1978-11-01), Coopersmith et al.
patent: 4548754 (1985-10-01), Day et al.
patent: 4652406 (1987-03-01), Lepper et al.
patent: 5362836 (1994-11-01), Helmer-Metzmann et al.
patent: 5371253 (1994-12-01), Cooper
patent: 5426199 (1995-06-01), Lundquist
patent: 5438082 (1995-08-01), Helmer-Metzmann et al.
patent: 5536856 (1996-07-01), Harrison et al.
patent: 6096856 (2000-08-01), Helmer-Metzmann et al.
patent: 40 27 639 (1992-03-01), None
patent: 195 10 026 (1996-09-01), None
patent: 195 27 435 (1997-01-01), None
patent: 0 575 807 (1993-12-01), None
patent: 0574791 (1993-12-01), None
patent: WO 96/13073 (1996-05-01), None
patent: WO 96/29360 (1996-09-01), None
patent: WO 97/19480 (1997-05-01), None
T.R.E. Kressman, Chemistry and Industry, pp. 64-69, Jan. 1956.*
Ullmann's Encyclopedia of Industrial Chemistry, 6th ed., High-Temperature Polymers—Introduction; Polyaryletherketones; Poly(phenylene sulfide), 2000.*
Y. Z. Yuan et al., Chinese Chemical Letters, vol. 4, No. 2, pp. 163-166, 1993.
Bauer Wolfgang
Bönsel Harald
Daiminger Ulrich
Semel Joachim
Sievers Werner
Bell Mark L.
Frommer & Lawrence & Haug LLP
Hoechst Research & Technology GmbH & Co. KG
Pasterczyk J.
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