United States Patent [19]
Barreto et al.[11]
[45]
Patent Number:Date of Patent:
5,324,752Jun. 28, 1994
[54] ION-EXCHANGE COMPOSITIONEMPLOYING RESIN A'ITACHMENT TODISPERSANT AND METHOD FORFORMING THE SAME
[75] Inventors: Victor B. Barreto, Santa Clara;Stephen Shawn Heberling,Mountain View; Vernon E.Summerfelt; Christopher A.Pohl, both of Union City, all of Calif.
[7g] Assignee: Dionex Corporation, Sunnyvale,Calif.
[21] App1. No.: 518,293
[22] Filed: May3,1990
Related U.s. Application Data
[63) Continuation of Ser. No. 315,506, Feb. 27, 1989,abandoned.
[51][52]
[58]
Int. CI' COSJ 5/20U.S. Cl. 521128; 521130;
521131Field of Search 521128, 30, 31
[56] References Cited
U.S. PATENT DOCUMENTS
4,101,4604,376,0474,447,5594,511,677
7/1978 Smalletal. 5211283/1983 Pohl 5211285/1984 Hanaoka et a1. 521128411985 Horton et al. 521128
4,804,6864,920,1524,927,539
2119894119905/1990
Regnier et al. 521128Regnier et al. 521128Stevens et a1. 521128
FOREIGN PATENT DOCUMENTS
62-204853 9/1987 Japan.
Primary Examiner-Thurman K. PageAssistant Examiner-P. KulkoskyAttorney, Agent, or Firm-Flehr, Hohbach, Test,Albritton & Herbert
[57] ABSTRACT
In accordance with the present invention, an ion-ex-change composition has been formed which comprisessynthetic resin support particles, dispersant capable ofsuspending the support particles in an aqueous medium toinhibit or prevent agglomeration, and fine synthetic resinlayering particles. In a preferred embodiment, the com-plex can be formed by contacting a suitable dispersantwith monomer in an aqueous solution in which the mono-mer is insoluble. Under suitable conditions for suspensionpolymerization, the monomer will polymerize to formresin support particles having dispersant irreversiblyattached to those particles. The dispersant is irreversiblyattached to the synthetic resin support particles, either bycovalent bonding or permanent physical entanglement.The dispersant is also attached to the fine layering par-ticles, either by covalent bonding or electrostatic forces.The result is formation of a support particle-dispersant-layering particle complex.
12 Claims, No Drawings
IIDIONEX Presented to
Steven Shaum. !J-(e6erCing