Method of making polymeric polymers

• US 20030176570A1
• Filed: 03/12/2002
• Published: 09/18/2003
• Est. Priority Date: 03/12/2002
• Status: Abandoned Application

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Hagemeier, Larry D., Bennett, James R., Smith, Dennis E.
• Application Number:
  US10/095,389
• Publication Number:
  US 20030176570A1
• Time in Patent Office: Days
• US Class Current: 524/804
• CPC Class Codes: C08F 2/20 with the aid of macromolecular dispersing agents
• CPC Class Codes: C08F 2/44 Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
• CPC Class Codes: C08F 212/08 Styrene
• CPC Class Codes: C08F 212/36 Divinylbenzene

Abstract

A method of preventing the agglomeration of particles surrounded by a particulate suspension stabilizing agent which comprises providing an aqueous suspension of particles surrounded by a particulate suspension stabilizing agent and adding to the aqueous medium a polyanion.

Claims

1. A limited coalescence method for preparing polymer particles comprising the steps of:

a) providing an aqueous medium suspension of ethylenically unsaturated monomers having a layer of solid particulate suspension stabilizing agent coated on the surfaces of said monomers;

b) polymerizing said monomers to form a polymer; and

c) adding to the aqueous medium a polyanion selected from the group consisting of a polyacrylate according to Formula I,

where R═

H, CH₃;

n<

100,000; and

Y═

OH, OCH₃, O—

Na+

and a polymaleate according to formula (II) where n<

100,000 and Y═

OH, O⁻

Na+

2. The method of claim 1 wherein the polyanion is present in an amount of from 0.05 to 10% of the weight of the particles.

3. The method of claim 2 wherein the polyanion is present in an amount of from 1 to 5% of the weight of the particles.

4. The method of claim 1 wherein the polymer is washed.

5. The method of claim 1 wherein the polymer is dried after adding the polyanion.

6. The method of claim 1 wherein the ethylenically unsaturated monomer is styrene, methylmethacrylate, divinylbenzene or mixtures thereof.

7. The method of claim 1 wherein the particulate suspension stabilizing agent is colloidal silica.

8. The method of claim 1 wherein step 3 is performed before step c.

9. The method of claim 1 wherein step c is performed after step b.