Graft polymerization as a capsule wall treating process

Abstract

Abstract A PROCESS IS PROVIDED FOR TREATING, EN MASSE, EXISTING CAPSULE WALLS OF HYDROPHILIC POLYMERIC MATERIAL, IN A LIQUID MANUFACTURING VEHICLE, TO SEAL THE CAPSULE WALLS AGAINST LOSS OF FLUID MATERIALS THROUGH PERMEATION PATHWAYS. THE PROCESS INCLUDES REACTING MATERIAL OF THE CAPSULE WALLS WITH CERTAIN TRANSITION METALS TO PROVIDE NUCLEATION SITES UNLESS SUCH SITES ARE ALREADY PRESENT AND THEN INITIATING A FREE-RADICAL-GENERATED POLYMERIZATION REACTION WHEREIN POLYMERIC MATERIAL IS CREATED INTERSITIALLY OR INTERNALLY WITHIN THE WALL MATERIAL DURING WHICH IT BECOMES GRAFTED ONTO MOLECULAR UNITS OF THE CAPSULE WALL MATERIAL. CAPSULES RESULTING FROM PRACTICE OF THIS INVENTION HAVE WALLS WHICH EXHIBIT GREATLY DECREASED PERMEATION OF FLUIDS WHEN COMPARED WITH UNTREATED CAPSULE WALLS OF LIKE MATERIAL. EXAMPLES OF MATERIALS TO BE USED FOR THE GRAFT-POLYMERIZATION OF FREE-RADICAL-GENERATED POLYMERIC MATERIAL INCLUDE ACRYLONITRILE, METHACRYLONITRILE, FUMARONITRILE, AND ITACONONITRILE.

Inventors

• 👤 Donald Day Emrick

Bibliographic Details