Organic fillers for elastomers

{
  "publication_number": "US4258146A",
  "country": "US",
  "kind": "A",
  "title": "Organic fillers for elastomers",
  "abstract": "Organic prepolymer fillers capable of curing and reacting chemically with elastomers to form covalent bonds therewith are mixed with elastomers to form reinforcing domains with diameters of from 0.01 to about 50 microns, and when the mixture is cured, the mechanical strength of the elastomer is increased. In many cases, the thermal stability and/or the hydrolytic stability will also be increased.",
  "claims": [
    "1. A process for increasing the mechanical strength of an elastomer, said process comprising the steps of: (1) forming a mixture of a silicone rubber elastomer containing reactive functionality with from about 1% to about 40% by weight of an organic prepolymer filler which contains functionality to react with said elastomer, (2) separating said filler into a separate phase of reinforcing domains having diameters of from 0.01 to about 50 microns dispersed throughout said elastomer, (3) curing the mixture to advance the molecular weight of the prepolymer filler and to bond it by covalent bonds to the elastomer.",
    "2. A process as claimed in claim 1 in which the prepolymer filler is a low molecular weight polyimide.",
    "3. A process as claimed in claim 1 wherein the prepolymer filler is a polydiacetylene prepolymer having a molecular weight of about 800.",
    "4. A process as claimed in claim 1 wherein the mixing is accomplished by dissolving the elastomer and the prepolymer filler in a mutual solvent.",
    "5. A process as claimed in claim 1 wherein the prepolymer filler having a particle size of from 0.01 to 50 microns in diameter, is physically mixed with the elastomer.",
    "6. A process as claimed in claim 1 wherein the curing is accomplished by heating.",
    "7. A process as claimed in claim 1 wherein the curing is accomplished by light.",
    "8. A process as claimed in claim 1 wherein the curing is accomplished by chemical means."
  ],
  "description_excerpt": "The present invention is concerned with a process for treating elastomers by adding organic prepolymer fillers thereto. In particular, the present invention provides a process for improving the mechanical strength of the elastomer. In many cases, the thermal stability or hydrolytic stability will also be increased. Improvement of such properties is the chief object of the present invention.\n\nMany elastomeric materials are mechanically very weak. In the past fillers have been added in an attempt to increase the mechanical strength of elastomers. The art is replete with the addition of inorganic fillers to elastomers. Such inorganic fillers are obviously distinguished from the organic prepolymer fillers of the present invention. Although inorganic fillers such as colloidal silica can improve mechanical properties of elastomers, they have the disadvantage of catalyzing decomposition of the resins at high temperatures.\n\nU.S. Pat. No. 3,627,836 teaches the use of grafting monomers which have been generated in situ. This grafting, of course, is distinguished from the present invention in that the reference does not show the use of a filler. Furthermore, unlike the present invention, separate phases are not formed.\n\nU.S. Pat. No. 3,962,519 shows a rubber material having an organic silicon compound incorporated therein. There is, however, no chemical bonding between the silicon compound and the rubber material.\n\nU.S. Pat. No. 4,014,851 teaches in situ polymerization of finely divided solid particles dispersed in a vinylorganopolysiloxane fluid.",
  "cpc": [
    "C08L 83/04",
    "C08G 77/04",
    "C08L 21/00"
  ],
  "ipc": [
    "C08G 73/00",
    "C08G 73/10",
    "C08L 21/00",
    "C08L 7/00",
    "C08L 83/00",
    "C08L 83/04"
  ],
  "assignees": [
    "International Business Machines Corp"
  ],
  "inventors": [
    "Richard D. Balanson",
    "James Economy",
    "Samuel J. Huang",
    "Thor L. Smith"
  ],
  "filing_date": "1979-09-28",
  "publication_date": "1981-03-24",
  "grant_date": "1981-03-24",
  "priority_date": "1979-09-28",
  "application_number": "US-7966079-A",
  "family_id": "22151985",
  "cited_by_count": 13,
  "citations": [
    "US2838469A",
    "US3962519A",
    "US3627836A",
    "US3989768A",
    "US3736290A",
    "US4014851A",
    "US4042441A"
  ]
}