Epoxy-modified encapsulation composition

• US 5,128,086 A
• Filed: 08/15/1988
• Issued: 07/07/1992
• Est. Priority Date: 10/16/1985
• Status: Expired due to Fees

• Current Assignee: Uniroyal Chemical Company Inc
• Original Assignee: Uniroyal Chemical Company Inc
• Inventors: Tomko, Richard F., Sigworth, William D., Bae, Dong-Hak, Ranganathan, Revati
• Primary Examiner(s): Dawson, Robert A.
• Assistant Examiner(s): Kuhns, Allan R.
• Application Number:
  US07/232,420
• Time in Patent Office: 1,422 Days
• Field of Search: 264/279, 264/222.11, 264/272.13, 156/48
• US Class Current: 264/272.11
• CPC Class Codes: C08F 224/00 Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a heterocyclic ring containing oxygen cyclic esters of polyfunctional acids C08F218/00; cyclic anhydrides of unsaturated acids C08F220/00, C08F222/00
• CPC Class Codes: C08F 255/00 Macromolecular compounds obtained by polymerising monomers on to polymers of hydrocarbons as defined in group C08F10/00
• CPC Class Codes: C08F 279/02 on to polymers of conjugated dienes
• CPC Class Codes: G02B 6/443 Protective covering

Abstract

Epoxy-grafted, low molecular weight amorphous polymer compositions are employed in pourable, liquid telecommunication cable encapsulation compositions. Also disclosed is a method for encapsulating telecommunication cables as well as cables encapsulated with such an epoxy-grafted liquid encapsulant.

Claims

1. A method of encapsulating a telecommunication cable segment comprising the steps:

(A) placing a telecommunication cable segment within a closure;

(B) forming an encapsulation composition by mixing;

(1) a liquid graft polymer having a Brookfield viscosity of less than about 1,000,000 centipoise at 25°

C., said graft polymer either possessing no melting transition peak or a melting transition peak having a maximum value below 25°

C. as measured by Differential Scanning Calorimetry;

said graft polymer being comprised of;

a polymeric backbone selected from the group consisting of polyalphaolefin, ethylene/alphaolefin copolymer, ethylene/alphaolefin/nonconjugated polyene terpolymer, polyisoprene, polybutadiene, and a alphaolefin/polyene copolymers;

said polymeric backbone having grafted thereto a sufficient amount of at least one compound selected from the formulae;

##STR6## wherein R" is a C₂ -C₁₆ hydrocarbon radical containing an ethylenically unsaturated bond or a C₃ -C₁₂ radical containing one or more carbonyl groups and an ethylenically unsaturated double bond; and

R'"'"' is hydrogen or C₁ -C₄ alkyl;

such that said graft polymer is rendered crosslinkable;

said graft polymer having a number average molecular weight of between about 500 and about 20,000;

with

(2) a sufficient amount of a suitable curative to cure the composition;

(C) pouring a sufficient amount of said encapsulation composition into the closure such that the portion of said cable segment to be embedded is covered with said encapsulation composition; and

(D) subjecting said encapsulation composition to conditions sufficient to cure the composition.

2. The method of claim 1 wherein said graft polymer has a polymeric backbone selected from the group consisting of ethylene/alphaolefin copolymer, polyalphaolefin and ethylene/alphaolefine/nonconjugated polyene terpolymer.

3. The method of claim 2 wherein said graft polymer has a polymeric backbone selected from the group consisting of ethylene/propylene copolymer and ethylene/propylene/nonconjugated diene terpolymer.

4. The method of claim 3 wherein R" is a C₂ -C₁₂ hydrocarbon radical containing an ethylenically unsaturated bond or is an acrylate or a methacrylate radical.

5. The method of claim 2 wherein said polymeric backbone has grafted thereto allyl glycidyl ether.

6. The method of claim 2 wherein said graft copolymer has a number average molecular weight of between about 1,000 and about 4,500.

7. The method of claim 1 wherein said graft polymer has a number average molecular weight of between about 750 and about 10,000.

8. The method of claim 1 wherein said graft polymer has a Brookfield viscosity of less than about 500,000 centipoise at 25°

C.

9. The method of claim 1 wherein the curing conditions in step (D) comprise ambient pressure and temperature.