Polymeric feed-thru for chronic implantable devices

Patent metadata

Field	Value
Publication number	US-2016008607-A1
Application number	US-201514790238-A
Country	US
Kind code	A1
Filing date	Jul 2, 2015
Priority date	Jul 11, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

A method of making a feed-thru connector assembly includes inserting a conductor within an opening within a housing of a pulse generator and dispensing a sealant in a gap between the conductor and portions of the housing adjacent to the conductor that define the opening of the housing and curing the sealant to form a seal comprising a polyisobutylene cross-linked network.

First claim

We claim:

1 . An implantable system comprising:
a pulse generator including a housing, electronics within the housing, and an opening; a lead attached to the pulse generator; a feed-thru connector assembly mounted on the pulse generator and positioned at least partially within the opening, the feed-thru connector assembly comprising:
a conductor; and
a seal disposed within a gap between the conductor and portions of the housing adjacent to the conductor that define the opening of the housing, wherein the seal comprises a polyisobutylene cross-linked network.

2 . The implantable system of claim 1 , wherein the conductor comprises one of titanium, platinum iridium (PtIr), palladium iridium (PdIr), stainless steel SS316, MP35N, silver and gold alloys, and mixtures thereof.

3 . The implantable system of claim 1 , wherein at least a portion of a surface of the conductor includes a roughened surface.

4 . The implantable system of claim 1 , wherein the tensile strength between the conductor and the seal is greater than 1,500 psi.

5 . The implantable system of claim 1 , wherein the seal has a leak test rate less than about 4×10 −9 atm cc/sec (or Pa m 3 /s) when subjected to helium gas at a pressure of about 0.4 Pa.

6 . The implantable system of claim 1 , wherein the dielectric strength of the seal is greater than 1000 volts per mil.

7 . The implantable system of claim 1 , wherein the bulk resistivity of the seal is greater than 1×10 7 ohm-m.

8 . The implantable system of claim 1 , wherein the surface resistivity of the seal is greater than 1×10 6 ohm-m.

9 . A feed-thru connector assembly positioned at least partially within an opening in a pulse generator housing, the feed-thru connector assembly comprising:
a conductor disposed within the opening of the pulse generator housing; and a seal disposed within a gap between the conductor and portions of the pulse generator housing adjacent to the conductor, wherein the seal comprises a polyisobutylene cross-linked network.

10 . The feed-thru connector assembly of claim 9 , wherein the seal has a leak test rate less than about 4×10 −9 atm cc/sec (or Pa m 3 /s) when subjected to helium gas at a pressure of about 0.4 Pa.

11 . A method of making a feed-thru connector assembly for a pulse generator, the method comprising:
inserting a conductor within an opening within a housing of the pulse generator, the conductor being coupled to electronics housed within the housing; dispensing a sealant in a gap between the conductor and portions of the housing adjacent to the conductor that define the opening of the housing; and curing the sealant to form a seal comprising a polyisobutylene cross-linked network, wherein the seal is adapted to create a hermetic seal for the feedback assembly portion.

12 . The method of claim 11 , further comprising plasma treating at least a portion of the surface of the conductor that is bonded to the seal.

13 . The method of claim 11 , further comprising priming at least a portion of the conductor with a primer comprising an epoxy functional silane or a methylene diphenyl diisocyanate (MDI).

14 . The method of claim 11 , further comprising forming the polyisobutylene cross-linked network that comprises:
reacting a telechelic polyisobutylene diol and a diisocyanate to form a diisocyanate derivative; and reacting the diisocyanate derivative with a crosslinking initiator to form the polyisobutylene cross-linked network.

15 . The method of claim 11 , wherein the diisocyanate is 4,4′-methylenephenyl diisocyanate (MDI) and the crosslinking initiator is pentaerythritol.

16 . The method of claim 11 , further comprising forming the polyisobutylene cross-linked network that comprises:
reacting a diisocyanate with a polyol or a polyamine to form a polyisocyanate; and reacting the polyisocyanate with a telechelic polyisobutylene diol to form the polyisobutylene cross-linked network.

17 . The method of claim 16 , wherein the diisocyanate comprises 4,4′-methylenephenyl diisocyanate (MDI) and the polyol comprises 1,1,2,2-Tetrakis(p-hydroxyphenyl)ethane.

18 . The method of claim 11 , further comprising forming a polyisobutylene cross-linked network by reacting together:
a telechelic polyisobutylene derivative; a silane agent; and a transition metal species.

19 . The method of claim 18 , wherein the telechelic polyisobutylene derivative is a polyisobutylene dichloride or a polyisobutylene diallyl.

20 . The method of claim 18 , wherein the silane agent has more than two reactive hydrosilane groups per molecule in the presence of a catalyst.

Assignees

• Cardiac Pacemakers Inc

Inventors

• Kane Michael J
• Delaney Jr Joseph Thomas
• Seethamraju Kasyap

Classifications

• H01B3/28

  natural or synthetic rubbers · CPC title

• H01B3/441

  from alkenes · CPC title

• A61N1/362

  Heart stimulators (heart defibrillators A61N1/39) · CPC title

• A61N1/3754 Primary

  Feedthroughs · CPC title

• B32B2581/00

  Seals; Sealing equipment; Gaskets · CPC title