Process of producing a composite macrostructure of organic and inorganic materials

• US 4,859,383 A
• Filed: 04/25/1988
• Issued: 08/22/1989
• Est. Priority Date: 06/01/1987
• Status: Expired due to Fees

• Current Assignee: Bio Med Sciences Incorporated (Uluru Inc.)
• Original Assignee: Bio Med Sciences Incorporated (Uluru Inc.)
• Inventors: Dillon, Mark E.
• Primary Examiner(s): Silbaugh, Jan H.
• Assistant Examiner(s): Kutach, Karen D.
• Application Number:
  US07/185,424
• Time in Patent Office: 484 Days
• Field of Search: 264/42, 264/43, 264/49, 264/127, 264/56, 264/60, 264/344, 264/233, 366/101, 366/106, 366/107
• US Class Current: 264/43
• CPC Class Codes: A61L 27/46 with phosphorus-containing inorganic fillers
• CPC Class Codes: C04B 26/32 containing silicon
• CPC Class Codes: C08J 2327/18 Homopolymers or copolymers of tetrafluoroethylene
• CPC Class Codes: C08J 9/26 by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: C08K 3/32 Phosphorus-containing compounds
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene
• CPC Class Codes: C08L 51/06 grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
• CPC Class Codes: C08L 83/04 Polysiloxanes

Abstract

A composite self-supporting flexible agglomerated macrostructure is described which includes (1) a matrix of unfibrillated polytetrafluoroethylene resin and addition curable silicone and (2) particulate material including hydroxyapatite and/or tricalcium phosphate uniformly distributed throughout said matrix, the macrostructure being uniformly permeated by a network of open pores formed in the process of manufacture by intimately blending particulate sodium chloride and subsequently leaching the sodium chloride particles.

Claims

1. A process of producing a composite macrostructure comprising the steps of first (1) intimately blending a mixture of a major amount of unsintered and unfibrillated particulate polytetrafluoroethylene resin and minor amounts of (A) a hydrocarbon liquid and (B) an addition curable silicone composition containing a crosslinking catalyst, then (2) intimately blending with the product of step (1) both a particulate ceramic material selected from the group consisting of hydroxyapatite and tricalcium phosphate and a particulate sodium chloride whose particle size is determined by a desired size of open pores in the macrostructure, then (3) introducing the product of step (2) into opposing streams of air within a mill so as to form a homogeneous particulate mixture, then (4) subjecting the product of step (3) to mechanical pressure within a die, then (5) hot pressing the product of step (4) at a temperature sufficient to sinter the polytetrafluoroethylene and to cure the silicone composition and then (6) solubilizing the particulate sodium chloride so as to create a network of open pores in the product of step (6) corresponding in size to the original sodium chloride particles.

2. The process of claim 1, wherein the pressure of step (4) is about 5,000 psi.

3. The process of claim 1, wherein the pressure of step (5) is 2,000 psi.

4. The process of claim 1, wherein the temperature of step (5) is 340°

C.