WO2003045666A1 - Procede de traitement de polymeres expansibles, et produits fabriques par ledit procede - Google Patents

Procede de traitement de polymeres expansibles, et produits fabriques par ledit procede Download PDF

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Publication number
WO2003045666A1
WO2003045666A1 PCT/US2001/043402 US0143402W WO03045666A1 WO 2003045666 A1 WO2003045666 A1 WO 2003045666A1 US 0143402 W US0143402 W US 0143402W WO 03045666 A1 WO03045666 A1 WO 03045666A1
Authority
WO
WIPO (PCT)
Prior art keywords
stretching
expandable polymer
wettable liquid
wetted material
wettable
Prior art date
Application number
PCT/US2001/043402
Other languages
English (en)
Inventor
Roger Labrecque
Joseph Ferraro
Tom Swanick
Paul Martakos
Original Assignee
Atrium Medical Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Atrium Medical Corporation filed Critical Atrium Medical Corporation
Priority to PCT/US2001/043402 priority Critical patent/WO2003045666A1/fr
Priority to AU2002225660A priority patent/AU2002225660A1/en
Publication of WO2003045666A1 publication Critical patent/WO2003045666A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
    • B29C55/005—Shaping by stretching, e.g. drawing through a die; Apparatus therefor characterised by the choice of materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07—Flat, e.g. panels
    • B29C48/08—Flat, e.g. panels flexible, e.g. films
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2027/00—Use of polyvinylhalogenides or derivatives thereof as moulding material
    • B29K2027/12—Use of polyvinylhalogenides or derivatives thereof as moulding material containing fluorine
    • B29K2027/18—PTFE, i.e. polytetrafluorethene, e.g. ePTFE, i.e. expanded polytetrafluorethene

Definitions

  • the present invention relates generally to materials and processing of materials.
  • the present invention is directed to expandable polymers and methods
  • a powdered resin is to blend a powdered resin with a wettable liquid, such as a lubricant or
  • a wettable liquid is mixed with the powdered resin to control the
  • the billet is extruded through a die having a desired
  • the dried extruded material is then stretched in one or
  • nodes characterized by elongated nodes interconnected by fibrils.
  • the nodes are
  • pre-sinter expansion often result in breaking or tearing of the film.
  • the present invention is directed generally to methods for treating expandable
  • the invention relates to
  • the steps of re wetting the expandable polymer with a wettable liquid to form a wetted material involving the steps of re wetting the expandable polymer with a wettable liquid to form a wetted material, and stretching the wetted material.
  • the wettable liquid is
  • an article is formed by rewetting an
  • Figure 1A illustrates an exemplary method of a first embodiment of the
  • Figure IB illustrates exemplary variations of a first embodiment of the invention
  • Figure 2 A illustrates an exemplary method of a second embodiment of the
  • Figure 2B illustrates exemplary variations of a second embodiment of the
  • Figure 3 provides a scanning electron micrograph (SEM) of Material A
  • Figure 4 provides an SEM of Material B
  • Figure 5 provides an SEM of Material D of the invention
  • Figure 6 provides an SEM of Material F
  • Figure 7 provides an SEM of Material G
  • Figure 8 provides an SEM of Material H of the invention
  • Figure 9 provides an SEM of Material I of the invention.
  • Figure 10 provides an SEM of Material J of the invention
  • Figure 11 provides an SEM of Material K of the invention
  • Figure 12 provides an SEM of Material L
  • Figure 13 provides an SEM of Material M
  • Figure 14 provides an SEM of Material N of the invention.
  • Figure 15 provides an SEM of Material O of the invention.
  • Figure 16 provides an SEM of an exterior of Sample P
  • Figure 17 provides an SEM of an interior of Sample P
  • Figure 18 provides an SEM of a cross-section of Sample P
  • Figure 19 provides an SEM of an exterior of Sample Q of the invention.
  • Figure 20 provides an SEM of an interior of Sample Q of the invention
  • Figure 21 provides an SEM of a cross-section of Sample Q of the invention
  • Figure 22 provides an SEM of an exterior of Sample R of the invention
  • Figure 23 provides an SEM of an interior of Sample R of the invention.
  • Figure 24 provides an SEM of a cross-section of Sample R of the invention
  • Figure 25 provides an SEM of an exterior of Sample S of the invention
  • Figure 26 provides an SEM of an interior of Sample S of the invention.
  • Figure 27 provides an SEM of a cross-section of Sample S of the invention
  • Figure 28 provides an SEM of Material X
  • Figure 29 provides an SEM of Material Y of the invention.
  • the present invention provides a means to expand expandable polymers at or
  • polyolefins are polymers suitable for expansion processes.
  • Fluoropolymers include
  • Polyolefins include
  • contact angle decreases so contact angle is a useful inverse measure of wettability.
  • Contact angle is the angle measured which the liquid makes with a solid. The contact
  • a porous material is said to be "wet" when the voids of
  • the material are at least partially occupied by a given fluid.
  • Rewetting involves the
  • This method is not limited to room temperature conditions and can be
  • PTFE can provide: modified processability, material structures which differ from those
  • the invention typically provides
  • the extrudate may also be sintered, after stretching or before stretching, by
  • the methods of the invention can simultaneously provide greatly reduced sintering times
  • the present invention does not disturb
  • expandable polymers has a wide variety of applications in medical, industrial, and
  • flat sheets, hollow tubes, and solid rods can be manufactured and utilized in
  • Expanded PTFE material is characterized by lengthwise-oriented fibrils
  • the pore size in microns is typically determined by
  • the material is viewed under sufficient magnification.
  • a fibril length is measured
  • Nodes and fibrils may be further characterized by their relative geometry. That
  • connecting nodes is composed of solid thread like PTFE fibers called fibrils in
  • Fibril density refers to the relative volume
  • Permeability or hydraulic conductivity is related to material porosity.
  • Permeability to fluid flow can be determined by measuring the amount of pressure
  • Water entry pressure is a measure of Water entry pressure
  • WEP is defined as the pressure value necessary to
  • Machine direction refers to the direction in which the polymeric material
  • Transverse direction refers to the direction
  • LTS Longitudinal Tensile Strength
  • RTS Radial Tensile Strength
  • RTS is obtained by dividing the radial expansion force applied to the
  • Cross-sectional area is the amount
  • SRT Suture Retention strength
  • Cylinders, tubes, sheets, or other shapes can be created by either of these
  • expandable polymer material may be prepared in a variety of ways, one method involves
  • a wettable liquid is capable
  • the invention is not limited to
  • expandable polymers prepared by extrusion, or by the use of a wettable liquid for
  • an expandable polymer resin such as PTFE resin (Fluon
  • CD- 123 obtained from ICI Americas, may be blended with a first wettable liquid, such
  • the wettable liquid may be mixed with the resin to control the degree of material shear that occurs during subsequent extrusion and to prevent excessive shear,
  • the lubricated powder may
  • the billet may be extruded through a die having a
  • An expandable polymer is rewet, step 110, with a second wettable liquid such as
  • Rewetting may be performed by exposing the expandable polymer to the
  • second wettable liquid such as by submerging or soaking the expandable polymer in the
  • elevated temperature or pressure above ambient conditions may be used in
  • Stretching, step 120, is then performed, preferably at a temperature below a
  • Stretching can be performed in more than
  • Stretching is typically performed, in the case of a cylinder, by applying
  • stretching may be any suitable technique. Alternatively, or in addition, stretching may be any suitable technique.
  • a mandrel may be used to radially stretch
  • Tensile force may be applied to stretch the cylinder
  • heat may also be applied to the
  • polyethylene glycol is preferred for in vivo applications because it is a biocompatible
  • Naphtha is another example of a wettable liquid that may be used within the
  • Alcohol and water may also be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also possible to be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination. It is also be used in combination.
  • step 130 include removing the second wettable liquid, step 130. Although removal can be
  • step 140 to, for
  • 320° C can be performed following removal of the second wettable liquid, step
  • Heating, step 140, may optionally be sufficient to cause sintering, typically at
  • step 150 sintering
  • step 130 after optional removing of the wettable liquid, step 130. As discussed above, this
  • second stretching step 160 may involve heating prior to or during stretching and may be
  • step 170 may optionally be performed after
  • a further variation of the first embodiment of the invention includes calendaring,
  • step 180 before the rewetting step 110. Calendaring is preferably performed during the
  • rolls are operated at an elevated temperature, such as, for example, 130° F.
  • second embodiment of the invention differs from the first embodiment, at least in part,
  • step 220 is preferable that stretching be performed with heat, for example in radiant heat oven set to approximately 705° F, thereby allowing greater stretch ratios.
  • a wettable liquid may
  • Stretching, step 230 is performed as discussed in relation to the stretching step
  • stretching discussed in relation to stretching step 120 of the first embodiment are also
  • pressure may be applied by the use of rollers
  • step 240 is optionally performed after the stretching step 230. Further optional
  • a third stretching step 260 may be performed after removal of the
  • a further variation of the second embodiment involves sintering, step 250, after
  • cooling, step 280 may be performed prior to the rewetting step 220. Cooling, step 290,
  • step 270 may also be performed after optional removal of the first wettable liquid, step 270.
  • stretching step 230 is not conducted.
  • stretching step 210 The step of stretching without heat or use of a wettable liquid
  • step 320 includes preliminary stretching of the expandable polymer, step 320, before the first
  • stretching step 210 Preliminary stretching, step 320, before the first stretching step 210
  • step 310 may be conducted prior to optional removal of the first wettable liquid, step 310, but the
  • a further variation of the second embodiment includes calendaring.
  • calendaring is typically performed during
  • the step of calendaring 330, 340 may be conducted shortly
  • stretching 310 the step of removal of the first wettable liquid 310, or stretching step 210.
  • Example 1 of the invention, Material D, involves flat material that is stretched in
  • example provides increased density of the material and an altered node structure from
  • ISOPAR-H odorless lubricant solvent produced by EXXON Corporation
  • the flat sheet was then compressed through two heated rolls to form a film having a thickness of 5 mil.
  • the lubricant was then removed from the film by passing
  • the film through a radiant heat oven set to 490°F to drive off the ISOPAR-H.
  • the film was then stretched in the machine direction at a ratio of 10:1 in a radiant
  • Material A is rewet with the ISOPAR-
  • Figure 5 shows the elongated nodes and alignment of
  • Figures 4 and 5 illustrate that by stretching the material wet, a substantially
  • Material D shown in Figure 5, the film formed by
  • Example 1 consists of densely
  • Example 2 of the invention involves a flat material that is stretched in the
  • Example 1 is compressed into a cylinder and ram extruded into a flat sheet 6 inches
  • Example 1 The ISOPAR-H is then driven off by passing the film through a radiant
  • Material F was made by stretching Material E in the transverse direction, with
  • Material F has a star-like structure.
  • Figure 6 shows a scanning electron micrograph (SEM) of Material F.
  • Material F has a very inconsistent
  • Material G was made like Material F, except that
  • Material E is wet with the ISOPAR-
  • Figure 8 is a scanning electron micrograph of
  • Material H has a node structure that has long drawn out nodes and very
  • material H is consistently 0.5 mils, and the density of Material H is 1.228 g/cm 3 , which
  • Material I shown in Figure 9, is material that started out as Material H.
  • Material J Another variation of the invention, Material J, involves increasing tension on the
  • take-up roller to stretch the material in the machine direction during stretching in the
  • Material J is very similar to Material H involving wetting Material
  • tension on the take up roller imparts some longitudinal orientation to the nodes.
  • Material J was slightly thicker than Material H, 0.63 mils vs. 0.5 mils, and slightly less dense, 1.158 g/cm 3 vs. 1.228 g/cm 3 . As shown in Figure 10, Material J has long wavy
  • Example 3 of the invention involves a flat material that is stretched in the
  • Example 1 is compressed into a cylinder and ram extruded into a flat sheet 6 inches
  • a first wettable liquid was then removed by passing the film through an oven. The film was then stretched in the
  • the thickness of the sample according to the invention was less than the control
  • dry processed material had a tendency to shrink and had noticeable striations in it.
  • the present invention is applicable to a wide variety of product configurations.
  • Example # 4 illustrate various embodiments of the invention involving tubes.
  • Example 4 involves longitudinal stretching of a tube according to the first
  • Example 5 involves stretching of tubes both radially and longitudinally according
  • a benefit of this example is a very thin
  • CD-123 is blended with ISOPAR-H odorless solvent at a level of 17% by weight.
  • lubricated powder is then compressed into a cylinder and ram extruded into a 2mm-
  • the ISOPAR-H is driven off in a convection oven at 250°F.
  • the tube is
  • the tube is then rewet with ISOPAR-H and stretched over a 19 mm mandrel.
  • ISOPAR-H is driven off in a convection oven at 250°F.
  • the tube is then sintered in a
  • the resulting tube, Material K shown in Figure 11 has a thickness of 0.5 mil and has an inner porosity of ⁇ 1 ⁇ m.
  • the density of Material K is
  • This example involves changing the node structure and density of an ePTFE tube
  • PTFE resin Fluon CD-123
  • ISOPAR-H odorless solvent is blended with ISOPAR-H odorless solvent at a level of
  • the lubricated powder is then compressed into a cylinder and ram
  • Material L shown in Figure 12, was formed by stretching from 15" -
  • Material M shown in Figure 13, was formed by
  • Material N shown in Figure 14, was formed in accordance with the second
  • Material O shown in Figure 15, was created in accordance with the first embodiment of
  • the invention by wetting with a wettable liquid, then stretching from 15" - 20" at room temperature. The wettable liquid was then removed and stretching with heat
  • Material O has a very tight internodal
  • a further example of the invention involves a tube comprised of layers with
  • Variation in porosity can allow enhanced blood flow through a
  • grafts prepared in a layered fashion consist of a highly stretched inner layer mounted on
  • a 6 mm mandrel that is wrapped with a tight porosity ePTFE film and covered with a high porosity outer layer.
  • the resulting tube has a smooth, silky feel with a 10 mil wall
  • Sample P shown in Figures 16-18, is an example of a vascular graft prepared
  • a highly stretched and sintered graft is placed onto a mandrel where it is
  • Figure 16 illustrates the
  • Figure 18 illustrates an interior surface.
  • Sample Q is a graft that is made with the same materials as Sample P, but the
  • sintered cover is prepared by stretching a second tube over a 10 mm mandrel.
  • Figure 19 shows an exterior of Sample Q
  • Figures 20 and 21 are interior and cross-sectional views of Sample Q, respectively.
  • Sample R is a graft that is constructed like Sample Q, except that the wrapped
  • ISOPAR-H is then run off with heat and the entire assembly is then sintered together.
  • Sample S is a graft that is made with a sintered inner layer that is radially
  • Samples Q ( Figure 20) and R ( Figure 23) have a
  • Another embodiment of the invention involves the use of a crusher, such as a
  • Samples T - W illustrate the
  • the present invention is applicable to a wide variety of product configurations.
  • Example 8 of the invention involves a flat material that has pressure applied to it
  • Example 1 The same lubricated powder of Example 1 is
  • a first wettable liquid was then removed by passing the
  • Material Y has a much higher fibril density than Material X and has a denser
  • Material Y was thinner than Material X, 1.2 mil and 3.1 mil
  • temperature and/or pressure may be applied during initial wetting or rewetting by the use of increased or decreased temperature and/or pressure.
  • Increased or decreased temperature and/or pressure can be applied during initial wetting or rewetting by the use of increased or decreased temperature and/or pressure.
  • the techniques of the present invention may be employed to create implantable
  • prosthetic devices that are adapted for delivery of bioactive materials. For example,
  • vascular grafts with multiple lumens may be created using the techniques described
  • Expandable polymers of the present invention have wide ranging applications
  • heart valves are not limited to heart valves, sutures, vascular access devices, vascular grafts, shunts
  • membranes containing regions of selective porosity and chemistry are useful in the
  • test strips contain multilayer membranes with selective binding sites in each layer to
  • expandable polymers may be any suitable polymers. According to additional aspects of the invention, expandable polymers may be any suitable polymers.
  • grafts grafts, prosthetic patches, vascular access devices, shunts, catheters, sutures or implantable tissue augmentation devices, such as those used in cosmetic surgery.
  • the articles of manufacture include single and
  • the invention can be applied to other processes where stretching or expanding of
  • implantable devices having tailored porosity and/or
  • any known methods for varying the porosity and/or chemistry for varying the porosity and/or chemistry
  • blended pasted viewed in combination with the disclosed methods are considered to be
  • Patent is:

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
  • Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)

Abstract

L'invention concerne des procédés consistant à remouiller des polymères expansibles avec un liquide mouillant, afin de permettre une meilleure expansion sans rupture, à température ambiante ou à une température inférieure à cette dernière, et, dans certains cas, d'atteindre un coefficient d'expansion supérieur à celui qui est obtenu à des températures élevées au moyen des procédés connus. La présente invention permet également d'obtenir un matériau présentant des propriétés et des caractéristiques de manipulation uniques. Lesdites propriétés comprennent une épaisseur matérielle moins importante, une densité plus élevée, une morphologie noeud/fibrille modifiée, et une bande plus régulière dans le cas d'un matériau plat. La mise en oeuvre de ce procédé n'est pas limitée aux conditions de température ambiante, et peut toujours être réalisée lorsque le polymère expansible est mouillé avec un liquide mouillant, l'expansion étant effectuée à une température de préférence inférieure aux points de vaporisation ou d'ébullition dudit liquide.
PCT/US2001/043402 2001-11-21 2001-11-21 Procede de traitement de polymeres expansibles, et produits fabriques par ledit procede WO2003045666A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/US2001/043402 WO2003045666A1 (fr) 2001-11-21 2001-11-21 Procede de traitement de polymeres expansibles, et produits fabriques par ledit procede
AU2002225660A AU2002225660A1 (en) 2001-11-21 2001-11-21 Method for treating expandable polymer materials and products produced therefrom

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2001/043402 WO2003045666A1 (fr) 2001-11-21 2001-11-21 Procede de traitement de polymeres expansibles, et produits fabriques par ledit procede

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WO2003045666A1 true WO2003045666A1 (fr) 2003-06-05

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016018967A1 (fr) * 2014-07-29 2016-02-04 W. L. Gore & Associates, Inc. Articles poreux formés à partir de poly(para-xylylène) et procédés de formation de ces derniers
KR20180104705A (ko) * 2016-01-27 2018-09-21 더블유.엘. 고어 앤드 어소시에이트스, 인코포레이티드 폴리파라크실릴렌으로 형성된 다공성 물품 및 이의 형성 방법

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JPS5486573A (en) * 1977-12-23 1979-07-10 Nitto Electric Ind Co Ltd Production of porous polytetrafluoroethylene article
EP0106496A2 (fr) * 1982-09-10 1984-04-25 W.L. Gore & Associates, Inc. Matériel poreux de polytétrafluoréthylène
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EP0288021A2 (fr) * 1987-04-24 1988-10-26 Ppg Industries, Inc. Matériau microporeux étiré
US5721283A (en) * 1992-06-25 1998-02-24 E. I. Du Pont De Nemours And Company Porous polytetrafluoroethylene and preparation
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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016018967A1 (fr) * 2014-07-29 2016-02-04 W. L. Gore & Associates, Inc. Articles poreux formés à partir de poly(para-xylylène) et procédés de formation de ces derniers
CN106795303A (zh) * 2014-07-29 2017-05-31 W.L.戈尔及同仁股份有限公司 由聚对二甲苯形成的多孔制品以及用于形成该制品的方法
EP3385346A1 (fr) * 2014-07-29 2018-10-10 W.L. Gore & Associates Inc. Articles poreux formés à partir de polyparaxylylène et procédés de formation associés
EP3388492A1 (fr) * 2014-07-29 2018-10-17 W. L. Gore & Associates Inc Articles poreux formés à partir de polyparaxylylène et leurs procédés de fabrication
CN106795303B (zh) * 2014-07-29 2020-12-25 W.L.戈尔及同仁股份有限公司 由聚对二甲苯形成的多孔制品以及用于形成该制品的方法
KR20180104705A (ko) * 2016-01-27 2018-09-21 더블유.엘. 고어 앤드 어소시에이트스, 인코포레이티드 폴리파라크실릴렌으로 형성된 다공성 물품 및 이의 형성 방법
JP2018538403A (ja) * 2016-01-27 2018-12-27 ダブリュ．エル．ゴア アンド アソシエイツ，インコーポレイティドＷ．Ｌ． Ｇｏｒｅ ＆ Ａｓｓｏｃｉａｔｅｓ， Ｉｎｃｏｒｐｏｒａｔｅｄ ポリパラキシレンから形成された多孔性物品及びその形成方法
KR102134982B1 (ko) 2016-01-27 2020-07-16 더블유.엘. 고어 앤드 어소시에이트스, 인코포레이티드 폴리파라크실릴렌으로 형성된 다공성 물품 및 이의 형성 방법

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