WO1997018265A1 - Procede de reglage de la concentration superficielle d'un additif pour polymere - Google Patents

Procede de reglage de la concentration superficielle d'un additif pour polymere Download PDF

Info

Publication number
WO1997018265A1
WO1997018265A1 PCT/US1996/018272 US9618272W WO9718265A1 WO 1997018265 A1 WO1997018265 A1 WO 1997018265A1 US 9618272 W US9618272 W US 9618272W WO 9718265 A1 WO9718265 A1 WO 9718265A1
Authority
WO
WIPO (PCT)
Prior art keywords
copolymer
concentration
base polymer
free energy
article
Prior art date
Application number
PCT/US1996/018272
Other languages
English (en)
Inventor
Lloyd Forrestal
Marc Voorhees
Original Assignee
Cobe Laboratories, Inc.
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 Cobe Laboratories, Inc. filed Critical Cobe Laboratories, Inc.
Priority to AU11592/97A priority Critical patent/AU1159297A/en
Publication of WO1997018265A1 publication Critical patent/WO1997018265A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • C08L67/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • 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
    • B29C33/00—Moulds or cores; Details thereof or accessories therefor
    • B29C33/38—Moulds or cores; Details thereof or accessories therefor characterised by the material or the manufacturing process
    • 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
    • B29C67/00—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00
    • B29C67/24—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 characterised by the choice of material
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L69/00—Compositions of polycarbonates; Compositions of derivatives of polycarbonates
    • 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
    • B29K2995/00—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds
    • B29K2995/0018—Properties of moulding materials, reinforcements, fillers, preformed parts or moulds having particular optical properties, e.g. fluorescent or phosphorescent
    • B29K2995/0026—Transparent

Definitions

  • the invention relates to polymeric materials and methods for improving their biocompatibility. More generally, the invention relates to controlling surface concentration of an additive within a polymeric matrix.
  • Biocompatibility is itself a multi-faceted problem which has different aspects depending on the type of device, what tissues or fluids it contacts, and the length of contact time.
  • the materials are in contact with blood flowing through tubing, into containers, and over membranes. The blood returns to the patient's body.
  • the primary elements of biocompatibility are therefore to prevent initiating processes which can subsequently injure the patient, such as activation of clotting mechanisms, activation of the complement system, and initiation of inflammatory reactions. Materials must not be soluble in blood or other body fluids to avoid being carried permanently into the patient's body.
  • U.S. Patent 4,872,867 discloses modifying a polyurethane with a water soluble polymer and crosslinking them i ⁇ situ with a silane type coupling agent to form a cross-linked and intertwined polysiloxane network.
  • U.S. 4,636,552 discloses a polydimethyl siloxane with polylactone side chains which are said to be useful for imparting biocompatibility when combined with a base polymer, or used to replace plasticizer.
  • Patent 4,929,510 discloses a diblock copolymer having a more hydrophobic block and a less hydrophobic block.
  • a solution of the diblock copolymer in a solvent which swells the matrix polymer is used to introduce the diblock into an article of matrix polymer. Thereafter, the article is transferred to water, to force orientation of the incorporated diblock copolymer such that the more hydrophobic block is embedded in the matrix and the less hydrophobic block is exposed on the surface of the article.
  • U.S. Patent 4,963,595 discloses block copolymers having polycaprolactone blocks and polysiloxane blocks useful as additives to modify a base polymer, such as nylon, and to modify the surface properties thereof.
  • Triblock copolymers having a polysiloxane block flanked by polycaprolactone blocks are commercially available, for example from Thoratec Laboratories, Berkeley, CA.
  • the abbreviation LSL is used herein to designate triblock copolymers of polylactone-polydimethylsiloxane-polylactone type, generally, and the abbreviation PDMS is used to designate the polydimethylsiloxane block, generally.
  • SMA siloxane dimethyl siloxane
  • lactone caprolactone
  • the nominal molecular weights of the caprolactone blocks range from about 1000 to about 10,000.
  • polysiloxane blocks of 1000 has been shown to be usable, as has a copolymer having polycaprolactone blocks of 10,000 and polysiloxane blocks of 5000 (SMA-4-10-5) .
  • U.S. Patent 3,686,355 disclosed that surface properties of wettability and surface friction could be reduced by addition of block copolymer additives of bisphenol-A and polydimethylsiloxane. It wa ⁇ noted that the effective concentration of the surface-active block copolymer additive at the surface of a shaped polymer composition appeared to depend on the nature of the substrate against which the shaping was carried out, for example by solvent casting or molding. It was believed that a high energy surface substrate material such as glass, mica, metals or metal oxides, adsorbed the copolymer additive from the base polymer surface in contact with it, resulting in loss of copolymer from the polymer surface after separation from the substrate surface. The surface effects of decreased wettability and friction provided by addition of the copolymer additive were therefore maximized by annealing the shaped article or by a solvent application to soften the surface to allow copolymer additive to pass to the surface of the article.
  • Polycarbonate is a very useful base polymer for medical devices intended for blood contact, for example blood oxygenators, heat exchangers and dialyzers used in heart surgery, transplant surgery, kidney dialysis and the like.
  • Polycarbonate is advantageous for such applications for a variety of reasons, notably for purposes of the invention herein, because it can be fabricated by molding to achieve complex shapes, and because the devices made of polycarbonate are essentially transparent. The latter is an important consideration for medical personnel using the devices, permitting them to see at a glance whether blood is flowing properly.
  • LSL triblock copolymers are attractive candidates for bulk additives to improve the biocompatibility of polycarbonate surfaces. A problem is encountered when a polycarbonate base polymer is molded with an LSL copolymer.
  • the invention provides methods and operating principles for controlling the concentration of LSL within a loA layer at the surface of the base polymer.
  • concentration of LSL measured as concentration of the polysiloxane block in the first loA of polymer surface can be varied from about 5% by weight to about 60% where bulk composition is only 0.2% LSL. No annealing is required.
  • the surface concentration ha ⁇ been found to be influenced by the interfacial surface free energy of the mold surface in contact with the base polymer-LSL blend during the molding process.
  • a polycarbonate base polymer retains its transparency. Adequate biocompatibility is found where surface concentration of PDMS is 20% (w/w) or greater.
  • the method of the invention makes it possible to achieve a biocompatible surface without sacrificing transparency.
  • a certain surface free energy is desired for a polymer blend having an additive with a different surface free energy than the base polymer
  • a wide range of additive surface concentrations can be achieved by appropriate choice of the mold surface free energy during fabrication.
  • Figure 1 is a 3-axis graph showing the effect of mold surface free energy on PDMS surface concentration, expressed as weight per cent. Samples were unannealed. Data from Table 1.
  • Figure 2 i ⁇ a 3-axi ⁇ bar graph showing the effect of annealing on duplicate samples to those shown in Figure 1. Data from Table 1.
  • Figure 3 is a 3-axis bar graph showing a comparison of annealed and unannealed duplicate samples molded against teflon. Data from Table 1.
  • Figure 4 is a 3-axis bar graph showing a comparison of annealed and unannealed duplicate samples molded against steel. Data from Table 1.
  • an LSL copolymer additive in a base polymer can be evaluated by measuring the concentration of the polysiloxane block, using X-ray photoelectron spectroscopy using an X-ray beam at a low take-off angle to the tested surface.
  • the method of the invention can be applied with a number of rigid bulk polymers such as Tenite, a cellulose-based polymer, rigid polyvinyl chloride polymers, polyolefins and polycarbonates.
  • a hydrophobic additive used to make the surface of a relatively hydrophilic polymer more hydrophobic
  • the process can also be used in the situation where a hydrophilic additive is used to render the surface of a hydrophobic base polymer more hydrophilic.
  • the base polymer and block copolymer additive can be blended or combined by any technique recognized in the art.
  • the base-additive mixture should be melted to a temperature sufficiently high to allow complete mixing and diffusion of mixture components, rather than mere surface fusion of polymer pellets.
  • 400°F-600°F. is suitable for use in the invention, with temperatures in the upper half of the range preferred. It will be understood that normal precaution ⁇ ⁇ hould be taken to avoid thermal decompo ⁇ ition, oxidation or other degradative proce ⁇ ses.
  • LSL additive In order to retain the normal transparency of polycarbonate, the bulk concentration of LSL additive should not exceed about 0.2% of LSL copolymer, by weight. The exact limit can vary slightly, depending on molecular weight and block length of each block. A preferred concentration is about 0.1%(w/w) of LSL copolymer.
  • Suitable additive LSL copolymers include the Thoratec "SMA" polymers having caprolactone blocks ranging from about 1000 to about 10,000 nominal molecular weight, and siloxane blocks ranging from about 1000 to about 5000 nominal molecular weight. Preferred additives have caprolactone blocks of about 2000 nominal M.W. and siloxane blocks of about 3000-5000 nominal M.W. , e.g SMA-423 and SMA-425.
  • Optimal operation of the invention depends upon intimate contact between the surfaces of the mold and of the polymer being molded. Mold surfaces should be made as smooth as practical. Cleanliness is important, to avoid contaminating mold surfaces with materials that could affect the surface free energy of the mold. Injection molding and compression molding are the preferred methods for forming articles made of LSL-blended polymers because pres ⁇ ure tend ⁇ to maximize the surface area of contact between polymer and mold surfaces.
  • the polycaprolactone blocks are considered to be buried in the base polymer to a depth greater than 10A, so that the surface concentrations determined by XPS reflect the surface concentration of PDMS but not of the entire triblock copolymer.
  • Various melt temperatures were tested. Duplicate samples were annealed sub ⁇ equently at 135°F. before mea ⁇ uring surface concentration. The results are shown graphically in figures 1-4, which are three-dimensional graphs of the surface concentration of additive copolymer (labeled as polydimethylsiloxane (PDMS) concentration, weight percent) as a function of melt temperature and time (mold surface contact time at the stated temperature) .
  • PDMS polydimethylsiloxane
  • Unannealed samples molded against teflon displayed ⁇ trikingly higher surface concentrations of additive ranging from 45%-59% w/w) of PDMS.
  • Annealed samples molded against steel displayed significantly increased surface concentrations of additive, 24%-47%(w/w) of PDMS compared to unannealed steel-molded samples.
  • annealed sample ⁇ molded again ⁇ t teflon displayed little, if any, change compared to unannealed, teflon-molded samples, 56%- 62%(w/w) of PDMS.
  • surface concentration was controlled over a 3-4 fold range, again without re ⁇ ort to annealing.
  • Even higher ⁇ urface concentration ⁇ and concentration ranges can be achieved by optimization of molding conditions, including time, temperature, mold surface treatment, contact-enhancing additive ⁇ , micro-enlargement of contact surface area and the like.
  • surface concentration of a low surface free energy additive blended into a higher surface free energy base polymer can be increased by molding the blend against a surface having low surface free energy, and decreased by molding against a surface having high surface free energy.
  • Application of the foregoing principle of the invention has the potential for achieving subtle variations of surface properties of a polymer blend. Such variations can be effected within area domains on the same surface. Since annealing is unnecessary, fine structural features can be incorporated on the polymer surface without being degraded by subsequent annealing. It is also evident to those skilled in the art that the principles of the invention apply in reverse.
  • a low ⁇ urface free energy ba ⁇ e polymer can be ⁇ urface-modified by blending a higher ⁇ urface free energy additive therewith and molding the blend in contact with a high surface free energy mold to maximize surface concentration of the additive and increase the surface free energy of the blend.
  • EXAMPLE 1 Samples of polycarbonate 2508 [Bayer] were blended with SMA-423 (samples 1-8) or SMA-425 (sample ⁇ 9- 16) to a bulk concentration of 0.2%(w/w) by using a compounding extruder. Samples were heated to the indicated temperature, then pressed between sheets of the indicated material for the indicated time to form small tiles of molded polymer. Surface concentration of additive was measured by low angle (10°) X-ray photoelectron spectroscopy. The analytical results were expressed as weight percent PDMS, as described, supra. The results are tabulated below and represented graphically in figs. 1-4.
  • test samples had a much higher contact angle
  • the ⁇ tripped gla ⁇ ⁇ urface of the te ⁇ t sample is 88% glass and only 12% polymer.
  • the analysis can be taken one step further. Assuming that the glass side surface is initially (when cast) as PDMS enriched as the air side and that the lower CA measured on the glass side of the test sample is the result of some of the enriched SMA being transferred from the surface during demolding, then, knowing the surface fraction of the material transferred from the glass ⁇ ide it is pos ⁇ ible to e ⁇ timate the expected CA of the glass side surface of the test sample.
  • ⁇ c Expected CA of the glass side surface
  • ⁇ i CA of unenriched glass side sample, i.e., glass side CA of control
  • ⁇ 2 CA of SMA enriched surface, i.e., air side CA of test sample
  • f 1 surface fraction tran ⁇ ferred material
  • 0.12 f surface fraction of material not transferred

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials For Medical Uses (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

La présente invention concerne un procédé de modification de la tension superficielle d'un mélange polymère dans lequel un polymère de base contient un additif dont la tension superficielle est différente de celle du polymère de base, et ce, sur une large plage de concentrations superficielles d'additif. Le procédé consiste à utiliser, pendant la fabrication, une surface de moulage présentant une tension superficielle adéquate. Ce procédé permet d'atteindre une concentration superficielle élevée de l'additif pour une faible concentration de masse, donnant ainsi une meilleure biocompatibilité sans perte de limpidité optique.
PCT/US1996/018272 1995-11-15 1996-11-13 Procede de reglage de la concentration superficielle d'un additif pour polymere WO1997018265A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU11592/97A AU1159297A (en) 1995-11-15 1996-11-13 Method for controlling surface concentration of a polymer additive

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US55832195A 1995-11-15 1995-11-15
US676495P 1995-11-15 1995-11-15
US60/006,764 1995-11-15
US08/558,321 1995-11-15

Publications (1)

Publication Number Publication Date
WO1997018265A1 true WO1997018265A1 (fr) 1997-05-22

Family

ID=26676028

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1996/018272 WO1997018265A1 (fr) 1995-11-15 1996-11-13 Procede de reglage de la concentration superficielle d'un additif pour polymere

Country Status (2)

Country Link
AU (1) AU1159297A (fr)
WO (1) WO1997018265A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006010717A2 (fr) * 2004-07-23 2006-02-02 Degussa Ag Matiere moulable de polyester, pouvant etre directement metallisee
US7642315B2 (en) 2007-06-15 2010-01-05 Sabic Innovative Plastics Ip B.V. Polycarbonate-poly(alkylene oxide) copolymer compositions and articles formed therefrom
US7649073B2 (en) 2007-06-15 2010-01-19 Sabic Innovative Plastics Ip B.V. Polycarbonate-poly(alkylene oxide) copolymer compositions and articles formed therefrom

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3686355A (en) * 1970-05-08 1972-08-22 Gen Electric Shaped composition of polymer and surface modifying block copolymer additive and method
US4963595A (en) * 1985-01-04 1990-10-16 Thoratec Laboratories Corporation Polysiloxane-polylactone block copolymers
EP0571787A1 (fr) * 1992-05-23 1993-12-01 REHAU AG + Co Articles médicaux

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3686355A (en) * 1970-05-08 1972-08-22 Gen Electric Shaped composition of polymer and surface modifying block copolymer additive and method
US4963595A (en) * 1985-01-04 1990-10-16 Thoratec Laboratories Corporation Polysiloxane-polylactone block copolymers
EP0571787A1 (fr) * 1992-05-23 1993-12-01 REHAU AG + Co Articles médicaux

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006010717A2 (fr) * 2004-07-23 2006-02-02 Degussa Ag Matiere moulable de polyester, pouvant etre directement metallisee
WO2006010717A3 (fr) * 2004-07-23 2006-03-23 Degussa Matiere moulable de polyester, pouvant etre directement metallisee
US7642315B2 (en) 2007-06-15 2010-01-05 Sabic Innovative Plastics Ip B.V. Polycarbonate-poly(alkylene oxide) copolymer compositions and articles formed therefrom
US7649073B2 (en) 2007-06-15 2010-01-19 Sabic Innovative Plastics Ip B.V. Polycarbonate-poly(alkylene oxide) copolymer compositions and articles formed therefrom

Also Published As

Publication number Publication date
AU1159297A (en) 1997-06-05

Similar Documents

Publication Publication Date Title
CA2347303C (fr) Article de plastique ayant subi un traitement de surface et methode de traitement de surface
JP4406713B2 (ja) 親水性表面を有するポリマー膜及びポリマー物品とその作製方法
AU624812B2 (en) Process for coating polymer surfaces and coated products produced using such process
KR100988152B1 (ko) 유체 반발성 미공성 재료
EP1141059B1 (fr) Copolymeres blocs fortement ramifies
US9328209B2 (en) Shape memory elastomeric composites and method of manufacturing
GB2140444A (en) Block polymer of poly(alkylsiloxane) hard block polymer and polyethylene oxide polymer
JPS6030711B2 (ja) 強化弗素樹脂
EP0629662B1 (fr) Composition de résine biodégradable, film poreux produit à partir de celle-ci et procédé pour sa fabrication
US5962563A (en) Method for controlling surface concentration of a polymer additive
Knauer et al. Enhanced surface properties of branched poly (ether sulfone) from semifluorinated polyhedral oligomeric silsequioxanes
WO1997018265A1 (fr) Procede de reglage de la concentration superficielle d'un additif pour polymere
Sakurada et al. Relation between the crystal structure of polymers and the elastic modulus of polymer crystals in the direction perpendicular to the chain axis
EP0288308A2 (fr) Préparation d'un récipient en poly(arylenesulfide) thermoformé
Hobbs et al. Diffusion bonding between BPA polycarbonate and poly (butylene terephthalate)
JPH09300892A (ja) 転写箔用ポリエステルフィルム
JPH0723450B2 (ja) 現場複合成形品製造用の重合体組成物
JP3986299B2 (ja) レーザー加工用プラスチック材料及び該材料が加工されたプラスチック光学素子
Grasel et al. Properties of extruded poly (tetramethylene oxide) Polyurethane block copolymers for blood-contacting applications
Aharoni Aromatic poly (ester carbonate)/poly-(ethylene terephthalate) alloys
Tanigami et al. Structural studies on ethylene‐tetrafluoroethylene copolymer: III. Deformation mechanism of row‐crystallized film
JP4312978B2 (ja) レーザー加工用プラスチック材料及び該材料が加工されたプラスチック構造体
EP2623287A1 (fr) Matière hautement polymère et son procédé de production
Sergeeva et al. Gradient interpenetrating polymer networks: formation and properties
Rofiqah et al. Poly (Vinyl Alcohol) Fiber Reinforced High Density Poly (Ethylene) Composites: Melting and Crystallization Behavior

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CA JP MX

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 97519076

Format of ref document f/p: F

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA