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EP0387348A1 - Composites de polymere-organobismuth homogenes et radio-opaques - Google Patents

Composites de polymere-organobismuth homogenes et radio-opaques

Info

Publication number
EP0387348A1
EP0387348A1 EP89911685A EP89911685A EP0387348A1 EP 0387348 A1 EP0387348 A1 EP 0387348A1 EP 89911685 A EP89911685 A EP 89911685A EP 89911685 A EP89911685 A EP 89911685A EP 0387348 A1 EP0387348 A1 EP 0387348A1
Authority
EP
European Patent Office
Prior art keywords
substituted phenyls
polymer
alkene
ester
group
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP89911685A
Other languages
German (de)
English (en)
Other versions
EP0387348A4 (en
Inventor
Johannes Smid
Yadollah Delaviz
Israel Cabasso
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Publication of EP0387348A1 publication Critical patent/EP0387348A1/fr
Publication of EP0387348A4 publication Critical patent/EP0387348A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/44—Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F1/00—Shielding characterised by the composition of the materials
    • G21F1/02—Selection of uniform shielding materials
    • G21F1/10—Organic substances; Dispersions in organic carriers
    • G21F1/103—Dispersions in organic carriers
    • G21F1/106—Dispersions in organic carriers metallic dispersions

Definitions

  • the present invention relates to new and useful
  • radiopaque polymers containing heavy metal salts have not bee totally satisfactory.
  • One type of known heavy metal-containing radiopaque materials are radiopaque glass containing embedded heavy metals. In these materials, the metal is not molecularly bou to the polymer matrix and, therefore, has a tendency to weake the composite.
  • glass filler based resins lack homogeneity a further weakening of regions in the matrix results. Those regions of a composite having little or no glass are radiolucent.
  • a light scattering effec is produced by radiopaque glasses which alters optical properties and renders them optically opaque. 1 Polymers with added inorganic heavy metal salts in an
  • Such composites require that the complexing polymer contain at least one monomer which is capable of
  • a further objective of this invention is to provide
  • radiopacifying or x-ray ⁇ contrast additive may also act as a bactericide, fungicide,
  • the heavy metal containing organic compound has
  • R 1; R and R 3 may be the same or
  • Heavy metals useful in this invention have atomic 1 numbers of 50 to 92, an more preferrably, atomic numbers of 7
  • the present invention are relatively non-polar and are thus
  • 27 bismuth include bactericide, fungicide, antioxidant and
  • the present invention provides
  • radiopaque materials which comprise a heavy metal containin
  • a heavy meta 2 containing organic compound such as an organobismuth compo
  • this invention provides radiopa
  • Rl, R , R3 substituents is a polymerizable group, such as,
  • the heavy metal radio-pacifying agent is non-leachable.
  • the polymer composite may be formed from any monome or mixture of monomers into which the selected organometallic compound can be solubilized. It may also be formed by castin a homogeneous mixture of the polymer and the radiopacifying agent from an appropriate solvent.
  • the method of imparting radiopaque characteristics of this invention has a much wider range of structures and applications than the heavy metal sal previously mentioned. The latter are essentially only useful with carbonyl-containing monomers and polymers, while the mor hydrophobic organobismuth and related compounds are soluble i a much wider range of monomers and polymers.
  • Useful polymers and mixtures of polymers include those derived from styrene, vinyl halides, alkenes, (e.g., polypropylene), dienes vinylpyridines, those derived from, acrylonitrile, vinyl acetate, acrylates and the like.
  • the organometallic compound can also be mixed, or incorporated into condensation polymers. They include linear and cross-linked types formed from dicarboxylic acids and dio or triols.
  • polyesters include polyethylene terephthalate, poly (isophthalic acid-co-maleic anhydride), poly (lauric acid-co-glycerol) , an the cross-linked resin poly (phthalic anhydride-co-glycerol) (glyptal) •
  • the polyester composite fibers of this invention are especially of interest for making fabrics for clothing to be worn by workers exposed to potentially harmful levels of radiation, such as radiologists and x-ray technicians.
  • the heavy metal containing organic compound should b present in an amount sufficient to impart a desired radiopaci to the polymer.
  • the relative amounts of the components of composites of this invention depend largely upon the speci heavy metal containing organic compound utilized, the speci polymer or mixture of polymers, the dimensions of the final product and the amount of radiopacity to be imparted to the polymer.
  • the heavy metals of the present invention are homogeneously distributed in the pol at the molecular level to form optically lucent radiopaque materials.
  • the hydrophobic nature of the heavy metal comp renders them virtually nonleachable from the resin into an aqueous environment to which the composites of this invent may be exposed.
  • Non-leachability into many other solvents be achieved by incorporating a polymerizable radiopacifyin agent into the polymer backbone, either by addition polymerization or by condensation polymerization.
  • the present invention also contemplates the addit of cross-linking agents. This will provide even greater resistance to leaching of the heavy metal compound from th polymer.
  • Suitable representative examples of cross-linkin agents include tetraethylene glycol dimethacrylate (TEG) , divinylbenzene, bisphenol-A-glycidyl methacrylate (BisGMA) the like.
  • TEG tetraethylene glycol dimethacrylate
  • divinylbenzene divinylbenzene
  • bisphenol-A-glycidyl methacrylate bisphenol-A-glycidyl methacrylate
  • the linear radiopaque polymeric materials have molecular weights generally ranging from 10,000 to about
  • the methods for preparing the homogene radiopaque polymers of the present invention include: a) polymerization at high temperatures; b) room temperature polymerization; c) suspension or emulsion polymerization; d) solvent casting; and e) compounding followed by melt processi Bulk polymerization involves dissolving the heavy metal compound in the monomer(s) and polymerizing in the " presence of an initiator like benzoyl peroxide, azobisisobutyronitrile (AIBN), etc.
  • an initiator like benzoyl peroxide, azobisisobutyronitrile (AIBN), etc.
  • the heavy metal compound and an initiator are dissolved in the monomer, such as, for example, styrene, and bulk polymerized at elevated temperatures.
  • the monomer such as, for example, styrene
  • This high temperature bulk method is especiall adaptable for industrial uses.
  • the heavy metal organic compounds can be dissolved in styrene and polymerized with AI at the desired temperature.
  • Room temperature polymerization can be utilized in this invention since, unlike the bismuth salts previously use to impart radiopacity, the radiopacifying organometallic compounds of this invention do not interfere with the room temperature polymerizations in which a peroxide initiator is
  • th 7 homogeneous organometallic-polymer composites may be formed b g film casting methods and solvent evaporation.
  • Incorporation Q triphenyl bismuth, for instance, in poly(methyl methacrylate) 0 to form films or transparent radiopaque shields can be 036 I O
  • Radiopaque polyesters of the present invention may prepared by dissolving the heavy metal organic compound in polyol, such as, for example, ethylene glycol. The dissolv organometallic compound is then mixed with a dicarboxylic a such as terephthalic acid or phthalic anhydride, and polymerized at elevated temperatures in the presence of a k catalyst.
  • a dicarboxylic a such as terephthalic acid or phthalic anhydride
  • radiopaque heavy meta compound polymer composites have a wide variety of applicat especially in the dental and medical field.
  • radiopaque polymers may be employed in resin systems having levels of cross-linking which, for purposes of the present invention, range from 0 to about 5 percent, and denser more rigid structures having a higher degree of cross-linking ranging from more than 5 to about 15 percent.
  • Such systems include "self-curing 11 type resins which react at ambient temperatures of between 25 and 30"C, and systems which cure elevated temperatures with the application of heat.
  • the heavy metal-polymer composite would be ground to a fine powder and used as a ' component of a two-part system. More specifically, in the two-part system the composition is furnished in two separate containers.
  • the first container would comprise a powder containing a mixture of the radiopaque polymer complex previously described, fillers and an initiator, such as benzo peroxide or AIBN.
  • the second container comprises a liquid containing methyl methacrylate monomer, an amine acceleratorator a a cross-linking agent such as ethylene glycol dimethacrylate.
  • radiopaque polymer complex When the solutions are mixed, or when in the absence of amine accelerator they are exposed to a strong visible light, the radiopaque polymer complex will swell in the methyl methacrylate monomer and polymerize into a solid homogeneous polymeric mass.
  • Applications for the radiopaque polymer composites having low levels of cross-linking include removable dental devices like dentures, bite splints, night guards, orthodontic space maintainers, maxillofacial devices and other nonfixed devices where there is a risk of accidental impaction into the respiratory or digestive tracts.
  • radiopaque polymer composites having low levels of cross-linking can also be formulated into bone cements for bonding implanted devices to bone tissues so as to permit monitoring by noninvasive methods
  • the second category for biomedical resins include highly cross-linked structures where radiopacity is also a desirable property. They include fixed structures like restorative resins, veneering facings for dental crowns and
  • the radiopaque polymer composites may be used with all body implants, prosthetic devices and appliances w are presently used with radiolucent plastics, such as, for example, catheters, bone implants, heart valves or arteries
  • Industrial applications for the radiopaque composi of the present invention include x-ray and other radiation shielding devices.
  • the transparent radiopaque polymers which are also opaque to U/V radiation, can be us in such areas as aircraft windows and cabins for shielding pilots and astronauts from high energy ⁇ /V and x-radiation found at high altitudes.
  • Transparent shielding devices mad sheets of radiopaque plastics for workers exposed to x-rays other forms of potentially harmful radiation are also inten utilities.
  • the radiopaque polyester fibers are especially useful in textiles and fabrics for making specialized radiopaque garments to be worn by workers exposed to radia in the job place.
  • the radiopaque polymers can be incorporated into any plastic device which requires detect by x-rays.
  • the composites of this invention ca be incorporated into plastic firearms to ensure detection by airport security x-ray devices.
  • the following specific examples demonstrate the radiopaque polymers and resin compositions, and are representative of the various methods for producing them. However, it is to be understood that these examples are for illustrative purposes only and do not purport to be wholly definitive as to conditions and scope.
  • the radiopaque polymers of Examples I-VII were teste to develop data on the possible presence of free triphenylbismuth and the effects of dissolved triphenyl bismu on the glass transition temperature of poly(methyl methylacrylate) by differential scanning calorimetry using a Perkin-Elmer DSC-4 instrument. Scans were run from 50 to 150 with a scan rate of 20°C per minute. A sample of poly(methyl methylacrylate) containing no triphenylbismuth was used as a control for comparison purposes. The results of the DSC 036 analyses are also reported in Table A.
  • the radiopacity of the composites of EXAMPLES I-VI was tested as follows: Samples of EXAMPLES I-VII were cut cylindrical pellets of 1 mm and 2 mm thickness. The pellet were polished and placed on a Kodak X-ray film along with a aluminum stepwedge with 1mm steps. The pellets were place inches below the cathode ray tube of an X-ray apparatus an VA* ⁇ exposed to 90 kv 6 nja-s X-rays. Using a microfilm densitom the X-ray absorption of the pellets was then compared with of the aluminum stepwedge.
  • Room temperature polymerization in accordance with this invention was performed by dissolving the organometallic compound in the monomer, followed by addition of an initiator and an amine accelerator to form the polymer-organometallic composite.
  • the composite of EXAMPLE VIII was prepared according to the following procedure: in a test tube 0.25 grams of triphenylbismuth was dissolved in 0.9 grams of methyl methacrylate to form a clear, homogeneous and transparent solution. Benzoylperoxide, an initiator, was the added to the mixture in an amount of .025 grams or 2.5 weight percent based on the monomer.
  • the films formed by this method were transparent, clear and homogeneous. IR spectra of the samples of Examples IX and X show no trace of solvent (THF) left in the film.
  • the solvent casting procedure may be used to incorporate organometallic compounds into many other polymer The choice of solvents is dependent on the solubility of the polymers and organometallic compounds in the solvents. For example, an appropriate solvent for incorporating triphenylbismuth into polyacrylonitrile by solvent casting i dimethyl formamide (at 70°C), and for preparing polyethylene-triphenylbismuth composites hexane is an appropriate solvent.
  • Radiopaque characteristics may also be imparted to polymers according to this invention by compounding polymer a an organometallic compound followed by melt processing to incorporate heavy metal organometallic compounds into polymers.
  • the composites of EXAMPLES XI-XIV were prepared by first mixing (compounding) the triphenylbismuth into isotacti polypropylene and then transferring the mixture to a test tube. The mixture is sealed and the test tube is evacuated. , The mixture is heated above its melting point and kept at tha temperature for a few hours to give a homogeneous, clear and transparent mixture. The mixture on cooling becomes opaque, is pure isotactic polypropylene.
  • the weight percent of triphenylbismuth in isotactic polypropylene for EXAMPLES XI-X are shown in TABLE B.
  • the isotactic polypropylene-triphenylbismuth samples of EXAMPLES XI-XIV were cut in cylindrical pellets of 1 mm an 2 mm thickness.
  • the radiopacity of the samples was measured the same way as described above in regards to EXAMPLES I-VII this invention. It was found that 35 percent by weight triphenyl bismuth was required in a 2mm pellet to provide th same radiopacity as a 2mm pellet of aluminum.
  • the thermal properties of the samples of EXAMPLES XI-XIV were tested using the procedures described above in regard to EXAMPLES I-VII.
  • the control in this case is pure isotactic polypropylene.
  • the results are also shown in TABL TABLE B
  • Diphenyl p-styryl bismuth synthesized according t known procedures, was copolymerized with methyl methacrylat bulk with AIBN at 65*C to give a transparent, hard and clea copolymer. Because the monomer-containing heavy metal is p of the backbone of the product, it improves the thermal and mechanical properties of polymers in comparison to material containing heavy metal components as additives only. Its permanent, chemical incorporation into the polymer structur prevents the leaching out of the heavy metal X-ray contrast agent in any kind of solvent ,
  • copoly ers were formed using the same procedu given for EXAMPLE XV to " yield poly(methylmethacrylate-co- diphenyl p-styryl bismuth) with different weight percent (or molar ratio) of heavy metal monomer. These copolymers were c in cylindrical pellets of 1mm and 2mm thickness. The radiopacities of the pellets, were measured the same way as mentioned above in regard to Part C Examples I-VII of this invention. It was found that for this copolymer a 2mm thick pellet containing 26 wt% of the bismuth-containing monomer ga the same radiopacity ⁇ 2 mm thick aluminum.
  • the Tg of his copolymer was 110*C, close to that of pure poly(methylmethacr late) , a considerable improvement of the Tg of 85 * C (Table A, Example VI) for a composite of poly (methyl methacrylate) and fawe triphenylbismuth.
  • the organometallic radiopacifying compounds includedin the radiopacifying monomers of this invention do not interfer with room cured polymerization procedures utilizing amine accelerators.
  • EXAMPLE XVI was prepared by the room temperatu polymerization of methyl methacrylate which contained 30 wei 036 «
  • the copolymer formed by this method has the same transparen homogeneity, and mechanical and thermal properties as that formed in EXAMPLE XV of this invention.

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  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

L'invention concerne de nouveaux matériaux radio-opaques ainsi qu'un procédé de préparation de ces matériaux. Les matériaux radio-opaques sont des composites de polymères et de composés organiques contenant des métaux lourds, lesquels métaux lourds recèlent des composés ayant la formule (I), dans laquelle X est un métal lourd; R1, R2 et R3 peuvent être identiques ou différents et sont sélectionnés individuellement dans un groupe incluant un phényle, des phényles à substitution halogène, des phényles à substitution alkyle, des phényles à substitution aryle, des phényles à substitution ester, des phényles à substitution alcène, des groupes silyle et de l'acrylate de méthyle, et R3 peut en outre être sélectionné dans le groupe incluant un halogène, un alkyle, un alcène, un ester et l'acide carboxylique lorsque R3 est différent de R1 et de R2. Les composites qui sont permanents et non lixiviables, n'affectent pas les propriétés mécaniques et physiques des compositions. Ils sont utiles en tant que résines à usage médical et dentaire, dans la fabrication d'appareils médicaux et dentaires, de dispositifs prothétiques, de dispositifs de protection contre les radiations et de tissus en polyester radio-opaques pour la fabrication de vêtements.
EP19890911685 1988-09-12 1989-09-12 Homogeneous radiopaque polymer-organobismuth composites Withdrawn EP0387348A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US24342688A 1988-09-12 1988-09-12
US243426 1988-09-12

Publications (2)

Publication Number Publication Date
EP0387348A1 true EP0387348A1 (fr) 1990-09-19
EP0387348A4 EP0387348A4 (en) 1992-07-08

Family

ID=22918741

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890911685 Withdrawn EP0387348A4 (en) 1988-09-12 1989-09-12 Homogeneous radiopaque polymer-organobismuth composites

Country Status (2)

Country Link
EP (1) EP0387348A4 (fr)
WO (1) WO1990003036A1 (fr)

Families Citing this family (15)

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CN1037788C (zh) * 1992-12-19 1998-03-18 天津纺织工学院 中子和γ射线屏蔽纤维的制造方法
JP3668983B2 (ja) * 1993-08-23 2005-07-06 日産化学工業株式会社 トリス（置換フェニル）ビスマス誘導体
US5939045A (en) * 1994-12-22 1999-08-17 Nissan Chemical Industries, Ltd. Organic bismuth derivatives for X-ray imaging
FR2755440B1 (fr) * 1996-11-07 1999-01-15 Tuffet Sophie Procede de conservation de longue duree de molecules d'adn et conditionnement pour sa mise en oeuvre
NZ507970A (en) * 1998-05-06 2003-09-26 Sophie Tuffet Method for prolonged storage of DNA molecules and packaging implementing said method
DE10004832A1 (de) * 2000-01-31 2001-08-16 Ethicon Gmbh Flächiges Implantat mit röntgensichtbaren Elementen
US8088158B2 (en) 2002-12-20 2012-01-03 Boston Scientific Scimed, Inc. Radiopaque ePTFE medical devices
WO2006026725A2 (fr) 2004-08-31 2006-03-09 C.R. Bard, Inc. Greffe en polytetrafluorethylene (ptfe) auto-etanche a resistance au tortillement
WO2007001472A2 (fr) 2005-06-17 2007-01-04 C. R. Bard, Inc. Greffon vasculaire avec une résistance au pliage après le clampage
EP1945138A4 (fr) 2005-11-09 2010-02-10 Bard Inc C R Greffons et stents-greffons presentant un marqueur radio-opaque
DE202010003032U1 (de) * 2010-02-17 2011-08-12 Ernst Mühlbauer Gmbh & Co. Kg Infiltrationslösung zur Behandlung einer Zahnschmelzläsion
US10026513B2 (en) * 2014-06-02 2018-07-17 Turner Innovations, Llc. Radiation shielding and processes for producing and using the same
WO2018093566A1 (fr) * 2016-11-16 2018-05-24 The United States Of America, As Represented By The Secretary, Department Of Health And Human Services Particules pouvant être imagées, procédés de fabrication et procédés d'utilisation de celles-ci
JP7521524B2 (ja) * 2019-03-28 2024-07-24 三菱瓦斯化学株式会社 光学材料用重合性組成物
JP2022128912A (ja) * 2021-02-24 2022-09-05 三菱瓦斯化学株式会社 重合性組成物及びそれを重合硬化してなる樹脂

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US2833741A (en) * 1956-03-29 1958-05-06 H D Justi & Son Inc Method of polymerizing acrylate esters in the presence of an organo-metallic inhibitor
US3609372A (en) * 1963-06-04 1971-09-28 Marxen Friedrich Shaped polymeric shield against neutron and gamma radiation
US3577346A (en) * 1968-11-14 1971-05-04 Minnesota Mining & Mfg Insulated electrical conductors having corona resistant polymeric insulation containing organo metallic compounds

Non-Patent Citations (2)

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Title
No further relevant documents have been disclosed *
See also references of WO9003036A1 *

Also Published As

Publication number Publication date
WO1990003036A1 (fr) 1990-03-22
EP0387348A4 (en) 1992-07-08

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