Solid Polymer Derived From Carboxylic Acid Cyclic Ester, E.g., Lactone, Etc. Patents (Class 525/415)
  • Patent number: 5550209
    Abstract: Disclosed are a lactone polymer, a carbonate polymer, a lactone-carbonate random or block copolymer which are mono-dispersed, that is, which have a molecular weight distribution of nearly 1, or, in which purity of a polymer component having a unitary structure is very high, and processes for the preparation thereof which comprise a ring-opening addition reaction of a lactone monomer and/or a cyclic carbonate monomer with a ring-opening initiator in the presence of an organic aluminum-based Lewis acid represented by general formula (I), ##STR1## wherein R is an alkyl group having a carbon number ranging from 1 to 4, Y is independently selected from a substituted group, and p is any one of 1, 2 and 3.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: August 27, 1996
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Shohei Inoue, Takuzo Aida, Masaki Akatsuka
  • Patent number: 5550173
    Abstract: A polymer composition comprising at least one structural polymer and at least one oligomer of at least one polymer selected from the group; polyhydroxyalkanoates, polylactide, polycaprolactone and co-polymers thereof.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: August 27, 1996
    Assignee: Zeneca Limited
    Inventors: Timothy Hammond, Jasbinder S. Bal
  • Patent number: 5539081
    Abstract: A lactide polymer composition combining compositional and purity limitations and catalyst optimization or addition of stabilizing agents resulting in a melt-stable polymer is disclosed. The melt-stable lactide polymer comprises a plurality of polylactide polymer chains, residual lactide in concentration of less than 2 percent and water in concentration of less than 1000 parts-per-million. A stabilizing agent in an amount sufficient to reduce depolymerization of the lactide polymer during melt-processing or alternatively, control of catalyst level at a molar ratio of monomer to catalyst greater than 3000:1 is also included in the melt-stable composition. A process for manufacture of a melt-stable lactide polymer composition includes polymerizing a lactide mixture and adding stabilizing agents sufficient to reduce depolymerization of the polylactide during melt-processing, followed by devolatilizing the polylactide to remove monomer and water.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: July 23, 1996
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Eric S. Hall, Robin S. Eichen Conn, Christopher M. Ryan
  • Patent number: 5536564
    Abstract: The present invention relates to biodegradable PHA copolymers comprising at least two randomly repeating monomer units (RRMU) wherein the first RRMU has the structure ##STR1## wherein R.sup.1 is H or C.sub.2 alkyl, and n is 1 or 2; the second RRMU has the structure ##STR2## ; and wherein at least 50% of the RRMUs have the structure of the first RRMU. The present invention further relates to plastic articles comprising said biodegradable PHA copolymers. The present invention further relates to an absorbent article comprising a liquid pervious topsheet, a liquid impervious backsheet comprising a film comprising a PHA of the present invention and an absorbent core positioned between the topsheet and the backsheet.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: July 16, 1996
    Assignee: The Procter & Gamble Company
    Inventor: Isao Noda
  • Patent number: 5536807
    Abstract: A semi-crystalline film comprised of a lactide polymer. The lactide polymer comprises a plurality of poly(lactide) polymer chains, residual lactide in concentration of less than about 5 percent and water in concentration of less than about 2000 parts-per-million. A process for manufacturing a semi-crystalline film with the lactide polymer composition is also disclosed.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: July 16, 1996
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Christopher M. Ryan
  • Patent number: 5530074
    Abstract: This invention relates to materials for medical or veterinary use that possess considerably improved properties with regard to friction. The invention also relates to the production of such materials from existing materials that possess suitable bulk properties, but inappropriate frictional properties. This invention also relates to a hydrophilic coating material that provides improved frictional properties.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 25, 1996
    Assignee: American Cyanamid Company
    Inventors: Peter K. Jarrett, George Jessup, Louis Rosati, Chris Martin, John W. Maney
  • Patent number: 5525706
    Abstract: A nonwoven fabric comprised of a lactide polymer. The lactide polymer comprises a plurality of poly(lactide) polymer chains, residual lactide in concentration of less than about 2 percent and water in concentration of less than about 2000 parts-per-million. A process for manufacturing a nonwoven fabric with the lactide polymer composition is also disclosed.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: June 11, 1996
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Christopher M. Ryan, Eric S. Hall, Robin S. Eichen Conn
  • Patent number: 5525646
    Abstract: This invention relates to a bioresorbable material and an article of manufacture of such material for medical use comprising homopolymers, copolymers, or a blend thereof selected from the group of monomers including glycolic acid, lactic acid, caprolactone, trimethylene carbonate, paradioxanone and 1,5 dioxepan-2-one, a plasticizer selected from the group including ethyl, butyl and hexyl esters of acetylated or non-acetylated citric acid, ethyl terminated oligomers of lactic acid, having no less than 2 and no more than 10 units, and lactic acid esters of glycerol, the material comprises 50% of amorphous polymer or polymers to impart to the material plastic malleability substantially without memory.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: June 11, 1996
    Inventors: Dan Lundgren, Jan Gottlow, Torbjorn Mathisen
  • Patent number: 5522842
    Abstract: Crystalline, low melting .epsilon.-Caprolactone polymers which undergo accelerated hydrolysis for use, for example, as absorbable coatings for surgical sutures; the polymers bearing basic amine functionalities, ionically or covalently linked to the ester chain, which induce autocatalyzed hydrolysis.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: June 4, 1996
    Assignee: Poly-Med, Inc.
    Inventor: Shalaby W. Shalaby
  • Patent number: 5522841
    Abstract: Block copolymers have one of the block made from hard phase forming monomers and another block made from soft phase forming monomers copolymerized with randomly intermingled units of other soft phase forming monomers. Particularly useful copolymers are initiated with a polyalkylene oxide initiator. The copolymers are useful in forming surgical articles, including both monofilament and multifilament sutures.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: June 4, 1996
    Assignee: United States Surgical Corporation
    Inventors: Mark S. Roby, Cheng-Kung Liu, Steven L. Bennett
  • Patent number: 5516920
    Abstract: The invention described novel compounds of formula ##STR1## wherein the general symbols are as defined in claim 1, as stabilisers for protecting organic materials, in particular polymers and lubricants, against thermal, oxidative or light-induced degradation.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: May 14, 1996
    Assignee: Ciba-Geigy Corporation
    Inventors: Peter Nesvadba, Samuel Evans, Christoph Krohnke, Jurg Zingg
  • Patent number: 5508378
    Abstract: A method for producing a polylactic acid of the present invention includes the steps of (a) polymerizing a lactide used as a main starting material in a molten state to give a polylactic acid; and (b) further polymerizing the polylactic acid obtained in step (a) in a solid phase by heating at a temperature lower than a melting point of a final polymer product.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: April 16, 1996
    Assignee: Shimadzu Corporation
    Inventors: Hitomi Ohara, Seiji Sawa, Tatsushi Kawamoto
  • Patent number: 5502116
    Abstract: The present invention relates to biodegradable PHA copolymers comprising at least two randomly repeating monomer units (RRMU) wherein the first RRMU has the structure ##STR1## wherein R.sup.1 is H or C.sub.2 alkyl, and n is 1 or 2; the second RRMU has the structure ##STR2## and wherein at least 50% of the RRMUs have the structure of the first RRMU. The present invention further relates to plastic articles comprising said biodegradable PHA copolymers. The present invention further relates to an absorbent article comprising a liquid pervious topsheet, a liquid impervious backsheet comprising a film comprising a PHA of the present invention and an absorbent core positioned between the topsheet and the backsheet.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 26, 1996
    Assignee: The Procter & Gamble Company
    Inventor: Isao Noda
  • Patent number: 5502159
    Abstract: A block copolymer for use in the fabrication of bioabsorbable articles such as monofilament surgical sutures is prepared by copolymerizing one or more hard phase forming monomers and 1,4-dioxan-2-one, and then polymerizing one or more hard phase forming monomers with the dioxanone-containing copolymer.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: March 26, 1996
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, Steven L. Bennett, John Kennedy, Donald S. Kaplan, Ross R. Muth
  • Patent number: 5500465
    Abstract: Compatibilized blends of a biodegradable hydrophobic polyester, unmodified starch or other similar polysaccharide containing less than 1% water by weight, other biodegradable polymers that may be hydrophobic, plasticizer, and other additives. The blends are produced in the absence of water. The preferred polyester polymer is poly(.epsilon.-caprolactone) and the preferred starch is from corn. A small amount of a unique stretching agent is incorporated to provide high elongations at break, especially in film forming compositions containing a significant amount of starch. The starch is a discontinuous phase that may be completely or partially plasticized and the polyester polymer is the continuous phase. The preferred polymers have unique film forming properties and are resistant to water and moisture.
    Type: Grant
    Filed: March 10, 1994
    Date of Patent: March 19, 1996
    Assignee: Board of Trustees operating Michigan State University
    Inventors: Mohan Krishnan, Ramani Narayan
  • Patent number: 5498379
    Abstract: Shaped hydrogel articles such as soft contact lenses are prepared by the steps of:(1) molding or casting a polymerization mixture comprising:(a) a monomer mixture comprising a major proportion of one or more hydrophilic monomers such as 2-hydroxyethyl methacrylate, and one or more cross-linking monomers; and(b) an inert, displaceable diluent selected from the group consisting of:(i) ethoxylated alkyl glucoside;(ii) ethoxylated bisphenol A;(iii) polyethylene glycol;(iv) mixture of propoxylated and ethoxylated alkyl glucoside;(v) single phase mixture of ethoxylated or propoxylated alkyl glucoside and C.sub.2-12 dihydric alcohol;(vi) adduct of .epsilon.-caprolactone and C.sub.2-6 alkanediols and triols;(vii) ethoxylated C.sub.3-6 alkanetriol; and(viii) mixtures of one or more of (i) through (vii),under conditions to polymerize said monomer mixture to produce a shaped gel of a copolymer of said monomers and said diluent; and(2) thereafter replacing said diluent with water.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: March 12, 1996
    Assignee: Johnson & Johnson Vision Products, Inc.
    Inventors: Ivan M. Nunez, Frank F. Molock, Laura D. Elliott, James D. Ford
  • Patent number: 5489651
    Abstract: "Living" polymerization methods are described wherein a bimetallic lanthanide complex initiator is reacted with a monomer. Using these methods, link-functionalized polymers can be formed that are capable of being modified after polymerization with various reactants, or to be biodegraded through oxidation or reduction or cleavage. The bimetallic lanthanide complex initiator can be used to polymerize methyl methacrylate in a living fashion. A two-step method of forming a triblock polymer using the bimetallic lanthanide complex initiator is also disclosed.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: February 6, 1996
    Assignee: The Regents of the University of California
    Inventors: Bruce M. Novak, Lisa S. Boffa
  • Patent number: 5484881
    Abstract: An amorphous film comprised of a lactide polymer. The lactide polymer comprises a plurality of poly(lactide) polymer chains, residual lactide in concentration of less than about 2 percent and water in concentration of less than about 2000 parts-per-million. A process for manufacturing an amorphous film with the lactide polymer composition is also disclosed.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: January 16, 1996
    Assignee: Cargill, Inc.
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Christopher M. Ryan, Eric S. Hall, Robin S. Eichen Conn
  • Patent number: 5480868
    Abstract: A sustained-release preparation which comprises a physiologically active peptide of general formula ##STR1## wherein X represents an acyl group; R.sub.1, R.sub.2 and R.sub.4 each represents an aromatic cyclic group; R.sub.3 represents a D-amino acid residue or a group of the formula ##STR2## wherein R.sub.3 ' is a heterocyclic group; R.sub.5 represents a group of the formula --(CH.sub.2).sub.n --R.sub.5 ' wherein n is 2 or 3, and R.sub.5 ' is an amino group which may optionally be substituted, an aromatic cyclic group or an O-glycosyl group;R.sub.6 represents a group of the formula --(CH.sub.2).sub.n --R.sub.6 ' wherein n is 2 or 3, and R.sub.6 ' is an amino group which may optionally be substituted;R.sub.7 represents a D-amino acid residue or an azaglycyl residue; andQ represents hydrogen or a lower alkyl group, or a salt thereof and a biodegradable polymer having a terminal carboxyl group.
    Type: Grant
    Filed: December 7, 1993
    Date of Patent: January 2, 1996
    Assignee: Takeda Chemical Industries, ltd.
    Inventors: Shigeru Kamei, Yasutaka Igari, Yasuaki Ogawa
  • Patent number: 5475080
    Abstract: A lactide polymer coating resulting in a strong, repulpable, high gloss, paper coating. The lactide polymer comprises a plurality of poly(lactide) polymer chains, residual lactide in concentration of less than about 5 percent and water in concentration of less than about 2000 parts-per-million. A process for coating paper with the lactide polymer composition is also disclosed.
    Type: Grant
    Filed: March 22, 1993
    Date of Patent: December 12, 1995
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Christopher M. Ryan, Eric S. Hall, Robin S. Eichen Conn
  • Patent number: 5475063
    Abstract: Polymer blends of glycolide and/or lactide homopolymer and/or glycolide/lactide copolymer and polycaprolactone and/or polytrimethylene carbonate homopolymer or copolymers thereof and absorbable surgical devices manufactured therefrom having improved mechanical properties, such as improved impact resistance and improved cyclic flex, are disclosed. The blends may be prepared by polymerizing a glycolide or lactide containing polymer in the presence of a polymer derived from trimethylene carbonate or .epsilon.-caprolactone.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: December 12, 1995
    Assignee: United States Surgical Corporation
    Inventors: Donald S. Kaplan, Matthew Hermes, Ross R. Muth, John Kennedy
  • Patent number: 5472818
    Abstract: Spherical resin particles having a sharp particle size distribution and a method for producing such particles are disclosed. Resin particles according to this invention contain at least a polyester polymer and a polymer formed from a polymerizable monomer, and have an average diameter (D) of 1 to 500 .mu.m. At least 70% by weight of the particles have a diameter in the range of 0.5 D to 2.0 D. Such resin particles can be produced by swelling polyester-containing seed particles with a polymerizable monomer and then polymerizing the polymerizable monomer in swelled seed particles.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: December 5, 1995
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasunari Hotta, Satoshi Maeda, Yozo Yamada, Shinichiro Mori, Toshio Tanaka, Koji Tanaka, Hiroshi Ono
  • Patent number: 5470944
    Abstract: A degradable high molecular weight poly(lactic acid). A poly(lactic acid) has a terminal end group of one of carboxyl or hydroxyl groups with low molecular weight poly(lactic acid) units coupled with linking agents of di-isocyanates, bis-epoxides, bis-oxazolines and bis-ortho esters. The resulting high molecular weight poly(lactic acid) can be used for applications taking advantage of the improved physical properties.
    Type: Grant
    Filed: February 13, 1992
    Date of Patent: November 28, 1995
    Assignee: ARCH Development Corporation
    Inventor: Patrick V. Bonsignore
  • Patent number: 5468253
    Abstract: Medical devices or components for medical devices formed from bioabsorbable elastomers comprising a random copolymer are disclosed. The random copolymer is a copolymer of from about 30 to about 70 weight percent of: a) .epsilon.-caprolactone, trimethylene carbonate, an ether lactone, or a mixture of these, and b) the balance being substantially glycolide, para-dioxanone, or a mixture of these. The random copolymers surprisingly exhibit elastomeric properties, and the copolymers are bioabsorbable. The combination of physical and biological properties of these elastomeric copolymers are particularly well-suited for numerous medical and surgical applications.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: November 21, 1995
    Assignee: Ethicon, Inc.
    Inventors: Rao S. Bezwada, Angelo G. Scopelianos
  • Patent number: 5466444
    Abstract: The invention relates to the use of copolymers of racemic lactide and .epsilon.-caprolactone, .delta.-valerolactone, gamma-decalactone or .beta.-hydroxybutyric acid, prepared by the reaction of the monomers in the molar ratio of lactide to reaction partner of approximately 95-70 to 5-30, with the addition of metal carboxylates, known per se, as initiators at temperatures of approximately 150.degree. C. over a period of time of approximately 16 to 18 hours, for the topical treatment of human or animal skin.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: November 14, 1995
    Inventor: Christian Jurgens
  • Patent number: 5457144
    Abstract: This invention provides hydrolytically labile polyamide compositions and articles containing an ester derived moiety in the polymer backbone which will degrade after exposure to water over long periods of time.
    Type: Grant
    Filed: February 2, 1994
    Date of Patent: October 10, 1995
    Assignee: Rohm and Haas Company
    Inventors: Norman L. Holy, Newman M. Bortnick
  • Patent number: 5446123
    Abstract: A lactide polymer composition combining compositional and purity limitations and catalyst optimization or addition of stabilizing agents resulting in a melt-stable polymer is disclosed. The melt-stable lactide polymer comprises a plurality of polylactide polymer chains, residual lactide in concentration of less than 2 percent and water in concentration of less than 1000 parts-per-million. A stabilizing agent in an amount sufficient to reduce depolymerization of the lactide polymer during melt-processing or alternatively, control of catalyst level at a molar ratio of monomer to catalyst greater than 3000:1 is also included in the melt-stable composition. A process for manufacture of a melt-stable lactide polymer composition includes polymerizing a lactide mixture and adding stabilizing agents sufficient to reduce depolymerization of the polylactide during melt-processing, followed by devolatilizing the polylactide to remove monomer and water.
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: August 29, 1995
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Jeffrey J. Kolstad, Eric S. Hall, Robin S. Eichen Conn, Christopher M. Ryan
  • Patent number: 5442032
    Abstract: This invention provides various copolymers comprising a repeating unit of the chemical formula:(CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.2 CO.sub.2)and other repeating units having a chemical formula selected from the group consisting of:(CHRCO.sub.2),([CH.sub.2 ].sub.5 CO.sub.2),(CH.sub.2 CH.sub.2 OCH.sub.2 CO.sub.2),(CH.sub.2 CH.sub.2 CH.sub.2 OCO.sub.2), andcombinations of two or mope thereof wherein R is a hydrogen atom or a methyl group and the first repeating unit is less than 45 weight percent of the total weight of the copolymer. This invention also relates to use of these copolymers in the fabrication of absorbable surgical devices such as sutures and as coatings for medical devices.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: August 15, 1995
    Assignee: Ethicon, Inc.
    Inventors: Steven C. Arnold, Rao S. Bezwada, Alastair W. Hunter
  • Patent number: 5442033
    Abstract: A copolymer of from in the range of from about 55 to about 70 weight percent lactide and from in the range of from about 45 to about 30 mole percent .epsilon.-caprolactone suitable for use in biomedical applications such as drug delivery, coatings for surgical sutures and needles, and lubricants for medical devices.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: August 15, 1995
    Assignee: Ethicon, Inc.
    Inventor: Rao S. Bezwada
  • Patent number: 5442016
    Abstract: This invention relates to materials for medical or veterinary use that possess considerably improved properties with regard to friction. The invention also relates to the production of such materials from existing materials that possess suitable bulk properties, but inappropriate frictional properties. This invention also relates to a hydrophilic coating material that provides improved frictional properties.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: August 15, 1995
    Assignee: American Cyanamid Company
    Inventors: Peter K. Jarrett, George Jessup, Louis Rosati, Chris Martin, John W. Maney
  • Patent number: 5439985
    Abstract: A biodegradable and hydrodegradable diblock copolymer includes a naturally-occurring poly(.beta.-alkanoate) component and a chemically synthesized polyester component formed by ring-opening polymerization. A method of forming the biodegradable and hydrodegradable diblock copolymer having a poly(.beta.-hydroxyalkanoate) component and a chemically synthesized polyester component includes exposing a naturally-occurring poly(.beta.-hydroxyalkanoate) to alcoholysis and then to a trialkyl metal to form a dialkyl metal poly(.beta.-hydroxyalkanoate) macroinitiator. The macroinitiator is then reacted with a lactone or lactide reactant to form the biodegradable and hydrodegradable diblock copolymer.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: August 8, 1995
    Assignee: University of Massachusetts Lowell
    Inventors: Richard A. Gross, Stephen P. McCarthy, Michael S. Reeve
  • Patent number: 5440007
    Abstract: High molecular weight, biodegradable polymers of substituted-poly(.beta.-propioesters), wherein the repeat unit sequences have a predominantly syndiotactic arrangement and a method of forming such polymers are disclosed. The method includes exposing a substituted-.beta.-propiolactone to a tin-based organometallic catalyst for a sufficient combination of time and temperature to form the predominantly syndiotactic substituted-poly(.beta.-propioester).
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: August 8, 1995
    Assignee: University of Massachusetts Lowell
    Inventors: Richard A. Gross, John E. Kemnitzer, Stephen P. McCarthy
  • Patent number: 5434242
    Abstract: The invention relates to resorbable homopolymers and copolymers which are substantially free from polymerization catalysts and processes for preparing them.
    Type: Grant
    Filed: December 12, 1994
    Date of Patent: July 18, 1995
    Assignee: Boehringer Ingelheim GmbH
    Inventors: Dieter Bendix, Gunther Entenmann
  • Patent number: 5434241
    Abstract: This specification provides a biodegradable poly(lactic acid) of a star-shaped structure having a high molecular weight of more than 30,000 with excellent tensile strength and a process for its preparation which comprises direct polycondensation of lactic acid using polyhydroxyl compound having at least four hydroxyl groups.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: July 18, 1995
    Assignee: Korea Institute of Science and Technology
    Inventors: Young H. Kim, Kwang D. Ahn, Yang K. Han, Soo H. Kim, Jeong B. Kim
  • Patent number: 5431679
    Abstract: Block copolymers wherein one of the blocks is made from hard phase forming monomers and another of the blocks is made from soft phase forming monomers copolymerized with randomly intermingled units of other soft phase forming monomers. The copolymers are useful in forming surgical articles, including both monofilament and multifilament sutures.
    Type: Grant
    Filed: March 10, 1994
    Date of Patent: July 11, 1995
    Assignee: United States Surgical Corporation
    Inventors: Steven L. Bennett, Cheng-Kung Liu
  • Patent number: 5424346
    Abstract: The biodegradable polymer comprises polymerized lactic acid units of the structure: ##STR1## where n is an integer between 450 and 10,000 and the alpha carbon is a mixture of L- and D-configurations with a preponderance of either D- or L-units, wherein the polymer is suitable for replacement of polystyrene; the biodegradable composition also comprises blends of a physical mixture of polymerized lactic acid units of the formula I, where n is an integer between 450 and 10,000 and the alpha carbon is a mixture of L- and D-configurations with a preponderance of either D- or L-units, and a homopolymer of poly(D-lactic acid) or poly(L-lactic acid), and plasticizers that provide unique properties when intimately dispersed.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: June 13, 1995
    Assignee: Ecopol, LLC
    Inventor: Richard G. Sinclair
  • Patent number: 5420212
    Abstract: This invention relates to a polymer blend comprising:(a) a concentrate comprising a polycarbonate resin, polycaprolactone and a copolyester having repeat units derived from terephthalic acid, ethylene glycol and 1,4-cyclohexanedimethanol; and(b) a copolyester having repeat units derived from terephthalic acid, ethylene glycol and 1,4-cyclohexanedimethanol.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: May 30, 1995
    Assignee: Eastman Chemical Company
    Inventor: Ronald R. Light
  • Patent number: 5410016
    Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.
    Type: Grant
    Filed: March 1, 1993
    Date of Patent: April 25, 1995
    Assignee: Board of Regents, The University of Texas System
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill
  • Patent number: 5403897
    Abstract: A process for producing a lactic acid-based copolyester by the ring-opening copolymerization and transesterification of a lactide (A) with an aromatic polyester (B) and/or an aliphatic polyester (C) in the presence of a ring-opening polymerization catalyst (D), and a packaging material comprising the lactic acid-based copolyester obtained by the process are disclosed. According to the present invention, a lactic acid-based degradable copolyester which has a sufficiently high molecular weight and satisfactory toughness and also has suitable rigidity, pliability, and transparency according to applications can be produced. Further, a general-purpose packaging material, e.g., a sheet or film, which comprises the lactic acid-based copolyester produced by the process and is excellent in formability, degradability, and transparency can also be produced.
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: April 4, 1995
    Assignee: Dainippon Ink & Chemicals, Inc.
    Inventors: Hiroshi Ebato, Satoshi Oya, Yasutoshi Kakizawa, Hideyuki Furuta, Kosuke Arai
  • Patent number: 5403347
    Abstract: Block copolymers wherein one of the blocks is made from hard phase forming monomers and another of the blocks is made from soft phase forming monomers copolymerized with randomly intermingled units of other soft phase forming monomers. The copolymers are useful in forming surgical articles, including both monofilament and multifilament sutures. The block copolymer preferably comprising:a) a proportion of glycolic acid ester units as end blocks, andb) a center block comprising 1,4 dioxan-2-one randomly polymerized with 1,3 dioxane-2-one.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: April 4, 1995
    Assignee: United States Surgical Corporation
    Inventors: Mark S. Roby, Steven L. Bennett, Cheng-Kung Liu
  • Patent number: 5401778
    Abstract: A biodegradable plastic composition for forming biodegradable shaped bodies which includes a poly-.beta.-hydroxybutyrate having a viscosity of n.sub.A at 185.degree. C. and a polycaprolactone having a viscosity of n.sub.B at 185.degree. C., wherein the poly-.beta.-hydroxybutyrate is present in an amount C.sub.A of 10-45 or 55-85% by weight based on the total weight of the poly-.beta.-hydroxybutyrate and the polycaprolactone, and wherein n.sub.A, n.sub.B and C.sub.A satisfy the following condition:4.times.10.sup.-3 .times.C.sub.A -1.7.ltoreq.log (n.sub.A /n.sub.B).ltoreq.4.times.10.sup.-3 .times.C.sub.A -1.3.
    Type: Grant
    Filed: April 7, 1993
    Date of Patent: March 28, 1995
    Assignees: Director-General of Agency of Industrial Science and Technology, Mitsubishi Gas Chemical Co., Ltd.
    Inventors: Yutaka Tokiwa, Akira Iwamoto, Masahiro Harada, Shigeki Imagawa, Teizi Urakami
  • Patent number: 5399666
    Abstract: Star-block copolymers containing polycaprolactone and polylactide blocks of limited molecular weight are tough, easily degradable polymers. Such copolymers, which are noncrystalline and have glass transition temperatures near or below room temperature, are useful in many packaging and other applications.
    Type: Grant
    Filed: April 21, 1994
    Date of Patent: March 21, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Thomas M. Ford
  • Patent number: 5391707
    Abstract: Processes of producing 1,4-dioxan-2-one (p-dioxanone) are improved by the addition of a blocking agent to a crude reaction product containing p-dioxanone. The blocking agent reacts with unreacted starting materials in the crude reaction product to protect the active sites thereon with groups that do not initiate polymerization of p-dioxanone. The polymerization of p-dioxanone before its recovery from the process is thereby inhibited.
    Type: Grant
    Filed: December 10, 1993
    Date of Patent: February 21, 1995
    Assignee: United States Surgical Corporation
    Inventor: Ying Jiang
  • Patent number: 5382636
    Abstract: An internally plasticized vinyl chloride polymer with a polycaprolactone content ranging from 32 to 40% is prepared by polymerizing vinyl chloride in the presence of polycaprolactone. The graft copolymers show good transparency, homogeneity, and processing properties.The copolymers of the present invention can be used to produce materials used in medical applications, such as, blood bags and dialysis tubing.
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: January 17, 1995
    Assignee: Huels Aktiengesellschaft
    Inventors: Frank Schmidt, Neidhard Gardiewski
  • Patent number: 5382624
    Abstract: Spherical resin particles having a sharp particle size distribution and a method for producing such particles are disclosed. Resin particles according to this invention contain at least a polyester polymer and a polymer formed from a polymerizable monomer, and have an average diameter (D) of 1 to 500 .mu.m. At least 70% by weight of the particles have a diameter in the range of 0.5 D to 2.0 D. Such resin particles can be produced by swelling polyester-containing seed particles with a polymerizable monomer and then polymerizing the polymerizable monomer in swelled seed particles.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: January 17, 1995
    Assignee: Toyo Boseki Kabushiki Kaisha
    Inventors: Yasunari Hotta, Satoshi Maeda, Yozo Yamada, Shinichiro Mori, Toshio Tanaka, Koji Tanaka, Hiroshi Ono
  • Patent number: 5376102
    Abstract: A deformable surgical repair device is manufactured from a block or graft copolymer. The copolymer comprises a plurality of first linkages selected from the group consisting of glycolic acid ester and lactic acid ester linkages, and mixtures thereof, and a plurality of second linkages selected from the group consisting of 1,3-dioxan-2-one; 1,4-dioxan-2-one and .epsilon.-caprolactone linkages. The plurality of first linkages comprises at least about 50 up to about 90 mole percent of the copolymer. In an alternative Claim, the deformable surgical repair device is manufactured from a blend of a first and a second absorbable polymer. The first absorbable polymer comprises a plurality of linkages selected from the group consisting of glycolic acid ester and lactic acid ester linkages, and mixtures thereof. The second absorbable polymer comprises a plurality of linkages selected from the group consisting of 1,3-dioxan-2-one; 1,4-dioxan-2-one and .epsilon.-caprolactone linkages.
    Type: Grant
    Filed: January 13, 1992
    Date of Patent: December 27, 1994
    Assignee: American Cyanamid Co.
    Inventors: Peter K. Jarrett, Donald J. Casey
  • Patent number: 5360892
    Abstract: A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene and polyethylene glycols, propylene and polypropylene glycols, P-dioxanone, 1,5 dioxepan-2-one, 1,4 -oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide wherein the high molecular weight polyethylene oxide is present in the range of from about 2% by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures thereof to an agricultural site is also disclosed.
    Type: Grant
    Filed: August 5, 1993
    Date of Patent: November 1, 1994
    Assignee: Arch Development Corporation
    Inventors: Patrick V. Bonsignore, Robert D. Coleman
  • Patent number: 5359027
    Abstract: Polymers and copolymers of L(+) and D(-) lactic acid, with high molecular weight and in the absence of catalysts, are prepared by upgrading low molecular weight polymers in the solid state.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: October 25, 1994
    Assignee: Himont Incorporated
    Inventors: Gabriele Perego, Enrico Albizzati
  • Patent number: 5359026
    Abstract: A copolymerized poly(lactide) polymer. A lactide is copolymerized with an epoxidized fat, oil, or mixture thereof thereby resulting in poly(lactide) copolymers having improved processing properties over prior poly(lactide)s.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: October 25, 1994
    Assignee: Cargill, Incorporated
    Inventor: Patrick R. Gruber
  • Patent number: 5357035
    Abstract: A process for the continuous production of polylactide polymers from lactic acid which incorporates removal of water or a solvent carrier to concentrate the lactic acid feed followed by polymerization to a low-molecular-weight prepolymer. This prepolymer is fed to a reactor in which a catalyst is added to facilitate generation of lactide, the depolymerization product of polylactic acid. The lactide generated is continuously fed to a distillation system as a liquid or vapor wherein water and other impurities are removed. The resultant purified liquid lactide is fed directly to a polymerization process.
    Type: Grant
    Filed: September 16, 1993
    Date of Patent: October 18, 1994
    Assignee: Cargill, Incorporated
    Inventors: Patrick R. Gruber, Eric S. Hall, Jeffrey J. Kolstad, Matthew L. Iwen, Richard D. Benson, Ronald L. Borchardt