Abstract: An absorbable crystalline, monocentric polyaxial copolymer comprising a central carbon or nitrogen atom and at least three axes, each of which includes an amorphous flexible component adjacent and originating from the central atom and a rigid, crystallizable component extending outwardly from the amorphous, flexible component is disclosed along with the use of such copolymer in medical devices which may contain a bioactive agent. The present invention also relates to a suture, stents, stent mantles and sealing devices made from the polyaxial copolymer.

Abstract: An absorbable crystalline, monocentric polyaxial copolymer comprising a central carbon or nitrogen atom and at least three axes, each of which includes an amorphous flexible component adjacent and originating from the central atom and a rigid, crystallizable component extending outwardly from the amorphous, flexible component is disclosed along with the use of such copolymer in medical devices which may contain a bioactive agent. The present invention also relates to a suture, stents, stent mantles and sealing devices made from the polyaxial copolymer.

Abstract: A process for producing a lactic acid polymer of 15,000 to 50,000 in weight-average molecular weight, the content of polymeric materials having not more than about 5,000 in weight-average molecular weight therein being not more than about 5% by weight, characterized by hydrolyzing a high molecular weight lactic acid polymer, placing the resultant solution comprising the hydrolyzed product under a condition capable of precipitating the objective lactic acid polymer, separating the precipitated lactic acid polymer and collecting them. The lactic acid polymer is useful as a matrix for sustained-release preparations. The sustained-release microcapsule preparation encapsulating a physiologically active substance can fully prevent the initial excessive release of the physiologically active substance from the microcapsules and keep a stable release rate over a long period of time.

Abstract: The present invention includes photocurable, liquid polymers incorporating coumarin ester endgroups into their molecular structure, which polymers are crosslinked upon irradiation with ultraviolet light by photochemically allowed [2+2] cycloaddition reactions among the chain ends, and which crosslinked polymers are useful in the preparation of medical devices, tissue engineering scaffolds, drug delivery systems and, in particular, in vivo preparation of implants in an open surgical procedure or laproscopically.

Abstract: In polymerizing biodegradable polymer material, a compressed gas is used as a reaction solvent for a solution-polymerization, in order to prepare biodegradable polyester homopolymer and copolymer with a high molecular weight in a fine powder form with a particle size of 0.01˜1000 ?m.

Abstract: Compositions based on ?-caprolactone polymer, comprising at least one ?-caprolactone polymer and calcium carbonate. Process for preparing these compositions, which are used for manufacturing articles, in particular films, preferably obtained by extrusion blow-moulding or by flat-die extrusion.

Abstract: This invention relates to single-component and multi-component catalytic systems using aryl titanates. Aryl titanate compounds are useful as catalysts and co-catalysts in single-component and multi-component catalytic systems (e.g., for the polymerization of macrocyclic oligoesters and the depolymerization of polyesters). Multi-component catalytic systems using aryl titanates allow increased versatility in applications such as liquid molding.

Abstract: The present invention is directed to a process for making an absorbable polylactone copolymer prepared in part from about 2 to about 80 mole percent glycolide, which process utilizes a combination of a monofunctional polymerization initiator and a di-functional polymerization initiator, to achieve rates of crystallization of the copolymer of at least about 2 times faster than the rate of crystallization of a copolymer made by a similar process utilizing either the mono-functional or the di-functional polymerization initiator alone. Absorbable polylactone copolymers prepared by such processes and medical devices containing such copolymers are also disclosed.

Abstract: The object of the present invention is to provide a novel method for effectively producing a cyclic lactic acid oligomer, and a cyclic lactic acid oligomer produced by the method.

Abstract: Disclosed are fibers and films prepared from polyesters of a dicarboxylic acid, preferably terephthalic acid, and a diol selected from 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, or 1,3-propanediol. The fibers and films contain a multifunctional epoxide additive and, optionally, an antioxidant, and show an increased dry heat stability when exposed to elevated temperatures in the presence of air while preserving excellent hydrolytic stability. Also disclosed is a process for stabilizing polyester fibers by melt blending a polyester and epoxide additive and melt spinning. The fibers and films are particularly useful in applications requiring elevated temperatures.

Abstract: A lactic acid polyester (III), having a lactic acid unit (I) and a polyester unit (II) at a weight ratio within the range of 10:90 to 90:10, a weight average molecular weight of 10,000 or more, and a glass transition temperature of 60° C. or below, imparts superior impact resistance to polyhydroxy carboxylic acids while maintaining superior flexibility and transparency and with minimal occurrence of bleedout.

Abstract: Biodegradable, flowable or flexible polymer compositions are described comprising a polymer having the recurring monomeric units shown in formula I: wherein: each of R and R′ is independently straight or branched alkylene, either unsubstituted or substituted with one or more non-interfering substituents; L is a divalent cycloaliphatic group; R″ is selected from the group consisting of H, alkyl, alkoxy, aryl, aryloxy, heterocyclic or heterocycloxy; and n is 5 to 1,000, wherein said biodegradable polymer is biocompatible before and upon biodegradation. In one embodiment, one or more of R, R′ or R″ is a biologically active substance. Amorphous compositions containing a biologically active substance, in addition to the polymer, and methods for controllably releasing biologically active substances using the compositions, are also described.

Abstract: An absorbable crystalline, monocentric polyaxial copolymer comprising a central carbon or nitrogen atom and at least three axes, each of which includes an amorphous flexible component adjacent and originating from the central atom and a rigid, crystallizable component extending outwardly from the amorphous, flexible component is disclosed along with the use of such copolymer in medical devices which may contain a bioactive agent. The present invention also relates to a suture, stents, stent mantles and sealing devices made from the polyaxial copolymer.

Abstract: The present invention is directed to absorbable polylactone copolymers prepared in part from about 2 to about 80 mole percent glycolide, utilizing a combination of a monofunctional polymerization initiator and a di-functional polymerization initiator, to achieve rates of crystallization of the copolymer of at least about 2 times faster than the rate of crystallization of a copolymer made by a similar process utilizing either the mono-functional or the di-functional polymerization initiator alone. Medical devices containing such copolymers are also disclosed.

Abstract: This invention relates to macromolecule modifiers containing biologically active drugs/biomolecules, or precursors thereof, and fluoroligomers; compositions comprising the macromolecules containing the drugs and fluoroligomers in admixture with polymers, particularly biomedical polymers; articles made from the admixtures, particularly medical devices.

Abstract: This invention provides a hydroxyalkyl(meth)acrylate composition modified by a small amount of lactones in which a proportion of monomers having two or more continuous chains of lactone is less than 50% (area % by GPC). This invention also provides methods for synthesizing such a composition. This invention also provides an acrylic polyol resin comprising the hydroxyalkyl(meth)acrylate composition, a carboxylic group-containing acrylate composition modified by a small amount of lactones, and a polyester unsaturated monomer modified by a small amount of lactones. Uses of these materials in curable resins, coating compositions, and finishing agents are also provided.

Abstract: A process for producing a biodegradable polymer having free carboxyl at the &ohgr;-end charcterized by polymerizing a cyclic ester compound in the presence of a hydroxymonocarboxylic acid derivative having protected carboxyl or a hydroxydicarboxylic acid derivative having protected carboxyl, and then deprotecting the thus obtained polymer having protected carboxyl at the &ohgr;-end. Use of the above process makes it easy to control the molecular weight of the target biodegradable polymer and the content of free carboxyl therein, thereby enabling the efficient production of a polymer having a high purity and being contaminated with littel catalyst remaining therein.

Abstract: The present invention relates in general to implantable, resorbable copolymers containing L-lactide and glycolide repeat units, and in particular to terpolymers containing L-lactide, glycolide, and one other type of repeat unit selected from the group consisting of D-lactide, D,L-lactide, and &egr;-caprolactone. Medical devices for in vivo implantation applications containing such implantable, resorbable copolymers are also described, as well as methods for making such copolymers and devices.

Abstract: The present invention is directed to a method for reducing waste accumulation by using an environmentally degradable disposable material. The disposable material, which includes a hydroxycarboxylic acid-containing polymer, degrades hydrolytically during operative and disposal stages in a controlled manner such that the disposal degradation rate of the material is accelerated relative to the operative degradation rate of the material.

Abstract: Polyester resins formed by recurring units X=[O—(CH2)n—OCO—(CH2)m—CO] and/or Y=[O—(CH2)k—CO], where the half-sum of n+m is equal to or greater than 6 and k is a number equal to or greater than 6, or by copolymers comprising units and/or sequences having the formula xi[O—(CH2)ni—OCO—(CH2)mi—CO]; yj[O—(CH2)kj—CO] where: i,j=1-5; ni=2-22; mi=0-20; kj=1=21; (Formula (1)) and xi and yj vary between 0 and 1 and are molar fractions of the various units such that (Formula (2)), are used for the preparation of products in which a permeability to water vapour of less than 350 g×30 &mgr;m/m2 per day, measured at 38° C. and 90% RH and good biodegradability are required.

Abstract: An object is to provide a biaxially stretched film which allows tacking, is heat-stickable, is less liable to unevenness in thickness, breakage, whitening, unevenness, etc. i.e. has stretching stability and is decomposable in the natural environment. It comprises a polylactic acid-family polymer as its major component, and has a storage elastic modulus E′ at 120° C. of 100-230 MPa as measured using a test method concerning temperature dependency of the dynamic viscous elasticity under JIS K7198.

Abstract: The invention relates to a coating material for medical treatment, particularly a wound contact material, of resorbable, synthetic material, which is formed from a terpolymer based on lactide, trimethylene carbonate and &egr;-caprolactone with a maximum lactide content of 85 wt. %, trimethylene carbonate in the range 5 to 20 wt. % and &egr;-caprolactone in the range 5 to 20 wt. %, a method for its manufacture and its use.

Abstract: Copolymers of lactide and glycolide with high glycolide content. The average glycolate block length is less then about 3, which allows the copolymer to be soluble in slightly polar solvents such as methylene chloride.

Abstract: The present invention is directed to a process for making an absorbable polylactone copolymer prepared in part from about 2 to about 80 mole percent glycolide, which process utilizes a combination of a monofunctional polymerization initiator and a di-functional polymerization initiator, to achieve rates of crystallization of the copolymer of at least about 2 times faster than the rate of crystallization of a copolymer made by a similar process utilizing either the mono-functional or the di-functional polymerization initiator alone. Absorbable polylactone copolymers prepared by such processes and medical devices containing such copolymers are also disclosed.

Abstract: Polylactic acid is produced from dimers of lactic acid in an energy saving manner by contacting a lactic acid source via an extraction membrane with an amine carrier solvent to extract lactic acid across the membrane. One or two membranes may be used. After extraction, the aminium lactate salt is crystallized, disassociated and purified.

Abstract: A polymerisation process for the preparation of vinylic polymers from the corresponding vinylic monomers which process comprises the step of reacting a vinylic monomer in the presence of a catalyst system comprising a) a metal complex of general formula (I) where A is selected from the group consisting of nickel, iron, cobalt, chromium, manganese, titanium, zirconium, vanadium and the rare earth metals; L1, L2, L3 and L4 are ligands and b) a Lewis acid of general formula (II) wherein at least one of W, Y or Z is capable of forming a co-ordination bond with A and the others of W, Y and Z are bulky groups; D is selected from the group consisting of aluminium, magnesium, zinc and boron.

Abstract: A film of the present invention includes, as its main component, an aliphatic polyester whose primary repeating unit is represented by a general formula —O—CHR—CO— (where R denotes H or an alkyl group having a carbon number of 1-3). A three-dimensional surface roughness SRa of at least one side of the film is about 0.01 &mgr;m to about 0.1 &mgr;m. PCC value denoting the number of projections on the film per a unit of area along a mean roughness plane and the three-dimensional surface roughness SRa satisfy the following relationship: PCC value≦7000-45000×SRa.

Abstract: This invention is directed to a coating composition used for original equipment manufacturing or refinishing uses in the automotive industry, which coating composition utilizes an acrylic polymer which contains substituted or unsubstituted exomethylene lactones or lactams as a comonomer.

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.

Abstract: A stereospecific poly(lactic acid) is isotactic poly(lactic acid) having a number average molecular weight ranging from 10,000 to 200,000 grams per mole, with, on average, an equal number of poly (R) and poly (S) blocks where each block contains an average of 5 to 50 monomer units. Product was prepared by polymerizing rac-lactide in the presence of racemic catalyst consisting of: and the corresponding S-enantiomer or in the presence of racemic catalyst consisting of: and the corresponding S-enantiomer, wherein R is C1-C4 alkyl which is straight chain or branched.

Abstract: An absorbable crystalline, monocentric polyaxial copolymer comprising a central carbon or nitrogen atom and at least three axes, each of which includes an amorphous flexible component adjacent and originating from the central atom and a rigid, crystallizable component extending outwardly from the amorphous, flexible component is disclosed along with the use of such copolymer in medical devices which may contain a bioactive agent.

Abstract: The present invention is directed to a method for reducing waste accumulation by using an environmentally degradable disposable material. The disposable material, which includes a hydroxycarboxylic acid-containing polymer, degrades hydrolytically during operative and disposal stages in a controlled manner such that the disposal degradation rate of the material is accelerated relative to the operative degradation rate of the material.

Abstract: The present invention includes photocurable, liquid polymers incorporating coumarin ester endgroups into their molecular structure, which polymers are crosslinked upon irradiation with ultraviolet light by photochemically allowed [2+2] cycloaddition reactions among the chain ends, and which crosslinked polymers are useful in the preparation of medical devices, tissue engineering scaffolds, drug delivery systems and, in particular, in vivo preparation of implants in an open surgical procedure or laproscopically.

Abstract: High molecular weight copolyesters have been prepared from macrocyclic oligoesters and cyclic esters in the presence of a transesterification catalyst. The invention generally features a method of making a copolyester, a method of making a block copolymer of copolyester, and a copolyester prepared from macrocyclic oligoesters and cyclic esters.

Abstract: Polymerization of &agr;-bromomethyl-&agr;-methyl-&bgr;-propiolactone (BMMPL) or &agr;-chloromethyl-&agr;-methyl-&bgr;-propiolactone (CMMPL) yielded thermoplastic homopolymers that upon azidation led to a novel energetic thermoplastic polyester: poly(&agr;-azidomethyl-&agr;-methyl-&bgr;-propiolactone) (PAMMPL). An energetic copolyether-ester thermoplastic elastomer was prepared by using glycidyl azide polymer, a dihydroxyl terminated energetic polymer, as a macroinitiator for the polymerization of BMMPL or CMMPL. The azidation of the resulting copolyether-ester yielded an energetic thermoplastic elastomer that melted at between 80° C. and 85° C. Polymerization of &agr;-dibromomethyl-&bgr;-propiolactone (DBMPL) resulted in a polymer which upon azidation yielded a new energetic polymer that can be used as a binder or into an energetic thermoplastic elastomer synthesis.

Abstract: Copolymers of lactide and glycolide with high glycolide content. The average glycolate block length is less then about 3, which allows the copolymer to be soluble in slightly polar solvents such as methylene chloride.

Abstract: Biodegradable, flowable or flexible polymer compositions are described comprising a polymer having the recurring monomeric units shown in formula I: wherein: each of R and R′ is independently straight or branched alkylene, either unsubstituted or substituted with one or more non-interfering substituents; L is a divalent cycloaliphatic group; R″ is selected from the group consisting of H, alkyl, alkoxy, aryl, aryloxy, heterocyclic or heterocycloxy; and n is 5 to 1,000, wherein said biodegradable polymer is biocompatible before and upon biodegradation. In one embodiment, one or more of R, R′ or R″ is a biologically active substance. Amorphous compositions containing a biologically active substance, in addition to the polymer, and methods for controllably releasing biologically active substances using the compositions, are also described.

Abstract: An article having a non-thrombogenic surface and a process for making the article are disclosed. The article is formed by (i) coating a polymeric substrate with a crosslinked chemical combination of a polymer having at least two amino substituted side chains, a crosslinking agent containing at least two crosslinking functional groups which react with amino groups on the polymer, and a linking agent containing a first functional group which reacts with a third functional group of the crosslinking agent, and (ii) contacting the coating on the substrate with an antithrombogenic agent which covalently bonds to a second functional group of the linking agent. In one example embodiment, the polymer is a polyamide having amino substituted alkyl chains on one side of the polyamide backbone, the crosslinking agent is a phosphine having the general formula (A)3P wherein A is hydroxyalkyl, the linking agent is a polyhydrazide and the antithrombogenic agent is heparin.

Abstract: This invention relates to a method of polymerization of lactide or glycolide (GA) monomers and in particular to a method of polymerizing one type of the monomers or two types of the monomers using alkyl aluminum catalyst to proceed with bulk or solution polymerization to prepare biodegradable homopolymers or copolymers, and high-molecular-weight homopolymers of polylactide (PLA), polyglycolide (PGA), or copolymers of lactide/glycolide prepared thereof.

Abstract: The invention relates to a lactic acid residue containing polymer composition and product having improved stability and to methods for the preparation and use thereof. The lactic acid residue containing polymer preferably includes a polylactide polymer having a number average molecular weight of between about 25,000 and about 200,000, lactide, if present at all, present in a concentration of less than 0.5 wt % based on the weight of the composition, and deactivating agents. Articles which can be manufactured from the lactic acid residue containing polymer composition include fibers, coated paper, films, moldings, and foam.

Abstract: The present inventors has its objects to provide a polymerization catalyst component, a copper compound which can easily be synthesized and is stable.

Abstract: This invention is directed to a coating composition used for original equipment manufacturing or refinishing uses in the automotive industry, which coating composition utilizes an acrylic polymer which contains substituted or unsubstituted exomethylene lactones or lactams as a comonomer.

Abstract: The invention relates to a composition based on a grafted metal oxide, its preparation and its use in a process of polymerization by opening oxygenated rings such as alkyl oxides, cyclic esters or cyclic carbonates. The composition comprises a support chosen from the group of metal oxides capable of containing hydroxyl functions, onto which is grafted a group of formula (1) —M(OR)n in which M is an element chosen from scandium, zirconium, hafnium, niobium, tantalum, rare-earth metals and actinides, R is an organic group and n is an integer greater than or equal to 1. The composition is prepared by forming a suspension of the abovementioned support and then placing in contact and reacting this suspension with a compound of formula (2) M(OR)n+1 in which M, R and n are defined as above.

Abstract: An aliphatic polyester film comprising, as a main component, a polylactic acid having a reduced viscosity (&eegr;sp/C) of not less than 0.50 dl/g and not more than 2.50 dl/g, wherein the film has a thermal shrinkage in the longitudinal direction at 120° C. of not more than 5.0% is provided. The aliphatic polyester film of the present invention is provided which is useful as a packaging film and an adhesive tape, superior in hand tearability, twist retention, processability and film forming property, and which is biodegradable when placed in a natural environment.

Abstract: Isotactic poly ((R)-lactic acid) or isotactic poly (S)-lactic acid are respectively prepared from (R,R)-lactide and (S,S)-lactide using a catalyst which has a zinc center or a magnesium center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group. Heterotactic poly(lactic acid) is prepared from rac-lactide using a catalyst which has a zinc center and two ligands where one of the ligands is a propagating group and the other of the ligands is not a propagating group; heterotactic poly(lactic acid) is a novel composition. The catalyst with a magnesium center is a novel catalyst.

Abstract: Novel compounds having one group 13 element bound with one mono- or di-anionic tridentate ligand, a method of preparation thereof and use thereof as a copolymerization catalyst.

Abstract: Synthetic absorbable medical devices made totally or in part from a random polymer comprising glycolide, lactide, trimethylene carbonate, and caprolactone are provided. The polymer can be fabricated into a monofilament which exhibits physical characteristics equivalent to or superior than gut sutures.

Abstract: The present invention provides a process for preparing biodegradable aliphatic polyester grafted with polyether which comprises a step of ring opening polymerization of a hydrophilic monomer of epoxide-substituted ethyleneglycolmethylether oligomer or ethyleneglycol oligomer, and a biocompatible cyclic monomer forming polymer backbone with the said monomer, and a non-toxic biodegradable polymer prepared therefrom. In accordance with the invention, the graft ratio and molecular weight of polyether in the biodegradable aliphatic polyester can be easily controlled, and the hydrophlicity and crystallinity are also regulated thereby. The biodegradable polymer of the invention has features of minimized protein adhesion and superior softness, due to its hydrophilic side-chain. Accordingly, it can be applied as biomedical polymers such as the matrices for drug delivery system, suture thread, or bioabsorbable and water-soluble polymers.

Abstract: A 2-oxetanone sizing agent that is made from fatty acid(s) containing linoleic acid. Paper that is sized with the 2-oxetanone alkaline sizing agent does not encounter machine feed problems in high speed converting or reprographic machines, so the sizing agent is useful for paper including continuous forms bond paper and adding machine paper, processes for converting the paper into envelopes, continuous forms bond paper and adding machine paper.

Abstract: Disclosed are a novel polylactone having amino groups and to a process for the preparation thereof. The polylactone having amino groups of the present invention is excellent in color hue, and it can be preferably employed in fields such as coatings, inks, ultraviolet ray curable or electronic beam curable resins, etc., in which the color hue becomes a serious problem. Furthermore, disclosed are a novel compound having amino groups and to a process for the preparation thereof. The compound having amino groups of the present invention can be preferably employed as a dispersant for pigments in a coating composition or a printing ink composition.