Abstract: A surgical stapler end effector comprises a staple cartridge, an anvil, and a buttress assembly. The staple cartridge comprises a plurality of staples and a deck. The staple cartridge is operable to drive the staples through the deck. The anvil is movable from an open position toward the staple cartridge to reach a closed position. The anvil includes an underside having staple forming surface configured to receive staples driven through the deck. The buttress assembly comprises a buttress body and an adhesive material. The adhesive material comprises a polymer. The polymer is bioabsorbable. The polymer has an inherent viscosity at or below 3.0 dL/g.

Abstract: The present invention discloses new catalyst systems based on complexes of divalent metals supported by chelating phenoxy ligands for immortal ring-opening polymerisation of cyclic esters and cyclic carbonates.

Abstract: The invention provides a metal alkoxide complex of Formula (I), wherein X, M, R1, R2, R3, m, n, y and z are as defined in the Description. The invention also provides a catalyst composition comprising the metal alkoxide complex and a hydroxy-containing compound, wherein the molar ratio of the metal alkoxide complex to the hydroxy-containing compound is 1:01-1000. The invention also provides a production method of poly-?- caprolactone or polyactide, wherein an ?-caprolactone monomer or a lactide monomer is reacted in the presence of the metal alkoxide complex or catalyst composition to obtain poly-?-caprolactone or polylactide. The metal alkoxide complex and the catalyst composition thereof can be used to catalyze the synthesis of poly-?- caprolactone or polylactide with a high efficiency.

Abstract: A composition which comprises polylactide and has excellent heat stability, color and hydrolytic resistance. The composition comprises (i) polylactide, (ii) a metal catalyst and (iii) a hypophosphorous acid-based deactivator or a metaphosphoric acid-based deactivator.

Abstract: To provide a process for producing BPDA whereby high productivity is attained while high purity is maintained. A process for producing biphenyltetracarboxylic acid dianhydride, which comprises heating biphenyltetracarboxylic acid to produce biphenyltetracarboxylic acid dianhydride, characterized in that the heating is carried out at a pressure of from 1×102 Pa to 1.1×105 Pa to a maximum temperature in a range of from 210° C. to 250° C. in such a manner that the temperature rising rate is higher than 50° C./hr for a period of at least ¼ of the time for the temperature rise from 60° C. to 210° C., and the temperature is maintained to be from 150° C. to 250° C. for from 0.5 to 10 hours.

Abstract: The present invention relates to a novel carbohydrate lactone, functionalized aliphatic polyesters and copolymers formed therefrom, and processes for the preparation thereof from renewable resources.

Abstract: Copolymers exhibiting the following combinations of properties, including without limitation, ?-caprolactone in an amount ranging from about 12 to about 70 mole percent, glycolide in an amount ranging from about 30 to about 88 mole percent, crystallinity ranging from about 10 to about 50% as measured by WAXD or about 10 to about 50 J/g as measured by DSC, and an inherent viscosity ranging from about 0.5 to about 1.45 dL/g as measured in a 0.1 g/dl solution of HFIP at 25° C.; a method for melt blowing such copolymers and nonwoven constructs produced therefrom are described herein.

Abstract: Provided is a method for producing polylactic acid comprising the step of a ring-opening polymerization of lactide in the presence of an alkylaluminum compound represented by the following formula (1): R1nAlX3-n??Formula (1) (wherein n represents an integer of 1 to 3; R1 may be the same or different and independently represents a linear or branched alkyl group having 1 to 10 carbon atoms; X may be the same or different and independently represents a halogen atom or a hydrogen atom; and Al represents an aluminum atom) as a ring-opening polymerization catalyst. The ring-opening polymerization of lactide further effectively proceeds in the presence of at least one kind of metal compounds selected from the group consisting of aluminum compounds (except the alkylaluminum compounds represented by the above formula (1)), zinc compounds, titanium compounds, zirconium compounds, magnesium compounds, and calcium compounds.

Abstract: The invention concerns a process for preparing a block or comb copolymer comprising at least one hydrophilic portion and at least two hydrophobic portions, by anionic solvent-free polymerization of a prepolymer selected from a polyethylene glycol and a polyvinyl alcohol, and of a lactone or dilactone monomer. The process is carried out in the presence of an alkaline-earth metal hydride, in an inert atmosphere, and the polymerization step is not carried out under vacuum. The invention also concerns copolymers obtained by this process.

Abstract: To provide a process for producing a polyester ether poly- or mono-ol having a narrow molecular weight distribution, which is obtained by copolymerizing an initiator having hydroxyl groups with a cyclic ester compound and an alkylene oxide. It is possible to produce a polyester ether poly- or mono-ol having a molecular distribution (Mw/Mn) of from 1.02 to 1.4 by copolymerizing a cyclic ester compound which carbon number is from 3 to 9 and an alkylene oxide which carbon number is from 2 to 20 with an initiator having from 1 to 12 hydroxyl groups and having a number average molecular weight (Mn) of from 18 to 20,000 in the presence of a double-metal cyanide complex catalyst is having tert-butyl alcohol as at least a part of an organic ligand.

Abstract: Processes for feeding catalyst systems to a melt phase process for the manufacture of polyester polymers, and more particularly, to split catalyst solution feeds to the melt phase process to provide the target amount and ratio of catalyst metals.

Abstract: The present invention mainly relates to a carbon-carbon bond formation catalyzed by a complex comprising a novel and stable ligand and a metal center. The ligand uses a ring, particularly a phenyl group, or a hydrocarbon group to link an amino group and PR1R2, NR1R2, OR1, SR1, or AsR1R2 group for stabling the structure of the ligand.

Abstract: A polyamic ester (PAE) film, which shows an electro-optic (EO) and nonlinear optical (NLO) properties without a poling process, is prepared. The chromophore in the film seems to be slightly oriented normally to the film surface (transverse magnetic field (TM) direction even though the polymer solution is spin-coated. This is due to the nano-configuration structure of PAE controlled by introducing a designed chemical structure into the monomeric repeating unit of PAE. Manufacturing the relating devices can be simplified by using the self-poled polymer film as a polymer waveguide. Additionally, the EO property of the film is thermodynamically stable.

Abstract: A composition for use as a polymer electrolyte, wherein said composition includes one or more polar materials and one or more polyesters of formula III, wherein each unit A may be identical or different and is of the structure IV, wherein each unit B may be identical or different and is of the structure V, wherein R and R1 are each, independently, hydrogen, optionally substituted hydrocarbyl or an inert functional group; a process for preparing said composition; the use of said composition as a polymer electrolyte in coulometers, displays, smart windows, cells or batteries; and a cell and/or battery having said composition.

Abstract: The present invention provides a biaxially oriented film of a polylactic acid resin that is suitable for films for bags and packaging films for various windows, particularly films for outlook window envelopes. The film is biodegradable and, as films for outlook window envelopes, is superior in the coating adaptability for an antistatic agent, a lubricant and an antiblocking agent or the like and in the high-speed cutting property. The present invention discloses a biaxially oriented film of a polylactic acid resin comprising not less than 50% by weight of a polylactic acid resin, which has a storage modulus E?at 80° C. within the range from 10 MPa to 3,000 MPa, as determined by the test method for temperature dependency of dynamic viscoelasticity, in accordance with JIS K7198 (method A); a heat shrinkage of not higher than 10%, upon heating at 80° C. for 10 seconds; and a tear strength in the width direction (TD direction) of the film of 10 to 200 mN, as determined in accordance with JIS K7128 (method B).

Abstract: A block copolymer is disclosed, which comprises a first block comprising polymerized units of an alkylene oxide and a second block comprising polymerized units of an alkylene oxide and a lactone, said copolymer being obtainable by polymerizing an alkylene oxide in the presence of an organic initiator to form said first block, and reacting the first block with a mixture of an alkylene oxide and a lactone. Such copolymers are found to have improved foam inhibition characteristics while maintaining their biodegradable properties.

Abstract: The invention relates to a polymer material having electro optic and nonlinear optical properties suitable for manufacturing a device using the electro optic and nonlinear optical properties. More particularly, the present invention relates to a polymer material having excellent electro optic properties and optical nonlinearities, maintaining the properties under the manufacturing conditions of high temperature, and having physical, chemical, and optical stabilities by introducing an organic chromophore as a side chain of the polymer so that the polymer material can be suitable for manufacturing an electro optic and nonlinear optical device, to a film manufactured from the polymer material, and to a method of manufacturing the polymer material.

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 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: The present invention uses a reactor that combines devices having a special portion structure to solve the difficulty of uniform blending due to the reactants becoming highly viscous, the difficulty of heat removal, and the increase in pressure loss, thus leading to continuous production of a polyester-based polymer stably having excellent quality.

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 generally directed to a process for producing lactide-based polymers and the polymers produced by this process. The polymers of the present invention are terpolymers formed by the copolymerization of a lactide monomer, a linking monomer and an epoxy-terminated monomer. In one embodiment of the invention, the polymers may be formed from fluorine-containing monomers or aromatic ring-containing monomers. The disclosed materials may display improved hydrolytic and thermal characteristics as compared to previously known lactide-based materials. For example, the lactide based terpolymers may have a glass transition temperature over 60° C. For instance, lactide-based thermoplastic terpolymers of the present invention can have a glass transition temperatures of about 80° C. or higher. Lactide-based thermoset networks of the invention can have glass transition temperatures of up to about 200° C.

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: 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: 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: The present invention provides a method for producing highly purified polyhydroxyalkanoate (PHA) with high yield, by removing cell components other than PHA from cells containing PHA. Moreover, the present invention provides a method for simply removing or reducing chlorine remained in the collected PHA particles, when a treatment with an oxidizing agent containing hypochlorite is performed in the production of PHA as described above. One of the above-described methods comprises a step of treating cells containing polyhydroxyalkanoate with an oxidizing agent containing at least hypochlorite, a step of separating the treated cells into a water-soluble fraction and a water-insoluble fraction, and a step of reducing chlorine remained in the water-insoluble fraction. The step of reducing chlorine may be a step of washing the water-insoluble fraction with a hot water, thiosulfate solution or polar solvent solution containing at least an organic polar solvent in which polyhydroxyalkanoate is insoluble.

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: 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: 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: 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 invention relates to polycondensation resins which are prepared by polycondensation of compounds having a low molecular weight and separation of small molecules in the presence of at least one hetergeneous catalyst. The invention also relates to polyaddition resins which are prepared by polyaddition in the presence of at least one heterogeneous catalyst. The invention further relates to the use of said polycondensation resins and polyaddition resins for the preparation of moulded parts, adhesives and coating materials.

Abstract: A method of making telechelic oligomers comprises reacting a substrate compound selected from the group consisting of relatively high molecular weight polymers with a chain transfer agent in the presence of an alkali metal catalyst. The telechelic oligomers thus produced may then be reacted with monomers according to known polymerization techniques in order to produce block copolymers.

Abstract: A bromine-containing, hydroxy-functional copolymer is prepared from an initiator that is solid at room temperature and has at least one bromone atom. The initiator is reacted with an effective amount of lactone monomers, optionally in the presence of a catalyst, to establish a bromine-containing, hydroxy-functional copolymer that is a liquid at room temperature. The copolymer of this invention may be used as liquid reactive flame retardant and, in the event the copolymer is polyfunctional, as a crosslinker.

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: 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: 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: Condensation copolymers are disclosed which are polymerized from a first monomer which is capable of polymerization by condensation polymerization, e.g., ring opening lactone polymerization, and a second monomer which is effective to suppress the crystallization of the copolymer. It is disclosed that suppression of the crystallization can provide enhanced mechanical properties in films made from the copolymers. As a result, films prepared from the copolymers of the present invention can have properties rendering them suitable for use as biodegradable trash bags as well as for other uses.

Abstract: Copolyesters are prepared using cyclic esters or carbonates as monomers and a metallic salt of the formula Me2+X2 as catalyst. Me2+ represents Ca, Fe(II), Mg, Mn(II) or Zn, and X is an anion of an aminocarboxylic acid, hydroxycarboxylic acid or a halide. Monomer and catalyst are used in a monomer/catalyst ratio of greater than 100.

Abstract: Methods are provided for separating polyhydroxyalkanoates ("PHAs") from plants, such as transgenic oil crop plants. The methods advantageously permit both the oil and the PHAs to be recovered from the plant biomass. To isolate the PHAs, in one embodiment, a biomass derived from an oil crop plant is pre-processed, for example by grinding, crushing or rolling. The oil then is extracted from the biomass with a first solvent in which the oil is soluble and in which the PHAs are not highly soluble to remove the oil. The biomass then can be extracted with a second solvent in which the PHA is soluble, to separate the PHA from the biomass. Alternatively, the PHA-containing biomass is treated with a chemical or biochemical agent, such as an enzyme, to chemically transform the PHA into a PHA derivative. The PHA derivative then is separated from the mixture using, for example, a physical separation process such as distillation, extraction or chromatography.

Abstract: A bulk extrusion polymerization process to derive an aliphatic polyester from a suitable ester monomer, preferably .epsilon.-caprolactone. Novel reaction formulations containing less than 100 ppm water and having an acid value less than 0.5 mg KOH/g and preferably less than 0.2 mg KOH/g enable the polymerization of bulk monomer in an extruder in a resident time of less than 2 minutes. Different catalyst and initiator systems, processing protocols, and screw configurations lead to the preferred manufacture of poly(.epsilon.-caprolactone) polymer of number average molecular weight, M.sub.n, greater than 100,000. A novel poly(.epsilon.-caprolactone) intermediate optionally grafted to starch, is described which has significantly different processing and use characteristics as compared to a straight-chain polycaprolactone.

Abstract: A hydroxyalkanoic acid (PHA)is recovered from matter derived from living organisms by dissolving the PHA in a solvent which is a lower ketone, dialkyl ether or a lower alcohol or a monocarboxylic acid ester thereof, separating the solution from such matter and recovering PHA from the solution.

Abstract: The polymerization reaction is conducted by heating a lactide, a cyclic imide compound (e.g. succinimide, etc.) and a polymerization catalyst (e.g. tin octylate, etc.) at 100-190.degree. C. with stirring under a nitrogen gas flow. It is preferred that an amount of the cyclic imide compound is from 1 to 35% by mole based on the lactide. Even if an amount of the polymerization catalyst is small, e.g. 0.00001-0.1 mole %, based on the lactide, polylactic acid can be efficiently prepared. It is possible to avoid remains of the catalyst in the polymer and coloring of the polymer.

Abstract: A bulk extrusion polymerization process to derive an aliphatic polyester from a suitable ester monomer, preferably .epsilon.-caprolactone. Novel reaction formulations containing less than 100 ppm water and having an acid value less than 0.5 mg KOH/g and preferably less than 0.2 mg KOH/g enable the polymerization of bulk monomer in an extruder in a resident time of less than 2 minutes. Different catalyst and initiator systems, processing protocols, and screw configurations lead to the preferred manufacture of poly(.epsilon.-caprolactone) polymer of number average molecular weight, M.sub.n, greater than 100,000. A novel poly(.epsilon.-caprolactone) intermediate optionally grafted to starch, is described which has significantly different processing and use characteristics as compared to a straight-chain polycaprolactone.

Abstract: Absorbable/resorbable mixtures of aliphatic polyesters of poly(lactide), poly(glycolide), poly(trimethylene carbonate), poly(p-dioxanone) and poly(.epsilon.-caprolactone) and calcium containing bone regenerating compounds such as powdered, non-fibrous calcium phosphates are described. The composites when used to manufacture medical devices exhibit improved absorption characteristics and other physical properties.

Abstract: Absorbable/resorbable mixtures of aliphatic polyesters of poly(lactide), poly(glycolide), poly(trimethylene carbonate), poly(p-dioxanone) and poly(.epsilon.-caprolactone) and calcium containing bone regenerating compounds such as powdered, non-fibrous calcium phosphates are described. The composites when used to manufacture medical devices exhibit improved absorption characteristics and other physical properties.

Abstract: Polymer compositions are provided which comprise a first polyhydroxyalkanoate component and optionally a second polymer component, the composition have enhanced properties by using an inorganic oxygen containing compound in the composition. The inorganic oxygen containing compound may be acting as a transesterification catalyst.

Abstract: The invention relates to a substantially solventless curable resin composition, in particular for the fabrication of prepregs, which contains more than 45% by weight of substances which are solid at ambient temperature at least or at lower temperature, and which, in addition to comprising customary modifiers, comprises solid epoxy resins or a mixture of liquid and solid epoxy resins, at least one initiator which is sensitive to UV radiation for the polymerisation of the epoxy resins and has the formula I ##STR1## wherein a and b are each independently of the other 1 or 2, R.sup.1 ist a .pi.-arene, R.sup.2 is a .pi.-arene, an indenyl anion or a cyclopentadienyl anion, [X].sup..crclbar. is an anion [LQ.sub.m ].sup..crclbar.

Abstract: The biodegradability of polyglycol-based block copolymers is improved by including in the copolymer a lactone. Representative of these biodegradable enhanced copolymers are those made of 1,2-butylene oxide and .epsilon.-caprolactone capped with a homopolymer block of ethylene oxide. The copolymers of this invention have many uses, such as nonionic surfactants, foam control agents, lubricants, and the like.