1387 results about "Ultrahigh molecular weight polyethylene" patented technology

A high strength abrasion resistant surgical suture material with improved tie down characteristics and enhanced tissue remodeling and biocompatibility includes protein polymer fibers blended with synthetic fibers. The suture features a multifilament cover formed of strands of ultra high molecular weight long chain polyethylene braided with polyester, nylon or other nonabsorbable materials, along with fibers of a protein polymer, such as collagen. The cover surrounds a core formed of twisted strands of ultrahigh molecular weight polyethylene. The core also can include collagen fibers. The suture, provided in a #2 size, has the strength of #5 Ethibond, is ideally suited for most orthopedic procedures, and can be attached to a suture anchor or a curved needle. The collagen fiber enhances tissue remodeling into the suture strand, thus improving biocompatibility.

A high strength surgical suture formed of ultrahigh molecular weight polyethylene (UHMWPE) yarns, the suture being coated with native or denatured collagen. The braided jacket surrounds a core formed of twisted yarns of ultrahigh molecular weight polyethylene. The suture has exceptional strength, is ideally suited for most orthopedic procedures, and can be attached to a suture anchor or a curved needle.

The invention provides a medical implant or medical implant part comprising a body and a surface layer, wherein the surface layer comprises a mixture comprising at least one hydrophilic polymer and ultrahigh molecular weight polyethylene having a weight average molecular weight of about 400,000 atomic mass units or more. The invention also provides a method for producing such a medical implant or medical implant.

The abrasion resistance of organic fiber based ropes and cords is increased by a outer woven cover of tapes of high molecular weight and more preferably ultrahigh molecular weight polyethylene

In one embodiment, the present invention is a braided filament including a plurality of strands each having at least one ultrahigh molecular weight polyethylene fiber and at least one polyester fiber wherein the quantity of certain types of fibers in a first strand is the same as the quantity of the same type of fibers in a second strand. In a variant, one additional strand of the braided filament is a monofilament strand. In another variant, each strand is homogeneous with respect to the other strands and is made exclusively from ultrahigh molecular weight polyethylene fibers and polyester fibers such that each strand has the same distribution and quantity of fiber types.

The invention provides a process for quenching free radicals present in irradiated ultrahigh molecular weight polyethylene comprising the steps of (a) providing a mass of irradiated ultrahigh molecular weight polyethylene, wherein the mass comprises free radicals, (b) immersing at least a portion of the mass of irradiated ultrahigh molecular weight polyethylene in a non-polar solvent having a temperature for a time and under conditions sufficient to quench a substantial portion of the free radicals contained therein, wherein the temperature of the non-polar solvent is maintained below the melting point of the ultrahigh molecular weight polyethylene, (c) removing the mass of irradiated ultrahigh molecular weight polyethylene from the non-polar solvent, and (d) removing any non-polar solvent from the mass of irradiated ultrahigh molecular weight polyethylene.

The invention discloses an ultrahigh molecular weight polyethylene/graphene composite fiber and a preparation method as well as application thereof. The composite fiber consists of ultrahigh molecular weight polyethylene (UHMWPE) and graphene; the weight-average molecular weight of the ultrahigh molecular weight polyethylene is 1*10<6>-4*10<6>, particularly 1*10<6>-3*10<6>; the diameter of the graphene is 0.6-1.8 mum; and the thickness of the graphene is 0.5-5 nm. The graphene is a material which has the maximum strength in the world up to now. According to the invention, the graphene powder is introduced into the ultrahigh molecular weight polyethylene fiber, so that the ultrahigh molecular weight polyethylene/graphene composite fiber has excellent mechanical property. Preliminary research shows that the tensile strength of the ultrahigh molecular weight polyethylene/graphene composite fiber prepared by the method can reach 2.5 GPa, the tensile modulus is 130 GPa, and the thermal decomposition temperature in nitrogen gas can reach up to over 390 DEG C.

A family of selectively absorbable/biodegradable, fibrous composite constructs includes different combinations of biostable and absorbable/biodegradable yarns assembled as initially interdependent, load-bearing components, transitioning to exhibit independent functional properties during in vivo end-use. The family of constructs consists of two groups, one group is made of fiber-reinforced composites of high compliance, absorbable matrices of segmented polyaxial copolyesters reinforced with multifilament yarn constructs, which are combinations of ultrahigh molecular weight polyethylene fibers and at least one absorbable/biodegradable fiber selected from silk fibers and multifilament yarns made from linear segmented, l-lactide copolyesters and poly (3-hydroxyalkanoates, are useful in orthopedic, maxillofacial, urological, vascular, hernial repair and tissue engineering applications. The second group is made of coated and uncoated, warp-knitted mesh constructs for use in hernial, vascular, and urological tissue repair and tissue engineering.

The invention relates to a method for preparing a conductive ultrahigh molecular weight polyethylene fiber. The conventional method is complicated in process and causes environmental pollution. The method comprises the following steps of: firstly, immersing the ultrahigh molecular weight polyethylene fiber into acetone, ethanol or a tetrahydrofuran solution, performing ultrasonic washing on the fiber and airing; secondly, dissolving a dopamine substance into a buffer solution to prepare an activation solution, placing the ultrahigh molecular weight polyethylene fiber into the activation solution and activating the ultrahigh molecular weight polyethylene fiber under stirring; and finally, immersing the activated ultrahigh molecular weight polyethylene fiber in a plating solution at temperature of 10 to 60 DEG C for 0.5 to 10 hours so as to finish silver plating. By the method, the surface of the ultrahigh molecular weight polyethylene fiber is activated by using dopamine polymer and metallized by using chemical plating, so that the ultrahigh molecular weight polyethylene fiber with extremely high conductivity can be obtained; and the whole process is environment-friendly and pollution-free.

A removable denture includes a denture base that is made of ultrahigh molecular weight polyethylene and is formed in a predetermined shape by a molded object of ultrahigh molecular weight polyethylene being cut; and artificial teeth that are arrayed at the denture base.

A high strength abrasion resistant surgical suture material with improved tie down characteristics and tissue compliance with braided yarns formed of ether-ketone variant. The suture features a multifilament jacket formed of braided yarns of ether-ketone variant, optionally braided with yarns of polyester, silk, nylon, ultrahigh molecular weight polyethylene or aramid fibers. The braided jacket surrounds a core formed of twisted yarns of ether-ketone variant or ultrahigh molecular weight polyethylene. The suture has exceptional strength, is ideally suited for most orthopedic procedures, and can be attached to a suture anchor or a curved needle.

The invention discloses a rotational molding wear-resistant polyolefin resin and a preparation method thereof. In the rotational molding wear-resistant polyolefin resin, raw materials commonly used in the rotational molding process, namely linear low-density polyethylene, high-density polyethylene or polypropylene is taken as a matrix material; and by adding components of an inorganic filler, ultrahigh molecular weight polyethylene and a lubricant, the wear resistance of the matrix resin is improved. The rotational molding wear-resistant polyolefin resin consists of the following components in percentage by mass: 70 to 80 percent of matrix resin, 10 to 15 percent of inorganic filler subjected to surface treatment, 4 to 13 percent of ultrahigh molecular weight polyethylene and 1.5 to 2 percent of lubricant, wherein the matrix resin is the linear low-density polyethylene, the high-density polyethylene or the polypropylene; and a range of a melt flow rate of the matrix resin is between 2g/10min and 15g/10min.

The present invention relates to a sole material, in particular it is a thermoplastic rubber sole material to which a high-molecular wear-resisting modifier ultrahigh molecular weight polyethylene is added, its composition comprises SBS, PS, filler, softening oil, UHMWPE, demoulding agent, antioxidant, thermal stabilizing agent, light stabilizer and foaming agent. On the basis of SBS, PS, softening oil, filler and colour powder a high-molecular wear-resisting modifier ultrahigh molecular weight polyethylene (UHMWPE) is added, its molecular chain has carbon-carbon long-chain structure, and its number-average molecular weight is 1000000-8000000. In the mixture formula other components and contents are regulated, so that the abrasion-resistance of the sole can be greatly raised (the length of abrasive crack is less than 7 mm).

The invention discloses a wear-resistant and high-toughness polyphenylene sulfide composite material and a preparation method thereof. The composite material is composed of the following components of, by weight, 30-75 parts of polyphenylene sulfide, 20-50 parts of glass fibre, 5-20 parts of carbon fiber, 5-30 parts of a toughening agent, 0-20 parts of polytetrafluoroethylene, 0-20 parts of an ultrahigh molecular weight polyethylene, 2-10 parts of molybdenum disulfide, 0.2-1.5 parts of a coupling agent, 0.2-1 part of an antioxidant, 0.1-0.5 part of a light stability agent and 0.2-2 parts of a processing auxiliary agent. The composite material has a series of outstanding advantages of excellent low-temperature impact performance, high strength, high modulus, high heat stability, easy processing and molding, and the like, and has wide application fields such as automobiles, aeronautics and astronautics, etc.

The present invention relates to a preparation method of ultrahigh molecutar weight polyethylene porous membrane, specially, it relates to a method for preparing high-performance ultrahigh molecular weight polyethylene (UHMWPE) porous membrane by adopting thermal phase separation process. It is characterized by that it uses a high-temperature-resistant solvent-resistant high-strength ultrahigh molecular weight polyethylene resin as membrane material, under the action of diluting agent said invention makes the polyethylene resin membrane material undergo the processes of solution preparation, extrusion, drawing, cooling extraction and recovering extracting agent so as to obtain the invented ultrahigh molecular weight polyethylene porous membrane. The described diluting agent can be selected from white camphor oil, paraffin and paraffin oil.

A method for manufacturing of ultrahigh molecular weight polyethylene (UHMWPE) for implants, where the implants have been machined out of UHMWPE blocks or extruded rods, has anthocyanin dispersely imbedded in the polyethylene. The implant is then exposed to γ ray or electron beam irradiation in an amount of at least 2.5 Mrad followed by a heat treatment to prevent the implant from becoming brittle in the long term as well as to improve strength and wear. The method includes mixing a powder or granulate resin of UHMWPE with an aqueous liquid that contains anthocyanin in a predetermined amount. The water is then evaporated in order to deposit the anthocyanin in a predetermined concentration on the polyethylene particles. The doped UHMWPE particles are compressed into blocks at temperatures in a range of approximately 135° C.-250° C. and pressures in a range of approximately 2-70 MPa. Medical implants are made from the blocks.

The invention provides a medical implant or medical implant part comprising porous ultrahigh molecular weight polyethylene having a weight average molecular weight of about 400,000 atomic mass units or more and a porosity of about 15% to about 65%. The invention further provides a process for producing a medical implant or medical implant part.

The invention discloses a method and equipment for preparing ultrahigh molecular weight polyethylene fibers. The method comprises the following steps of: blending and melting ultrahigh molecular weight polyethylene and a modifier to prepare a granular or powdery modified ultrahigh molecular weight polyethylene raw material; melting and extruding the raw material by using an extruder to form melt of which a flow rate is 0.01 to 0.2 grams per 10 minutes, feeding the melt to a spinning mould by using a melt pump to form melt strips, and cooling and pre-stretching the melt strips to obtain primary yarns; and stretching the primary yarns in a plurality of stages to obtain the ultrahigh molecular weight polyethylene fibers. The equipment comprises the extruder, the melt pump, the spinning mould, a cooling channel, a three-roller tractor, a primary hot-stretching box, a first seven-roller tractor, a secondary hot-stretching box, a second seven-roller tractor, a rinsing trough, a drying box and a winder which are arranged sequentially. The method and the equipment have the characteristics of continuous production capability, relatively shorter process flow, relatively fewer equipment components, no need of solvent, low production cost and the like.

The abrasion resistance of organic fiber based ropes and cords is increased by a outer woven cover of tapes of high molecular weight and more preferably ultrahigh molecular weight polyethylene

Novel gas-permeable membranes which are particularly useful in the packaging of fresh cut fruit and vegetables, and other respiring biological materials. The membranes have an O₂ permeability of at least 775,000 ml/m².atm.24 hrs, a P₁₀ ratio of at least 1.3, and a ratio of CO₂ permeability to O₂ permeability (R) of at least 1.5, and are made by forming thin polymeric coatings on microporous polymeric films. Preferred coating polymers are side chain crystalline polymers. Preferred microporous films contain inorganic fillers, particularly such films based on ultrahigh molecular weight polyethylene or polypropylene. FIG. 1 illustrates how O₂ permeability and R ratio vary for different coating polymers and microporous films.

A cross-linkable polyolefin composition (polyethylene, polypropylene or an ethylene-propylene copolymer) is coextruded with ultrahigh molecular weight polyethylene to form two-layer separator membranes, or three-layer separator membranes, for lithium-ion battery cells. In three-layer separator membranes, the cross-linkable polyolefin is formed as the outer faces of the separator for placement against facing surfaces of cell electrodes. The polymer materials initially contain plasticizer oil, which is removed from the extruded membranes, and the extruded membranes are also stretched to obtain a suitable open pore structure in the layered membranes to provide for suitable infiltration with a liquid electrolyte. The cross-linked polyolefin layer provides strength at elevated temperatures and the lower-melting, ultrahigh molecular weight polyethylene layer provides the separator membrane with a thermal shutdown capability.