5357 results about "Vitrification" patented technology

An implantable medical device is disclosed. The device is fabricated at least in part from a biocompatible, biodegradable composition. The composition is composed of a biocompatible, biodegradable polymer and a biocompatible, biodegradable wax. The concentration of the wax at the surface of the device is greater than the concentration of the wax in the body of the implantable device. The increased concentration of wax at the device surface may be attained when the device is heated to a temperature greater than the melting point of the wax and the glass transition temperature of the polymer, but lower than melting point of the polymer.

A process is disclosed for forming a synthetic fiber including providing a first component of an aliphatic polyester polymer a second component of a multicarboxylic acid, mixing the first component aliphatic polyester polymer and the second component multicarboxylic acid to form an unreacted specified thermoplastic composition, and melt blending the unreacted specified thermoplastic composition in an extruder or a mixer. The second component multicarboxylic acid lubricates the extruder and provides a nucleating agent for crystallizing the specified thermoplastic composition to form a mean crystal size less than about 120 Angstroms. Fiber composed of the specified thermoplastic composition has a mean crystal size less than about 120 Angstroms. The fiber has a glass transition temperature (Tg) less than about 55 DEG C. In one aspect, a first component of polylactic acid and a second component of adipic acid provide synthetic fibers in a nonwoven structure used in a biodegradable and compostable disposable absorbent product for the absorption and removal of body fluids.

A hollow sphere organic pigment in which a core containing a void is encapsulated by a first shell polymer having a glass transition temperature greater than 50 DEG C., the first shell having polymerized thereon a second shell polymer having a glass transition temperature of -15 DEG C. to -50 DEG C. is provided. Also provided is a paper or paperboard coating composition containing the hollow sphere organic pigment, a method for improving the strength and opacity of a paper or paperboard coating by using the coating composition dried, a coated paper or paperboard bearing the dried coating composition, and a method for improving the strength and opacity of paper or paperboard by incorporating a particular hollow sphere organic pigment into the formed wet sheet.

The present invention relates to a high modulus macroscopic fiber comprising single-wall carbon nanotubes (SWNT) and an acrylonitrile-containing polymer. In one embodiment, the macroscopic fiber is a drawn fiber having a cross-sectional dimension of at least 1 micron. In another embodiment, the acrylonitrile polymer-SWNT composite fiber is made by dispersing SWNT in a solvent, such as dimethyl formamide or dimethyl acetamide, admixing an acrylonitrile-based polymer to form a generally optically homogeneous polyacrylonitrile polymer-SWNT dope, spinning the dope into a fiber, drawing and drying the fiber. Polyacrylonitrile/SWNT composite macroscopic fibers have substantially higher modulus and reduced shrinkage versus a polymer fiber without SWNT. A polyacrylonitrile/SWNT fiber containing 10 wt % SWNT showed over 100% increase in tensile modulus and significantly reduced thermal shrinkage compared to a control fiber without SWNT. With 10 wt % SWNT, the glass transition temperature of the polymer increased by more than 40° C.

A solar cell module of the present invention was made to improve adhesion between electrodes, which is formed with thermosetting resin containing silver paste, of a solar cell element and connecting tabs coated with lead (Pb) free solder. To achieve this purpose, the solar cell module is comprised of a front surface member, a rear surface protective member, a plurality of solar cell elements provided between the front surface member and the rear surface protective member, and connecting tabs for electrically connecting the solar cell elements to each other through electrodes with the use of lead free solder. The electrodes of the solar cell elements are made of silver paste containing thermosetting resin and silver powder. The thermosetting resin contains epoxy resin at volume ratio of 70% or more having a glass transition rate of 80° C. to 200° C. measured by a TMA method. The connecting tabs coated with lead free solder are soldered to the electrodes.

A method for forming through-wafer interconnects (TWI) in a substrate of a thickness in excess of that of a semiconductor die such as a semiconductor wafer. Blind holes are formed from the active surface, sidewalls thereof passivated and coated with a solder-wetting material. A vent hole is then formed from the opposite surface (e.g., wafer back side) to intersect the blind hole. The blind hole is solder filled, followed by back thinning of the vent hole portion of the wafer to a final substrate thickness to expose the solder and solder-wetting material at both the active surface and the thinned back side. A metal layer such as nickel, having a glass transition temperature greater than that of the solder, may be plated to form a dam structure covering one or both ends of the TWI including the solder and solder-wetting material to prevent leakage of molten solder from the TWI during high temperature excursions. Intermediate structures of semiconductor devices, semiconductor devices and systems are also disclosed.

Methods and compositions relating to powder metallurgy in which an amorphous-titanium-based metal glass alloy is compressed above its glass transition temperature Tg with a titanium alloy powder which is a solid at the compression temperature, to produce a compact with a relative density of at least 98%.

Disclosed are polyester shrink films comprising a voiding agent dispersed within a continuous polyester phase. The voiding agent comprises at least one first polymer and at least one second polymer, in which the polymer components have selected physical properties such as glass transition temperature, melting point, tensile modulus, surface tension, and melt viscosity. The resulting shrink films have high opacity, a low coefficient of friction, lower density, low shrink force, and good printability. The films are useful for sleeve label and other shrink film applications, and their lower density allows them to be readily separated from soft drink bottles, food containers and the like during recycling operations. Also disclosed is a process for separating a void-containing polyester from a mixture of polymers.

Aqueous dispersions are disclosed, having a minimum film formation temperature no greater than about 50° C., that include a multi-stage emulsion polymer made by a process that includes a first polymerization stage, in which a first monomer mixture having a calculated glass transition temperature of at least about 50° C. is polymerized via free radical emulsion polymerization to obtain a first-stage emulsion polymer, and a second polymerization stage, in which a second monomer mixture, having a calculated glass transition temperature from about −30° C. to about 10° C., is polymerized via free radical emulsion polymerization, in the presence of the first-stage emulsion polymer. The dispersions are useful in a variety of coating compositions that exhibit improved block resistance.

A medical article comprising an implantable substrate having a coating is disclosed, the coating comprising a biologically erodable polymer having the glass transition temperature below about −50° C. The biologically erodable polymer can be blended with a polymeric additive which either has the glass transition temperature of about −50° C. or higher, or a degree of crystallinity greater than that of the first polymer.

The invention discloses aluminosilicate glass for chemical tempering and glass ceramics, and particularly discloses aluminosilicate glass which contains Li2O and P2O5 and can be chemically tempered. The glass of the invention can realize high ion exchange speed by the addition of 0.01-8 wt% of P2O5. The glass of the invention contains 2-6 wt% of Li2O, which can reduce the glass melting temperature and the glass-transition temperature. The glass of the invention has a low glass-transition temperature (Tg) of 480-590 DEG C, and the glass hardness is at least 600 Kg/mm2. After chemical tempering, the glass of the invention has a large surface stress layer depth (DoL) and a high surface crushing stress (CS). After tempering in pure KNO3, a potassium ion stress layer is formed, which has a DoL of at least 20 microns and a CS of at least 600 MPa. After tempering in a mixed salt of KNO3 and NaNO3 or two-step tempering in KNO3 and NaNO3, a potassium and sodium ion stress layers can be formed simultaneously, which have a DoL of at least 50 microns and a CS of at least 600 MPa. In addition, the aluminosilicate glass of the invention can be converted into glass ceramics through further heat treatment.

A dimensionally stable and growth controlled inflatable member formed by adding a multifunctional agent to a soft polymer to form a compound, extruding an inflatable member from the compound, and crosslinking the compound. The inflatable member is configured to be formed-in-place with a body lumen. Preferably, the inflatable member is blown to a working diameter prior to use and then heated to the glass transition temperature of the polymer to shrink the diameter of the blown inflatable member back to about the nominal diameter of the tubing. In another embodiment, the invention is a dimensionally stable and growth controlled inflatable member comprising longitudinal zones of crosslinked material symmetrically spaced about the circumference of the inflatable member and a uniform working diameter. Preferably, there are three or more longitudinal zones that run the working length of the inflatable member. The selectively irradiated inflatable members are formed in a mold having symmetrically spaced longitudinal windows.

Shape memory polymers prepared by copolymerizing two monomers, which each separately produce polymers characterized by different glass transition temperatures in the presence of a difunctional monomer whereby the copolymer formed is cross-linked during the polymerization to form a theremoset network. The transition temperature of the final polymers is adjusted by the ratio of the monomers selected, to from about 20 to about 110° C., while the degree of cross-linking controls the rubbery modulus plateau. The shape memory polymers can be processed as castable formulations in the form of coatings and films. The copolymers are optically transparent and are useful as medical plastics. The invention also relates to the articles of manufacture thereof and methods of the preparation and use thereof.

The present invention relates to an epoxy resin composition for a fibre reinforced composite material, which is thermosetting resin composition where the glass transition temperature Tg of the cured material obtained by heating for 2 hours at 180° C. is at least 150° C., and the modulus of rigidity G'R in the rubbery plateau in the temperature region above the aforesaid Tg is no more than 10 MPa. In accordance with the present invention, it is possible to provide a fibre-reinforced composite material which is outstanding in its resistance to hot-wet environmental condition, impact resistance, and strength characteristics such as tensile strength and compression strength, and furthermore it is possible to provide a thermosetting resin composition and a prepreg outstanding in terms of their peel strength to a honeycomb core.

A method for forming biodegradable fibers is provided. The method includes blending polylactic acid with a polyepoxide modifier to form a thermoplastic composition, extruding the thermoplastic composition through a die, and thereafter passing the extruded composition through a die to form a fiber. Without intending to be limited by theory, it is believed that the polyepoxide modifier reacts with the polylactic acid and results in branching of its polymer backbone, thereby improving its melt strength and stability during fiber spinning without significantly reducing glass transition temperature. The reaction-induced branching can also increase molecular weight, which may lead to improved fiber ductility and the ability to better dissipate energy when subjected to an elongation force. To minimize premature reaction, the polylactic acid and polyepoxide modifier are first blended together at a relatively low temperature(s). Nevertheless, a relatively high shear rate may be employed during blending to induce chain scission of the polylactic acid backbone, thereby making more hydroxyl and/or carboxyl groups available for subsequent reaction with the polyepoxide modifier. Once blended, the temperature(s) employed during extrusion of the blended composition can be selected to both melt the composition and initiate a reaction of the polyepoxide modifier with hydroxyl and/or carboxyl groups of the polylactic acid. Through selective control over this method, the present inventors have discovered that the resulting fibers may exhibit good mechanical properties, both during and after melt spinning.

An apparatus and method of uniformly heating, rheologically softening, and thermoplastically forming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool are provided. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to uniformly and rapidly heat a sample or charge of metallic glass alloy to a predetermined “process temperature” between the glass transition temperature of the amorphous material and the equilibrium melting point of the alloy in a time scale of several milliseconds or less. Once the sample is uniformly heated such that the entire sample block has a sufficiently low process viscosity it may be shaped into high quality amorphous bulk articles via any number of techniques including, for example, injection molding, dynamic forging, stamp forging, and blow molding in a time frame of less than 1 second.