摘要:
A polycarbonate composition comprising: a high heat copolycarbonate comprising high heat carbonate units, wherein a homopolycarbonate of the high heat carbonate units has a glass transition temperature (Tg) of 155-250 °C; and optionally low heat carbonate units, wherein a homopolycarbonate of the low heat carbonate units has a Tg of up to 150 °C, each as determined by differential scanning calorimetry as per ASTM D3418 with heating rate of 20 °C/min; greater than 200-5000 ppm of an aryl benzofuranone stabilizer, based on the total parts by weight of the composition, wherein a 3.2 millimeter-thick molded sample aged for 250 hours at 150 °C has a change in a yellowness index value of less than 6.0, or less than 5.0, or less than 3.0 as compared with an initial yellowness index value of the molded sample, as measured in accordance with ASTM D1925.
摘要:
A copolycarbonate optical article comprises a polycarbonate composition including: a copolycarbonate having: 2 to 60 mol% of phthalimidine carbonate units, 2 to 90 mol% of high heat carbonate units, and optionally 2 to 60 mol% of bisphenol A carbonate units. The copolycarbonate has less than 100 ppm of each of phthalimidine, high heat bisphenol, and bisphenol A monomers, and less than 5 ppm of various ions, and is prepared from monomers each having a purity of at least 99.6%. The polycarbonate composition has a glass transition temperature of 200 ºC to and a yellowness index of less than 30.
摘要:
A copolycarbonate comprises first repeating units, second repeating units different from the first repeating units, and third repeating units different from the first and second repeating units; and wherein the first repeating units are phthalimidine carbonate units, the second repeating units are carbonate units of the formula (I) wherein R c and R d are each independently a C 1-12 alkyl, C 2-12 alkenyl, C 3-8 cycloalkyl, or C 1-12 alkoxy, each R 6 is independently C 1-3 alkyl or phenyl; X a is a C 6-12 polycyclic aryl, C 3-18 mono- or polycycloalkylene, C 3-18 mono- or polycycloalkylidene, -(Q 1 )x-G-(Q 2 )y- group wherein Q 1 and Q 2 are each independently a C 1-3 alkylene, G is a C 3-10 cycloalkylene, x is 0 or 1, and y is 1; and m and n are each independently 0 to 4; and the third repeating units are carbonate units (II) wherein R e and R f are each independently C 1-12 alkyl, C 2-12 alkenyl, C 3-8 cycloalkyl, or C 1-12 alkoxy, a and b are each independently integers of 0 to 4, and X b is a single bond, -0-, -S-, - S(0)-, -S(0) 2 -, -C(0)-, or C 1-32 bridging hydrocarbon group, provided that X b is not a phthalimidine group or X a .
摘要:
Disclosed herein is a method of preparing a polymer dispersion including combining a first solution with a second solution to provide an emulsion, and removing the first solvent from the emulsion to provide a dispersion including a plurality of polymer particles. The first solution includes a first solvent, a polyetherimide, a polycarbonate, or a combination of at least one of the foregoing, and optionally a nonionic surfactant. The second solution includes an aqueous solvent, and optionally a nonionic surfactant. The polymer particles have an average particle size (D50) of less than or equal to 20 micrometers. Also described are polyetherimide dispersions including a plurality of polyetherimide particles, wherein at least 90% of the particles have a particle size less than or equal to 14 micrometers, a nonionic surfactant, and an aqueous carrier.
摘要:
Described herein are N-substituted monomers and polymers, methods of making such monomers and polymers, and methods of using them in various applications, such as medical devices. In preferred embodiments, the medical device is a stent.
摘要:
Preferred embodiments of the present invention relate to polymeric medical devices, such as stents. More particularly, the compositions disclosed herein comprise halogen-containing phenol moeities, that may be used for medical devices and other uses whereby bioresorbable and radiopaque and physicomechanical properties are desired.
摘要:
In one embodiment the preset invention is a polycarbonate comprising structural units derived from at least one dihydric phenol, a carbonate precursor, and at least one member selected from the group consisting of an oxanilide-comprising compound, an oxamate-comprising compound, and mixtures thereof. In another embodiment the present invention is a method for making a polycarbonate comprising structural units derived from at least one dihydric phenol and at least one member selected from the group consisting of an oxanilide-comprising compound, an oxamate-comprising compound, and mixtures thereof, which comprises the step of contacting under reactive conditions at least one dihydric phenol, a carbonate precursor, and at least one member selected from the group consisting of an oxanilide-comprising compound, an oxamate-comprising compound, and mixtures thereof. In still another embodiment the present invention is an article comprising a policarbonate comprising oxanilide structural units. In still another embodiment the present invention is a method for making a symmetrical or unsymmetrical oxanilide-comprising dihydric phenol which comprises the step of contacting at least one aromatic amine bearing a hydroxy group with a diaryl oxalate or a dialkyl oxalate bearing alkyl groups each substituted with at least one electron-withdrawing group. In still another embodiment the present invention is a method for making an oxamate-comprising monohydric phenol which comprises the step of contacting an aromatic amine bearing a hydroxy group with a diaryl oxalate or a dialkyl oxalate bearing alkyl groups each substituted with at least one electron-withdrawing group.
摘要:
A polymer whose repeating units include a side-chain and, between the atom or group to which the side-chain is bonded, a backbone chain, in which the chains are each at least four atoms long and are chemically incompatible, one chain being at least predominantly hydrocarbon and the other comprising a C4+ perfluorocarbon group.