摘要:
A process for making PBZ fibers of ultra-high physical properties is given. Polybenzoxazole fibers made by the process of this invention have tensile strengths nearly double in value from what has been reported previously.
摘要:
A process for making PBZ fibers of ultra-high physical properties is given. Polybenzoxazole fibers made by the process of this invention have tensile strengths nearly double in value from what has been reported previously.
摘要:
Polybenzazole polymer dopes are spun through a spinneret having more than 2 per cm.sup.2, of orifices in relatively close proximity. The dope filaments formed, then pass through an air gap which has a temperature of 50.degree. to 100.degree. C. and a gas flow sufficient to uniformly reduce the temperature of the dope filaments. The filaments cool in the air gap and are then coagulated.
摘要:
Polybenzazole polymer dopes are spun into fibers at high speed by passing through a spinneret with proper selection of hole geometry, followed by spin-drawing to a spin-draw ratio of at least 20, washing, taking up and drying. The take up speed is at least about 150 meters per minute, and the fibers are spun in at least 10 km lengths without a break.
摘要:
This invention aims at improvement of heat-treatment technology for manufacture of large amounts of polybenzazole fibers. The fibers are heat treated in a device that provides for a rapid, cocurrent, countercurrent or both cocurrent and countercurrent flow of heat treatment gas.
摘要:
The invention relates to an article for oxygen absorption that is a container containing a water-soluble on source, a water activated oxygen scavenger, and a rupturable canister of hydrated polymer. The hydrated polymer comprises a superabsorbent polymer. The water-soluble on source comprises a salt. The invention in another embodiment relates to a method for providing timed oxygen absorption using the article as above with rupturing of the canister to release the water carrying superabsorbent such that it will contact the oxygen scavenger and on source thereby leading to activating the oxygen scavenger.
摘要:
A low-gloss biaxially oriented polymer film containing a vinyl aromatic polymer and substantially non-spherical rubber particles is useful for window film applications. The rubber particles, when unconstrained, are essentially spherical and have a rubber particle size of 2.5 micrometers or more.
摘要:
A continuous process for heating a polybenzazole or polybenzothiazole filament, which includes the step of heating the filament to a temperature of at least 100.degree. C. but no greater than 290.degree. C. while applying a tension thereto of at least 3.5 grams per denier, which is carried out at a line speed of at least 100 m/minute; and there is no prior or subsequent heating of the fiber to any temperature greater than 300.degree. C. It has been discovered that placing tension on the filament while it is dried increases its tensile modulus without a significant decrease in its tensile strength.
摘要:
Asymmetric membranes are prepared by selectively treating a major surface of an incompatible polymer blend prepared by melt blending having at least one extractable polymer component and then contacting the polymer blend with a solvent to extract the extractable polymer component. The treated surface becomes the dense layer of the membrane. The major surface is treated by crosslinking, by contacting the surface with a crosslinking agent which is subsequently cured, or by contacting the surface with an agent which reacts with groups on the surface and imparts a polar character to it.
摘要:
The invention relates to an oxygen scavenging material comprising an oxygen scavenger disbursed in a low density foam, wherein the oxygen scavenger has a particle size of less than 25 μm. In another embodiment the invention relates to a product package comprising a foam tray, product in the tray, and a polymer cover surrounding the meat and tray, wherein the foam tray comprises an oxygen scavenging material, wherein the oxygen scavenging material comprises an oxygen scavenger disbursed in the foam and wherein the oxygen scavenger has a particle size of less than 25 μm.