摘要:
Polybenzazole fibers can be rapidly dried without undue fiber damage by exposing them to two or more set point temperatures with the temperatures being selected relative to the residual moisture content of the fiber. The residence time required for the fiber at each progressively higher temperature can be reduced if the fiber is always in full contact with the set point temperature of the drying equipment.
摘要:
Improved polybenzoxazole fibers are made by a process for drying a wet, coagulated polybenzoxazole (PBO) fiber including the steps of:(a) drying the fiber at a temperature of no more than 300.degree. C. under a tension of at least about 1 gram per denier (gpd) until it retains no more than about 120 weight percent residual moisture content;(b) further drying the fiber at a temperature of no more than 300.degree. C., either with or without tension, until it contains no more than about 20 percent residual moisture content; and(c) heat-treating the fiber at a temperature of at least about 300.degree. C. under tension.
摘要:
The present invention relates to a process for preparing a microporous permselective membrane from a poly(phenylene sulfide) (PPS) polymer, an organic compound which substantially solubilizes the PPS below its melting point to form a homogenous mixture, heating the resulting mixture, extruding or casting the mixture into a membrane (fiber or film), quenching or coagulating the membrane, and leaching the membrane, while optionally drawing the membrane before, during, after leaching, or a combination thereof. In one embodiment, the solvent optionally includes an organic non-solvent to assist in obtaining the desired microporsity. The permselective polymers are useful to separate gaseous or liquid components from a mixture of components.
摘要:
High boiling point polar organic solvent are useful solvents for poly(etheretherketone)-type polymers (PEEK). Solutions of PEEK may be used to form PEEK articles such as film, microporous sheet membrane, fiber and microporous hollow fibers. The microporous PEEK is useful as an ultrafiltration membrane and as a substrate for the formation of reverse osmosis membranes. A method of making PEEK articles including microporous sheet membranes is disclosed. A method of making PEEK fibers including microporous hollow membrane fibers is disclosed.
摘要:
An extruded or molded article containing iron based oxygen scavenger, electrolytes, activated carbon, silica gel, or other water absorbing media, and optionally pore formers, is subjected to deformation to create voids or porosity, and subjected to water spraying or dipping to obtain a water activity of 0.4 or higher. The article is placed in a container or package containing oxygen sensitive articles.
摘要:
The present invention relates to encapsulated activated carbon and a method of preparing the same to protect the structure of the activated carbon and preserve the odor absorbing capability of the activated carbon particles. Particularly, the present invention is directed to a polymer article having odor absorption capabilities comprising a film comprising a matrix polymer and activated carbon particles at least partially encapsulated with a non-water soluble amorphous polymer, wherein the non-water soluble amorphous polymer is incompatible with the matrix polymer. The polymer article can be a bag.
摘要:
Single and multilayer porous polyolefin films are prepared by extruding polyolefin with poly(lactic acid) (PLA) and followed by uniaxial or biaxial stretching. PLA is used as a pore former that creates porosity. The film provides adjustable gas and water vapor transmission rate by varying the PLA content. Sorbents may optionally be added in the formulation in selective layers. The porous films are useful in packaging and consumable applications. In particular, partially miscible blends of PP and PLA is useful for creating fine porosity due to the fine PLA domains in the miscible blends.
摘要:
The invention provides an article for oxygen absorption comprising a container containing a water-soluble ion source, an water activated oxygen scavenger, and a rupturable canister of hydrated polymer.The invention provides in another embodiment a method for providing timed or controlled oxygen absorption comprising providing an article for oxygen absorption comprising a container containing a water-soluble ion source, an water activated oxygen scavenger, and a rupturable canister of hydrated polymer, rupturing the canister, whereby the hydrated polymer and water-soluble ion source come in contact and release water, and the water as it is released activates the oxygen scavenger.
摘要:
The invention provides for an extended shelf life package comprising a material for human ingestion that degrades by oxidation, comprising an oxygen scavenger comprising a transition metal oxygen scavenger, a container substantially impervious to oxygen, wherein the container has a filter suspended in the container, the filter holds the material for human ingestion, and the container also holds the oxygen scavenger.In another embodiment, the invention provides for an extended shelf life package comprising human ingestible material that degrades by giving off CO2 comprising a carbon dioxide scavenger, a container substantially impervious to carbon dioxide, wherein the container has a filter suspended in the container, the filter holds the human ingestible material, and the container also holds the carbon dioxide scavenger.
摘要:
Bags or liners having incorporated therein an effective amount of odor management agents including a counteractant agent, a neutralizing agent and optionally, a masking agent, whereby the odor management agent imparts no perceptible scent to the bags or liners, such that the bags or liners are substantially free of fragrance while the odor management agent reduces malodor emanating from products disposed within the bag. Further, the invention is drawn to web materials for use in forming the bags or liners having odor management agents. The odor management agent is disposed within the bag or dispersed substantially uniformly throughout the web.