摘要:
Continuous polymeric extrusion nucleation systems and methods useful for making polymeric microcellular foamed materials, including crystalline and semi-crystalline polymeric microcellular materials, are provided. Pressure drop rate is an important feature in some embodiments, and the invention provides systems for controlling these and other parameters. One aspect involves a multiple-pathway nucleator that is separated from a shaping die by a residence chamber. Another aspect involves a die for making advantageously thick articles, including a multiple-pathway nucleation section. Microcellular material can be continuously extruded onto wire, resulting in a very thin, essentially closed-cell microcellular insulating coating secured to a wire. Other very thin microcellular products can be fabricated as well.
摘要:
The invention relates to a stopper for use in a substantially cylindrical bottle opening. The stopper has a substantially cylindrical shape to seal the bottle opening and includes a first polymer portion and a second material portion, wherein the second material portion coaxially overlies the first polymer portion. In another embodiment, the stopper includes a third polymer portion wherein the first polymer portion coaxially overlies the third polymer portion. The invention also relates to a method of protecting liquid in a bottle with a substantially cylindrical bottle opening. The method includes providing a stopper having a substantially cylindrical shape to seal the bottle opening and closing off the bottle by insertion of the stopper into the bottle opening. The invention also relates to a method of producing a stopper for use in a substantially cylindrical bottle opening. In one embodiment, the method includes extruding a first polymer portion through an extrusion die, coaxially coating the first polymer portion with a second material portion to form a body, and forming the body into a shape to substantially seal the bottle opening. The first polymer portion and the second material portion may be formed by co-extrusion or in a step-wise manner.
摘要:
A method using a two part process line is proposed for manufacturing foams from polymers or polymer mixtures useful for making molded bodies. The process line is divided into at least one first part and one second part. The polymer or polymer mixture is melted in the first part and a gas at a pressure increased relative to the melt pressure is added with the influence of a shearing and/or kneading device on the melted polymer or polymer mixture enriched with gas. In the second part of the process line, foam is formed from the gas-enriched polymer or polymer mixture at a higher pressure than the pressure in the first part of the process line. Membranes can be made from the molded bodies made by the method described above.
摘要:
The invention comprises a fully continuous process for shaping a high internal phase emulsion (HIPE) with a polymerizable continuous phase into dry foam, comprising 1) providing a high internal phase emulsion (HIPE) comprising (a) at least 70 percent by volume of an eternal phase comprising one or more polymerizable monomer; (b) a surfactant in an amount effective to produce a high internal phase emulsion; and (c) an internal phase; 20 depositing the emulsion onto a lower moving support substrate; 3) leveling the emulsion to a desired thickness above the support substrate; 4) polymerizing the monomers by running the emulsion and the lower moving support substrate through a heating zone for a time sufficient to polymerize at least 75% of the monomer in the HIPE by the end of the heating zone; and 5) drying the polymerized HIPE in a drying zone for a time sufficient to produce a foam having greater than 50% of the internal phase removed.
摘要:
A stopper for use in a substantially cylindrical bottle opening having a substantially cylindrical shape to seal the bottle opening and including a first polymer portion and a second polymer portion, wherein the second polymer portion coaxially overlies the first polymer portion. In another embodiment, the stopper includes a third polymer portion wherein the first polymer portion coaxially overlies the third polymer portion. A method of protecting liquid in a bottle with a substantially cylindrical bottle opening including providing a stopper having a substantially cylindrical shape to seal the bottle opening and closing off the bottle by insertion of the stopper into the bottle opening. A method of producing a stopper for use in a substantially cylindrical bottle opening comprising extruding a first polymer portion through an extrusion die, coaxially coating the first polymer portion with a second polymer portion to form a body.
摘要:
An apparatus for forming a nonwoven fibrous web wherein the web contains at least one binder fiber and at least one support fiber. The apparatus comprises a mixer for creating a homogeneous mixture of the fibers, a conveyor for transporting the resulting fiber mixture to a shaker chute, an oscillating mechanism which acts on the fiber mixture, a depositing mechanism for depositing the fiber mixture onto a horizontal planar surface, a heater for heating the mixture to a temperature to fuse the binder and support fibers, and a cooling mechanism to cool the mixture after heating.
摘要:
The process for fabricating an orthotic joint of the present invention involves creating a casting mold of the anatomical joint for which the brace is being fitted. Then layers of nylon and cross-link carbon composite grade and the PVA bag are placed over the mold as is done in typical laminating processees for such braces. Then, a series of reinforcing strips of nylon and composite are attached to the layup in the same location where the sidebars would normally be located. The bottom layer which is typically a layer of nylon stockinette is the longest of the layers and the nylon strips are alternated with the composite strips with each successive strip being shorter than the strip immediately below it. A dummy disk is then provided at the joint. A second set of strips is then positioned where the upper sidebar would be located. Additional laminating substrate materials of nylon and cross-link carbon composite braid and a PVA bag are then placed over the structure. An acrylic/epoxy resin, accelerant and other materials used in the laminating process are poured over the brace. Once the layup is dried the brace is cut around the dummy disk partially through the brace from the outside on the lower-end and from the inside on the upper-end so that the brace can then be separated into two units. The dummy disk is then removed and a range of motion disk is inserted.
摘要:
The present invention generally relates to processes for preparing extruded foam products and more particularly to a process for producing such products wherein surface defects are minimized. There has been a movement to replace conventional halo-carbon blowing agents in favor of purportedly more environmentally safe halo-carbon free blowing agents such as carbon dioxide, nitrogen, argon, water, air, nitrogen, and helium. However, these halo-carbon free blowing agents, in particular carbon dioxide, have higher foaming rates and higher volatility leading to greater surface defects in the extruded foam. The present invention employs polyethylene wax to reduce or eliminate the occurrence of surface defects where halo-carbon free blowing agents are employed in an extruded foam manufacture process. The polyethylene wax containing extruded foam products of this invention are characterized by a generally smooth substantially defect free surface and contain a majority of closed cells which are free of any trapped halo-carbon blowing agents.
摘要:
An air handler for collecting air discharged from a melt spinning apparatus. The air handler includes an outer housing having walls defining a first interior space. One of the walls has an intake opening for receiving the discharge air. Another wall has an exhaust opening for discharging the air. The intake opening is in fluid communication with the first interior space. An inner housing is positioned within the first interior space and has walls defining a second interior space. At least one of the walls of the inner housing has an opening. The first interior space communicates with the second interior space through the opening. The second interior space is in fluid communication with the exhaust opening.
摘要:
Semi-crystalline microcellular foams that include a midlevel amount of nucleating agent, and methods of their production, are provided. The microcellular foams can be produced in typical polymer processing techniques such as extrusion, injection molding and blow molding. The foams exhibit excellent mechanical properties and can be formed over a broad range of density into a number of different foam articles.