Abstract:
Disclosed are process controls for controlling the continuous preparation of nylon salt solution. The process controls include feed forward controls. A model is generated to achieve a target pH and/or salt concentration. Feed rates are set for each of a dicarboxylic acid monomer, a diamine monomer, and/or water to a single continuous stirred tank reactor. The dicarboxylic acid is metered, based on weight, from a loss-in-weight feeder to the reactor. The nylon salt solution is formed continuously and has low variability from a target pH and/or a target salt solution concentration. The nylon salt solution is transferred directly to a storage tank, without further monomer addition, pH adjustment, or salt solution adjustment after exiting the continuous stirred tank reactor.
Abstract:
Described herein are methods of preparing high molecular weight polyamides which reduce or eliminate the production of unwanted gels during the production process. These methods reduce the formation of undesired polyamide gel by polishing the internal surfaces of the production equipment, thereby providing surfaces with smaller surface roughness values.
Abstract:
Disclosed are processes for applying dyes, stain blocker and anti-soil compositions on BCF yarns during cable or air twisting processes, or heat setting processes, prior to weaving, knitting or tufting. Further discloses are process for applying dyes, stain blocker and anti-soil compositions on BCF yarns prior to heat setting. The processes forego the need to dye and otherwise treat carpets and other textiles made from the BCF yarn using current methods. Also disclosed are systems, BCF yarns, and carpets made from the BCF yarn treated by the disclosed process.
Abstract:
Provided is a garment including hosiery which avoids the needs for a conventional waistband by providing a graduated compression panty where the compression is gradually increased from the bottom of the panty where leg portions are attached to the top of the panty which corresponds approximately with the waist of the wearer.
Abstract:
Circular knit, elastic fabrics (10) of at least one of single jersey, French terry, and fleece are disclosed that include a bare elastomeric material (12) plated with spun and/or continuous filament hard yarns (14) . The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece are manufactured by a method that does not require a dry heat setting step. The method requires drafting the bare elastomeric material no more than about 2.5x its original length when knitting to form the circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece.
Abstract:
Disclosed is a method for hydrogenating a dinitrile to form a diamine. Also disclosed is a method for preparing a catalyst for this hydrogenation reaction by reducing iron oxide with hydrogen. The catalyst ages during the course of making the diamine. An aged catalyst is partially reactivated by interrupting the flow of dinitrile and ammonia feed to a reactor, while maintaining a flow of hydrogen to the reactor.
Abstract:
The present disclosure provides methods and apparatuses estimating casting throughput during casting process to provide polyamide pellets. The method of estimating casting throughput of an extruded polyamide polymer comprises measuring an amount of casting water flowing in to a casting apparatus typically from two or more locations, measuring the temperature of the casting water flowing in, and measuring the temperature of the casting water flowing out. Additional steps include calculating a heat transfer between the casting water flowing in and the casting water flowing out using the measured amount, and correlating the heat transfer to the casting throughput.
Abstract:
Disclosed are nylon salt solution preparation processes including a trim diamine feed. The nylon salt solution is prepared by feeding a dicarboxylic acid monomer and a diamine monomer to a single continuous stirred tank reactor. The dicarboxylic acid is metered, based on weight, from a loss-in-weight feeder to the reactor. The nylon salt solution is formed continuously and has low variability from a target pH and/or a target salt solution concentration. The nylon salt solution is transferred directly to a storage tank, without further monomer addition, pH adjustment, or salt solution adjustment after exiting the continuous stirred tank reactor.
Abstract:
Disclosed are nylon salt solution preparation processes including a loss-in-weight feeder and a continuous stirred tank reactor. The nylon salt solution is prepared by feeding a dicarboxylic acid monomer and a diamine monomer to a single continuous stirred tank reactor. The dicarboxylic acid is metered, based on weight, from a loss-in-weight feeder to the reactor. The nylon salt solution is formed continuously and has low variability from a target pH and/or a target salt solution concentration. The nylon salt solution is transferred directly to a storage tank, without further monomer addition, pH adjustment, or salt solution adjustment after exiting the continuous stirred tank reactor.
Abstract:
A method for unwinding yarn is provided that allows for maximizing the draft of the yarn, while monitoring tension. The method includes providing a yarn package including elastic yarn; choosing a selected draft for said elastic yarn; unwinding the elastic yarn from the yarn package from a driven roll to yarn processing equipment at the selected draft which is determined by a ratio of a speed of the yarn at the yarn processing equipment to a speed of the driven roll; measuring tension in the elastic yarn; and providing an alarm when said tension reaches a critical level.