Abstract:
Disclosed are an aramid composite which satisfies bulletproof performance required for the related art, is lightweight and exhibits superior adhesive strength, and a method for producing the same. The aramid composite includes an aramid fabric, an adhesive layer and a metal substrate, wherein at least one of the surface of the aramid fabric and the surface of the metal substrate is modified.
Abstract:
Disclosed are wholly aromatic polyamide filament and a method of manufacturing the same, characterized in that, in a process of preparing wholly aromatic polyamide polymer, a multiple tubular feed pipe for polymeric monomer and polymerization solvent with specific construction of adjacent inner paths 11a and outer paths 11b which are alternately arranged one another is used to feed either aromatic diacid chloride A or aromatic diamine dissolved in the polymerization solvent B into a polymerization reactor 20 through corresponding one among the inner and outer paths 11a and 11b. The present invention is effective to progress uniform and homogeneous polymerization over all of area of a polymerization reactor 20 leading to reduction of deviation in degree of polymerization, since polymeric monomers are miscible and react together very well immediately after putting the monomers into the reactor 20. Accordingly, the wholly aromatic polyamide filament produced exhibits narrow PDI and increased ACS, so as to considerably improve strength and modulus thereof.
Abstract:
A high voltage DC power supplier includes: a transformer driven by a switching device, transforming an input voltage to a certain level of high voltage, and outputting the transformed high voltage; a diode and a capacitor for rectifying and smoothing the high voltage outputted from the transformer, and supplying the smoothed voltage to an ER fluid application unit; a discharge circuit for forcibly discharging the output voltage when an output voltage of the capacitor descends; and a controller for controlling a turn-on operation of the switching device on the basis of a difference value between the output voltage and a reference voltage so that the output voltage can follow a target voltage, and outputting a control signal for driving the discharge circuit to the discharge circuit when it reaches a discharge period.
Abstract:
Disclosed is a method for manufacturing carbon fiber which comprises the use of un-reacted raw material monomers in solution to prepare the precursor fiber for making the carbon fiber, and a relatively short passage period through hydrogen, which reduce production costs and increase returns. The present invention further comprises the carbon fiber precursors made thereby.
Abstract:
The present invention relates to a method for treating high-strength fabric to be water-repellent, which includes dipping a high-strength fabric in a water-repellent agent composition to impregnate the high-strength fabric with the water-repellent agent composition, and then, using an air-suction machine to pick-up a part of the water-repellent agent composition impregnated in the high-strength fabric before drying and heating the same. The present invention has advantages in that a part of the water-repellent agent composition impregnated in the high-strength fabric may be uniformly picked-up during dipping, so as to improve water-repellent performance, especially, water-repellency after friction as well as initial water-repellency, and may effectively prevent occurrence of wrinkles on the high-strength fabric during water-repellent treatment. The high-strength fabric obtained by water-repellent treatment according to the present invention exhibits increased flexibility without wrinkles, so as to improve wearing comfort. Further, in case of using the fabric as a raw fabric for bulletproof garments, water-repellency is increased to prevent deterioration in bulletproof properties caused by water absorption.
Abstract:
Disclosed are wholly aromatic polyamide filament and a method of manufacturing the same, characterized by comprising multi-stage injection of a coagulant with sulfuric acid concentration lowered sequentially stage by stage, to a spun material fed into a coagulant injection tank. The present invention enables increase of a spinning and take-up velocity without occurrence of thread cutting by uniformly and evenly coagulating surface and inside of the spun material. In addition, the present invention recovers the coagulant or water already used and reuses the recovered coagulant or water in the earlier stages, so that it has advantages of saving production costs and reducing environmental contamination. Accordingly, the wholly aromatic polyamide filament produced according to the present invention has high crystallinity X, large apparent crystal size ACS and reduced defects in the crystal itself, thereby exhibiting more improved physical properties such as strength and modulus.
Abstract:
Disclosed are to a superabsorbent yarn capable of minimizing the degradation of strength and elongation thereof after coated with a superabsorbent material and minimizing white powders which might be caused and impose processing difficulties during an optical cable manufacturing process and a method for manufacturing the same. The superabsorbent yarn of the invention comprises a yarn and a superabsorbent material coated on the yarn, wherein the superabsorbent material comprises crosslinked polyurethane.
Abstract:
Disclosed are wholly aromatic polyamide filament and a method of manufacturing the same, characterized by comprising multi-stage injection of a coagulant with sulfuric acid concentration lowered sequentially stage by stage, to a spun material fed into a coagulant injection tank. The present invention enables increase of a spinning and take-up velocity without occurrence of thread cutting by uniformly and evenly coagulating surface and inside of the spun material. In addition, the present invention recovers the coagulant or water already used and reuses the recovered coagulant or water in the earlier stages, so that it has advantages of saving production costs and reducing environmental contamination. Accordingly, the wholly aromatic polyamide filament produced according to the present invention has high crystallinity X, large apparent crystal size ACS and reduced defects in the crystal itself, thereby exhibiting more improved physical properties such as strength and modulus.
Abstract:
Disclosed are wholly aromatic polyamide filament and a method of manufacturing the same, characterized by comprising multi-stage injection of a coagulant with sulfuric acid concentration lowered sequentially stage by stage, to a spun material fed into a coagulant injection tank. The present invention enables increase of a spinning and take-up velocity without occurrence of thread cutting by uniformly and evenly coagulating surface and inside of the spun material. In addition, the present invention recovers the coagulant or water already used and reuses the recovered coagulant or water in the earlier stages, so that it has advantages of saving production costs and reducing environmental contamination. Accordingly, the wholly aromatic polyamide filament produced according to the present invention has high crystallinity X, large apparent crystal size ACS and reduced defects in the crystal itself, thereby exhibiting more improved physical properties such as strength and modulus.
Abstract:
The present invention relates to a para-fully aromatic polyamide pulp, its preparing process and its preparing equipment, more particularly, it is assemble of micro fibrils having less than 1 .mu.m in its average diameter and crushed oval shaped cross-section wherein the longest distance is at least 1.2 times than the shortest distance.Also, the present invention relates to a continuous process and equipment preparing for the above aromatic polyamide pulp by orienting and maturing or orienting, maturing and cutting the pre-polymer (non-oreinted) that aromatic diamine has been reacted with equivalent mole of aromatic diacid chloride in polymerization solvent.