Abstract:
A process for producing polymers by the ionogenic polymerization of lactams is disclosed, wherein the lactam monomer, in the liquid state, mixed with a catalyst and promoter is introduced into a heated mold, which rapidly rotates about an axis outside the mold, via a conduit disposed co-axially with respect to the axis and via a feed channel which extends from the conduit at an angle to the axis and the polymerized, molded object is automatically removed from the mold in a radial direction due to centrifugal force.
Abstract:
A process for the recovery of powdery homopolymers or copolymers of ethylene from a polymerization system is disclosed, wherein the corresponding monomers are subjected to polymerization conditions in a reactor and the resulting polymer, together with unconverted monomer, is discharged from the reactor and expanded to a lower pressure. At least part of this mixture is quenched by the addition of a cold gas, which gas is at least one of the polymerization monomers, to a temperature below the melting point of the polymer to solidify the polymer contained in such mixture as the form of a fine powder. Thereafter the powder is separated from the mixture and remaining unconverted monomer is recycled to the reactor. The process involves simpler equipment and reduced utility costs as compared to prior processes.
Abstract:
In order to pulsate liquid in a column, the column is connected to both the suction side and the pressure side of a pump, via rotatable valve means which alternately connects the pressure side and the suction side of the pump to the column. The rotations of the valve and the pumping force and the flow capacity of the piping between the column and the pump primarily influence the amplitude and frequency of pulsations in the column. More than one valve may be connected to one column and more than one column can be connected to one valve. Preferred valve designs are disclosed, as are preferred fluid circuits incorporating surge tank means.
Abstract:
A PROCESS FOR THE SEPARATION OF LOWER BOILING POINT LIQUIDS FROM THOSE OF A HIGH BOILING POINT, AND APPARATUS THEREFOR IS DISCLOSED. THE LIQUID MIXTURE IS SUPPLIED TO THE BASE OF THE EXTRACTOR AND PASSED UPWARDS UNDER CONTROLLED TEMPERATURE AND REDUCED PRESSURE IN THE VAPOR STATE THROUGH SEVERAL TUBES, WHOSE LENGTH IS FROM 15 TO 35 TIMES THEIR DIAMETER; THE VAPOR LEAVES THE TUBES AT A
VELOCITY APPROACHING THE VELOCITY OF SOUND IN THE VAPOR, AND IS SUBSEQUENTLY CONDENSED. THE LOWER BOILING LIQUID THUS RECOVERED IS OF HIGH PURITY, OFTEN REPRESENTING UP TO 90% OF THE TOTAL LOWER BOILING FRACTION OF THE MIXTURE ENTERING THE EVAPORATOR.
Abstract:
Laurolactam is purified by crystallization from solution in a solvent mixture of acetonitrile and water. The water content of the solvent mixture does not exceed 45 percent. Laurolactams thus purified are useful in the preparation of polyamides.
Abstract:
In order to dislodge our bubbles from particles e.g. cut cylindrical fibers, as they enter a confined liquid body through a surface, a small portion of the liquid body near the surface is vibrated and the particles are funneled into the liquid body through the surface by means calculated to subject each particle to about the same amount of vibration. By preference this includes funneling the particles onto the central region of a submerged, perforated plate. The particles vibrate to the periphery of the plate and fall into the gap between the plate and the confining walls of the liquid body. In a counter current liquid extraction system, liquid may pass up through the plate perforations.
Abstract:
POLYAMIDE SULPHOXIDES ARE PREPARED BY OXIDIZING POLYAMIDES COMPOSED OF MONOMER UNITS HAVING THE FORMULA (-NH-CO-(CH2)2-S-(CH2)3-) WITH AN AQUEOUS SOLUTION OF HYDROGEN PEROXIDE AT ABOUT ROOM TEMPERATURE. POLYAMIDE ARTICLES WHICH HAVE BEEN TREATED ACCORDING TO THE PROCESS OF THE PRESENT INVENTION HAVE VEEN FOUND TO HAVE SUBSTANTIALLY REDUCED SURFACE CHARGE.
Abstract:
A PROCESS AND APPARATUS ARE DISCLOSED FOR THE PREPARATION OF HIGH-MOLECULAR-WEIGHT POLYMERIZATION PRODUCTS BY IONOGENIC CATALYTIC POLYMERIZATION OF LACTAMS, IN WHICH ONE PORTION OF THE MONOMER IS MIXED WITH A CATALYST AND ANOTHER PORTION WITH A PROMOTER FOR ACDELERATING THE POLYMERIZATION, AFTER WHICH THESE TWO COMPONENTS ARE MIXED IN THE LIQUID STATE AND INTRODUCED INTO A HEATED MOULD IN WHICH THE POLYMERIZATION TAKES PLACE.
Abstract:
A process of preparing protein by cultivating protein-rich Eumycetes, wherein a mixture of aliphatic mono- and dicarboxylic acids with fewer than 8 carbon atoms is used as a carbon source in a culture medium with a pH between 5.5 and 8.
Abstract:
A balance having a rotatably suspended balance arm connected to a horizontally disposed tension wire; the tension wire is mechanically linked to a barrel-shaped coil holder which is rotatably mounted in a casing; a permanent magnet is fixed to the casing to extend within the coil holder; conducting coils are arranged on the exterior of the coil holder to cooperate with the magnets to restore the balance arm to an equilibrium position; the current supplied to the coils to restore the balance arm being a measure of the weight of the object placed on the balance arm.