Abstract:
A synthetic culture medium comprising a polymeric material having an apparent density of 0.01 and 0.5 and a specific surface area of between 2 and 25 m2/g, the polymeric material being in the form of an amorphous fibril. Such polymeric materials include thermoplastic polymers such as film-forming linear super polyamides, film-forming polyesters, vinly polymers, acrylonitrile base polymers, and polyolefins, the fibrils being suitable for use as a culture medium either alone or in combination with soil, sand and the like so as to provide a more readily aeratable mixture. Plant growth is improved by a process utilizing such synthetic culture medium.
Abstract:
THE INVENTION COMPRISES FILAMENTS AND BRISTLES HAVING A BASIS OF A DIORGANOPOLYSILOXANE WHICH COMBINE A KILOMETRIC BREAKING STRENGTH ABOVE 1.25 WITH AN ELONGATION AT BREAK OF AT LEAST 300%. THEY ARE MADE FROM DIORGANOPOLYSILOXANES IN WHICH AT LEAST 60% OF THE ORGANIC SUBSTITUENT GROUPS ARE METHYL AND A SMALL PROPORTION (0.32%) ARE VINYL, BY EXTRUSION FOLLOWED BY STRETCHING, A HEAT TREATMENT TO "VULCANIZE" THE PRODUCTS, A FURTHER STRETCH AND PREFERABLY A FURTHER HEAT TREATMENT. THE PRODUCTS MAY ALSO BE GIVEN A THIRD HEAT TREATMENT WHILE WOUND UP ON A SUPPORT. THE COMPOSITION WHICH IS EXTRUDED CONTAINS, BESIDES THE DIORGANOPOLYSILOXANE, A FILLER, A CROSSLINKING CATALYST, PREFERABLY OF THE FREE RADICAL TYPE, AND OPTIONALLY A PLASTICIZER, ESPECIALLY AN ORGANISICON COMPOUND.
Abstract:
This invention provides a process for producing polyamide-imide filaments which are heat-stable and have high tensile strength by solvent spinning under specified conditions. In a preferred embodiment the polyamide-imide polymers in solution are extruded into filaments and fibers through a spinneret maintained at a temperature between 60* C. and 180* C. heated at a temperature higher than 160* C. up to about 240* C. at a constant length for 2 to 6 hours, and subsequently drawn at a drawing ratio of at least 3:1 at a temperature generally in the range of about 220* C. up to about 420* C.
Abstract:
Textile articles comprise yarns of a synthetic thermoplastic material, especially polyethylene terephthalate, in which the individual filaments comprise alternating zones of increasing and decreasing thickness, the thinner zones having the higher crystallinity index and vica versa; the filaments have a nonspiral three-dimensional crimp, and both they, and the yarn comprising them, have a high apparent volume. The yarn is made by only partially stretching the initial yarn in contact with a crack promoting agent such as an aqueous alcohol, and subsequently giving the yarn, before or after it is made up, a heat treatment while it is in a relaxed state.
Abstract:
HEAT-SEALABLE ELEMENTS COMPRISING A FIBROUS SUPPORT HAVING A COATING OF A MIXTURE OF COPOLYAMIDE, AMINOPLAST RESIN, AND ACID CATALYST ARE USEFUL INTER ALIA IN GARMENT MANUFACTURE.
Abstract:
Continuous filaments of thermoplastic material are provided wherein such filaments contain a helicoidal curling and/or a residual twist couple. The filaments have a cross section which is substantially the shape of a bean, such cross section varying slightly along the length of the filaments. The filaments are produced by a process which comprises creating an initial twist in an individual strand or in an assembly of a number of strands having a high count per strand and a small number of strands per assembly; thermally treating the twisted strands or assembly of strands; blocking such twist at a point; and separating the single strand or assembly of strands at such point and winding them up. Such a process is characterized in that the point of separation of the yarn is located immediately at the outlet of the heat treatment yarns while the yarns are still in a plastic state. The apparatus necessary for carrying out such process comprises a delivery means for providing the yarn by unwinding, means for separating the strands or assembly of strands, means for initiating the twisting, means for heating the twisted yarn, and means for receiving the yarn. Such apparatus can additionally contain drawing means.
Abstract:
Fancy yarns are made by subjecting yarns of a synthetic thermoplastic material, especially polyester yarns, to partial stretching, e.g. by a factor of 1.5-3.5, in contact with an aqueous lower alkanol or other crack-producing agent, followed by a heat relaxation treatment, the said or other heat treatment, or a supplementary stretch, being applied intermittently or to a continuously varying degree. The yarns obtained have a flake appearance and comprise alternating thick and thin portions, the diameters of the thick and thin portions both varying macroscopically, and the thick parts varying in diameter on the microscopic scale, the zones of smallest diameter corresponding to zones of highest crystallinity and orientation. The thin parts may vary in diameter microscopically in an analogous way but with smaller variations, or may be substantially uniform.
Abstract:
A process for producing brilliant thermostable polyamide-imide fibers and such fibers so produced, such process comprising extruding an N-methylpyrrolidone solution of a polymer having a structure characterized by the following linkages:
B. amide linkages of the formula:
C. amide linkages of the formula: - NH - Ar1 - NH-CO-R-COaqueous N-methylpyrrolidone coagulating 1.5 X; wherein Ar1 represents a bivalent aromatic radical, Ar2 represents a trivalent aromatic radical, R represents a bivalent aromatic, aliphatic, cycloaliphatic or arylaliphatic radical, and M represents an alkali or alkaline earth metal, linkages B representing at least 3 percent of the total of linkages A, B and C in an aqueous N-methylpryyolidone coagulating bath; drawing the extruded filaments in air at a rate of at least 1.5 X ; drying the filaments to eliminate N-methylpyrrolidone; and drying the filaments. The filaments obtained are characterized in being brilliant, homogenous, thermostable filaments.
Abstract:
An apparatus for the continuous high speed manufacture of texturized thermoplastic threads employing a fluid which apparatus comprises two assembled blocks of simple geometric form which blocks have therein two conduits in communication with each other. The first of the conduits is constituted by a longitudinal groove extending throughout the entire length of one side of one of the blocks and the second conduit constitutes a groove completely within one side of the other block so that when the blocks are assembled with the conduits facing each other the conduit in the second block is disposed at an angle to the first conduit.
Abstract:
A composite yarn comprising hexamethylene diamonium polyadipate or polyhescamethylene adipamide and a copolyamide prepared from hexamethylene diamonium adipate and a salt derived from a diacid containing six to 12 carbon atoms and a cycloalkane diamine has a latent crimp and is suitable for use in the manufacture of woven fabrics, knitted fabrics or carpets.