Abstract: Process for recovering .alpha.-aminoalcohols by extraction from aqueous solutions, in which process an aromatic aldehyde is added at elevated pH to an aqueous solution of an aminoalcohol in an at least equimolar amount in respect of the aminoalcohol, the resulting mixture is converted with formation of the Schiff base of the aldehyde and the aminoalcohol and the aqueous solution is subsequently extracted using a water-immiscible organic solvent, upon which the Schiff base in the resulting extract is hydrolized and the .alpha.-aminoalcohol or a salt thereof is recovered.
Type:
Grant
Filed:
September 19, 1990
Date of Patent:
February 11, 1992
Assignee:
Stamicarbon B.V.
Inventors:
Wilhelmus H. J. Boesten, Catharina H. M. Schepers, Mathieu J. A. Roberts
Abstract: The invention relates to a composition containing UV curable unsaturated monomers and/or oligomers, a photoinitiator and colloidal silica with an organosilane compound, a polyalkoxysilane being used as organosilane compound and the composition containing an acid catalyst.
Abstract: The invention relates to a polyamide composition comprising tetramethylene adipamide, tetramethylene-terephthalamide and tetramethylene isophthalamide units. the polyamide composition has a melting temperature in the same order as the homopolymer tetramethylene adipamide, a comparable crystallinity but very improved melt stability and stiffness.
Abstract: A process for the manufacture of filaments, tapes and films that possess a shish kebab morphology. This is effected in that for instance UHMW PE after extrusion is stretched at a temperature between the melting temperature (Tm) and a critical temperature (Tc) and subsequently cooled in stressed condition. The stretching rate is between 0.1 and 10 sec..sup.-1.
Type:
Grant
Filed:
June 2, 1989
Date of Patent:
January 14, 1992
Assignee:
Stamicarbon B.V.
Inventors:
Cornelis W. M. Bastiaansen, Henricus E. H. Meijer, Zaheer Bashir
Abstract: The invention relates to new pure D- or L-N-hydroxy-alpha-amino acids and the derivatives thereof, including optically active N-hydroxy-phenylglycine amide, which has antibiotic and antitumor activity.
Type:
Grant
Filed:
November 1, 1989
Date of Patent:
December 10, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Johan Kamphuis, Wilhelmus H. J. Boesten
Abstract: A flame retardant polyamide composition including flame retardant effective amounts of (a) an iron compound and (b) a char forming thermoplastic polymer having aromatic groups in the backbone. A char stabilizing compound (c) may also be present. In a preferred embodiment (b) is a polyphenylene ether. In a preferred embodiment, (c) is anhydrous zinc borate or a wollastonite.
Type:
Grant
Filed:
August 3, 1990
Date of Patent:
December 10, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Edward D. Weil, Navin G. Patel, Robert M. Leeuwendal
Abstract: New polymer composition which has excellent thermal stability, good impact resistance and processability, containing the following compounds:a) 20-75 wt. % of a graft copolymer which contains 10-90 wt. % rubber and grafted on the rubber a copolymer of acrylonitrile and styrene or .alpha.-methylstyreneb) 6-50 wt. % of a copolymer of styrene or .alpha.-methylstyrene containing 20-32 wt. % maleic anhydride, with a molecular weight of 50,000-500,000c) 5-70 wt. % polyamide andd) 0-30 wt. % of a copolymer of styrene or .alpha.-methylstyrene and acrylonitrile.
Type:
Grant
Filed:
August 10, 1989
Date of Patent:
December 10, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Herman A. J. Schepers, Wilhelmus A. M. Debets
Abstract: Novel gel-spun, irradiated and drawn ultra high strength high molecular weight and at least partially cross-linked and/or branched polyethylene filaments, tapes and films, exhibiting a combination of substantially lower creep rates, very high heat shrink characteristics and high abrasion resistance properties than corresponding but non-irradiated articles, and with a process for making the same.
Abstract: The invention relates to polyethylene compositions comprising 20-98 wt % branched polyethylene a) with a density of between 915 and 940 kg/m.sup.3 and a melt flow index of between 0.05 and 40 dg/minute, prepared by a high pressure radical process, and 2-80 wt % substantially linear polyethylene b) with a density of between 850 and 915 kg/m.sup.3, a melt flow index of between 0.05 and 25 dg/minute and a DSC crystallinity at 23.degree. C. of at least 10%, prepared with the aid of a transition metal catalyst, the difference between the highest crystallization temperature of branched polyethylene a) and the highest DSC crystallization temperature of linear polyethylene b) being at most 10.degree. C. and the mixture having modulus of elasticity of at most 280 N/mm.sup.2 and objects made therefrom. These polyethylene compositions, when processed to foamed objects, have a high resistance to high temperatures ss well as a high flexibility.
Abstract: A continuous process for separating hydrogen in high purity from a gaseous hydrogen-containing mixture by absorbing in an absorber unit the hydrogen by metal hydride forming particles suspended in an inert liqid and desorbing in a desorber unit the hydrogen from the hydrided particles includes the step of treating the suspension of the hydrided particles before entering the desorber unit to remove dissolved gaseous non-hydrogen components by stripping with hydrogen, preferably with a part of desorbed hydrogen. By this way it is possible to obtain hydrogen having a purity of more than 99.9%.
Abstract: The invention is related to blow-molded nylon products comprising 40-95 parts by weight nylon 46, 3-40 parts by weight nylon 6, nylon 66 and/or nylon 6/66 and 2-40 parts by weight of an acid or epoxy modified polyolefin. Blow moldability and impact resistance are improved without deterioration of high temperature resistance and mechanical strength.
Abstract: The invention relates to a resin composition based on a polymer and an ester of an unsaturated fatty acid and an alchol containing a terminal unsaturation. The resin composition contains as ester a compound with the formula: ##STR1## where: R.sup.1 is an alkylene radical with 10-24 carbon atoms and at least one non-terminal ethylenically unsaturated bond andR.sup.2 is a derivative of an organic group comprising one or more terminal allylether groups.The resin composition is preferably substantially 100%-solid.
Abstract: A process for the condensation of imides and alcohols or amines to ester acyl lactams, ester amide acyl lactams or amide acyl lactams by reacting a polyol or polyamine in the liquid phase with an acyl lactam compound is disclosed.
Type:
Grant
Filed:
April 12, 1990
Date of Patent:
October 22, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Christiaan Schroder, Albert A. Van Geenen, Josefina M. A. Schiffer
Abstract: The invention relates to a process for racemizing an optically active N-benzylidene amino-acid amide, characterized in that a solution of the N-benzylidene amino-acid amide is mixed in a water-miscible organic solvent with at least 0.05 mole strong base per liter solution.The invention further relates to a process for preparing an L-amino acid by enzymatic separation of the corresponding DL-amino-acid amide with an enzyme preparation from Pseudomonas putida, in which process also uncoverted D-amino-acid amide is left behind in solution, characterized in that benzaldehyde is added to the solution, during which addition a precipitate of D-N-benzylidene amino-acid amide is being formed, this precipitate is subsequently, after being separated off, dissolved in an acetone-water mixture, 0.08-0.15 mole KOH/liter solution is subsequently added, the resulting solution is stirred for 1-20 hours at 20.degree.-60.degree. C.
Type:
Grant
Filed:
April 3, 1989
Date of Patent:
September 10, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Wilhelmus H. J. Boesten, Hans E. Schoemaker, Bernardus H. N. Dassen
Abstract: An impact resistant resin composition comprising from 30 to 70% (wt) of a polyamide with at least 40 mol/10.sup.6 g amino groups, from 5 to 40% (wt) of a polyarylate, from 5 to 40% by weight of the adduct of an unsaturated dicarboxylic acid anhydride and a butadiene copolymer with at least one monomer from the group of aromatic vinylmonomer, an unsaturated nitrile monomer and an acrylate monomer, and from 3 to 30% (wt) of an epoxy group-containing olefine copolymer obtained by copolymerizing at least one unsaturated glycidyl monomer with at least one unsaturated olefin monomer.
Type:
Grant
Filed:
July 2, 1990
Date of Patent:
August 27, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Kenji Yasue, Takeshi Marutani, Yasumasa Fukushima, Takashi Ida
Abstract: The invention relates to an object and a process for the preparation of an object from an ethylene-vinyl alcohol copolymer with high tensile strength and modulus, by converting:a) a solution of an ethylene-vinyl alcohol copolymer with a weight-average molecular weight above 6.times.10.sup.4 kg/Kmole into a shaped, solvent-containing object in a suitable solvent or mixture of solvents;b) converting this object into a gel object with a homogeneous gelstructure by rapid cooling to below the gelation temperature;c) removing the solvent present in this gel object for the most partd) Drawing the gel object during or after solvent removal at a temperature above the glass transition temperature but below the melting temperature of the copolymer.
Abstract: The invention relates to combinations of polymer filaments or yarns of high tensile strength, high modulus and low coefficients of friction and filaments or yarns of high coefficients of friction. Combinations of this type, which have been produced in particular by core spinning the filaments or yarns of low coefficient of friction with filaments or yarns of high coefficients of friction or by twisting the two filament or yarn components, are suitable in particular for producing bulletproof wovens, knits and nonwovens.
Abstract: Ballistic structure comprising a solid combination of a metal first layer and a second layer consisting of a composite fiber material containing fibers with a tensile strength of at least 2 GPa and a modulus of at least 20 GPa, based on polyethylene with a weight average molecular weight of at least 4 * 10.sup.5 and a thermoplastic binding agent shows good ballistic properties if a binding layer is applied between the first layer and the second layer, which binding layer contains a modified polyolefin.
Type:
Grant
Filed:
May 5, 1989
Date of Patent:
July 30, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Peter Bruinink, Wilhelmus A. R. M. Pessers
Abstract: The invention relates to a resin composition comprising a mixture of resins, a first resin of which consists of the reaction product of an epoxidized fatty acid ester of a polyvalent alcohol with a carboxylic acid and a second resin consists of an ester of a polyvalent alcohol, modified with carboxylic acid.The resin mixture, contains an unsaturated polyester resin having a molecular weight of 1200-20,000 per double bond and an acid number of 5-50, from about 50% to about 90% of the unsaturation being formed by a semi-ester of an .alpha.,.beta.-unsaturated dicarboxylic acid.
Type:
Grant
Filed:
January 3, 1990
Date of Patent:
June 25, 1991
Assignee:
Stamicarbon B.V.
Inventors:
Paulus J. H. M. Smeets, Caspar G. M. Paas, Willem P. M. Kraanen
Abstract: The invention relates to graft-modified linear polyethylene with low density (<940 kg/dm.sup.3) (LLDPE), and in particular with very low density (density<915 kg/dm.sup.3), (VLDPE) grafted particularly with styrene/maleic anhydride.These polyethylenes are very good impact modifiers with a high UV resistance and a high degree of toughness and do not cause discolouration of the polyamides and polyesters modified with them. They can be prepared in a simple and economically efficient manner with a high degree of conversion.These polyethylenes are also highly suited as impact modifiers, adhesives or adhesive layers, heat-seal layers, bonding layers in composite films, compatibility enhancement agents as well as bonding promotors, or as components of such agents or layers.Graft-modified polyethylene can be prepared by converting a linear low-density polyethylene with the grafting material at a temperature higher than 110.degree. C.