摘要:
A multilayer film which comprises the following layers: I. an upper layer composed of a polyamide molding composition which is transparent at the selected layer thickness, and II. a lower layer composed of a polyamide molding composition which comprises the following components: a) from 70 to 99% by weight of a polyamide selected from α) polyamides that can be prepared from lactam monomers or from the corresponding ω-aminocarboxylic acids having 6, 7, 8, 9, 10, 11, or 12 carbon atoms, β) polyamides based on diamine and dicarboxylic acids, in each case having from 6 to 18 carbon atoms, γ) polyamide elastomers that can be prepared from oligomeric, difunctional units based on one of the polyamides mentioned under α) and β), and on a difunctional oligoalkylene glycol, δ) copolyamides that can be prepared from the following components: from 50 to 99.9 mol % of a lactam monomer or of the corresponding ω-aminocarboxylic acid having 6, 7, 8, 9, 10, 11, or 12 carbon atoms, or of a substantially equimolar mixture composed of a linear aliphatic diamine and of a linear aliphatic or aromatic dicarboxylic acid in each case having from 6 to 18 carbon atoms, and from 0.1 to 50 mol % of the combination of a diamine and a dicarboxylic acid, where either the diamine or the dicarboxylic acid or both differ from the diamine used, if appropriate, in the other component and, respectively, the dicarboxylic acid used, if appropriate, in the other component, or of another lactam; b) from 1 to 30% by weight of a copolymer which contains units of the following monomers: α) from 20 to 94.5% by weight of one or more α-olefins having from 2 to 12 carbon atoms, β) from 5 to 79.5% by weight of one or more acrylic compounds, γ) from 0 to 50% by weight of an olefinically unsaturated epoxide, carboxylic anhydride, carboximide, oxazoline, or oxazinone has good printability and adhesive-bondability and transparency, and can be used, for example, as an overcoating for skis.
摘要:
A molding composition which comprises the following components: a) a semicrystalline copolyamide and b) an effective amount of a crystallization aid selected from nanoscale fillers and metal salts, metal oxides, or metal hydroxides which can react with the carboxy end groups of the copolyamide, where the copolyamide can be prepared from the following monomer combination: α) from 50 to 99 mol % of a lactam or of a corresponding co-aminocarboxylic acid having 8, 9, 10, 11, or 12 carbon atoms or of a substantially equimolar mixture composed of a diamine and of a dicarboxylic acid, where the diamine has been selected from the group of 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,10-decamethylenediamine, and 1,12-dodecamethylenediamine, and the dicarboxylic acid has been selected from the group of sebacic acid and 1,12-dodecanedioic acid, and β) from 1 to 50 mol % of a substantially equimolar mixture composed of a diamine and of a dicarboxylic acid, where either the diamine or the dicarboxylic acid or both differ from the diamine used, if appropriate, under α) and, respectively, the dicarboxylic acid used, if appropriate under α), or of another lactam and, respectively, ω-aminocarboxylic acid, is transparent and has good processability, and gives good results in decoration by means of screen printing.
摘要:
A process for producing moldings with condensing-up of a polyamide molding composition whose polyamide component contains, as a result of the method of preparation, at least 5 ppm of phosphorus in the form of an acidic compound by means of a compound having at least two carbonate units, wherein a) from 0.001 to 10% by weight, based on the polyamide, of a salt of a weak acid is added to the polyamide molding composition prior to compounding or during compounding, b) a mixture of the finished composition and the compound having at least two carbonate units is prepared, c) the mixture is, if appropriate, stored and/or transported and d) the mixture is subsequently processed to produce the molding, with the condensing-up occurring only in this step, effects a significant increase in the melt stiffness combined with moderate processing presssures, which considerably simplifies, in particular, the production of hollow bodies and hollow profiles having large diameters.
摘要:
A process for producing moldings with condensing-up of a polyamide molding composition by means of a compound having at least two carbonate units, wherein a) a polyamide molding composition is made available, b) a mixture of the polyamide molding composition and the compound having at least two carbonate units is prepared, c) the mixture is, if appropriate, stored and/or transported and d) the mixture is subsequently processed to produce the molding, with the condensing-up occurring only in this step, and the molding is a hollow body or hollow profile having an external diameter of at least 30 mm and a wall thickness of at least 1 mm, effects a significant increase in the melt stiffness combined with moderate processing presssures, which considerably simplifies the production of these moldings.
摘要:
Liquid melts of dicarboxylic acid have a tendency to undergo unwanted discoloration on prolonged storage. By means of a solution of the dicarboxylic acids in a lactam of an aliphatic .alpha.,.omega.-aminocarboxylic acid, the discoloration can be avoided.
摘要:
A moulding composition contains at least 40 wt % of components a) and b). Based on the sum of components a) and b), there are 60-99 wt % of component a) and 40-1 wt % of component b). Component a) is a partially aromatic copolyamide containing, as polymerized monomer units, 30-90 mol % of a combination of hexamethylenediamine and terephthalic acid and 70-10 mol % of a combination of hexamethylenediamine and a linear aliphatic dicarboxylic acid having 8-19 C atoms. Component b) is an olefinic copolymer containing, as polymerized monomer units, i) 35-94.9 wt % of ethene-based monomer units, ii) 5-65 wt % of monomer units based on a 1-alkene having 4-8 C atoms, iii) 0-10 wt % of monomer units based on an olefin different from i) and ii), and iv) 0.1-2.5 wt % of monomer units based on an aliphatically unsaturated dicarboxylic acid anhydride, where the sum of wt % of i), ii), iii) and iv) is 100%.
摘要:
A metallic pipe for contact with a hydrolyzing medium provides longer operating times and improved high temperature resistance. The pipe contains a layer of a polyamide moulding composition containing at least 50% by weight of polyamide content containing: I) 60 to 98 parts by weight of a polyamide which contains 10 to 70 meq/kg of a terminal carboxy group and has a relative solution viscosity ηrel of at least 1.90, and II) 2 to 40 parts by weight of a polyamine-polyamide graft copolymer produced from: a) 0.5 to 25% by weight, based on the entire monomer mixture, of a polyamine having at least 4 nitrogen atoms, and b) 75 to 99.5% by weight, based on the entire monomer mixture, of polyamide-forming monomers selected from lactams, ω-aminocarboxylic acids and/or equimolar combinations of diamine and dicarboxylic acid, with the proviso that the amino group concentration of the graft copolymer is in the range from 100 to 2500 meq/kg, wherein the sum of the parts by weight of I) and II) is 100.
摘要:
A polyamide molding composition is condensed up in the melt by means of a masterbatch containing a compound having at least two carbonate units and also a polyetheramide in which at least 50% of the end groups are present as amino end groups, whereupon the melt mixture is discharged and solidified to give a molding composition or a molding. The product obtained has an increased amino end group content and consequently an improved hydrolysis resistance.
摘要:
A process for producing moldings with condensing-up of a polyamide molding composition whose polyamide component contains, as a result of the method of preparation, at least 5 ppm of phosphorus in the form of an acidic compound by means of a compound having at least two carbonate units, wherein a) from 0.001 to 10% by weight, based on the polyamide, of a salt of a weak acid is added to the polyamide molding composition prior to compounding or during compounding, b) a mixture of the finished composition and the compound having at least two carbonate units is prepared, c) the mixture is, if appropriate, stored and/or transported and d) the mixture is subsequently processed to produce the molding, with the condensing-up occurring only in this step, effects a significant increase in the melt stiffness combined with moderate processing pressures, which considerably simplifies, in particular, the production of hollow bodies and hollow profiles having large diameters.
摘要:
The invention provides a process for preparing linear alpha,omega-dicarboxylic diesters by reacting a triglyceride containing fatty acid residues having monounsaturated or polyunsaturated carbon chains with carbon monoxide, an acid and an OH-group donor in one reaction step in the presence of a catalyst.