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.
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:
A molding, produced by a layer-by-layer process in which regions of respective polymer pulverulent layers are selectively melted via introduction of electromagnetic energy, where the process employs a powder which comprises at least one homopolyamide prepared via polycondensation of diamines and dicarboxylic acids, wherein the homopolyamide has an enthalpy of fusion of at least 125 J/g and a recrystallization temperature of at least 148° C.
摘要:
Composite particles comprising core particles completely or partially coated with a precipitated polymer, where the d50 median diameter of the core particles is from 3 to 100 μm and wherein the glass core particle material is at least one selected from the group consisting of a solid glass bead, a hollow glass bead, a porous glass bead, and a foamed glass particle. A method to prepare the particles includes dissolution of a polymer in a solvent and precipitation of the polymer in the presence of a suspension of the core glass particles. Further provided is a layer by layer moulding process employing the composite particles and mouldings obtained therefrom.
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.
摘要:
A pulverulent composition that is a powder containing at least one polymer, and at least one flame retardant that contains ammonium polyphosphate, the powder having a maximum particle size of ≦150 μm and a median particle size of from 20 to 100 μm.
摘要:
A polyamide molding composition which can be used for production of a printable or printed item contains a) at most 90 parts by weight of a polyamide obtained from a lactam or from an amino carboxylic acid having at least 10 carbon atoms; and b) from 10 to 100 parts by weight of PA1010, wherein a total of components a) and b) is 100 parts by weight.
摘要:
A moulding compound for joining two mouldings each made of a PA11 and/or PA12 moulding compound contains at least 50% by weight of a polyamide component so chosen that it is preparable from linear aliphatic diamines and dicarboxylic acids and/or lactams or ω-aminocarboxylic acids, there being 11 to 12 carbon atoms present per carboxamide group in the repeating units, and, furthermore, this polyamide component containing not more than 80% by weight of either one of the polyamides PA11 and PA12. With this compound a firm weld is obtained both to a PA11 moulding and to a PA12 moulding.