摘要:
The invention refers to a method for producing expanded polymer pellets, which comprises the following steps: melting a polymer comprising a polyamide; adding at least one blowing agent; expanding the melt through at least one die for producing an expanded polymer; and pelletizing the expanded polymer. The invention further concerns polymer pellets produced with the method as well as their use, e.g. for the production of cushioning elements for sports apparel, such as for producing soles or parts of soles of sports shoes. A further aspect of the invention concerns a method for the manufacture of molded components, comprising loading pellets of an expanded polymer material into a mold, and connecting the pellets by providing heat energy, wherein the expanded polymer material of the pellets or beads comprises a chain extender. The molded components may be used in broad ranges of application.
摘要:
The invention refers to a method for producing expanded polymer pellets, which comprises the following steps: melting a polymer comprising a polyamide; adding at least one blowing agent; expanding the melt through at least one die for producing an expanded polymer; and pelletizing the expanded polymer. The invention further concerns polymer pellets produced with the method as well as their use, e.g. for the production of cushioning elements for sports apparel, such as for producing soles or parts of soles of sports shoes. A further aspect of the invention concerns a method for the manufacture of molded components, comprising loading pellets of an expanded polymer material into a mold, and connecting the pellets by providing heat energy, wherein the expanded polymer material of the pellets or beads comprises a chain extender. The molded components may be used in broad ranges of application.
摘要:
A polyacetal resin composition makes it possible, when formed into a molded article, to minimize deterioration during contact with sulfur-containing fuel or an acidic detergent. The polyacetal resin composition contains (A) 100 parts by weight of polyacetal resin, (B) 0.1-1.0 parts by weight of hindered phenolic antioxidant, (C) 0.1-2.0 parts by weight of alkaline earth metal oxide, (D) 0.5-3.0 parts by weight of polyalkylene glycol, and (E) 0.01-1.0 parts by weight of polyvalent fatty acid full ester. This polyacetal resin composition minimizes reductions in the weight of a molded article even after the molded article has been immersed in sulfur-containing fuel.
摘要:
The invention refers to a method for producing expanded polymer pellets, which comprises the following steps: melting a polymer comprising a polyamide; adding at least one blowing agent; expanding the melt through at least one die for producing an expanded polymer; and pelletizing the expanded polymer. The invention further concerns polymer pellets produced with the method as well as their use, e.g. for the production of cushioning elements for sports apparel, such as for producing soles or parts of soles of sports shoes. A further aspect of the invention concerns a method for the manufacture of molded components, comprising loading pellets of an expanded polymer material into a mold, and connecting the pellets by providing heat energy, wherein the expanded polymer material of the pellets or beads comprises a chain extender. The molded components may be used in broad ranges of application.
摘要:
A process for recycling polyoxymethylene polymers is disclosed. A polyoyxmethylene polymer is at least partially dissolved in an aprotic compound. The resulting solution or suspension (liquid mixture) is then contacted with a catalyst which causes the polyoxymethylene polymer to be converted into a cyclic acetal. The cyclic acetal can be separated, collected and used in other processes. In one embodiment, the cyclic acetal may be used to produce a polyoxymethylene polymer.
摘要:
A process for producing cyclic acetals is described. A formaldehyde source is contacted with an aprotic compound in the presence of a catalyst to produce the cyclic acetals. The aprotic compound can increase conversion rates and/or efficiency. In one embodiment, the formaldehyde source is obtained from methanol. In particular, methanol can be converted into formaldehyde which is then converted into a cyclic acetal. In one embodiment, the cyclic acetal can then be used to produce oxymethylene polymers.
摘要:
A process is described for producing plastics composites comprising a polyacetal molding, onto part or all of at least one surface of which a molding or a coating composed of thermoplastic has been directly molded. The process encompasses the following measures: i) production of a polyacetal molding ii) treating at least one predetermined portion of one of the surfaces of the polyacetal molding with an atmospheric, potential-free plasma, and iii) single or multiple molding-on of the thermoplastic to at least one part of the surface treated with the atmospheric, potential-free plasma. Instead of the polyacetal molding, the molding composed of thermoplastic may be produced first, the polyacetal molding being molded onto this after the plasma treatment. The process can produce polyacetal composites in particular with thermoplastic elastomers, and these feature good adhesion.
摘要:
Polyacetal articles are etched to prepare the surface for subsequent treatments, in particular plating and painting, by immersing the articles in a mixed acid bath containing the following four acids and water in the following quantities and proportions: 28 to 39 weight % of sulfuric acid and 25 to 32 weight % of phosphoric acid, wherein the ratio by weight of sulfuric acid to phosphoric acid is in the range from 0.9 to 1.5; 3 to 10 weight % hydrochloric acid and 3 to 14 weight % acetic acid, wherein the ratio by weight of hydrochloric acid to acetic acid is in the range 0.25 to 3.0; and to 41 weight % water; at a temperature in the range 25-35null C. for a duration of up to 60 minutes. This etching process has a wider processing window than prior art processes.
摘要:
Oxymethylene polymers are obtained in a granular form by cooling a solution or dispersion of an oxymethylene polymer, the temperature of which solution or dispersion is above the sintering temperature of the oxymethylene polymer, to a temperature just below the sintering temperature of the oxymethylene polymer. As dissolving or dispersing agent as well as precipitating and cooling agent there is used a mixture of methanol and water having a methanol content of at least 75% by weight. The oxymethylene polymer obtained is suitable as engineering plastic for preparing moulded articles.
摘要:
Thermoplastic molding compositions of polyoxymethylene, glass fibers and adhesion promoting substances. The adhesion promoters used are polymeric organosilanes. The molding compositions show improved toughness and strength properties.