摘要:
The present invention relates to an open-cell foam, and to a process for producing this open-cell foam by melting a thermoplastic, or a mixture comprising a thermo-plastic, giving a melt, mixing the melt with at least one blowing agent under pressure, and foaming the melt comprising the blowing agent via extrusion into the free atmosphere, the temperature of the melt during the foaming process being greater than the melt temperature at which a closed-cell foam is formed, and/or adding a pulverulent solid, and/or adding a foreign polymer. The present invention further relates to the use of the foam of the invention for sound deadening or for producing materials by sound deadening.
摘要:
The invention relates to expandable olefin bead polymers which comprise a blowing agent with a boiling point of from −5 to 150° C., selected from the group consisting of alkanes, alkanols, ketones, ethers and esters. The particles are unfoamed and have a bulk density above 500 g/l, and can be foamed to a bulk density below 200 g/l after storage for one hour at room temperature in free contact with the atmosphere. They are prepared by impregnating polyolefin pellets in suspension in a pressure vessel with the blowing agent, cooling the batch below 100° C., reducing the pressure and isolating the particles.
摘要:
A process for preparing expandable particulate styrene polymers wherein from 5 to 50% by weight of expanded graphite and also, if desired, from 2 to 20% by weight of a phosphorus compound, are present as flame retardants, by suspension polymerization of styrene in the presence of the flame retardants.
摘要:
Expandable pelletized styrene polymer materials with at least bi- or multimodal molecular weight distribution, to a process for their preparation, and to use for producing moldable-foam moldings.
摘要:
The invention relates to foam beads of propylene polymers which comprise more than 40% of open cells. They are produced by impregnating propylene polymer minigranules which comprise from 1 to 40% by weight of a cell opener with a volatile blowing agent in aqueous suspension and subsequently decompressing the mixture.
摘要:
A process for the preparation of expandable granules based on polyaryl ether sulfones and/or polyether imides, containing from 5 to 20% by weight of a physical blowing agent, the blowing agent and the polymers being mixed in an extruder and subsequently extruded directly into a medium at less than 40.degree. C., and a process for the production of foams from expandable granules based on polyaryl ether sulfones and/or polyether imides, containing from 5 to 20% by weight of a physical blowing agent, the granules being press molded at from 120.degree. to 250.degree. C. and at a pressure of from 5 to 30 bar to form a sheet, and the sheet being subsequently foamed by reducing the pressure, are described.
摘要:
Expandable pelletized styrene polymer materials with at least bi- or multimodal molecular weight distribution, to a process for their preparation, and to use for producing moldable-foam moldings.
摘要:
A process for the preparation of expandable styrene polymers having a molecular weight Mw of greater than 170,000 g/mol, which comprises conveying a blowing agent-containing styrene polymer melt having a temperature of at least 120° C. through a die plate with holes whose diameter at the die exit is at most 1.5 mm, and subsequently granulating the extrudate, and expandable styrene polymers (EPS) having a molecular weight Mw of more than 170,000 g/mol with 0.05 to 1.5% by weight of internal water.
摘要:
Solid particulate film-coating compositions consisting of a) 40-90% by weight, preferably 40 to 70% by weight, of a polyvinyl alcohol-polyether graft copolymer (component A), b) 10 to 60% by weight, preferably 20 to 45% by weight, of a chromatic or achromatic colorant (component B) c) 0 to 30% by weight of further conventional auxiliaries (component C) where the amount of components A to C adds up to 100% by weight, which are obtained by extrusion of a melt of components A) to C) and subsequent shaping.
摘要:
A process for producing foam beads with low bulk density from thermoplastic polymers, encompassing the stages of a) addition of a blowing agent to a thermoplastic polymer melt, b) cooling and extrusion, through a die, of the polymer melt comprising blowing agent c) cutting of the polymer melt comprising-blowing agent downstream of the die at reduced pressure with foaming to give foam beads where water and a solubilizer are present in the blowing agent, and foam beads obtainable by the process.