摘要:
Expandable molding compositions having high heat distortion resistance and containing from 80 to 99% by weight of a styrene polymer, 1 to 20% by weight of poly-1,4-phenylene sulfide, from 1 to 10% by weight of a C.sub.3 -C.sub.6 -hydrocarbon as blowing agent and, if desired, customary additives, are obtained by suspension polymerization of a solution of the polyphenylene sulfide in styrene.
摘要:
An oil-resistant, expandable styrene polymer containsa) from 10 to 90% by weight of uncrosslinked polystyrene and/or an uncrosslinked styrene copolymer containing at least 50% by weight of copolymerized styrene,b) from 10 to 90% by weight of a crosslinked styrene polymer which contains at least 0.1% by weight, but less than 2% by weight, of a copolymerized monomer having at least two olefinic double bonds,c) from 1 to 10% by weight, based on the sum of a) and b), of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent, and, if desired,d) conventional additives in effective amounts,the mixture of a) and b) having a melt flow index MFI (200.degree. C., 5.0 kp) in accordance with DIN 53 735 of from 1 to 20 [g/10 min].
摘要:
Bead-form expandable styrene polymers containing a styrene polymer having a mean molecular weight (weight average) of less than 130.multidot.10.sup.3 and a steep high-molecular-weight flank of the molecular-weight distribution curve, and 0.15 to 1.5 mol of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent, and, if desired, customary additives in effective amounts, are distinguished by a particularly high expansion capacity.
摘要:
Flame-resistant, expandable styrene polymers containing a styrene (co)polymer, from 0.4 to 6% by weight of hexabromocyclododecane having a mean particle size of from 1 to 50 .mu.m, the particles being provided with a firm coating which has a thickness of from 1/100 to 1/10 of the particle diameter and is insoluble in water and styrene, from 1 to 10% by weight of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent, and, if desired, customary additives, are distinguished by a reduced internal water content and can be processed to form foams which have an improved foam structure and high UV stability.
摘要:
Expandable styrene polymers formed from 50 to 83% by weight of polystyrene and from 17 to 50% by weight of styrene-soluble styreneacrylonitrile copolymer having a total acrylonitrile content of not less than 5% by weight, containing from 3 to 10% by weight of a C.sub.3 -C.sub.6 -hydrocarbon with or without customary additives, are notable for high oil resistance and can be prepared by suspension polymerization of a solution of the styrene-acrylonitrile copolymer in styrene.
摘要:
Expandable styrene polymers which contain a C.sub.3 -C.sub.6 -hydrocarbon as a blowing agent, an organic bromine compound as a flameproofing agent and small amounts of ammonium salt and of an organic amine give, on expansion, foams which have a particularly homogenous foam structure and a good heat insulation effect.
摘要:
Expandable styrene polymers containinga) from 80 to 99% by weight of polystyrene,b) from 1 to 20% by weight of a styrene-soluble polymer having a softening point above 140.degree. C.,c) from 3 to 10% by weight, based on the sum of a) and b), of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent, and, if desired, d) conventional additives,the mixture of components a) and b) having a melt flow index MFI 200/5 of from 15 to 30, have high heat distortion resistance and a high capacity for expansion.
摘要:
Expandable styrene polymers which contain from 10 to 90% by weight of a crosslinked styrene-diene copolymer containing from 2 to 45% by weight of the diene, and from 1 to 10% by weight of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent can be processed to give foams which have high resistance to aromatics.
摘要:
In the preparation of expandable styrene polymers by polymerizing styrene, if desired together with up to 50% by weight of other monomers, in aqueous suspension with addition of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent and, if desired, conventional additives in effective amounts before, during or after the polymerization, foaming is reduced if the aqueous phase contains from 0.05 to 0.3% by weight of polyvinylpyrrolidone having a K value of from 100 to 150 as protective colloid.
摘要:
Flame-resistant, expandable styrene polymers containing a styrene (co)polymer, from 0.4 to 6% by weight of hexabromocyclododecane having a mean particle size of from 1 to 50 .mu.m, the particles being provided with a firm coating which has a thickness of from 1/100 to 1/10 of the particle diameter and is insoluble in water and styrene, from 1 to 10% by weight of a C.sub.3 - to C.sub.6 -hydrocarbon as blowing agent, and, if desired, customary additives, are distinguished by a reduced internal water content and can be processed to form foams which have an improved foam structure and high UV stability.