Polymer mixt. for prodn. of articles such as refrigerator linings and foams consists of (I) a matrix of polymers prepd. from 90 wt.% aromatic vinyl monomers, the polymers having an average mol. wt. of 50,000-500,000 esp. 100,000-300,000, (II) polymers prepd. from =60 esp. 90 wt.% conjugated dienes, 0-40 wt.% aromatic mononuclear, monovinyl cpds. and 0-10 wt.% other alkenically unsatd. monomers with is not 3 wt.% non-conjugated difunctional unsatd. cpds. the av. mol.wt. of these polymers being is not 100,000 esp. 250,000-500,000, and (III) block copolymers of the ABA type in which each A segment is compatible with I, and each B segment is compatible with II, and the wt. ratio of A to B is 45:55 to 60:40, the copolymer having an av mol.wt. of =150,000 esp. 200,000-300,000, and two main glass transition temps. between -90 degrees C and 90 degrees C. Components II and III are dispersed in component I in the form of micelles with a max. dimensions of 0.2-5 mu; I and II are present in a molar ratio of =1:1 esp. 2:1-5:1; I and II are sufficiently incompatible to give a finished mixt. showing the glass transition temps. of both components. The mixt. contains 3-25 esp. 5-15 wt.% III, and the total content of aromatic, mononuclear monovinyl monomer units in the three components is 75-95 wt.%.
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