Interpolymer resin particles comprised of 20% to 80% by weight polyolefin,
e.g. polyethylene and 80% to 20% by weight of an in situ polymerized vinyl aromatic
resin, e.g. polystyrene or poly(styrene-butyl acrylate) and forming an interpenetrating
network of polyolefin and vinyl aromatic resin particles. The interpolymer particles
are impregnated with a volatile hydrocarbon blowing agent, and limonene, e.g. d-limonene,
ranging from about 0.1 to about 5 parts, preferably 0.1 to 1 part by weight, based
on 100 parts by weight of the interpolymer particles, for improved expandability
and a pleasant fragrance.
