There is provided a foamable poly(vinyl chloride) resin composition which
can remarkably improve an expansion ratio. There is used a foamable
poly(vinyl chloride) resin composition comprising 100 parts by weight of
(A) a poly(vinyl chloride) resin, 0.5 to 30 parts by weight of (B) a
processing aid, and 0.5 to 15 parts by weight of water and 0 to 20 parts
by weight of a thermal decomposition foaming agent as a foaming agent (C),
wherein the processing aid is obtained by adding and polymerizing 0 to 50
parts of a monomer mixture (b) comprising 0 to 50% by weight of methyl
methacrylate, 50 to 100% by weight of at least one monomer selected from
the group consisting of methacrylate excluding methyl methacrylate and
acrylate, and 0 to 20% by weight of a vinyl monomer copolymerizable
therewith, in the presence of a latex of a (co)polymer obtained by
emulsion polymerizing 50 to 100 parts by weight of a monomer mixture (a)
comprising 50 to 100% by weight of methyl methacrylate, 0 to 50% by weight
of a monomer selected from the group consisting of methacrylate excluding
methyl methacrylate and acrylate, and 0 to 20% of a vinyl monomer
copolymerizable therewith in an amount that a total amount of (a) and (b)
is 100 parts by weight.
