Adhesive compositions are described which comprise at least one organic
sulfoxide, sulfone or sulfide and at least one ketone, ether, ester,
amide or carbonate or a mixture thereof. The adhesive compositions also
may contain one or more water insoluble polymers such as ABS, PVC and
CPVC. Methods of adhesively bonding or welding a first plastic surface to
a second plastic surface using these adhesive compositions also are
described.