polybutylene
[ pol-ee-byoot-l-een ]
/ ˌpɒl iˈbyut lˌin /
noun Chemistry.
any of several polymers of butylene, used chiefly in the manufacture of lubricants and synthetic rubber.
Also
pol·y·bu·tene
[pol-ee-byoo-teen] /ˌpɒl iˈbyu tin/.