polybutylene vs polybutene

polybutylene and polybutene both are nouns.

Word	Noun	Adjective	Verb	Adverb
polybutylene	Yes	No	No	No
polybutene	Yes	No	No	No

As nouns, polybutylene and polybutene are synonyms defined as:

polybutylene and polybutene: a polymer of butylene; used in lubricants and synthetic rubber

polybutylene (noun)	polybutene (noun)
a polymer of butylene; used in lubricants and synthetic rubber	a polymer of butylene; used in lubricants and synthetic rubber