polypropylene vs polypropene

polypropylene and polypropene both are nouns.

Word	Noun	Adjective	Verb	Adverb
polypropylene	Yes	No	No	No
polypropene	Yes	No	No	No

As nouns, polypropylene and polypropene are synonyms defined as:

polypropylene and polypropene: a polymer of propylene used as a thermoplastic molding material

polypropylene (noun)	polypropene (noun)
a polymer of propylene used as a thermoplastic molding material	a polymer of propylene used as a thermoplastic molding material