Practicing Grammar and pronunciation with a text excerpt from a book on Plastic recycling - a little something for my Dear engineering students
Just a few notes:
1. Sentence one: The "not" following the conjunction "and" is not part of the second prep phrase that is functioning as adverbial (the one that's located at the end of the first sentence). We have here a case of ellipsis. This is what the sentence would sound like without the ellipsis: "Polymers are stabilized only for processing and first lifetime of use and they are not stabilized for processing and second lifetime of use." This version helps you see that the adverb "not" is part of the verb phrase, not part of the prep phrase - and it's not a sentence adverbial either.
2. The relative clause at the end of the second sentence is a bit unfortunate, I think. It modifies the noun phrase "plastic film packaging material made out of polyolefins," which is of course dreadfully long to start with and also ends with a plural word (which is, however, not the head of the phrase). Since the head of this long noun phrase, "material," is a singular noun, the verb in the relative clause is (and must be) a singular verb form. But there are all these plurals in between the head noun and its modifying non-restrictive relative clause, and these put the reader into a sort of plural mood. Add to this problem that there is the inserted prep phrase, which provides more details but also creates even more distance between the head noun and its non-restrictive post-modifier. In short, I would have preferred a different construction here because I find the one at hand quite hiccupy.
3. Two notes on pronunciation:
The first note relates to the IPA versions. The forms provided in parentheses are either the weak forms of the preceding words or they are alternative pronunciation options.
The second note relates to the pronunciation of the gerund "processing."
In the noun "process" (which is stressed on the first syllable), the vowel of the second syllable is usually the half-open front vowel /e/ that occurs in the color /red/, like so:
AmE: /ˈprɑːses/&/ˈproʊses/ and BrE /ˈprəʊses/. (But with some speakers and in some situations, this front vowel is reduced to the unstressed central vowel schwa /ə/.)
The corresponding verb "process" is often pronounced the same way, although the front vowel /e/ is more easily reduced to a schwa /ə/. And the same can happen for the gerund and participle.