Systems and processes for polymer production

A method for producing a polypropiolactone composition, comprising:

• combining beta propiolactone and at least one salt of a compound of Formula (III) to produce the polypropiolactone composition, wherein:
• the compound of Formula (III) has the structure:
• wherein p is independently an integer from 0 to 9;
• the at least one salt of the compound of Formula (III) independently comprises:
• an anion of the compound of Formula (III), and
• a cation selected from the group consisting of quaternary ammonium, protonated amine, iminium, guanidinium, phosphonium, phosphazenium, sulfonium, arsonium, and a cation of a nitrogen-containing heterocycle, or any combination thereof;
• and
• the polypropiolactone composition comprises polypropiolactone polymers, or salts thereof, independently comprising:
• (a) an acrylate end group having the structure
• and
• (b) a polymer chain comprising repeating units having the structure
• wherein the acrylate end group caps the alkyl terminus of the polymer chain, and wherein:
• (1) the polypropiolactone composition has an Mn less than or equal to about 40,000 g/mol;
• and
• (2) the polypropiolactone composition has a polydispersity less than or equal to about 2.0;
• and
• (3) at least 90 wt % of the polypropiolactone composition comprises polypropiolactone polymers, or salts thereof, having the acrylate end group.