A method for producing polypropiolactone (PPL), comprising: providing feedstock streams of ethylene oxide (EO) and carbon monoxide, wherein the feedstock streams are optionally combined; directing the feedstock streams to a first reaction zone; contacting the feedstock streams with a carbonylation catalyst in the presence of a carbonylation solvent in the first reaction zone to convert at least a portion of the EO to a beta propiolactone (BPL) product stream, wherein the BPL product stream comprises BPL, carbonylation catalyst, and carbonylation solvent, and wherein the reaction of converting at least a portion of the EO to a beta propiolactone (BPL) product stream is a continuous reaction; separating at least a portion of carbonylation catalyst from the BPL product stream to produce a carbonylation catalyst recycling stream and a processed BPL product stream, wherein the processed BPL product stream comprises BPL and carbonylation solvent; directing the processed BPL product stream to a carbonylation solvent removal zone; removing at least a portion of the carbonylation solvent from the processed BPL product stream to produce a polymerization feed stream, wherein the polymerization feed stream comprises BPL; directing the polymerization feed stream to a second reaction zone; contacting BPL in the polymerization feed stream with a polymerization catalyst in the second reaction zone to produce PPL; and further comprising introducing a polymerization solvent into the polymerization feed stream, prior to contacting the polymerization feed stream with the polymerization catalyst, wherein the polymerization solvent is different from the carbonylation solvent, and wherein the conversion of BPL to PPL is performed in a continuous flow format. providing feedstock streams of ethylene oxide (EO) and carbon monoxide, wherein the feedstock streams are optionally combined; directing the feedstock streams to a first reaction zone; contacting the feedstock streams with a carbonylation catalyst in the presence of a carbonylation solvent in the first reaction zone to convert at least a portion of the EO to a beta propiolactone (BPL) product stream, wherein the BPL product stream comprises BPL, carbonylation catalyst, and carbonylation solvent, and wherein the reaction of converting at least a portion of the EO to a beta propiolactone (BPL) product stream is a continuous reaction; separating at least a portion of carbonylation catalyst from the BPL product stream to produce a carbonylation catalyst recycling stream and a processed BPL product stream, wherein the processed BPL product stream comprises BPL and carbonylation solvent; directing the processed BPL product stream to a carbonylation solvent removal zone; removing at least a portion of the carbonylation solvent from the processed BPL product stream to produce a polymerization feed stream, wherein the polymerization feed stream comprises BPL; directing the polymerization feed stream to a second reaction zone; contacting BPL in the polymerization feed stream with a polymerization catalyst in the second reaction zone to produce PPL; and further comprising introducing a polymerization solvent into the polymerization feed stream, prior to contacting the polymerization feed stream with the polymerization catalyst, wherein the polymerization solvent is different from the carbonylation solvent, and wherein the conversion of BPL to PPL is performed in a continuous flow format. <EOS>