US-20260125511-A1 - POLYMERIZATION OF LACTONES IN POLAR PROTIC SOLVENTS

US20260125511A1US 20260125511 A1US20260125511 A1US 20260125511A1US-20260125511-A1

Abstract

A method includes contacting one or more beta-propiolactone monomers and one or more phosphorous compound in a solution under conditions such that a polypropiolactone polymer is formed. The solution comprises one or more polar protic solvents and the one or more phosphorous compounds. The phosphorous compound comprises phosphorous in an ionic form that is either covalently bound to another compound to form a zwitterion or ionically bound to another compound to form a salt.

Inventors

Christopher A. DeRosa
Catherine A. Falkner

Assignees

NOVOMER, INC.

Dates

Publication Date: 20260507
Application Date: 20240125

Claims (20)

1 . A method, comprising: a) contacting one or more beta-propiolactone monomers and one or more phosphorous compounds and optionally one or more carboxylate compounds in a solution under conditions such that a polypropiolactone polymer is formed, wherein the solution comprises one or more polar protic solvents and the one or more phosphorous compounds and optionally the one or more carboxylate compounds, and wherein the phosphorous compound comprises phosphorous in an ionic form that is either covalently bound to another compound to form a zwitterion or ionically bound to another compound to form a salt.
2 . The method of claim 1 , wherein the phosphorous compound comprises a phosphonium compound or an anionic phosphate compound.
3 . The method of claim 1 , wherein the phosphorous compound comprises one of more of formulas I, II, and/or III: wherein each R 3 is separately in each occurrence a hydrocarbyl group wherein two or more of R 3 may form one or more aromatic or non-aromatic ring structures which may optionally contain one or more heteroatoms. wherein R a comprises a phosphate group, a carboxylate group, a carbonate group, an alkoxide group, a halide, or any combination thereof; or wherein R 5 is independently a quaternary ammonium group, a phosphonium group, another omnium cation, or any combination thereof; and wherein R 2 is defined herein; or wherein each R 2 is defined herein; and wherein solid lines represent covalent bonds and dotted lines represent ionic bonds; wherein R b comprises a quaternary ammonium group, a phosphonium group, another onium cation, or any combination thereof.
4 . The method of claim 1 , wherein the phosphorous compound comprises a cationic phosphine compound and an anionic carboxylate having an anionic carboxylate compound having a C 5-20 alkyl group.
5 . The method of claim 1 , wherein the phosphorous compound comprises an anionic phosphate and a cationic quaternary ammonium compound.
6 . The method of claim 1 , wherein the phosphorous compound comprises one or more C 5-20 alkyl groups covalently bound to a group that is anionic or cationic.
7 . The method of claim 1 , wherein the phosphorous compound comprises a cation and an anion that are covalently bonded to each other.
8 . The method of claim 1 , wherein the phosphorous compound comprises a cation and an anion that are ionically bound to each other.
9 . The method of claim 1 , wherein the one or more carboxylate compounds comprises a carboxylate compound and a counterion that are dissolvable in the polar protic solvent.
10 . The method of claim 1 , wherein the one or more carboxylate compounds comprise a formula according to a following compound: wherein R 2 and R b are defined herein and dotted line is defined herein.
11 . The method of claim 1 , wherein the one or more polar protic solvents are present in a mass percent that is greater than about 90 percent, based on a total mass of the solution when beta-lactone monomer and the solution are contacted.
12 . The method of claim 1 , wherein the one or more polar protic solvents comprise one or more of water, methanol, ethanol, acetic acid, isopropanol, n-butanol, formic acid, or any combination thereof.
13 . The method of claim 1 , wherein the one or more polar protic solvents comprise water.
14 . The method of claim 1 , wherein beta-lactone monomer is present in the solution at a mass percent of about 5 percent to about 35 percent based on total mass of the solution when the beta-propiolactone monomer and the solution are contacted.
15 . (canceled)
16 . (canceled)
17 . (canceled)
18 . (canceled)
19 . The method of claim 1 , wherein essentially all of beta-lactone monomer is converted to the polypropiolactone polymer or a side product in about 3 hours or less.
20 . (canceled)

Description

FIELD The present disclosure relates to a method for making polypropiolactone using polar protic solvents. BACKGROUND Beta-lactone monomers are useful to form polypropiolactone polymers. The polypropiolactone polymers are biodegradable and, because of this, have many uses for food and/or beverage packaging. Normally, polypropiolactone polymers are formed by contacting beta-lactone monomers and an initiator in the presence of an aprotic solvent. See, for example, U.S. Pat. No. 11,492,443. However, these solvents can be expensive and undesirable to the environment when disposed of, and the polypropiolactone polymers produced by these techniques can contain side-product or unreacted chemicals that are undesirable in food and/or beverage packaging. Accordingly, what is needed are techniques to make polypropiolactone free of chemicals considered hazardous to humans. What is needed are techniques to produce polypropiolactone polymers with minimal solvent waste. What is needed are techniques to produce polypropiolactone polymers that can be applied as films and/or coatings. SUMMARY Disclosed herein are methods of forming a polypropiolactone using a polar protic solvent. Disclosed is a method including contacting one or more beta-propiolactone monomers and one or more phosphorous compounds and optionally one or more carboxylate compounds in a solution under conditions such that a polypropiolactone polymer is formed. The solution includes one or more polar protic solvents and the one or more phosphorous and optionally the one or more carboxylate compounds. The phosphorous compound includes phosphorous in an ionic form that is either covalently bound to another compound to form a zwitterion or ionically bound to another compound to form a salt. The phosphorous compound may include a phosphonium compound or an anionic phosphate compound. The phosphorous compound may include a compound having the following structure according to formulas I, II, and/or III: wherein each R3 is separately in each occurrence a group containing one or more carbon atoms wherein two or more of R3 may form one or more aromatic or non-aromatic ring structures which may optionally contain one or more heteroatoms,wherein the solid lines represent covalent bonds and the dotted lines represent ionic bonds.wherein Ra comprises a phosphate group, a carboxylate group, a carbonate group, an alkoxide group, a halide, or any combination thereof; or wherein R5 is independently a quaternary ammonium group, a phosphonium group, another omnium cation, or any combination thereof; andwherein R2 is defined herein; or wherein each R2 is defined herein; andwherein Rb comprises a quaternary ammonium group, a phosphonium group, another onium cation, or any combination thereof. The phosphorous compound may include the cationic phosphine compound and an anionic carboxylate having an anionic carboxylate compound having a C5-20 alkyl group. The phosphorous compound may include an anionic phosphate and a cationic quaternary ammonium compound. The phosphorous compound may include one or more C5-20 alkyl groups covalently bound to a group that is anionic or cationic. The phosphorous compound may include a cation and an anion that are covalently bonded to each other. The phosphorous compound may include a cation and an anion that are ionically bound to each other. The one or more carboxylate compounds may include a carboxylate compound and a counterion that are dissolvable or dispersible in the polar protic solvent. The one or more carboxylate compounds may comprise a formula according to the following: wherein R2 and Rb are defined herein and the dotted line is defined herein. The one or more polar protic solvents may be present in a mass percent that is greater than about 90 percent, based on the total mass of the solution when the beta-lactone monomer and the solution are contacted. The one or more polar protic solvents may comprise one or more of water, methanol, ethanol, acetic acid, isopropanol, n-butanol, formic acid, or any combination thereof. The one or more polar protic solvents may comprise water. The beta-lactone monomer may be present in the solution at a mass percent of about 5 percent to about 35 percent based on the total mass of the solution when the beta-lactone monomer and the solution are contacted. The beta-lactone monomer may be present in the solution at a mass percent of about 5 percent to about 25 percent based on the total mass of the solution when the beta-lactone monomer and the solution are contacted. The beta-lactone monomer may be present in the solution at a mass percent of about 5 percent to about 20 percent based on the total mass of the solution when the beta-lactone monomer and the solution are contacted. The method may further include contacting the one or more phosphorous compounds and the one or more polar protic solvents to form the solution, before the beta-lactone monomer is contacted with the solution. The method may further incl