Polymerization inhibitor compositions are provided. The polymerization inhibitor compositions may include at least one hydroxylamine of a nitroxide and at least one phenylenediamine. Methods of inhibiting the unwanted polymerization of monomers are also provided. The methods include adding the presently disclosed polymerization inhibitor compositions to a fluid containing the monomers. The monomers may be ethylenically unsaturated monomers, such as acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrolein, methacrolein, acrylate, methacrylate, acrylamide, methacrylamide, vinyl acetate, butadiene, ethylene, propylene, and styrene.

A method for preparing diphenol compounds includes adding a hydroxyphenyl carboxylic acid, a tyrosine ethyl ester, hydroxybenzotriazole hydrate and a solvent and stirring to produce a first solution. EDCl HCl is added to the first solution to produce a first mixture. Ethyl acetate is added to the first mixture to produce a second mixture. The second mixture is added to sodium chloride to produce a third mixture having layer separation. An aqueous layer is removed from the third mixture. The third mixture is extracted with reagents after the aqueous layer has been removed from the third mixture to produce a fourth mixture. Magnesium sulfate is added to the fourth mixture to produce a fifth mixture. The fifth mixture is filtered to produce filtrate. The filtrate is concentrated. Crystallization of the concentrated filtrate is induced. Methylene chloride is added to the crystallized filtrate to produce a solid product.

A method for preparing diphenol compounds includes adding a hydroxyphenyl carboxylic acid, a tyrosine ethyl ester, hydroxybenzotriazole hydrate and a solvent and stirring to produce a first solution. EDCl HCl is added to the first solution to produce a first mixture. Ethyl acetate is added to the first mixture to produce a second mixture. The second mixture is added to sodium chloride to produce a third mixture having layer separation. An aqueous layer is removed from the third mixture. The third mixture is extracted with reagents after the aqueous layer has been removed from the third mixture to produce a fourth mixture. Magnesium sulfate is added to the fourth mixture to produce a fifth mixture. The fifth mixture is filtered to produce filtrate. The filtrate is concentrated. Crystallization of the concentrated filtrate is induced. Methylene chloride is added to the crystallized filtrate to produce a solid product.

A method for preparing diphenol compounds includes adding a hydroxyphenyl carboxylic acid, a tyrosine ethyl ester, hydroxybenzotriazole hydrate and a solvent and stirring to produce a first solution. EDCl HCl is added to the first solution to produce a first mixture. Ethyl acetate is added to the first mixture to produce a second mixture. The second mixture is added to sodium chloride to produce a third mixture having layer separation. An aqueous layer is removed from the third mixture. The third mixture is extracted with reagents after the aqueous layer has been removed from the third mixture to produce a fourth mixture. Magnesium sulfate is added to the fourth mixture to produce a fifth mixture. The fifth mixture is filtered to produce filtrate. The filtrate is concentrated. Crystallization of the concentrated filtrate is induced. Methylene chloride is added to the crystallized filtrate to produce a solid product.

Polymerization inhibitor compositions are provided. The polymerization inhibitor compositions may include at least one hydroxylamine of a nitroxide and at least one phenylenediamine. Methods of inhibiting the unwanted polymerization of monomers are also provided. The methods include adding the presently disclosed polymerization inhibitor compositions to a fluid containing the monomers. The monomers may be ethylenically unsaturated monomers, such as acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrolein, methacrolein, acrylate, methacrylate, acrylamide, methacrylamide, vinyl acetate, butadiene, ethylene, propylene, and styrene.

Polymerization inhibitor compositions are provided. The polymerization inhibitor compositions may include at least one hydroxylamine of a nitroxide and at least one phenylenediamine. Methods of inhibiting the unwanted polymerization of monomers are also provided. The methods include adding the presently disclosed polymerization inhibitor compositions to a fluid containing the monomers. The monomers may be ethylenically unsaturated monomers, such as acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrolein, methacrolein, acrylate, methacrylate, acrylamide, methacrylamide, vinyl acetate, butadiene, ethylene, propylene, and styrene.

Polymerization inhibitor compositions are provided. The polymerization inhibitor compositions may include at least one hydroxylamine of a nitroxide and at least one phenylenediamine. Methods of inhibiting the unwanted polymerization of monomers are also provided. The methods include adding the presently disclosed polymerization inhibitor compositions to a fluid containing the monomers. The monomers may be ethylenically unsaturated monomers, such as acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, acrolein, methacrolein, acrylate, methacrylate, acrylamide, methacrylamide, vinyl acetate, butadiene, ethylene, propylene, and styrene.

Disclosed herein are compositions including between 20 wt % and 50 wt % of a nitroxyl compound such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl. The compositions are stable under field conditions of transportation and storage. The compositions remain homogeneous and pumpable or pourable at temperatures between 20 C. and 60 C., even when temperatures fluctuate in this range over a period of 10 days to 5 years, and even where the container used to transport and store the composition is made from metal or includes a metal surface contacting the composition.

Disclosed herein are compositions including between 20 wt % and 50 wt % of a nitroxyl compound such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl. The compositions are stable under field conditions of transportation and storage. The compositions remain homogeneous and pumpable or pourable at temperatures between 20 C. and 60 C., even when temperatures fluctuate in this range over a period of 10 days to 5 years, and even where the container used to transport and store the composition is made from metal or includes a metal surface contacting the composition.

Aspects of the disclosure includes methods for preparing an amorphous solid composition of a fatty acid metal salt. In practicing the subject methods according to certain embodiments, a succinylated 3-(fatty acid amido)-2-hydroxy-1-(protected hydroxy)-propane organic salt is contacted with a metal base to produce a succinylated 3-(fatty acid amido)-2-hydroxy-1-(protected hydroxy)-propane metal salt; and the succinylated 3-(fatty acid amido)-2-hydroxy-1-(protected hydroxy)-propane metal salt is precipitated in a solvent to produce an amorphous solid succinylated 3-(fatty acid amido)-2-hydroxy-1-(protected hydroxy)-propane metal salt composition. An amorphous solid succinylated 3-(fatty acid amido)-2-hydroxy-1-(protected hydroxy)-propane lithium salt is also provided.