Provided are: a thermal stabilizer composition which does not generate an odor of a phosphorus-based antioxidant; and a synthetic resin composition comprising the same. The thermal stabilizer composition comprises: 100 parts by mass of a phosphorus-based antioxidant having a phosphite structure; and 0.001 to 10 parts by mass of a phenolic antioxidant having a substructure represented by the following Formula (1):

##STR00001## (wherein, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms; a represents an integer of 0 to 2; and, when a is 2, plural R.sup.3s are optionally the same or different).

Provided are: a thermal stabilizer composition which does not generate an odor of a phosphorus-based antioxidant; and a synthetic resin composition comprising the same. The thermal stabilizer composition comprises: 100 parts by mass of a phosphorus-based antioxidant having a phosphite structure; and 0.001 to 10 parts by mass of a phenolic antioxidant having a substructure represented by the following Formula (1):

##STR00001## (wherein, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms; a represents an integer of 0 to 2; and, when a is 2, plural R.sup.3s are optionally the same or different).

Described are compositions and methods for inhibiting polymerization of a monomer (e.g., styrene) composition a quinone methide polymerization retarder and an ammonium salt. In a mixture, the ammonium salt improves the efficacy of the quinone methide polymerization retarder and provides greater antipolymerant activity. In turn, the mixture reduces or prevents apparatus fouling and improves the purity of monomer streams.

Described are compositions and methods for inhibiting polymerization of a monomer (e.g., styrene) composition a quinone methide polymerization retarder and an ammonium salt. In a mixture, the ammonium salt improves the efficacy of the quinone methide polymerization retarder and provides greater antipolymerant activity. In turn, the mixture reduces or prevents apparatus fouling and improves the purity of monomer streams.

A method of producing a non-petroleum based electrical insulating oil, wherein the method can include providing a primary mixture of non-petroleum origin, containing isomerized straight chain hydrocarbons; performing a distillation and/or stripping of the primary mixture; collecting a paraffinic base oil as a product of the distillation and/or stripping, containing a mixture of isoalkanes and alkanes; and mixing the base oil with an antioxidant additive.

A method of producing a non-petroleum based electrical insulating oil, wherein the method can include providing a primary mixture of non-petroleum origin, containing isomerized straight chain hydrocarbons; performing a distillation and/or stripping of the primary mixture; collecting a paraffinic base oil as a product of the distillation and/or stripping, containing a mixture of isoalkanes and alkanes; and mixing the base oil with an antioxidant additive.

Methods for preparing alkenylphenone corrosion inhibiting compositions may include providing an arylacetone and reacting the arylacetone with formaldehyde in the presence of a strong base catalyst. Corrosion inhibiting compositions may include an alkenylphenone, which may be prepared by a method including providing an arylacetone and reacting the arylacetone with formaldehyde in the presence of a strong base catalyst. Methods of inhibiting corrosion of a steel surface of an oilfield equipment component may include contacting the steel surface with an aqueous solution comprising a corrosion inhibitor. The corrosion inhibitor may include a composition containing an alkenylphenone prepared by reacting an arylacetone with formaldehyde in the presence of a strong base catalyst.

Methods for preparing alkenylphenone corrosion inhibiting compositions may include providing an arylacetone and reacting the arylacetone with formaldehyde in the presence of a strong base catalyst. Corrosion inhibiting compositions may include an alkenylphenone, which may be prepared by a method including providing an arylacetone and reacting the arylacetone with formaldehyde in the presence of a strong base catalyst. Methods of inhibiting corrosion of a steel surface of an oilfield equipment component may include contacting the steel surface with an aqueous solution comprising a corrosion inhibitor. The corrosion inhibitor may include a composition containing an alkenylphenone prepared by reacting an arylacetone with formaldehyde in the presence of a strong base catalyst.

Methacrolein is prepared in a continuous process by a Mannich condensation reaction of formaldehyde with propanal. A methacrolein polymerization inhibitor is introduced during the production process and a part thereof is recycled back into the reactor where the Mannich condensation reaction is carried out.

Methacrolein is prepared in a continuous process by a Mannich condensation reaction of formaldehyde with propanal. A methacrolein polymerization inhibitor is introduced during the production process and a part thereof is recycled back into the reactor where the Mannich condensation reaction is carried out.