An acrylic rubber bale excellent in storage stability and water resistance and a method for producing the same are provided. An acrylic rubber bale, including an acrylic rubber having a reactive group, with a specific ash content, a large proportion of magnesium and phosphorus in the ash, and a specific ratio of magnesium and phosphorus, is highly excellent in storage stability and water resistance. This acrylic rubber bale can be produced by using a specific stabilizer and a specific coagulant in an emulsion polymerization process of an acrylic rubber and performing a process from coagulation process to baling process under specific conditions.

An acrylic rubber sheet excellent in storage stability and water resistance, a method for producing the same, a rubber mixture containing the acrylic rubber sheet and a rubber cross-linked product thereof are provided. The acrylic rubber sheet according to the present invention includes an acrylic rubber having a reactive group and having a weight average molecular weight (Mw), a ratio of a Z-average molecular weight (Mz) and a weight average molecular weight (Mw) in a specific range. The acrylic rubber sheet according to the present invention has an ash content of 0.2% by weight or less, an amount of gel insoluble in methyl ethyl ketone is 50% by weight or less, and a water content of less than 1% by weight, and is excellent in water resistance and highly well-balanced in strength properties and processability.

An acrylic rubber sheet excellent in storage stability and water resistance, a method for producing the same, a rubber mixture containing the acrylic rubber sheet and a rubber cross-linked product thereof are provided. The acrylic rubber sheet according to the present invention includes an acrylic rubber having a reactive group and having a weight average molecular weight (Mw), a ratio of a Z-average molecular weight (Mz) and a weight average molecular weight (Mw) in a specific range. The acrylic rubber sheet according to the present invention has an ash content of 0.2% by weight or less, an amount of gel insoluble in methyl ethyl ketone is 50% by weight or less, and a water content of less than 1% by weight, and is excellent in water resistance and highly well-balanced in strength properties and processability.

Acrylic rubber bale having remarkably improved storage stability and water resistance without deteriorating cross-linking properties, a method of production, a rubber mixture obtained by mixing the acrylic rubber bale, a method of production, and a rubber cross-linked product obtained by cross-linking the same is provided. The acrylic rubber bale includes an acrylic rubber, and the acrylic rubber is mainly composed of (meth) acrylic acid ester, and has a weight average molecular weight of 100,000 to 5,000,000, and has a ratio of a Z-average molecular weight and a weight average molecular weight of 1.3 or more, where an ash content is 0.6% by weight or less, and the ash contains a periodic table group 2 metal and phosphorus, and a phosphorus content is 10% by weight or more, and the ratio of the periodic table group 2 metal to phosphorus is in the range of 0.6 to 2 molar ratio.

Acrylic rubber bale having remarkably improved storage stability and water resistance without deteriorating cross-linking properties, a method of production, a rubber mixture obtained by mixing the acrylic rubber bale, a method of production, and a rubber cross-linked product obtained by cross-linking the same is provided. The acrylic rubber bale includes an acrylic rubber, and the acrylic rubber is mainly composed of (meth) acrylic acid ester, and has a weight average molecular weight of 100,000 to 5,000,000, and has a ratio of a Z-average molecular weight and a weight average molecular weight of 1.3 or more, where an ash content is 0.6% by weight or less, and the ash contains a periodic table group 2 metal and phosphorus, and a phosphorus content is 10% by weight or more, and the ratio of the periodic table group 2 metal to phosphorus is in the range of 0.6 to 2 molar ratio.

The present disclosure relates to a preparation method of a super absorbent polymer capable of improving absorption performance of the super absorbent polymer by adding a simple additive later. The preparation method includes the steps of: forming a hydrogel polymer by cross-linking and polymerizing a water-soluble ethylene-based unsaturated monomer having at least partially neutralized acidic groups in the presence of an internal cross-linking agent; drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; forming a surface cross-linked layer by further cross-linking a surface of the base resin powder in the presence of a surface cross-linking agent, adding a monovalent to trivalent metal cation on the surface cross-linked base resin powder at a temperature of 25° C. to 80° C., and maintaining and aging the resulting metal cation-added product at a temperature of 40° C. to 60° C. for 10 to 30 minutes.

The present disclosure relates to a preparation method of a super absorbent polymer capable of improving absorption performance of the super absorbent polymer by adding a simple additive later. The preparation method includes the steps of: forming a hydrogel polymer by cross-linking and polymerizing a water-soluble ethylene-based unsaturated monomer having at least partially neutralized acidic groups in the presence of an internal cross-linking agent; drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; forming a surface cross-linked layer by further cross-linking a surface of the base resin powder in the presence of a surface cross-linking agent, adding a monovalent to trivalent metal cation on the surface cross-linked base resin powder at a temperature of 25° C. to 80° C., and maintaining and aging the resulting metal cation-added product at a temperature of 40° C. to 60° C. for 10 to 30 minutes.

According to one or more embodiments disclosed herein, the amount of one or more contaminants in an initial ultra high molecular weight polyethylene composition may be reduced by a method including contacting the initial ultra high molecular weight polyethylene composition with an acid to form a processed ultra high molecular weight polyethylene composition. The initial ultra high molecular weight polyethylene composition may include at least 0.02 wt. % of one or more contaminants. The contacting of the acid with the initial ultra high molecular weight polyethylene composition may be for a time, at a pressure, and at a temperature sufficient to reduce the amount of the one or more contaminants in the initial ultra high molecular weight polyethylene.

According to one or more embodiments disclosed herein, the amount of one or more contaminants in an initial ultra high molecular weight polyethylene composition may be reduced by a method including contacting the initial ultra high molecular weight polyethylene composition with an acid to form a processed ultra high molecular weight polyethylene composition. The initial ultra high molecular weight polyethylene composition may include at least 0.02 wt. % of one or more contaminants. The contacting of the acid with the initial ultra high molecular weight polyethylene composition may be for a time, at a pressure, and at a temperature sufficient to reduce the amount of the one or more contaminants in the initial ultra high molecular weight polyethylene.

A process for producing superabsorbent particles by polymerizing a monomer solution or suspension, comprising drying of the resultant aqueous polymer gel in an air circulation belt dryer, grinding, classifying, and optionally thermal surface postcrosslinking, wherein the aqueous polymer gel is introduced into the air circulation belt dryer by means of an oscillating conveyor belt and that guide devices are located at the edges of the conveyor belt.