The present invention relates to a superabsorbent polymer exhibiting excellent heat stability.

The present invention relates to a superabsorbent polymer exhibiting excellent heat stability.

A coextruded biaxially oriented composite film comprising a polyester substrate layer and disposed on one or both surfaces thereof a strippable sacrificial layer, wherein said strippable sacrificial layer comprises an ethylene-methacrylic acid (EMAA) copolymer.

In some aspects, the disclosure relates to thermoset polymeric compositions consisting of functional bio-based epoxies and/or their derivatives (e.g. epoxidized vegetable oil(s)), along with carboxyl functional acrylics and/or polyesters. When cured, example compositions yield high performance products suitable for composite, coating, adhesive, sealant, and/or elastomer applications. When used in stone composite formulations with suitable fillers like quartz and titanium dioxide, example products have high hardness, very low water absorption, and high mechanical strength along with stain, chemical, and heat resistance. When used in coating formulations, example cured films have excellent adhesion, high gloss, clarity, toughness, low water absorption, solvent and chemical resistance, flexibility, and impact resistance without compromising hardness. Coating formulation properties may also include exterior durability. The composition properties may be selectively modified to hard, soft, tough, or elastomeric by selecting the appropriate stoichiometry and type of functional resin to react with epoxy(ies)/derivative(s).

A method of preparing a superabsorbent polymer includes preparing a base resin in which an acrylic acid-based monomer having acidic groups which are at least partially neutralized and an internal crosslinking agent are crosslinked in the presence of a sodium polycarboxylate surfactant; and heating the base resin in the presence of a surface crosslinking agent to carry out surface modification of the base resin, wherein the internal crosslinking agent includes a first epoxy crosslinking agent having an epoxy equivalent weight of 100 g/eq or more to less than 130 g/eq, and a second epoxy crosslinking agent having an epoxy equivalent weight of 130 g/eq or more. The superabsorbent polymer provides improved rewetting property and liquid permeability.

A method of preparing a superabsorbent polymer includes preparing a base resin in which an acrylic acid-based monomer having acidic groups which are at least partially neutralized and an internal crosslinking agent are crosslinked in the presence of a sodium polycarboxylate surfactant; and heating the base resin in the presence of a surface crosslinking agent to carry out surface modification of the base resin, wherein the internal crosslinking agent includes a first epoxy crosslinking agent having an epoxy equivalent weight of 100 g/eq or more to less than 130 g/eq, and a second epoxy crosslinking agent having an epoxy equivalent weight of 130 g/eq or more. The superabsorbent polymer provides improved rewetting property and liquid permeability.

The present invention relates to the synthesis of an associative acrylic (co)polymer by aqueous emulsion radical polymerization. The (co)polymer contains at least one oligomer of acrylic acid represented by the formula (I):

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where n is an integer ranging from 1 to 10. The oligomer is prepared from acrylic acid at a temperature of between 50 C. and 200 C. in the presence of a basic or acid catalyst, water, and polymerization inhibitors. The present invention also relates to the associative acrylic (co)polymer obtained from the method and also to the use of this (co)polymer as a thickener in various formulations.

A coextruded biaxially oriented composite film comprising a polyester substrate layer and disposed on one or both surfaces thereof a strippable sacrificial layer, wherein said strippable sacrificial layer comprises an ethylene-methacrylic acid (EMAA) copolymer.

A coextruded biaxially oriented composite film comprising a polyester substrate layer and disposed on one or both surfaces thereof a strippable sacrificial layer, wherein said strippable sacrificial layer comprises an ethylene-methacrylic acid (EMAA) copolymer.

The present invention provides polyacrylic acid (salt)-based water-absorbing resin powder having an excellent fluid retention capacity under pressure, an excellent water absorption speed, and an excellent liquid permeability and a method for producing the polyacrylic acid (salt)-based water-absorbing resin powder. The earlier-described objects are attained by: a method for producing water-absorbing resin powder which includes adding an inorganic compound to a crosslinked hydrogel polymer obtained in a polymerization step of polymerizing a polyacrylic acid (salt) and performing crushing in specific gel-crushing conditions; and the resultant water-absorbing resin powder.