Kimberly-clark Corporation

Jose F Pazos

Sharon L Greene

Augusto Rodriguez

Fidelis C Onwumere

Chad E Garvey

Michael Tod Morman

Gerard J Ring

Michael T Mormon

The invention provides a polymer adapted for use in melt processes, the polymer having a thermally reversible bond which is adapted to evanesce at an elevated temperature and revert to a thermally reversible bond upon cooling to ambient temperature so that the polymer is adapted, upon being heated to the elevated temperature, to dissociate into melt processable polymeric fragments and, upon being cooled to ambient temperature, to re-associate. The thermally reversible bond is a bond that is capable of evanescing at a temperature which is lower than the degradation temperature of the polymer fragments. The thermally reversible bond may be, for example, a thermally reversible aromatic urethane bond.

Thermally reversible polymers

The invention provides fibers and sheets formed from a polymer having a thermally reversible bond which is adapted to evanesce at an elevated temperature and revert to a thermally reversible bond upon cooling to ambient temperature so that said polymer is adapted, upon being heated to said elevated temperature, to dissociate into melt processable polymer fragments and, upon being cooled from said elevated temperature to ambient temperature, to re-associate. The polymer fibers may be meltblown fibers which may be formed into a coherent nonwoven web or sheet. The meltblown fibers may include microfibers. The meltblown web may also include at least one type of secondary fiber, particulates or a mixture of fibers and particulates.

Thermally reversible polymer sheets and method of forming the same

A superabsorbent, thermoplastic polymeric composition comprising:

Superabsorbent thermoplastic compositions and nonwoven webs prepared

A nonwoven superabsorbent web comprising fibers composed of a superabsorbent, thermoplastic polymeric composition, such as a nonwoven superabsorbent web comprising a plurality of substantially randomly deposited monofilaments of a thermoplastic superabsorbent. Such a web is prepared by meltblowing a thermoplastic superabsorbent.

Meltblown superabsorbent thermoplastic compositions

A superabsorbent polyurethane foam which contains a plurality of polycarbonyl moieties covalently attached to the polyurethane through at least one urethane, thiourethane, or urea linkage. The carbonyl portions of such polycarbonyl moieties can be carbamoyl, substituted carbamoyl, or carboxy or the alkali metal or ammonium salts thereof. The foam can be prepared by mixing an isocyanate-terminated prepolymer with a first compound having at least one isocyanate-reactive group and at least one carbon-carbon double bond, allowing the mixture to react, and then mixing with the resulting product an aqueous solution of a carboxylate-containing second compound having at least one carbon-carbon double bond. A thermally activated free radical initiator is present in the final reaction mixture. Preferably, the polyurethane is derived from an isocyanate-terminated poly(oxyalkylene) polyol having an isocyanate functionality greater than two and the polycarbonyl moieties are derived from second compounds which typically are acrylate or methacrylate salts, i.e., alkali metal or ammonium salts of acrylic or methacrylic acid. The first compound usually is the 2-hydroxyethyl ester of acrylic or methacrylic acid. Such superabsorbent polyurethane foam is useful in the manufacture of absorbent articles, especially disposable absorbent articles such as diapers, sanitary napkins, bedpads, incontinent pads, and the like.

Process of making a crosslinked superabsorbent polyurethane foam

A superabsorbent polyurethane foam based on an interpenetrating polymer network of a crosslinked polyurethane and a crosslinked addition polymer containing a plurality of chain segments made up of functional group-containing repeating units which may be the same or different. The functional groups of the repeating units are selected from the group consisting of carbamoyl, substituted carbamoyl, and carboxy and the alkali metal and ammonium salts thereof. A method of preparing the foams is described which involves forming the polyurethane foam in the presence of addition polymerizable monomers and crosslinking agent and a thermally activated free radical initiator. Addition polymerization can take place during or after foam formation. Reactants and reaction conditions are selected so as to essentially avoid grafting addition polymer to polyurethane. Preferably, the polyurethane is derived from an isocyanate-terminated poly(oxyalkylene) polyol having an isocyanate functionality greater than two and the addition polymer is the reaction product of a crosslinking agent, such as methylene-bis-acrylamide and 1,6-hexanediol diacrylate, with at least one compound selected from the group consisting of acrylamides, substituted acrylamides, and acrylate and methacrylate salts, i.e., alkali metal and ammonium salts of acrylic and methacrylic acid. Such superabsorbent polyurethane foam is useful in the manufacture of absorbent articles, especially disposable absorbent articles such as diapers, sanitary napkins, bedpads, incontinent pads, and the like.

Growing community of inventors

Roswell, GA, United States of America

Jose F Pazos