Kimberly-clark Worldwide, Inc.

Tom Eby

Vasily Aramovich Topolkaraev

Ryan J McEneany

Neil T Scholl

Peiguang Zhou

Gregory James Wideman

Tyler J Lark

Polylactic acid fibers formed from a thermoplastic composition that contains polylactic acid and a polymeric toughening additive are provided. The present inventors have discovered that the specific nature of the components and process by which they are blended may be carefully controlled to achieve a composition having desirable morphological features. More particularly, the toughening additive can be dispersed as discrete physical domains within a continuous phase of the polylactic acid. These domains have a particular size, shape, and distribution such that upon fiber drawing, they absorb energy and become elongated. This allows the resulting composition to exhibit a more pliable and softer behavior than the otherwise rigid polylactic acid. Through selective control over the components and method employed, the present inventors have discovered that the resulting fibers may thus exhibit good mechanical properties, both during and after melt spinning.

Toughened polylactic acid fibers

An oil absorbing material is generally provided. The oil absorbing material can includes sorbent particles having an average aspect ratio of about 5 to about 500 and a mean average particle diameter of about 10 &#x3bc;m to about 1 millimeter. The oil absorbing material comprises polypropylene, polyethylene, inorganic filler particles, and absorbent core material. In one embodiment, the sorbent particles can have an average specific surface area of about 0.25 to about 5.0 m/g and can have a bulk density that is about 0.01 g/cmto about 0.8 g/cm. Processes of making the oil absorbing material are also provided via a solid-state shear pulverization recycling process transforming absorbent article waste into the oil absorbing material. The process can include pulverizing the absorbent article waste to form sorbent particles while cooling the absorbent article waste in an amount sufficient to maintain the absorbent article waste in a solid state.

Oil absorbing material and processes of recycling absorbent articles to produce the same

A method for forming biodegradable fibers is provided. The method includes blending polylactic acid with a polyepoxide modifier to form a thermoplastic composition, extruding the thermoplastic composition through a die, and thereafter passing the extruded composition through a die to form a fiber. Without intending to be limited by theory, it is believed that the polyepoxide modifier reacts with the polylactic acid and results in branching of its polymer backbone, thereby improving its melt strength and stability during fiber spinning without significantly reducing glass transition temperature. The reaction-induced branching can also increase molecular weight, which may lead to improved fiber ductility and the ability to better dissipate energy when subjected to an elongation force. To minimize premature reaction, the polylactic acid and polyepoxide modifier are first blended together at a relatively low temperature(s). Nevertheless, a relatively high shear rate may be employed during blending to induce chain scission of the polylactic acid backbone, thereby making more hydroxyl and/or carboxyl groups available for subsequent reaction with the polyepoxide modifier. Once blended, the temperature(s) employed during extrusion of the blended composition can be selected to both melt the composition and initiate a reaction of the polyepoxide modifier with hydroxyl and/or carboxyl groups of the polylactic acid. Through selective control over this method, the present inventors have discovered that the resulting fibers may exhibit good mechanical properties, both during and after melt spinning.

Growing community of inventors

Greenville, WI, United States of America

Tom Eby