Multicomponent fibers capable of thermally induced shape recovery and the making thereof

Abstract

Multicomponent fibers and films, which can be deformed at room temperature and exhibit thermally-actuated shape recovery properties and methods of their use are provided.

1 . A multicomponent fiber or film comprising at least one component capable of forming a physically-crosslinked network and at least a second component capable of transitioning in response to a thermal stimulus, wherein the two components have strong interfacial adhesion; and wherein a temperature associated with the second component capable of transitioning in response to a thermal stimulus is lower than a temperature required to disrupt the molecular network of the component capable of forming a physically-crosslinked network. 
     
     
         2 . The fiber or film of  claim 1 , wherein the fiber or film comprises at least two co-spun or co-extruded components configured in a core component-sheath component cross-sectional geometry, wherein the core component comprises a thermoplastic elastomer capable of forming a physically-crosslinked network and the sheath component comprises a polyolefin capable of transitioning in response to a thermal stimulus, and wherein the fiber can be deformed from an original shape, retain a temporary shape and subsequently return to its original shape in response to a thermal stimulus. 
     
     
         3 . The fiber or film of  claim 2 , wherein the core component comprises a thermoplastic elastomer. 
     
     
         4 . The fiber or film of  claim 3 , wherein the thermoplastic elastomer comprises a styrenic block copolymer. 
     
     
         5 . The fiber or film of  claim 4  wherein the styrenic block copolymer is selected from the group consisting of poly(styrene-b-butadiene-b-styrene) (SBS), poly(styrene-b-isoprene-b-styrene) (SIS), poly[styrene-b-(ethylene-co-propylene)-b-styrene] (SEPS), and poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS). 
     
     
         6 . The fiber or film of  claim 1 , wherein the sheath component comprises a linear low density polyethylene (LLDPE). 
     
     
         7 . The fiber or film of  claim 1 , wherein the core component comprises SEBS and the sheath comprises LLDPE. 
     
     
         8 . The fiber or film of  claim 1 , wherein the sheath component and the core component are present in the fiber in a w/w ratio having a range selected from the group consisting of 95/5 (sheath/core), 90/10, 85/15, 80/20, 75/25, 70/30, 65/35, 60/40, 55/45, 50/50, 45/55, 40/60, 35/65, 30/70, 25/75, 20/80, 15/85, 10/90, and 5/95. 
     
     
         9 . The fiber or film of  claim 8  wherein the core component and the sheath component have a w/w ratio of about 40/60 (sheath/core), 
     
     
         10 . The fiber or film of  claim 2 , comprising three co-spun or co-extruded components configured in an inner core component-outer core component-sheath component cross-sectional geometry, wherein at least one of the core components comprises a thermoplastic elastomer and the sheath component comprises a polyolefin, and wherein the fiber can be deformed from an original shape and return to the original shape in response to a thermal stimulus. 
     
     
         11 . The fiber or film of  claim 10 , wherein the inner core component/outer core component/sheath component comprise LLDPE/SEBS/LLDPE. 
     
     
         12 . The fiber or film of  claim 2 , wherein the fiber or film returns to the original shape within about 5 sec after being exposed to a thermal stimulus. 
     
     
         13 . The fiber or film of  claim 2 , wherein the fiber or film returns to the original shape within about 2 sec after being exposed to a thermal stimulus. 
     
     
         14 . The fiber or film of  claim 2 , wherein the fiber or film exhibits a repeatable shape recovery. 
     
     
         15 . The fiber or film of  claim 2 , wherein the fiber or film is capable of deforming to at least about four times an original length. 
     
     
         16 . The fiber or film of  claim 2 , wherein the sheath component has a melting point lower than the upper glass transition temperature point of the network-forming core component. 
     
     
         17 . The fiber or film of  claim 16 , wherein the core component has an upper glass transition temperature in the range from about 90° C. to about 140° C. 
     
     
         18 . The fiber or film of  claim 2 , wherein the core component further comprises one or more additives. 
     
     
         19 . The fiber or film of  claim 18 , wherein the additive comprises a long-chain alkyl compound. 
     
     
         20 . The fiber or film of  claim 18 , wherein the core component comprising one or more additives has an upper glass transition temperature higher than the core component not having the additives. 
     
     
         21 . An article comprising a fiber or film of  claim 1 . 
     
     
         22 . The article of  claim 21 , wherein the article comprises a thermal actuator in a deployable device. 
     
     
         23 . The article of  claim 21 , wherein the article is selected from the group consisting of a diaper, a waist band, a stretch panel, a disposable garment, a medical or personal hygiene article, and a filter. 
     
     
         24 . The article of  claim 21 , wherein the article is selected from the group consisting of a hinge, a truss, an antenna, a solar panel, and an optical reflector. 
     
     
         25 . The article of  claim 21 , wherein the article is selected from the group consisting of a form fitting material, self-sealing packaging, a smart textile, and an intelligent fiber. 
     
     
         26 . The article of  claim 21 , wherein the article is selected from the group consisting of a wound closure suture, a vascular stent, a bone-setting sleeve, and a drug delivery device.