CA2190255A1 - Conforming shoe construction using gels and method of making the same - Google Patents

Abstract

A shoe that conforms to foot contours and provides cushioning is comprised of a shoe sole and a shoe upper attached to the shoe sole. The shoe upper is comprised of an outer layer, an inner layer and a conforming layer therebetween, wherein a first portion of the conforming layer is comprised of viscoelastic gel and a second portion of the conforming layer is comprised of environmentally-responsive gel. The environmentally-responsive gel is preferably a temperature-responsive gel that will react to the heat emanating from a foot inserted into the shoe to express a liquid. The viscoelastic gel is preferably a soft, flowable gel that conforms to foot contours. The shoe may alternatively incorporate a thermally responsive polymer gel or a reversibly gelling polymer network which exhibits a dramatic change in viscosity in response to a change in environmental stimulus, such as temperature. The thermally responsive polymer gel will react to the heat generated by a foot inserted into the shoe to increase viscosity and provide the foot a measure of support.

Description

WO 96/28057 PCT/~JS96/03480

2 ~ ~û25~, CONFORMING SHOE CONSTRUCTION USING GELS
AND METHOD OF MAKING THE SAME
l~echni~ ~ Fi~ld This invention relates to a ~ 1 fitting shoe ~-7u7LluuL;oll using gels and a method of forming the same. More pdlL;~ul~ly, the invention relates to a shoe that incorporates various gels to provide a . . " . ~ medium for a 1 fitting shoe upper, tongue and foot bed and to methods of forming the shoe upper, tongue and foot bed.

.u..,.~'~ of the Invention Various methods and devices have been employed in shoes to add cushioning to the shoe and to provide eulll~ lLur custom fitting ~ullL~ul~;ulls to the contours of a foot inserted into the shoe. For example, U.S. Patent No. 5,313,717, which issued to the present inventor, is directed to a shoe which incorporates reactive-energy, fluid-filled cavities in the shoe mid-sole. As discussed therein, typical prior art devices provide r7.c~ni~7nin~ and custom fit to the foot inside the shoe by constructing the shoe sole from a sûfter, more resilient material or ;U~ul~JC7l.1L;llg fluid filled pads or bladders in the shoe.
The use of gels to provide a cullru~ 7 fit or cushion is known in the prior art. However, the prior art gels generally set to fit the contours of a foot and do not provide a soft cushion fit or they are soft liquid gels that must be placed in a bladder.
In other shoes designed to provide ~'17~7ir7nin~ or custom fitting, either an air filled foam or an air "pump" has been used to conform to the foot which is inserted into the shoe. The foam is a material that reacts to foot pressure by allowing the air therein to become L.UIII,U~C77C:d and/or escape and therefore resiliently compress upon pressure from the foot. The materials does not have the capability to expand to the non-pressure areas of the foot. Shoes that ;ll~7lluuldLe an air "pump" fill in air around the foot so that the shoe conforms to the foot - therein, but in doing so, increases the pressure on the foot. This increased pressure and foot 7UllUUlld;llg air pocket tends to greatly increase the foot ttlll~ Lulc.
Thus, these solutions provide fit or comfort either by merely displacing at locations WO 96/280s7 2 ~ 9 0 2 5 5 PCTNSg6/03480 of higher pressure or by increasing the pressure completely around the foot. Thus, these shoes do not conform fully to the foot therein at normal pressures.
Sllmn~ry of the Invention The present invention is directed to a shoe which conforms to contours of a foot inserted into the shoe. The shoe employs a solid foam matrix that contains elements of a soft, highly flowable v;,~u.l~;~ gel, a foam and/or an ..lvilvlllll~.lLdlly-responsive gel. Preferably, the shoe uses soft elastomeric gel ûr foamed ~.I~LVI~ ;C gel to provide a flowable, V;~. VCId~ medium that will conform 10 the foot as the foot is inserted into the shoe. The invention is also directed to the use of a temperature-responsive gel that can react to the heat exerted by the foot inserted into the shoe to provide a rnnfnrmin~ medium for fit and . ~l,;....;.~g.
Each of these gels can be located in proper pûsition by ~UIIUUIId;llg the gels with a memory foam or other ~ùllllll~;ally available foams.
In a preferred embodiment of the invention, the shoe il~.Ul~Uld~C~ an cllv;lullll...lLdlly-responsive gel. An cllv;lulllll..l~;~lly-responsive gel is a uu~-u,uoluuS, fast responsive, crosslinked gel obtainable from a polymeric precursor, the gel being of sufficient flexibility to enable the gel to be reversible responsive to a change in an =llv;lu~ l condition. The cllv;lul~ lLdlly-responsive gel can 20 be made *om any responsive polymer with side groups that can react with a di- or multi-functional crosslinking molecule. The polymers can have hydroxyl, acid or amine side groups and which have lower critical solution Ltlll,u..dLulc~ in aqueûus solutions together with water-soluble crosslinkers. Even more particularly, the gel is a ttlll~..dLul~responsive gel and is able to undergo a phase separation which is 25 ~clll~ Lul~induced. Still further, the precursor is preferably a linear polymer or cellulose ether such as lly~lu~ylulu~!yl acrylate/llydlw~yc~llyl acrylate copolymer.
Aslû, the water-based fluid used to make the gel can include sucrose in the range of 30% to 60% to vary the reaction ttlll~..dLulc.
The invention is also directed to the use of a polyurethane gel that provides 3û a highly flowable v;,.ucld,L;. medium and does not require a gel bladder. Thepolyurethane gel can be provided in various hardnesses to provide proper mediumsfor shoe comfort, including fit and ~l~hinnin~. The polyurethane gel is preferably W096~28057 2~9~2~5 ~ tQ~:
a soft elastomer with high sol (plasticizer) fraction which can include a high molecular weight triol (MW greater than 6000) and a L~ OLyd~ C. The polyol can be made of Arcol E-452 and the plasticizer can be a Paraffin oil or diproylene glycol f~ Pn7(~rP
In another embodiment of the prQent invention, the flowable v;,.u.l~;c gel is a butadiene style rubber which can be prepared from oil and poly;,ubuL~l;...e.
Preferably, oil such as Kaydol and a styrene ethylene butadiene styrene triblockmedium molecular weight rubber polymer such as Kraton 1650 M Kaydol is a paraffin (55Yo) and rlaphtenic (45Yo). By increasing the percentage of Kraton, the 10 firmness of the gel can be increased for various locations where a firmer gel is desired Still further, plastic, expanded, resilient, hollow microspheres such asE~pancel 091 DE80, expanded glass hollow l~u~u~l~..Q or a blowing agent can be added to the gel to reduce weight or the gel can be frothed with air using ultrasonic cavitaticin.
Still further, the foam can be comprised of a polyurethane foam with hollow ~P~u~ c~ or a blowing agent. In another embodiment, a memory foam can be comprised of a polyol, antifoam agent, catalyst and Ioscyanate The invention is directed to a shoe that conforms to the foot contours by UILOI~JL~ ; a shoe upper that is comprised of three layers; the shoe outer layer, 20 the shoe inner layer, and LUllrUlUUllg layer LII..CIJ~ The ~u~rullll;llg layer can be comprised or portions made from highly flowable, viscoelastic gels, foam and t~ Lu-c-rQponsiVe gels. Preferably, the invention includQ soft, highly flowable v;~Lùel~;L gel provided in areas of the shoe that ~ullc~ond to those areas of the foot that are generally highly contoured or have greater curvature for better fit and ~5 comfort. In areas where stability or shock cushioning is dQsired, a more viscous (IQSS flowing gel) is used and in areas where fit and comfort are required, a softer, less viscous (more flowing) gel is used.
As stated above, the invention can also include a Lc...~ u.c-responsive gel that reacts to the heat dissipated from the foot inserted into the shoe to exprQs a0 liquid that will fill a bladder to allow the show to further conform and provide "; ~ and securing fit for the foot therein WO 96128057 2 1 9 0 2 5 5 . PCT/[JS96/03480 Further, the invention is directed to a shoe ;llc~ OI~L;.~g a tongue which can have portions made from higllly flowable, viscoelastic gels and ~elll~4Lulc-responsive gels to provide a ~ cr~mi7~-~1 fit and ~Ichionin~ to the top of the foot that has been inserted into the shoe.
Still further, the present invention is directed to a shoe which conforms to the foot by providing a foot bed comprised of v;a~Jel~;c gels and/or ~tlll~ Lulr~
responsive gels therein to conform to and provide ~uallioll;llg for the foot bottom.
Preferably, the shoe foot bed is formed of a low-flowable, harder gel such that it provides supportive cushioning for the foot bottom, for absorbing the impacts ofwalking and the like. Further, the foot bed should provide a soft, highly flowable gel to provide custom fit and comfort for the foot and, particularly for the foot arch and heel. This is preferably ~ with the proper placement of various ~l~cr~lm~rj~ gels having proper hardness and viscosities to provide comfortable and supportive v;a~Jcl~L;C mediums against the foot. Still further, the foot bed is formed with the combination of gels ~n~rc~ t. ~l in a polyurethane foam or preferably a memory foam matrix. This provides ..,~ .lc fit, comfort, cushioning and stability all in the same system.
The present invention is ~Iso directed to a method of forming a . ,,~I~..,.;,-.lfitting shoe. The method includes forming a shoe upper which is comprised of the20 steps of molding flowable, v;~. o~ ;c gel and foam to form a ....lr... ,.,;"g layer of a shoe upper. Preferably, the method of forming a . ,.~1..,..;, .~ fitting shoe upper is comprised of the steps of pouring flowable v;a~ucl~;~ gel into proper locations of a mold, pouring polyurethane foam or memory foam ;II~;lel;~llLa into the mold, closing the top of the mod which can have the shoe inner layer attached thereto,25 heating the mold a removing the gel, formed foam and shoe inner layer. Then a~rll~ U.e-responsive gel and bladder containing the same can be placed in properlocations and an outer layer can be attached to the opposite side of the .
layer from the inner layer.
Still further, the method includes forming a ~elll~ ule-responsive gel and 30 bladder by vacuum forming an d~ ely 10 mil thick plastie bottom film into a mold, placing a die cut Lél~ Lu~c responsive gel which is at a relatively coldklll~ Lule into the mold cavity, placing a flat top layer of d~plu~;ul.~ly 5 mil WO 96/28057 2 1 9 ~) 2 5 5 PCTIITS96/03480 thick plastic film over the mold, att~ching the top and bottom films using radiofrequency or other method.
Even still further, the present invention is directed to a method of forming a shoe foot bed ~u~ ;a;llg the steps of pouring relatively hard, high viscosity,5 v;~u.l~L;~ gel into the foot bed heel plug section of a mold, pouring a relatively soft, highly flowable, v;~u.l~L;c gel into proper locations of the mold for providirlg a ~rull~ fit and comfort, pouring polyurethane foam or memory foam iU~ d;..l~ into the mold, covering the mold with the mold top, which can have the foot bed cover fabric attached thereto, and heating the mold.
In another aspect of this disclosure, the shoe ;ll~ull~OldLe~ a reversibly gelling polymer network exhibiting a dramatic change in viscosity in response to a change in an C:llV;lUlllll..lLdl stimulus. The reversibly gelling polymer network may contain a responsive ~olll~ul~ capable of aggregation in response to a change in ~llVilUlllll.llLdl stimulus and a structural .Ulll~Ull..lL which supports and interacts 15 with the responsive ~ulllpOll~.lL in an aqueous-based solvent. The reversibly gelling polymer may be a triblock polyol of the general formula (EO)(PO)(EO), either alone or prepared according to the invention in the presence of other gel polymers.
As used herein, as responsive ~ulll~Oll~llL is an oligomer or polymer which will respond to a stimulus to change its degree of association and/or agglomeratiorl.
20 The stimulus may be Ltlll~7..dLul~, pH, ionic ~u~ L~dLion, solvent ~u~ lLI~Lion, light, magnetic field, electrical field, pressure or other triggers commonly used to trigger a responsive gel material. The ~ ,.sLiull may be in the form of micelle formation, precipitation, labile crosslinking or other factors.
As used herein, the structural ~UIII~/UlI..IL is an oligomer or polymer which 25 supports and interacts with the responsive ~UIII~JUII~ 50 that a multi-material, responsive polymer network is formed. The structural ~ull~o~ L is not required to be responsive. The interaction of the structural and responsive ~u~ ol~.llL~,exhibits a synergistic effect, which magnifies the effect of the responsive " 'l"'~ ' in v;~u~;ry;llg and/or gelling the solution. It may also cause a sol-gel transition to 30 occur under conditions which would show no apparent effect in the absence of the polymer network.

In the absence of the structural ~ the responsive w.ll~uo~ may or may not show a change in viscosity in response to a change in CIIV;IUIIIII~..I~;II
stimulus. Ho vever, if it does show a response in the absence of the structural ...",1..~l.. .~1, that response is uuli-a-;~.ly or uu~ a~ ly different. That is, the 5 response is amplified or altered ;n the presence of the structural ~UIU~oll~.lL~.
The responsive and structural ~uulluull~ are dissolved in an aqueous-based solvent. Since a gel comprises a three-. l; " ....ci -l .al polymeric network dissolved in a solvent, the liquid . .,",l,~ makes up the responsive polymer network.
The novel interaction between the ~ polymers in the responsive 10 polymer network permits formation of gels at very low solids content. Gelation and/or v;,~ r;. ~ n is observe~ in aqueous solutions having about 0.01 to Z0 wt%of the responsive ~UI~ bll~ and about 0.01 to 20 wt% of the structural Culll~ull..l~.
A typical reversibly gelling polymer network may be comprised of less than 15 about 4 wt% of total polymer solids of which less than about 2 wt% is the responsive ~ull.~o~ and less than about 2 wt% is the structural ~ulllluOll~ . The balance is made of the aqueous based solvent. An exemplary responsive ~UIlll,or.~
is a triblock polyol having the formula (EO)(PO)(EO). An exemplary structural UUlll~JUmll~ is sodium acrylate which is m~mlf~tllred by polymerization of acrylic 20 acid in the presence of the triblock polyol followed by hydration and neutralization of the polyacrylic acid. The viscosity of the gel increases at least ten-fold with an increase in lelll~L..1~UI~: of about 5C.
By "gelation", as that term is used herein, it is meant a drastic increase in the viscosity of the solution. Gelation is dependent on the initial viscosity of the25 solution, but typically a viscosity increase in the range of 5- to 100-fold, and preferably 10- to so-fOld, is observed in the present systems. The gelled state has sufficient m ~h~nir~l strength to conform and provide support to the foot.
By "triblock polyols", as that term is used herein, it is meant a polymeric or oligomeric structure having a general formula of (Pl) (Pz)~(Pl)l, where Pl and P2 30 represent two different polyol blocks. By way of example only, P~ may be a polyol of the general formula (CH2CH2O)~, where a is in the range of 10-50 and P2 may be a polyol of the general formul~, (CHRCHRO)~, where R may be H or W096128057 ~1 90255 PCI/lJS96/03480 an alkyl group, and where b is in the range of 50-70. Other possible polyol are ~ within the scope of the invention.
The reversibly gelling polymer network may be ;ll~ul,uulaLed into the shoe as described herein above and below for the ~lvilull~ Ldlly responsive gel. That5 is, the reversibly gelling polymer gel network may be ill~u~t~uld~d into the shoe upper as a ~..,.r~ g layer. The .~ layer may additionally comprise highly flowable viscoelastic gels and/or foam. The reversibly gelling polymer gel network reacts to the heat dissipated from the foot inserted into the shoe to undergo a reversible change in viscosity to form a gel within a bladder housed 10 within the shoe upper which allows the shoe to further conform and provide ~u~llioll;llg and securing fit for the foot therein.
The present disclosure is further directed to a method of forming a r~lcrr~mi7~ fitting shoe. The method includes forming a shoe upper by molding flowable, v;~ u.l~sL;~ gel and form to form a ~ullrullllill~ layer of a show upper, as 15 described h~cul.~buv~. Then a reversibly gelling and a bladder containing the same can be placed in the proper locations and an outer layer can be attached to the opposite side of the ~. ..,r.~ g layer.
A reversibly gelling polymer gel network and bladder may be formed by providing a lower and upper plastic film, filling the mold with the reversibly gelling polymer in a cooler liquid or warmer viscous state into the mold and sealing theassembly.
In another aspect of this disclosure, a sys~em for proving support to the human foot is provided which includes a thermally responsive polymer gel contained in a polymer membrane of limited water solubility and located within an article of footwear. The. thermally responsive gel exhibits a dramatic change inviscosity in response to a change in ~L.Il~ Lult around the use Lel~ Lulc. The thermally gelling polymer is designed to be fluid below the expected use temperature and to increase viscosity or otherwise provide support when the gel is exposed to the use Ltlll~ ull:.
As used herein, the expected use L~ Lu- = is the tcl-l,u~. ~Lul c~ to which the gel.bladder system will normally be raised due to heat evolution by the foot. It is WO 961280s7 2 1 9 0 2 5 ~ r expected that the concept of thc expected use ~t~ UlC will involve a transition range of the gel. In other words, for a system normally expected when the foot is rlot present to be at room ~tlll~ UlC, "below the expected used ttll~ -UlC"
might mean ~ u.c~ at or below 26.67C while "above the expected use 5 Ltl..~ u.c" might mean ~tlll~.d~u.ca at or above 32.22C. The preceise rlumerical values of below and above the expected use ~tlll~ UIc are d~ ;UII
arld system specific. In particular, different parts of the foot can develop different levels of heat and so systems designed for different parts of the foot will havedifferent values of the expected use temperature. It is recognized that individuals 10 have different body ~tl~ Ul~ and the gels will have to be tailored to these individuals by adopting the transition range of the gel.
Also as used herein, a gel composite is a structure which contains at least two ~UIII~UII..I~: 1) a solidus portion through which a fluid can migrate through conveaion or other mass transfer mrthnrlnlofy and 2) a reversibly ~u~rul~ ble gel.
A specific example of a gel composite would be an open cell foam structure ;ull.lt~ Ltd with a reversibly ~ullrullll~ble gel. In this case of this ;lll~ t.;l form, below th eexpected use temperature, the gel can flow freely through the pores of the foam providing a soft malleable structure, while above the expected use ~.IU~ -Ulc7 the increase in vicosity prevents the fluid from flowing through thepores of the foam providing a much more rigid ~u~o~l;llg structure.
The minimum useful support viscosity is defined as the applications .~rtr~ minimum viscosity of a thermally reversible polymer gel above the expected use tCl~ UlC which viscosity will enable the system to provide the necessary fit, comfort, support and/or m~l h~ni~l protection to the foot.
The maximum useful flow viscosity is defined as the applications rlr~tr rminr~d maximum viscosity of a thermally reversibly polymer gel below the expected use ttlll~ u. c which viscosity will enable the gel in the system to flow and ICd;~llLlU~C itself readily.
Bri^f Description of the Draw;n~
Figure 1 is a l,..*,.~ ~;vc view of a shoe according to the present invention and lll~Ul~Ul~ g a ~tlll~ ul~-responsive gel and bladder for the same;

WO 96/28057 2 ~ 9 0 2 5 5 PCT/US96103480 Figure 2 is a p.. ~Live view of a ~Ull~UIllUllg layer of the shoe according to the present invention;
Figure 3 is an enlarged, cross-sectional view of the Lclll,u., .~UI e-responsive gel bladder in the shoe upper;
Figure 4 is a cross-sectional view of the heel of a shoe according to the present invention incorporating v;,~ucl~;~ gel and foam therein to conform to the foot;
Figure 5 is a cross-sectional view of the ~culy~ ule-responsive gel and bladder in the expanded state;
Figure 6 is a cross-seaional view of the te~ ule-responsive gel and bladder in the contracted state;
Figure 7 is a top view of the ~u.~u....;.~g layer of a shoe tongue according to the present invention;
Figure 8(a) is a top view of a foot bed according to the present invention;
Figure 8(b) is a side view of a foot bed according to the present invention;
Figure 8(c) is a bottom view of a foot bed according tO the present invention;
Figure 8(d) is a sectional view taken along the line XX in Figure 8a;
Figure 9(a) is a top view of a second embodiment of the foot bed according to the present invention;
Figure 9(b) is a cross-sectional, side view of the second ~ ,o l;~". .,1 of the foot bed according to the present invention;
Figure 10 is a flow chart of the method used tO construct the shoe upper according to the present invention;
Figure 11 is a flow chart of the method used to construct the foot bed according to the present invention;
' Figure 12 is a graph of viscosity versus ~elll~ Lule for a 1 wt%, 2 wt% and

3 wt% reversibly gelling polymer network cc.mro~ n of a triblock polyol/polyacrylic acid (1:1) at pH 7.0 measured at a sheer rate of 0.44 sec-l;
Figure 13 is a plot of ~n~ tl~rm~ for a (a) 1 wt% Pluronic F127 and (b) 1 - wt% reversibly gelling polymer networks ~OIll~u~;L;Oll of Pluronic F 127/polyacrylic acid (1:1);
. 9 WO 96/28057 ~ A 7 ~
Figure 14 is a viscosity versus Lt~ ulc curve of (a) 17 wt% Pluronic FlD
and ~) 17 wt% Pluronic F127 in lwt~ llydlu~ye~llyl cellulose measured at a sheer rate of 1 rpm;
Figure 15 is a viscosity versus ~tlll~,diUlC curve for 17 wt% Pluronic F127 5 measured at a sheer rate of 1 rpm;
Figure 16 is a viscosity versus ~tlll~.d~UlC curve for 30 wt% Pluronic F68 with increasing amounts of sodium chloride measured at a sheer rate of 0 3 rpm;
Figure 17(a)-(c) are cross-seaional views of bladders for use in the present invention;
Figure 18 is a ~tl~ .. d~UlC versus wt% curve for Pluronic F127 illustrating gel domain;
Figure 19 is a ttlllt/~.d~UlC versus wtYo Pluronic F68 curve illustrating gel domain;
Figure 20 is a temperature versus wt% Pluronic P103 curve illustrating gel domain;
Figure 21 is a ~tlll~ld~UI~ versus wt% Pluronic P105 curve illllctratin~ gel domain;
Figure 22 is a ~CIlllJ~ld~UlC versus wt% Pluronic F87 curve illustrating gel domain;
Figure 23 is a tCIII~.ld~UlC versus wt% Tetronic 904 curve illustrating gel domain;
Figure 24 is a ~CI~ .d-UlC versus wt% Tetronic 908 curve illustrating gel domain;
Figure 25 is a ~CIll~.ld~UlC versus wt% Plurafac A38 curve illustrating gel domain;
Figure 26 is a ~tll*~.d~UlC versus wt% Plurafac A38 curve illustrating gel domaun;
Figure 27 is a ~CIll~ld~Ul~ versus wt% Pluronic F108 curve illustrating gel domain;
Figure 28 is a Lcl~ .d~UIc versus wt% Pluronic F88 curve illustrating gel domain;

WO 96128057 r~ u... ~.'^7 .
21 902~
Figure 29 is a plot of viscosity versus ~t~ Lulc for a 1 wt% reversibly gelling polymer network composition of Pluronic F88/polyacrylic acid (1:1) at pH7.0 measured at a sheer rate of 2.64 sec-' with a SC4-18 spindle; and Figure 30 is a plot of viscosity versus ~ u~c for a reversibly gelling polymer network ~U~pO~;~;oll of 2.5 wt% Pluronic F127/polyacrylic acid (1:1) prepared in (a) deionized water and (b) 0.5 M NaCI solution.
Description of the Preferred r.. l,~-.1;,.. ~
~eferring to Figure 1, the preferred ~mhnrlim~nt of the present invention is a shoe 10 that incorporates a shoe upper 12 and a shoe sole 14. Inside the shoe 10 and no~ shown is a shoe mid-sople. The shoe upper 12 is comprised of an outer layer 20 and an inner layer 22. In between the inner and outer layer is a ~ullr~ flllg layer 24 as disclosed in Figure 2. In the preferred cl~boJill~ the inner layer 22 is made of brush nylon or leather and the outer layer 20 is made of leather.
The ..",f."...;.,y layer 24 in Figure 2 is comprised of a first flowable v;,~u.l~;c gel portion 50, a second ~tlll~ ulc-responsive gel portion 30 and itsbladder 32 and third foam portion 40.
The v;~ucl.w~;~ gel section 50 is preferably comprised of a flowable 20 v;~ucl.w~;~ gel that is ;ll~u~ le, i.e., it retains its volume upon ~ulll~lc~;ùn.
Therefore, this material, when CulL~Ic~cd by pressure from the foot inserted into the shoe, will flow into another location where the pressure is not as great. In the preferred clubod;lll.~ the v;~u.l~;~ gel is molded into a body section 54 and a plurality of connected fingers 52. This enables the viscoelastic gel 50 to conform 25 the foot inserted into the shoe. And as one skilled in the art would appreciate, the v;l~ùel~;c gel section 50 can be molded in many shapes. However, in the preferred .. 1~.. 1;.. ,~ the viscoelastic gel 50 should be molded into areas of the shoe which ~Ol l ca~ulld to highly contoured areas of the foot. For instance, the heel of the foot generally tends to be very contoured and, therefore, the v;~uel~ gelsection 50 is preferably located so that the shoe can sllhct 1nti~11y conform the foot heel. Thus the v;~u.l~;c gel 50 preferably extends to correspond to the heel bone and malleoli bones of the foo~.

wo 96/28057 2 1 ~ 0 2 5 5 . ~ I, ~, ~
Preferably, the viscoelastic gel is comprised of a ~olyulc~lldlle gel, but othergcls which disclose the desired properties of elasticity and flowing nature can also be used. In the shoe upper, the viscoelastic gel is preferably of a relatively soft, highly flowable gel. That is, the gel has a -000 hardness of d~lu~d~ cly 10 to 100 5 and preferably about 40. Moreover, the v;~.l,.l~;. gel portion can be formed of various hardnesses to best conform to the foot. For example, the body section 54Cdn be made from a soft gel of dlJ~Iu~dllld~ely 40 to 60 -000 hlrdness and the extending fingers can be made from the same gel hardness or a gel having a lowerhardness and being more flowable.
Another advantage to using a viscoelastic gel is that the gel does not need to be f nf~rs~ rP~ into a bladder, i.e., the gel is not surrounded by a plastic liner to limit the flow thereof. Since the preferred material is a flowable gel, it can be formed directly between the frol1t and back layers 20 and 22.
In one embodiment, the flowable v;~.ocl~L;c gel is a soft elastomer with 15 high sol ~ ;. ;~l) fraction which can include a high molecular weight triol (MW
greater than 6000) and a diisocyanate. The polyol can be made of Acrol E-452 brand polyol and the plasticizer can be a Paraffin oil or d;l~lul~yl~.lc glycol f~ihf n7n~rf~
In another embodiment, the flowable V;~ d~L;C gel is a butadiene style 20 rubber. The rubber can be prepared from oil and polyisobutadiene. Preferably, oil such a Kaydol and a styrene ethylene butadiene styrene tri block medium molecular weight rubber polymer such as Kraton is used. More preferably, 60 ml of Kaydol and 7.5 g of Kraton 1650 M are mixed and heated to 140 F for one hour. The material is stirred twice during the one hour and then poured into a cool and set 25 into a gel. By increasing the percentage of Kraton, the firmness of the gel can be irlcreased for various locations where a firmer gel is desired or vice versa. Still further, expanded, resilient, plastic, hollow Ill;~lU~ C~ such as Expancel 091 DE80, expanded, glass microspheres or a blowing agent can be added to the gel toreduce the weight of the gel. Still further, the gel can be frothed with air using 30 ultrasonic cavitation or "". A~ f.l Expancel DU grade Illi~l~,a~h~c~ can be used ~nd ~.~nded durinG proce~ing. 1~

WO 96128057 2 1 9 Q ~ S 5 r~
A lc.l.~.. dLulc-responsive gel is described as a crosslinked three .l;".. ,~:.".~l polymeric network that contains a substantial quantity of liquid so that the properties of the gel are ~ by both the polymeric network and the liquid.
If the liquid is water, ~he gel is commonly called a "hydrogel." The volume of this 5 type of "reactive gel" may contract by a factor of up to several hundred percent when the gel undergoes a change in external conditions, such as ~tl~ dLule, Ph, solventorsolventcon~ntr~rion,ionic~o.l....L.dL;on,light,pressureorelectricfield.Preferably, the gel used for this application is of the type that reacts to té~ dLulc and/or pressure and recovers once the external condition is removed.
The network material of a responsive hydrogel as used in the preferred c~b~d;~ L~ may be comprised of a number of polym~ric materials that possess a lower critical solution tClll~..dLUlC (LCST). The term LCST is the Lc...~..dLIl.c below which the polymer is 5~ c- ~nti~lly soluble in liquid and above which the polymer is 5~l1 st~nri~lly insoluble. Therefore, the responsive gel forms a two phase 15 system.
The preferred tclll~ldLul~responsive gel portion 30 is comprised of a hydrogel gel. Examples of gels are given in U.S. Patent No. 5,183,879 and PCT
Patent Application No. PCTUS94/05400 which are ;ll..~ .dLcd herein by reference. The preferred lc~ ..d~u~c-responsiVe gel contracts upon application of 20 heat from the foot inserted within shoe 10 and thereby extracts water from the gel.
As the shoe tClll~..dLu.c rises from the foot that is inserted therein and movesduring normal aaivity, the gel contracts. Therefore, the tclll~ ulc-responsive gel section 30 can be located anywhere in the shoe to assist in t l~nformin~ to the foot contours, but, preferably, is located at the shoe mid-section which generates 25 substantial heat. The gel bladder 32 is used to contain the water solution 34 that is expelled from the contracted gel and allows the water solution 34 to flow around and conform to the foot that is inserted into the shoe. Preferably, the bladder 32 extends from the quarter 35, around the collar 36 to the achilles tendon area 38 for providing support for the collar, which assists in ."~;,.l~;l.;,.~, the foot within the 30 shoe, and for assisting in protecting the achilles tendon.
Referring to Figure 3, an enlarged section of the gel bladder 32 is shown in a cavity 32c formed between the outer layer of shoe material 20 and the inner layer .

WO 96/28057 2 1 9 ~ 2 5 ~ PCT/US96/03480 of shoe material 22. In the preferred ~ mhoflim~nt~ the gel bladder 32 is extended from the L...l~ld~u.c-responsive gel portion 30 in the quarter 35, around ~he collar 36 to the achilles tendon section 38 such that water solution 34 can be rli~trihllt,od from the midsection of the foot towards the heel location and allows the shoe to5 better conform thereto as the shoe is heated.
In this ~IIIbU~ 7 the ~c~ d~u~c-responsive gel in the shoe is an cllv;lulllll..lLally-responsive gel. An c..v;.u...l.,.l~dlly-responsive gel is a ~u~u~uoluu~,fastresponsive,crosslinkedgelobtainablefromapolymericprecursor, the gel being of sufficient flexibility to enable the gel to be reversibly responsive to 10 a change in an cllv;lulllll..l~al condition such as ~tlllp.ld~UlC, The gel can be made from any responsive polymer with side groups that can react with a di- or multi-functional crosslinking molecule. The polymers can have hydroxyl, acid or amine side groups and which have lower critical solution ~tlll~J..d~UlC~7 in aqueous solutions together with water-soluble crosslinkers. Even more particularly, the gel 15 is preferably a ~t~ ..dlu~c-reSponsive gel and is able to undergo a phase separation or phase transition which is Ltll~ d~ule induced. Still further, the precursor is preferablyalinearpolymerorcelluloseether,andmorepdl~;.uld.ly,llyliu~y,ulu~yl acrylate/llydlu~yetllyl acrylate copolymer. Preferably the llydlul~y,ulu~yl acrylate/llydlu~Lyallyl acrylate copolymer gel is comprised of between 50 to 10020 percentllyd.u~y~.u~,ylacrylateandbetween50toOpercentllyll.u~ycLIlylacrylate.
Also, the water-based fluid used to make the gel can include sucrose in the range of 30% to 60% to vary the reaction ttlll~J..d~UlC, Further, to enable the tclllp..dLulc-responsive gel to operate at lower ~tlll~l..d-UlC~, glycerin or glycol can be added to reduce the freezing ~ J..d~UlC of the solution.
The foam portion 40, which makes up the remainder of the ~u.lru.. Lulg layer 24, can be made of many standard foams that are available. The foam portion 40, however, is preferably made of a memory foam, i.e., a foam that deforms upon~u.ll~lc~;oll and once the press~re is released, will slowly return to its original position. The foam portion 40 is preferably made with to a Shore C hardness of 30 ~lu~dllld~cly 25. The form portion 40 is used to surround and secure the flowable, v;~u~ L;C gel portion 50 and the ~t~ J,.d~u~c-reSpOnSiVe gel portion 30.

W096/2~0s7 2 ~ 902~5 T~l/1) 6N`~
The foam portion 40 can be comprised of a polyol, antifoam agent, catalystarld Isocyanate. Still further, lhe memory foarn can be formed from d~lU~ ly 58% Arcol LG168, d~lU~ dLCIy 1% water, d~J~lu2dlll~dLely .5% Dabco 131, ~lu~ Lely .5% Dabco 33LV and d~J~lu~dlll~Lely 40% Isocyanate 2143L.
Figure 4 discloses a cross-section of the preferred embodiment of the shoe heel wherein the plurality of viscoelastic fingers 52 are disclosed extending in the vertical direction up the shoe heel so that the v;~l uCI~L;C material can conform to the foot that is inserted therein. The ~;~.u.l~L;c fingers 52 are molded and then Pn~rslll~t~l by the foam material 40. The fingers extend into the concave contours of the foot heal to provide a more securirlg fit.
The Lelll~dLulc-responsive gel 30 and gel bladder 32 are shown in the expanded or cool state in Figure 5. As stated above, the ~elll~ UI c-responsive gel 30 is expanded at t~ ,.d~UlC~ below the lower critical solution ~tlll~..d~ule, which should be between d~lU~lUd~ely 60 to 90 degrees Fahrenheit. In the expanded 15 state the gel contains a water-based solution therein. Thus, the bladder 32 is relatively empty when the gel 30 is expanded.
The Lelll~..dLul~reSpOnSiVe gel 30 and gel bladder 32 are shown in the contracted or heated state in Figure 6. The telll~.~dLulc-responsiVe gel 30 is heated due to the heat emitted from the foot inside the shoe. As the ~ell~ ulc-responsive gel 30 is heated above lower critical solution Lel~ dLulc the gel contracts and the water solution 34 therein is expressed from the gel and into the bladder 32. Thus, the water solution 34 dynamically flows to areas under less pressure as the shoe is heated. This enables the shoe to dylldlll;~lly conform to the foot that is inserted therein.
As the lelll~dLulc-responsive gel 30 cools when the foot is removed from the shoe the gel expands and retracts the water solution 34 from the bladder 32.In other words, the ~tlll~ld~ule-responsive gel 32 returns to its expanded state as shown in Figure 5.
Figure 7 discloses the preferred ~mhorlim~nt of the shoe tongue . ~ r ., I~
layer 60. The shoe tongue 16 is shown in Figure 1 and is attached to the shoe 10such that i~ covers a portion of the top of the forefoot that is inserted into the shoe 10. The Cùllrulllullg layer 60 is preferably comprised of a ~clll~.d~ulc-responSiVe W0 96/280s7 . ~
gel portion 62 including gel bladders 64 extending thereabout, a viscoelastic gel portion 66 and a foam portion 68 enveloping both of the gel sections 62 and 64.
The tongue . I ,.r-. ,.,;"~ layer 60 is enveloped by an inner layer and an outer layer (not shown) sllhQt~nti~lly similar to the inner and outer layers of the shoe upper discussed above. The shoe tongue is then attached to the shoe upper along the bottom edge 70.
Figures 8(a)-8(d) disclosQ a foot bed 80 incorporating a foam main body section or foam pad 82, a plurality of relatively soft, flowably v;a~ucl.aL;C gel sections 84, relatively soft, flowably viscoelastic gel fingers 86 and a relatively hard, 0 v;a~ucl~;~ gel heel plug insert 88. Again, the v;a~u~ ;c gel sections could be located anywhere in the foot bed, but are preferably placed such that the relatively soft, flowable gel ~u~ uullL to those sections where the foot has the greatQt contours and the relatively hard, higher viscosity gel ~ullQIuo~ to where the foot is subject to the greatest impact from walking, running or other activity. Thus, in the preferred ~mho~lim~nt the v;a~,OCI~L;~ gel section 84 and fingers 86 correspond to the foot arch area and extend around to the areas that correspond to the footheel. The gels are again made to a -000 hardnQs between 10 and 100 and preferably in the range of 40 to 60.
The v;a,uCI~L;C gel heel plug insert 88 is preferably located in the bottom of the foot bed to provided cushioning and shock absorption for the foot heel.
This insert is preferably made of a gel having a -000 hardness between 20 and 60and more preferably of d,UUl U~ ly 40 to 50. The viscoelastic heel plug insert 88 preferable includes a plurality of ribs 89 to provide additional ~chinning, and absorption of shock for the foot heel.
The foot bed 80 also includes a foam heel plug 90 which is preferably formed of the same foot bed foam as the main body 82.
The preferred foot bed 80 also includes a plurality of groovQ 92 that allow the flowable v;a~uLloL;c gel to extend up the back of the heel and that increase the flexibility of the foot bed 80. These groovQ 92 are shown as extending around the outer edge of the foot bed and c~hct~ntillly in the vertical direction to provide proper flexibility of the foot bed.

WO 96/28057 2 1 9 0 2 5 5 P~"`'~--~
Figures 9(a)-(b) disclose a secorld ~l~lbud~u~llL of a foot bed according to the present invention. The foo~ bed 81 includes the highly flowable viscoelastic section 84 and fingers 86 and the harder viscoelastic heel plug 88. The foot bed 81 further includes a metatarsal pad 94 with ribs 96 for providing cushioning to the foot. Still 5 further, the foot bed includes wing members 98 with gel sections 100. These gel sections 100 can be made of the Lt~ Lul~reSpOnSiVe gel and the water solution therein can flow in fingers 102 or the gel sections 100 and the fingers 102 can be made of the highly flowable v;,~oel~L;~ gel. This provides a, ~ ~l..".;,. .1 fit for the fore foot. Moreûver, the wing members 98 can be provided with different lû thirkn.occ~ c so that the customer can chose one that provides the most ~u..~lLable fit. Figure 10 presents a flow chart of a method of forming a I .".r~.. ",;,.~ shoe.
The steps include forming a ~ul~f~ull~ g shoe upper, as shown in Figure 2, or tongue, as shown in Figure 7, by pouring flowable, viscoelastic gel and foam lu~ d;. .~L~ into a mold to form a those portion of the ~- ,., ro. . ";, .~ layer of the shoe 15 upper or tongue. Preferably, the v;a~oel.~ gel is poured irlto the proper locations of a mold and then the memory foam ;II~;ICU;~.IL~ are poured into the mold to fill the same. I'he inner layer of the shoe can be placed in the bottom of the mold before the gel and foam are poured therein such that the gel is formed orl the inner layer. However, the preferred method is to attach the shoe inner layer to the top 20 plate of the mold. The mold is closed with the top plate and the mold is heated.
Heating can be ~r~mlllichl~l by heating either the mold or the mold top or both to solidify the gel and foam. Thus, the flowable, viscoelastic gel and foam are molded onto the shoe inrler layer.
The L~lU~ Lu-cresponsive gel is formed separately from the viscoelastic gel 25 and foam. The ~tl~ Lu~responsiVe gel cassette and bladder are formed in a separate mold. A first layer of plastic film is placed into the mold. Preferably, the plastic film is about 10 mils thick and is a polyurethane film or a laminated film such as surlyn/polyethylene laminated film, to increase the water retention in the gel bladder. This film is vacuum formed over a cavity that is d~J~JI u~;lll~tely 4û to 30 80 thousands of an inch thick. The responsive gel material is added at a relatively low ~tlll~ Lul~ preferably around O degrees celsius to keep the gel saturated with the water-based solution. Then a flat top layer of plastic film is laid over the mold.

WO 96128057 PCT/US96~03480 21 ~0255 The top layer is preferably about 5 mils thick and formed of a polyurethane filmor a larninated film such as surlyn/polyethylene laminate. The top and bottom layer films are then bonded by radio frequency bonding or other method.
The . .."r(,. ,.,;,.g layer of the shoe upper or tongue is completed by placing 5 the Lc~ .dLulc-responsive gel and bladder containing the same in the proper locations and attaching the shoe outer layer to the inner layer such that the ~ullrullll;l~g layer is between the outer layer and the inner layer.
After the shoe upper or tongue is formed, it is attached to the shoe in an ordinary manner.
The invention also includes another method that can be used to form adjacent regions of foam (polyurethane or other foam) and v;~ueld~L;c gel material.
In this method, the foam and gel can be chemically bonded or unbonded and merely adjacent. More pdl L;~ul~lly, the method includes the steps of pouring foam material into a mold. Then v;~uCI~L;C gel with u,.. .lIAII~I. .l llu~lua~h~c~ can be 15 injected into the mold cavity by a separate operation. The mold is then heated to a L~ .dLulc above the expansion t~ ..dLulc of the Illi~ lu~ c~. Depending on the tC~ J..dLUlC the mold is heated to, the expansion of the llu~lu~ c~ can be controlled to vary the pressure in the molded part.
Referring to Figure 11, a shoe foot bed, as shown in Figures 8(a)-8(d) or 9, is formed by pouring relatively l1ard, high viscosity, viscoelastic gel into the foot bed heel plug section of a mold, pouring a relatively soft, low viscosity, V;~CUCld~L;~
gel into desired locations that can include the arch area and sections around the foot heel and pouring a foam ingredients into the mold and covering the mold with themold top with the foot bed cover fabric attached thereto and heating the mold.
The reversibly gelling polymer network exhibits flow properties of a liquid at about room Lclll~..dLulc, yet rapidly thicken into a gel consistency of at least about five times greater, preferably at least about 10 times greater, and even more preferably at least about 30 tirnes and up to 100 times greater, viscosity upon exposure to the particular ~llv;lu~ l trigger. The thermally reversible gelling 30 polymer may comprise a single polymer which responds to changes in ~tlll~ UlC.
In particular, the reversibly gelling polymer may be a triblock polyol.

AlLt.lldli~ .ly, the responsive polymer network of the present invention may comprise a polymer-polymer ~mrociti..n in which the two or more polymer phases are mutually interacting without covalent bonding between the two polymers. The interaaing nature of the two (or more) polymer phases provide a S Stdble miscible r~mro.:tinn, ;..Q~f~L;~. of the immiscibility of the ~
polymers, and unique properties. Such stability and properties may be attributedto specific ;~ d~L;ull5 of the ~u~ ;LucllL polymers.
The responsive ~u-l-l o~ undergoQ a change in cu.lru.,....,;on in solution.
One type of responsive UIIl~UII~ is a ~t...t,..dLu-c-sensitive ~.~,b..b.~Li-.~ polymer.
10 A~t~llu.ldiulc-sensitive..~,bl~;d~ gpolymerundergoesctnfrltrn~ti-~nalchangesand changes to the critical micelle ~on.t..L.dL;ol1 as a funaion of ttlll~.ldLulc. The polymer will change from an open, non-aggregated form to a micellular, aggregated form with changes in L~ Lule.
The struaural ~UIII,uOI~ may be a polymer which is capable of ionization 15 with a change in ionic strength of the solution. Changcs in ionic strength may be ,f.I by a change in pH or by a change in salt ~ ,. f~ ChangQ to the ionic state of the polymer causes the polymer to experience attraaive (collapsing) or repulsive (flrranfling3 forces. Because of the hydrogen-bonding capability of these ionizing polymers and of the responsive UlllpOll..lL, it is20 hypothesized that the formation of the polymer network of the invention involves molecular interaction and, in particular, hydrogen bonding interaaion between the polymers. Ionization is not required, however, and the structural u..l,uull..lL may be neutral or uncharged.
The responsive polymer network of the present invention may be prepared 25 as an aqueous gel composition, which exhibits a reversible gelation upon exposure to a change in an cllv;lulllll~llLal stimulus. Suitable cllv;lul~ llLal stimuli which may be used to initiate gelation include pH, Lclll~.laLulc~ ionic strength and solvent c~mrn~itinn The responsive polymer network may exhibit a reversible gelation in response to one or more ~lv;lul~ Ldl changQ. The gelation may occur in 30 rQponse to an indirea CllV;lUlllll.~ l trigger, for example, light irradiation or - elearic field arplifati~ln which generatQ an increase in Lt---~ Lu~e. Responsive polymer network gel compositions which exhibit a reversible gelation at body W0 96128057 2 1 ~ 0 2 5 5 ~
ttlll,u~ Lulc (32-37C) and/or at physiological pH (ca. pH 7.0-7.5) are particularly preferred for certain medical and pl~ uL;~dl uses. Responsive polymer network c u...~o~;~;u..~ which exhibit a reversible gelOEion at 70C or above are particularly preferred for oil field applications. Yet it is within the scope of the present 5 invention for reversible gelation to occur at much higher or lower L~u~ ulc:, or pHs or in response to other stimuli.
The responsive ~u...,uu~....L of the present invention may be any polymer which forms aggregates as a func~ion of tclll,u...tLulc. The responsive """1'" ~
typically possess regions of l~ydluLIl~ob;c and hydrophilic character. The responsive ~u.. ,uu.. ~ may be linear or branched. As will be apparent to one skilled in the art, a nonionic surfactant, due to its llydlu~hul/;c and hydrophilic character, may be suitable for use in the invention.
Suitable responsive l.,Ulll,UU11~ 7 include polyoxyalkylene polymers, such as block copolymers of different oxyalkylene units. At least one polyoxyalkylene unit 15 should have hydrophobic ~ ics and at least one polyoxyalkylene unit should have hydrophilic ~lldl .I~Cl ;~L;.S. A block copolymer of poly UAy c~lly l~le and polyu~y~uluyl~lle may be used in a preferred Clllbo~ of the invention.
Anothersuitableresponsive~u..l~ull..lLincludesPlulu.~ L~;~lockpolyolpolymers (BASF) having the general formula (POE)c(POP)d(POE)C, where POP is 20 poly u~ u~y lene and represents the lly d. upho~;c portion of the polymer and POE
is polyu~yc~llyl~.le and represents the hydrophilic portion of the polymer.
Pluronic~ Q~ASF) triblock polymers are ~ullll..~.~;dlly available for a in the range of 16 to 48 and b ranging from 54-62. Other exemplary polyoxyalkylene polymers include alkyl polyols, which are a product of alcohol . ~ nl. ..~ l reactions with 25 a lerminal alkyl or arylalkyl group. The alkyl group should have hydrophobic character, such as butyl, hexyl and the like. An alkyl polyol may have the general formula R-(OCH2CHj3nOH, where R is a nonpolar pendant group such as alkyl and arylalkyl and the like, and n is in the range of 5-1000. A preferred alkylpolyol is polyethyleneglycol mono(nollyl~,h..lyl)ether. Still other exemplary responsive ~u.. ,uu.. L~ may include cellulosic, cellulose ethers and guar gums which possess hydrophobic and hydrophilic regions along the polymer backbone which permit WO 96/28057 2 1 ~ 0 2 ~i 5 r~
bbl~b~Liull behavior. One or more responsive ~.,,,.I.~.l.. .,I~ may be used in the reSponsive polymer network composition of the present invention.
Another type of structural ~ulll,uollc.lL~ is an ionizable polymer. These materials typically are responsive to changes in pH and/or ionic strength. The 5 ionizable polymers of the present invention include linear, branched and/or crosslinked polymers. Of particular interest are carboxyvinyl polymers of monomers such as acrylic acid, methacrylic acid, ethacrylic acid, phenyl acrylic acid, pentenoic acid and the like. Polyacrylic acid is a preferred ~dlhul~yv;llyl polymer.
One or more pOly( d.l,u~yvillyl) polymers may be used in the responsive polymer 10 network r~mro-;tionc of the present invention. Acrylamides or 5~h~r;t~lrP~I
a.lyld,ll;d~ are also preferred l~mhn~limrntC Copolymers, such as by way of example only, copolymers of acrylic acid and methacrylic acid, are also ..."1~ .,.l.!~.~fl Naturally occurring polymers such as chitosan or hyaluronic acids are also possible as structural polymers since they are capable of forming an ionized 15 network as polymers or copolymers of other structural polymers.
As is dear from the rl~i~rirtir~n of the invention and from the Examples set forth below, covalent cross-linking of either or both of the ~onctitll.-nt polymers of the responsive polymer network is not required in order to observe gelation at low solids contents, such as less than 20 wt% or preferably less than about 10 wt%, or0 more preferably less than about 5 wt% or most preferably less than about 2.5 wt%.
The reversibly gelling responsive polymer networks fr~mr~r;tit~nC of the present invention are highly stable and do not exhibit any phase separation uponstanding or upon repeated cycling between a liquid and a gel state. Samples havestood at room Ltlll,U..d~UI~ for more than three months without any noticeable 25 d~ul~lpo~;~ion, clouding, phase separation or .~6. ,.1 ~ of gelation properties.
This is in direct contrast to polymer blends and aqueous mixed polymer solutions, where phase stability and phase separation is a problem, pdlL;~ululy where the polymers are immiscible in one another.
The Lll.L;UII;II~ of a ~U~,UO1I~.IL as respûnsive or structural may be 30 dependent upon the specific ~ ;l ul..ll~ dl trigger being considered. For example, in the polyacrylate/EO/PO/EO system, when ttlll~.. d~UI e is the trigger, WO 96/28057 2 l 9 ~ 2 ~ 5 PCT/IIS96/03480 EO/PO/EO is the rQponsive ' ""'1'" ~l however at pH of 2-5~ the polyacrylate comron~nt is the responsive .~ p.,~
Exemplary of the dramatic increase in viscosity and of the gelation of the responsive polymer network aqueous compositions of the invention with a change r 5 in ~CIII~)d~UlC are the aqueous responsive polymer network rf,mr~citi~nC shownin Figure 12. Figure 12 is a graph of viscosity vs. ~lllp.l ~UIC for 1%, 2% and 3%
aqueous rQponsive polymer network compositions CUIII~ , a triblock polyol of the general formula (POP)(POE)(POP) and polyacrylic acid (1:1) hydrated and neutralized. The viscosity measurements were taken on a Brookfield v;a,ulll.~.l at a shear rate of 0.44 sec ~ at pH 7Ø All solutions had an initial viscosity of about 1080 cP and exhibited a dramatic increase in viscosity to gel point at about 35C.
Final viscosities were d~ ;llld~CIy 33~000 cP~ 100~000 cP and 155~000 cP for the1 wt%, 2 wt% and 3 wt% ~mr~ nC IC~ y. This reprQents viscosity increases of about 30-7 90- and 140-fold, IQI~..Li~.ly.
The propertiQ of the rQponsive polymer network gel ~I-mro~;rir~n may be modified by varying the components and/or the lln-lU~lU~UlC of the polymer network. For example, use of different polymerization initiators in the formation of the . . " ,~l ;l, .,l structural ~ulll~!ull~llL of the responsive polymer network gel was found to decrease the tcl~lp~.dLulc for onset of viscosity by 5C. Also, different responsive ~UIIIpOII.II~ have been found to exhibit different reversible gelation ~el~ ulQ. In addition, ~ICpdl~iOIl of a responsive polymer network in a 0.5 M NaCI solution (as compared to distilled water) will result in a 10C decrease in the tClllp~ UlC of gelation. Thus, the ionic strength of the aqueous solution may be used to modify the properties of the ~u",~
Although not intended to be bound to a particular mode of oFeration, it is believed that several factors contribute to this unique and previously ul~le~ol~cl stability of responsive polymer networks. The polyoxyalkylene chains such as those of triblock polyol polymers are known to be s~ ct~nti~lly unfolded and free-flowing at ~clllp~ld~u~e~ below a critical ~CIll~.ld~UlC of gelling. Above this ttlll~ld~UlC, the polyoxyalkylene chains have been d~lllull~LId~cd to form agglomerations due to the tcl.l~ld~ulc-dependent association of the hydrophobic ~UIIIpUII.Il~ of the polymer. See, Atwood et al. Intl. ~. Ph~;rrn. 26:25-333 (1985)~

21 90255 ~
herein ill~o-~Juld~ed by reference. The polymer chàuns fold in on themselves dueto hydrophobic ;llLcld~iulla between llydlu~llùbic chain blocks. The polymer morphology of the structural polymer may be branched, creating the ..,~ ..,... rwith the responsive ~ which provides the stability of the polymer 5 network. Adachi et aL, which is i~ul~oldLe~ herein by reference, report that the polymeri_ation of acrylic acid in the presence of polyu~y~lllyl.lle resulted in arl interpolymer network having a ladder-like structure in which each oxyethylene residue forms a hydrogen bond with an acrylic acid residue. Template-formed polyacrylic acids of this type may contribute to the bonding observed in these new lû responsive polymer networks.
Figure 13 shows Pnrlr,th~-rmc of (a) 1% Pluronic~ F127 and (b) 1% responsive polymer network (Pluronic= F127/polyacrylic acid 1:1) obtained using a I~CS
Differential Scanning Calorimetry System (Microcal, Inc.) by heating samples with the rate of 15 centigrade/hour. Pluronic~ F127 is a triblock polymer made up of 15 ethylene oxide (EO) and propylene oxide (PO) blocks and having the general formula ~EO)(PO)(EO), where 70 wt% of the polymer is EO. Broad or sharp uLll..lllic peaks are seen at rh~t?rt"riCtir Ltllllu~ld~ulr of 29~ C which coincides with the onset of gelation in the responsive polymer network r~amr~citirm (see, F;g.
1). The peaks are measured to have enthalpy value of 1.26 cal/g. This enthalpy falls 20 within the range reported for Pluronic solutions (see, for instance, Wanka et a~, Colloid~rPolymer Scier~ce, 1990, 268, 101, herein ill~ul~uldLel by reference).
The aforrm~ntif~n~ thermal behavior of responsive polymer networks suggests that the observed increase of viscosity at around 30~ C is due to aggregation of triblock polyol molecules at this ~tl.l~.ldLu.r~ which, because of physical 25 ,l~"~l ". l and/orhydrogenbondingand/ortemplateformationwithpolyacrylic acid or polyacrylate molecules, serve as temporary cross-links in viscous gel-like structures of interactive polymer networks. Thus, nonionic surfactants should bewell suited to the responsive polymer network ~ of the present invention because of their aggregate- and micelle-forming r~r~hiliti~c in water.A general method of making the responsive polymer network Culll~ua;~iOllS
of the present invention comprises crlllhili7~tit~n of the responsive --...~ ina monomer capable of forming a structural ~ )ll ..l or formation of a melt of WO 961~8057 2 1 9 ~ 2 5 ~
the ~ r~ materials. Structural ~o~ .o~ suitable for use in the method are those which exhibit expansion and contraction in response to a change in ionic strength. The monomer is polymerized to the structural ~
Polymerization may be A-- 1.1.11~1;`1~``.~ by addition of a l~ulylll..~;ul~ initiator or 5 by irradiation ~rhni~ .oc The initiator may be a free radical initiator, such as chemical free radical initiators and uv or gamma radiation initiators. Conventional free radical initiators may be used according to the invention, including, but in no way limited to Al~ persulfate, benzoin ethyl ether, 1,2'-azobis(2,4-yl~..lLdll;~;le) (Vazo 52) and azol~ obu~ylu~ ;le (AIBN). Initiation may10 also be ~rrnmplich~Ad using cationic or ionic initiators. Many variations of this methods will be apparent to one skilled in the art and are rnntl~nnrl~tAd as within the scope of the invention. For example, the responsive uul~l~on~ may be dissolved in a monomer/water mixture instead of pure monomer. This may be particularly useful in instances where the tt~ ..diUl~-sensitive ..~ lg 15 monomer does not solubilize well in the monomer or in instances where the monomer of the structural UU111~7UII..I~ is a solid. It may be desirable to remove unreacted monomer from the resultant responsive polymer network. This may be rnmrlicbr~l using conventional ~rrhniTlAc such as, by way of example, dialysis.
Reverse phase polymerization may be used to prepare responsive polymer 20 network beads by dispersion of the responsive ~c,llll,oll~ /ionizable monomermixture in a nonpolar solvent such as heptane. The ~ , polymer/monomer solution is dispersed with agitation in a nonpolar solvent, such as heptane or hexane, in order to suspend droplets of the solution. Polymerization of the monomer is initiated by conventional means (i.e., addition of a initiator or 25 irradiation) in order to polymerize the monomer and form responsive polymer network beads. See, U.S.S.N. OS/276,532 filed July 18, 1995 and entitled "UsefulResponsive Polymer Gel Beads" for further ;.,r~.,.,..l ~.n on the preparation ofpolymer gel beads, herein ;II~UI~Old~Cl by reference. Such a method may be ;I,UIdlly desirable to provide a heat sink for the heat generated in the . . .l l ,. . ", ;.
30 poly.,l..;~;u,l reaction.

WO 96/2~0~7 2 1 9 0 2 5 5 1 ~I/IJ,.,S.'?~
Poly(ethylene oxide)-poly(,ululuyl.l~e oxide)-poly(ethylene oxide) triblock copolym~rs (trade name Pluronics, Poloxamers) in aqueous solutions show similar reverse t~ llUV;~ ;r; ~ properties at much higher solids content.
As an aqueous Pluronic solution is heated up, the ttlll~..d~Ulc exceeds a 5 certain value, called here the lower transition Ltlll,u.ldLulc, the viscosity changes by several orders of m~nitlld~ The ~u~ L~ of the solution changes from that of a liquid to that of a solid gel (like butter). The particular concentration needed to achieve such a transition depends on the kind of Pluronic polymer. For example, Pluronic FlD will not show the gelation properties at ~u~ Lions lower than 10 about 16%, whereas other Pluronics may need an even higher ronn~nrr~ti~)n Figure 14 illustrates the v;~ ~;r; ~ of 17% aqueous solution of Pluronic FlD. It also shows that the viscosity can be increased by adding a thickener, in this case 1% of 11~1. u~ y c~lly lcellulose Another potentially desirable property of a Pluronic solution is that when 15 the gel L~ ldLul~ is further increased, it can revert to a liquid state. This is useful, for example, in r~nn~ rtif~n with ~vllrul~l~dblc products, where there is a need to ~ tin~ich between the effect of contact with human body Itu~ u~c~, when the materials should be a gel, and a potentially higher ambient Lt.l.,u.ldlu.c (e.g, in a car trunk on a hot day), when the material should be a liquid Figure 15 shows this effect for a 17% solution of Pluronic F127, both for increasing and for decreasing L~ dLulc.
For may potential uses of the material it is desirable to be able to control theexact transition Lc~l~u..dLulc This can be achieved by varying the Pluronic type, as well as the ~ull~CU~ld~;Un of a given Pluronic solution. A ~ rul Wdl.l way 25 of controlling the ~cll~dLu.c is by modifying a solution of given concentration through ;-~u-,uo~lLion of additives, such as salts and polymers. Figure 16 shows the effect of addition of sodium chloride to a 30% solution of Pluronic F6rj. The transition L~,u~ Lulc can be brought down from 45C to 10C by addition of 10% ~by weight) of NaCI.
Suitable bladder materials may consist of a mono or .l.ulL;ld~lcd sealable structure of sufficient MVTR (Moisture Vapor Transmission Rate) to ensure produa E~ rO, ,~ over the lifetime of the product. Some examples include, but WO 96/28v57 2 1 9 2 r are not limited to, hydrocarbon based films, modified hydrocarbon based films, multi layered or composite films with both l~ rJll and metallic based layers.
Additionally, materials such as foams and the like may be adhered to the film for the purpose of making a more efficient (i.e. stronger) material after the 5 phase transition. Films may be sealabie using heat/pressure, sonic welding, h~ F and pressure adhesive sealing tPrhniq~l~ c Additionally, vacuum and heat forming of the package may be required.
The bladder may be ",~.,. r~ cl using one of three basic t~hniqll~c 1) form, fill and seal, and 2) vacuum form, fill and seal, and 3) pouch plcLbri~L;~-l, 10 fill and seal. Form, fill and seal utilizes the formation of the pouch while at the same time the pouch is filled with the responsive polymer network material.
Vacuum form, fill and seal utilizes a vacuum forming step prior to the filling and sealing operations. The bladder material must be somewhat thicker than the form fill and seal case in the material with thin out and weaken at the corners being 15 formed. The hollow that has been formed can be filled with a liquid, or a combination of liquids and solids in one or sequential steps.
Pouch p.c LI,I i~4Lion, fill and seal utilizes a premade pouch that is filled with liquids and/or solids in a sllhscT.~nr filling step and then sealed. Variations of this technique may include filling a premade rigid or soft pouch and then sealing or 20 filling a soft pouch utilizing one way valves that are ~ cut off and sealed.
Those skilled in the art will appreciate that the responsive polymer network and bladder containing apparatus of the present invention may be utilized for a wide variety of . . ", ~ and cushioning d~ ;UII~.
An increase in the material strength of the reversibly gelling polymers as 25 they change from a liquid to a gel is significant, but it may not be sufficient for some applications. An d~pl~ ri~L~ system may be designed to augment the strength. Figure 17(a) illustrates a cross-section of a bladder filled with a reversibly gelling polymer solution. As the material ~II..Ill~v;~ ;rles the bladder becomesharder. The resistance to flow in this design is not very great. It can be improved 30 by ;I.~ ol4~;on of a foam into the bladder, as illustrated in Figure 17(b) The foam is impregnated with the reversibly gelling polymer solution and provides a resistance to flow. When the material ~ us;L..~ the resistance becomes W0 96/280~7 2 1 9 0 2 5 5 1 ~ , 6N`7:
much greater, and the foam becomes very hard and rigid. Another structural design improving the strength of the viscosified matenal is presented irl Figure 17(c). The bladder is divided into a number of chambers (two are depiaed here) separated byrlarrow channels, through which the solution must flow in order to l~LI;:.Ll;I,uLc 5 itself when pressed or squeezed. When the solution viscosifies, the resistance to flow offered by these narrow channels is much greater than that in the case of an open bladder, as in Figure 17(a). Therefore the overall stiffness of the systems is enhanced.
Because the materials seleaed for the bladder have a ,... ~.., ..l .Ir F~rm.~ lhiliry to transport of water, P~ ;LUI~IY over the expeaed 2 year minimum lifetime of shoes, it is essential that the system not be one which is sensitive to the pected level of loss of water, which is estimated at a minimum of lOYo of the total water.
The design rules for this system then call for a material and material LonLcu~lr~;on which:
1) Display a gelation at the desired Ltul~ ulc.
2) Continues to display the gelation within the desired ~ .a~ulc range even after loss of nominally 10% fluid (or whatever loss of fluid is designed for the particular system) resulting in the Pluronic (poloxomer) being more LUlILCIl~ CLI
3) Is fluid at a ~CIIl~U~ UIC as low as possible, but at least -5 degrees C.

4) Display the necessary mrrh ~nir~l integrity for the application.
As an ample, using the charts "Aqueous Gel Ch..l~LL~ ;L~ of Pluronic and Tetronic Surfaaants" shown in Figures 18-28. If one would select Pluronic FlD as the solid and would desire a transition at 25 degrees, then the irlitial25 LUllLCllL~..Lion would be 18% solids. After the material loses 10% of the fluid, the becomes 20% solids. According to the chart, the transition temperature would be 22 degrees. If the sensitivity of the application to ~ellll~.d~ulc is not great, this may be satisfaaory. On the other hand, if the serlsitivity is high, this material may not be acceptable for the particular use.
30 Another example would be the use of Pluronic F68 as the solid. This material would need to be present at a level of 55% to be suitable. If this material lost 10%
of its water, then the solids LUllLC.l~ LiOn would be 57% which would then have WO 96/28057 2 1 9 0 2 5 5 . ~ " ~ ~ 71 q transition C~ u~.d.UlC of 22 degrees. Yet another example would be the use ofPluronic P103 which would need to be in the range of 34% ~ull~cllLld~;on to showa trqnsition of 25 degrees. If this material lost 10% of its water, resulting in a ~ull~cllLld~;Oll of 36%, the trqnsition tcll~ dLul~ would drop to 20 degrees, which S is also a very sizeable shift in gelation Lc~ dLulc and so a much less suitable materiqls choice.
On the other hand, if one would use Pluronic P105 as the solid the initial ~ull.cllLI d~;on would be in the range of 30%. If this material loses 10% of its water, the c un~cll~ld~;ol~ of solids wouldl be in the 32% range. This material hqs a chqnge 10 in transition ~elll~,d~ulc of 24 degrees C, so the shift is very small.
In order to further enhance the usefulness of the cllv;lul~ lly responsive gels and the thermally reversible polymer gels to its applicqtion in footweqr, athermochromatic dye can be ;II~UI~Old~C~ into the solution and/or the blqdder orcontqiner. The user's perception of a radical change in the material properties is then enhanced by a change in the material's color.
Exemplary conformable produa applications of the invention include, but are in no way limited to, footwear, such as golf shoes, ski boots, ice skates, in-line skates, roller skates, running shoes, cross-training shoes, volleyball shoes, bqsketball shoes, tennis shoes, football cleats, bqseball cleats, soccer cleats, lacrosse cleats, rugby shoes, field hockey; .lluu~ll,u;~.c~, helmets, headgear (i.e., wrestling), specialty gloves (i.e., baseball, boxing, biking, golf, lacrosse, equestrian, hockey, etc.), masks (i.e., hockey, lacrosse, baseball catcher, etc.), qnd lacrosse head stops.
Based on these principles, the user can selea the correa poloxomer to meet the ICU,U;~CIII~I~ of the arplif~tinn The reversibly gelling polymer network complexes and aqueous gels of the present invention may be .Inf!, ~rnn~ with reference to the following examples, which are provided for the pulposes of illustration and which are in not way limiting of the invention.
Exqm~le 1 This example describes the synthesis of a responsive polymer network and an aqueous responsive polymer network solution prepared using a triblock polymer of ethylene oxide and propylene oxide (Pluronic~ F27) and W0 96/280s7 r~

poly(acrylic acid). This example also ~IIldCL~J the gelation and the physical properties of the resultant responsive polymer network.
~h~, Block copolymer of propylene oxide (PO) and ethylene oxide (EO) having sandwich struaure (EO)A(PO)B(EO),~ (Pluronic F127 NF, Poloxamer 407 NF, where l'F" means Flakes, al2" means 12X300 3600 - MW of the poly(~lù,uyl~lle oxide) seaion of the block copolymer, a7~ ethylene oxide in the copolymer is 70 wt%, and nominal molecular weight is 12,600) from BASF (3.0 g) was dissolved in 3.0 g acrylic acid (Aldrich). This represents a s~hsr~nti~ly 1:1 molar ratio of Pluronic~: F127 and polyacrylic acid. The solution was deaerated by Ni bubbling for 0.5 h and following addition of 100 ~1 of freshly prepared saturated solution of A 11.1 ~ 1 persulfate (Kodak) in deionized water was kept at 70 C for 16 h rcsulting in a Lr~ c.l~ polymer.
vicrn~;ty ~ A known amount of the resukant polymer was suspended in 100 ml deionized water into which NaOH was added. Following 15 swelling for 3 days while stirring, the pH of the resulting fine scr~n on wasadjusted to 7. Samples of 15 ml each were taken, and pH in each vial was adjusted to desired value by addition of 1 M HCI or NaOH. Samples were then kept overnight and their viscosities were measured at different LCIU~ LUIC~ using Brookfield viscometer using either an SC4-18 or an SC4-25 spindle.
A control C~J.I ;III.IIL was done with a physical blend of Pluronic~ F127 and polyacrylic acid (MW 450,000) available *om Aldrich. Plurorlic~ F127 and polyacrylic acid were dissolved together in deionized water at 1 wt% total polymer ~u~l~cllLIaLiOn and the resultant solution was adjusted to pH 7, stirred and kept in I~L;~ IaLul. The IC~UII~ of the responsive polymer network c~-nnr~.C;~i~.n and the physical blend to LCIII~ LUI~ and pH is illustrated in Figs. 1, Z and 5.Figs. 1 and 2 clearly 1 ,.,."~ that the synthetic route outlined above resulted in a responsive polymer network polymeric system that is sensitive to pH and l..Lul~ of the CIlV;lulll~l.ll~. Note that the liquid-gel transition is very sharp, occurring over a very small LCIII~ LLUI~ change or ~pH. Fig. 5 is a viscosity vs.
30 tCIII~ LUIC graph comparing the gelling ~ U~L~ of the responsive polymer ne~work . I'~ and ~he phycic~l blend The b~tnd prep~red by phy~ically WO 96/28057 2 ~ 2 5 5 r~ 7 miYing of the triblock EO/PO/EO polymer and polyacrylic acid did not exhibit v;~ ;ry;llg effect either as a function of Le~ ..dLulc or pH.
It was generally observed that 1-5 wt% responsive polymer network ,rJ ~ .r"~c made of Pluronic0 F127 and polyacrylic acid viscosify at Lelll~ Lulc~
of around 30- C and higher if pH is adjusted to 6 or higher. The gelling effect was observed in responsive polymer network ~ ";L;Oll5 standing 3 months or longer.
Repeated heating and cooling of responsive polymer network rr,mro~;tir,nc did not cause d~L~,.;l~ld~;l)l~ of the responsive polymer network or the gelling effect.Solutions of either Pluronic F127 or polyacrylic acid (1-5 w% in water, adjusted to pH 6 or higher) or physical blends of the two lacked the gelling effects found for responsive polymer network rrmrr,citionc FY~mnl~ 2. This example describes the synthesis of a responsive polymer network and an aqueous responsive polymer network rrmrrl-;tirn prepared using Pluronic~ F88 Prill and poly(acrylic acid). This example also ~lldld~ the gelation and the physical properties of the resultant responsive polymer network ' ""'1'''`'"'~'' Svnthesis. Block copolymer of propylene oxide (PO) and ethylene oxide OE) having sandwich structure OEO)A(PO)BOEO)A (Pluronic F88 Prill, where "F"
means Flakes, "8" means 8X300-2400 - MW of the poly(p~ le oxide) section of the block copolymer, "8" means 80 wt% ethylene oxide in the copolymer is 80%,and the nominal molecular wei~ht is 11,400, 3.0 g) was dissolved in 3.0 g acrylic acid (Aldrich). The solution was prepared as described above for Example 1.
viscosjty Ill~?UIClll..IL~. A responsive polymer network composition was prepared and studied as described in Example 1. responsive polymer network compositions of 1 wt% Pluronic0 F88 and polyacrylic acid (1:1) viscosified at Lelll~ dLulc~ of around 48C and higher at pH 7, as is illustrated in the viscosity vs. Lelll~.d~ulc graph of Figure 29. Repeated heating and cooling of responsive polymer network '"`l' ~ was not observed to cause d.L~.;o-dLkJIl of the gelation effect. This III.~UICIII.,.I~ correlates well with the observed Cll.lld~,L~ L;C
~c~u~.~dLulC of 47~ C of the rnt~r th~rmi~ peaks that are seen in the DSC rn~lnth.~rm The peaks are measured to have enthalpy value of 0.9 cal/g.

.

WO 96/28057 1 ~ 1/l).., ~.'^~ ' F~ ple 3. This example d~ o~ dLe~ the ability to shift the tc~ dLul~
at which an the polymer network gel viscosifies by addi~ion of a salt into the aqueous solution.
The interpenetrating polymer networl~ was prepared as described in Example

5 1. The dry polymer was placed into either deionized water or a 0.5 M NaCI
solution. in plu~olLiulls to provide a 2.5 wt% solution. Viscosity profiles for the two aqueous solutions were ~ ;.,.`;1 and are reported in Figure 30. The viscosity of a 2.5 wt% solution in deionized water has a higher initial viscosity than that in 1 0.5M NaCI solution at 20C. Further, the telll~.ldLulc at which gelation 10 occurs shifts from about 35 C in water to about 30 C in the NaCI solution. Thus, a change in the ionic strength of the aqueous gel cnmrr~itirn alters its gelling propertieS.
While it is apparent that the illustrative ~..,1.,..1;.,...,1 of the invention herein disclosed fulfills the objeaives stated above, it will be d~J~lC~;~Ltl that numerous 15 mr,rlifir~ti~.n and other cl~lbod;l~ L~ may be devised by those skilled in the art.
Therefore, it will be understood that the appended claims are intended to cover all such mnt~ifi~tir,n~ and cl..bod;~u~.lL~ which come within the spirit and scope of the present invention.
What is claimed is:

Claims (61)

1. A shoe that conforms to foot contours and provides cushioning comprising:
a shoe sole; and a shoe upper attached to the shoe sole, comprising an outer layer, an inner layer and a conforming layer therebetween, wherein a first portion of the conforming layer is comprised of viscoelastic gel and a second portion of the conforming layer is comprised of environmentally-responsive gel.

2. The shoe of claim 1, wherein the environmentally-responsive gel is a temperature-responsive gel that will react to the heat emanating from a foot inserted into the shoe to express a liquid.

3. The shoe of claim 2, wherein the temperature-responsive gel is a microporous, fast responsive, crosslinked gel obtainable from a polymeric precursor, the temperature-responsive gel being of sufficient flexibility to be reversibly responsive to a change in temperature.

4. The shoe of claim 3, wherein the temperature-responsive gel has lower critical solution temperatures in an aqueous solution and water-soluble crosslinkers.

5. The shoe of claim 3, wherein the precursor is a linear polymer.

6. The shoe of claim 3, wherein the precursor is a cellulose ether.

7. The shoe of claim 3, wherein the precursor is a hydroxypropyl acrylate/hydroxyethyl acrylate copolymer.

8. The shoe of claim 7, wherein the aqueous solution includes sucrose in the range of 30% to 60.

9. The shoe of claim 1, wherein the viscoelastic gel is a polyurethane gel that provides a viscoelastic medium that flows due to foot pressure and thereby provides a conforming fit and cushion to a foot inside the shoe.

10. The shoe of claim 9, wherein the polyurethane gel is not encapsulated within a bladder.

11. The shoe of claim 10, wherein the polyurethane gel is a soft elastomer with high sol fraction.

12. The shoe of claim 11, wherein the polyurethane gel is comprised of a high molecular weight triol.

13. The shoe of claim 12, wherein the high molecular weight triol has a molecular weight greater than 6000.

14. The shoe of claim 10, wherein the polyurethane gel is comprised of a diisocyanate.

15. The shoe of claim 1, wherein the viscoelastic gel is a butadiene style rubber that conforms to the foot and is not encapsulated within a bladder.

16. The shoe of claim 15, wherein the viscoelastic gel is comprised of an oil and polyisobutadiene.

17. The shoe of claim 15, wherein the viscoelastic gel is comprised of a styrene ethylene butadiene styrene triblock medium molecular weight rubber polymer and oil.

18. The shoe of claim 15, wherein the viscoelastic gel is further comprised of hollow microspheres.

19. The shoe of claim 15, wherein the polyurethane gel is further comprised of a blowing agent.

20. The shoe is claim 1, further including a third portion of the conforming layer which is comprised of a memory foam.

21. The shoe of claim 1, wherein the conforming layer first portion is comprised of a first viscoelastic gel portion configured and dimensioned to correspond to a foot heel.

22. The shoe of claim 21, wherein the conforming layer first portion further includes a plurality of viscoelastic gel finger sections extending from the first viscoelastic gel portion.

23. The shoe of claim 1, wherein the conforming layer first portion is configured and dimensioned to correspond to a top portion of a fore foot.

24. The shoe of claim 2, wherein the second portion is configured such that the temperature-responsive gel is secured within a bladder and is positioned in the shoe quarter such that it corresponds to a fore foot and that the liquid can flow through the bladder to correspond to a collar section of the shoe.

25. The shoe of claim 20, wherein the first portion of the conforming layer and the third portion of the conforming layer have different hardnesses.

26. The shoe of claim 25, wherein the first portion of the conforming layer has a -000 hardness of about 40 to 60 and the third portion of the conforming layer has a Shore C hardness of about 25.

27. A shoe foot bed comprising:
a foam pad for at least underlying a portion of a foot;

a relatively hard viscoelastic gel heel plug secured to the foam pad for underlying at least a portion of a foot heel; and a relatively soft, flowable viscoeleastic portion secured to the foam pad for underlying at least a foot arch.

28. The shoe foot bed of claim 27, wherein the relatively soft, flowable viscoelastic portion extends further includes a second flowable gel portion thatcorresponds to a foot heel.

29. The shoe foot bed of claim 27, wherein the relatively soft, flowable viscoelastic portion further includes a plurality of finger portions.

30. The shoe foot bed of claim 27, further including a metatarsal pad made of a relatively hard, viscoelastic gel for underlying a foot metatarsal.

31. The shoe foot bed of claim 27, further comprising at least one wing portion, wherein the wing portion is comprised of a temperature-responsive gel section.

32. The shoe foot bed of claim 27, further comprising at least one wing portion, wherein the wing portion is comprised of a relatively soft, flowable viscoelastic gel section.

33. A method of forming a shoe, comprising the steps of:
molding viscoelastic gel in a mold with a shoe inner layer to form a first portion of a conforming layer that is attached to the shoe inner layer;
placing a temperature-responsive gel and bladder containing the same into the conforming layer to form a second portion of the conforming layer; and attaching the shoe outer layer to the inner layer such that the conforming layer is between the inner layer and the outer layer.

34. A method of forming a shoe component comprising the steps of:

pouring viscoelastic gel and foam into a mold;
laying a fabric layer on top of the mold by attaching the fabric layer to a top plate of the mold;
closing the mold with the top plate;
heating the mold to form an integral conforming layer and fabric layer.

35. The method of forming the shoe component of claim 34, further comprising the step of attaching an outer layer to the integral conforming layer and fabric layer.

36. The method of forming the shoe component of claim 34, wherein the viscoelastic gel is poured into the mold and then the foam comprising polyurethane gel with microspheres is poured into the mold.

37. the method of forming the shoe component of claim 34, wherein heating the mold includes heating the mold top plate.

38. The method of forming the shoe component of claim 34, further comprising the steps of forming a temperature-responsive gel and bladder and adding the temperature-responsive gel and bladder to the integral conforming layer and fabric layer.

39. The method of forming the shoe component of claim 38, wherein the step of forming the temperature-responsive gel and bladder is comprised of the steps of:
placing a first layer of plastic film into a second mold;
vacuum forming the first layer of plastic film over the second mold;
placing the temperature-responsive gel material into the second mold on top of the first layer;
placing a second layer of plastic film over the mold; and bonding the first and second layers together.

40. A shoe that conforms to foot contours and provides cushioning comprising:
a shoe sole; and a shoe upper attached to the shoe sole, comprising an outer layer, an inner layer and a conforming layer therebetween, wherein a first portion of the conforming layer is comprised of viscoelastic gel and a second portion of the conforming layer is comprised of thermally reversibly gelling polymer.

41. The shoe of claim 40, wherein the thermally reversibly gelling polymer comprises:
responsive component capable of aggregation in response to a change in environmental stimulus and a structural component which supports and interacts with the responsive component.

42. The shoe of claim 40, wherein the thermally reversibly gelling polymer comprises a triblock polyol.

43. A system for providing thermally reversibly conformable mechanical support to the human foot comprising:
a thermally responsive polymer gel contained in a polymer membrane of limited water permeability and located within or in an article of footwear as a footbed, sockliner, or an integral bladder, said thermally responsive gel designed to be fluid below the expected use temperature (the temperature to which the gel/bladder system will normally be raised due to heat evolution by the foot) asmeasured at the point at which the gel is disposed and to increase viscosity or otherwise provide support when exposed to the expected use temperature as measured at the point at which the gel is disposed.

44. The system of claim 43 comprising:
a reversibly thermochromic material or other responsive chromic material.

45. The system of claim 43 wherein the viscosity of the gel below the expected use temperature is at or below the maximum useful flow viscosity and the viscosity of the gel above the expected use temperature is at or above the minimum useful support viscosity.

46. The system of claim 43 comprising a gel composite.

47. The system of claim 43 wherein the gel is part of a system designed to give orthotic or prosthetic support.

48. The system of claim 43 wherein the gel is part of a system designed to control motion of the foot, as in an ankle locking system for a ski boot or similar article.

49. The system of claim 43 wherein the gel expands or contracts to release or provide liquid at the expected use temperature.

50. The system of claim 43 wherein the gel contains solutes designed to change the thermal or viscosity properties of the gel.

51. The system of claim 43 wherein the gel contains an antifreeze designed to prevent freezing or boiling at naturally occurring conditions from -25°
F to +155° F

52. The system of claim 43 comprising:
a membrane designed to allow permeation of no more than one percent of the fluid over a two year period.

53. The system of claim 43 comprising:
a membrane designed to allow permeation of no more than one percent of the fluid over a six month period.

54. The system of claim 43 comprising:
a membrane designed to allow permeation of no more than one percent of the fluid over a one month period.

55. The system of claim 43 comprising:
a gel designed so that permeation of up to ten percent of the fluid will not change the thermal viscosification or properties.

56. The system of claim 43 comprising:
a factor of 3 increase in viscosity measured at .44 sec-1 from below the expected use temperature to above the expected use temperature.

57. The system of claim 43 comprising:
a factor 10 increase in viscosity measured at .44 sec-1 from below the expected use temperature to above the expected use temperature.

58. The system of claim 43 comprising:
a factor of 30 increase in viscosity measured at .44 sec-1 from below the expected use temperature to above the expected use temperature.

59. The system of claim 43 comprising:
a factor of 100 increase in viscosity measured at .44 sec-1 from below the expected use temperature to above the expected use temperature.

60. The system of claim 43 comprising:
a factor of 300 increase in viscosity measured at .44 sec-1 from below the expected use temperature to above the expected use temperature.

61. The system of claim 43 comprising:
a gel which has a maximum useful flow viscosity such that it can easily be injected or otherwise introduced into a bladder during the manufacturing process.