Bra incorporating shape memory polymers and method of manufacture thereof

1. A front panel for a sports bra comprising:

an interior liner layer having a back face configured to contact a wearer's skin, and having a size and shape configured to substantially cover the wearer's breasts;

an exterior shell layer having a back face facing a front face of the interior liner layer, having a size and shape configured to substantially cover the wearer's breasts, and coupled to the interior liner layer; and

a film layer located between the front face of the interior liner layer and the back face of the exterior shell layer, wherein the film layer comprises a thermally-induced shape memory polymer having viscoelastic properties when at body temperature of the wearer;

wherein, when the front panel is worn as part of a sports bra, the film layer stiffens as a frequency of movement of the wearer's breasts increases, thereby absorbing forces caused by the movement of the wearer's breasts, and wherein the thermally-induced shape memory polymer stiffens to absorb energy at frequencies of breast movement of between 1 Hz and 100 Hz and is capable of absorbing a force of up to 0.03 N.

2. The front panel of claim 1 , wherein the thermally-induced shape memory polymer is configured to stiffen to absorb between 0.015 N and 0.03 N of force at frequencies of breast movement of between 6 Hz and 15 Hz.

3. The front panel of claim 1 , wherein the film layer comprises a first breast cup and a second breast cup.

4. The front panel of claim 3 , wherein the film layer has a first aperture at an apex of the first breast cup and a second aperture at an apex of the second breast cup.

5. The front panel of claim 3 , wherein the first and second breast cups are molded to a concave shape.

6. The front panel of claim 1 , further comprising an internal fabric layer coupled between the back face of the exterior shell layer and a front face of the film layer.

7. The front panel of claim 1 , wherein the thermally-induced shape memory polymer is a polyurethane elastomer comprising a bifunctional diisocyanate, a bifunctional polyol and a bifunctional chain extender polymerized at a molar ratio of 2.00-1.10:1.00:1.00-0.10 using one of a pre-polymer method and a bulk method, and wherein the film layer has multiple apertures at an aperture ratio of ranging from 10 to 90%.

8. The front panel of claim 7 , wherein the film layer comprises a layer of fabric and a layer of the thermally-induced shape memory polymer coating at least one side of the layer of fabric.

9. The front panel of claim 7 , wherein a molecular weight of the bifunctional diisocyanate ranges from 174 to 303, a molecular weight of the bifunctional polyol ranges from 300 to 2,500, and the bifunctional chain extender is a diol or diamine with a molecular weight ranging from 60 to 360.

10. A front panel for a sports bra comprising:

an interior liner layer having a back face configured to contact a wearer's skin, and having a size and shape configured to substantially cover the wearer's breasts;

an exterior shell layer having a back face facing a front face of the interior liner layer, having a size and shape configured to substantially cover the wearer's breasts, and coupled to the interior liner layer; and

a film layer located between the front face of the interior liner layer and the back face of the exterior shell layer, wherein the film layer comprises a thermally-induced shape memory polymer having viscoelastic properties when at body temperature of the wearer;

wherein, when the front panel is worn as part of a sports bra, the film layer stiffens as a frequency of movement of the wearer's breasts increases, thereby absorbing forces caused by the movement of the wearer's breasts, and wherein the thermally-induced shape memory polymer stiffens to absorb energy at frequencies of breast movement of between 1 Hz and 100 Hz and is capable of absorbing a force of up to 0.03 N; and

wherein the thermally-induced shape memory polymer is a polyurethane elastomer comprising a bifunctional diisocyanate, a bifunctional polyol and a bifunctional chain extender polymerized at a molar ratio of 2.00-1.10:1.00:1.00-0.10 using one of a pre-polymer method and a bulk method, and wherein the film layer has multiple apertures at an aperture ratio of ranging from 10 to 90%.

11. The front panel of claim 10 , wherein the thermally-induced shape memory polymer is configured to stiffen to absorb between 0.015 N and 0.03 N of force at frequencies of breast movement of between 6 Hz and 15 Hz.

12. The front panel of claim 10 , wherein the film layer comprises a first breast cup and a second breast cup.

13. The front panel of claim 12 , wherein the film layer has a first aperture at an apex of the first breast cup and a second aperture at an apex of the second breast cup.

14. The front panel of claim 12 , wherein the first and second breast cups are molded to a concave shape.

15. The front panel of claim 10 , further comprising an internal fabric layer coupled between the back face of the exterior shell layer and a front face of the film layer.

16. The front panel of claim 10 , wherein the film layer comprises a layer of fabric and a layer of the thermally-induced shape memory polymer coating at least one side of the layer of fabric.

17. The front panel of claim 10 , wherein a molecular weight of the bifunctional diisocyanate ranges from 174 to 303, a molecular weight of the bifunctional polyol ranges from 300 to 2,500, and the bifunctional chain extender is a diol or diamine with a molecular weight ranging from 60 to 360.