Absorbent article comprising a synthetic polymer derived from a renewable resource and methods of producing said article
An absorbent article is disclosed having a topsheet, a backsheet joined with the topsheet, an absorbent core disposed between the topsheet and the backsheet, and a synthetic superabsorbent polymer derived from a first renewable resource via at least one intermediate compound, wherein said superabsorbent polymer exhibits a defined Saline Flow Conductivity value and Absorption Against Pressure value. Alternately, an absorbent article is disclosed having a synthetic polyolefin derived from a first renewable resource via at least one intermediate compound. The synthetic polyolefin exhibits defined performance characteristics making the polyolefin particularly useful in certain components of the absorbent article. Methods for making the aforementioned absorbent articles are also disclosed.
1. A method for making a disposable absorbent article, the method comprising:
(a) deriving a sugar from a renewable resource;
(b) fermenting the sugar to yield lactic acid using a microorganism;
(c) dehydrating the lactic acid to provide acrylic acid;
(d) polymerizing the acrylic acid to form a synthetic superabsorbent polymer; and
(e) incorporating the synthetic superabsorbent polymer into the disposable absorbent article;
wherein the superabsorbent polymer has a 14 C/C ratio of about 1.0×10 −14 or greater and exhibits an Absorption Against Pressure (AAP) value of at least about 15 g saline per gram of superabsorbent polymer.
2. The method of claim 1 , wherein the acrylic acid is neutralized from about 50 mole % to about 95 mole %.
3. The method of claim 1 , wherein the superabsorbent polymer is formed using a homogenous solution polymerization process.
4. The method of claim 1 , wherein the superabsorbent polymer is formed using a multi-phase polymerization process.
5. The method of claim 4 , wherein the multi-phase polymerization process is selected from the group consisting of inverse emulsion processes and suspension polymerization processes.
6. The method of claim 1 , wherein the superabsorbent polymer is formed by polymerization in the presence of a di- or poly-functional monomer.
7. The method of claim 1 , further comprising surface-crosslinking the superabsorbent polymer.
8. The method of claim 1 , wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of at least about 20 g saline per gram of superabsorbent polymer.
9. The method of claim 8 , wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of from about 15 g to about 25 g saline per gram of superabsorbent polymer.
10. The method of claim 9 , wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of from about 17 g to about 23 g saline per gram of superabsorbent polymer.
11. The method of claim 9 , wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of from about 20 g to about 23 g saline per gram of superabsorbent polymer.
12. The method of claim 1 wherein the superabsorbent polymer exhibits a saline flow conductivity (SFC) of at least about 30×10 −7 cm 3 ·sec/g.
13. The method of claim 12 wherein the superabsorbent polymer exhibits a saline flow conductivity (SFC) of at least about 50×10 −7 cm 3 ·sec/g.
14. The method according to claim 1 wherein the superabsorbent polymer has a 14 C/C ratio of about 1.0×10 −13 or greater.
15. The method according to claim 14 wherein the superabsorbent polymer has a 14 C/C ratio of about 1.0×10 −12 or greater.
16. The method according to claim 14 wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of at least about 20 g saline per gram of superabsorbent polymer.
17. The method according to claim 1 wherein the disposable absorbent article comprises an absorbent core, wherein the absorbent core comprises no more than about 20%, by weight, of an absorbent fibrous material.
18. The method according to claim 17 wherein the superabsorbent polymer exhibits an Absorption Against Pressure (AAP) value of at least about 20 g saline per gram of superabsorbent polymer.