Biodegradable Aliphatic-Aromatic Copolyester

• US 20080194770A1
• Filed: 03/17/2006
• Published: 08/14/2008
• Est. Priority Date: 03/18/2005
• Status: Active Grant

• Current Assignee: Novamont S.p.a.
• Original Assignee: Novamont S.p.a.
• Inventors: Bastioli, Catia, Floridi, Giovanni, Milizia, Tiziana, Cella, Giandomenico, Tosin, Maurizio, Lallaro, Andrea Scaffidi
• Granted Patent: US 8,193,300 B2
• Time in Patent Office: Days
• US Class Current: 525/411
• CPC Class Codes: C08G 63/16 Dicarboxylic acids and dihydroxy compounds
• CPC Class Codes: C08L 1/00 Compositions of cellulose, modified cellulose or cellulose derivatives
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 3/02 Starch; Degradation products thereof, e.g. dextrin
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: Y10T 428/1331 Single layer [continuous layer]
• CPC Class Codes: Y10T 428/1334 Nonself-supporting tubular film or bag [e.g., pouch, envelope, packet, etc.]
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/29 Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31786 Of polyester [e.g., alkyd, etc.]

Abstract

Biodegradable aliphatic/aromatic copolyester comprising 49 to 66 mol % of an aromatic polyfunctional acid; 51 to 34 mol % of an aliphatic acid, at least 70% of which is sebacic acid; and butandiol; and blends containing such copolyester.

Claims

1-15. -15. (canceled)

16. A biodegradable aliphatic/aromatic copolyester (AAPE) comprising:

A) an acid component comprising repeating units of;

1) 49 to 66 mol % of an aromatic polyfunctional acide;

2) 51 to 34% % of an aliphatic acid, at least 70% of which, is sebacic acide;

B) butandiol;

said AAPE being biodegradable according to the Standard ISO 14855 Amendment 1 of more than 40% in 30 days, with respect to cellulose used as reference, and having;

a density of less than 1.22 g/cc;

a number average molecular weight M_n of 40,000 to 140,000;

an inherent viscosity of 0.8 to 1.5;

a polydispersity index M_w/M_n of between 1.8 and 2.5.

17. A biodegradable polyester according to claim 16, characterized in that said acid component comprises 49.5 to 63 mol % of an aromatic polyfunctional acid (A1);

and 50.5 to 37% of an aliphatic acid (A2), at least 70% of which is sebacic acid.

18. A biodegradable polyester according to claim 16, characterized in that said acid component comprises 50 to 61 mol % of an aromatic polyfunctional acid (A1);

and 50 to 39% of an aliphatic acid (A2), at least 70% of which is sebacic acid.

19. A biodegradable polyester according to claim 16, characterized in that said aliphatic acid A2 comprises at least 90% of sebacic acid.

20. A biodegradable polyester according to claim 16, characterized in that said biodegradability is more than 60%.

21. A biodegradable polyester according to claim 16, characterized in that said density is less than 1.21 g/cc.

22. A biodegradable polyester according to claim 16, characterized in that said density is less than 1.20 g/cc.

23. A biodegradable polyester according to claim 16, characterized in that the aliphatic acid A2 comprises at least one hydroxyl acid or one dicarboxylic acid different from sabacic acid, in an amount of up to 30% mol with respect to the total molar content of sabcic acid.

24. A biodegradable polyester according to claim 23, characterized in that the aliphatic acid A2 comprises at least one hydroxyl acid or one dicarboxylic acid different from sebacic acid, in an amount of up to 10% mol with respect to the total molar content of sebacic acid.

25. A biodegradable polyester according to claim 16, in which the aromatic polycarboxylic acid is a compound of the phthalic-acid type, preferably terephthalic acid.

26. A biodegradable polyester according to claim 16, characterized by being rapidly crystallizable and by having a crystallization temperature T_c higher than 30°

C.

27. A biodegradable polyester according to claim 26, characterized by being rapidly crystallizable and by having a crystallization temperature T_c higher than 40°

C.

28. A polyester according to claim 16, characterized by an energy at break higher than 80 MJ/M².

29. A polyester according to claim 28, characterized by an energy at break higher than 100 MJ/m².

30. A polyester according to claim 16, characterized by a Elmendorf tear strength higher than 20 N/mm in the longitudinal direction, and higher than 0 N/mm for the quantity:

(cross direction+longtitudinal direction)/2.

31. A polyester according to claim 30, characterized by an Elmendorf tear strength higher than 25 N/mm in the longitudinal direction, and higher than 65 N/mm, for the quantity:

(cross direction+longitudinal direction)/2.

32. A polyester according to claim 16, used in blends, obtained also by means of reactive extrusion, both with polyesters of the same type and with other biodegradable polymers whether of natural origin or of synthetic origin.

33. The blends of biodegradable polyesters according to claim 32, characterized in that the polymers of synthetic origin are selected from the group consisting of polylactic acid, poly--caprolactone, polyhydroxybutyrates, such as polyhydroxybutyrate-valerate, polyhydroxybutyrate porpanoate, polyhydroxybutyrate-hexanoate, polyhydroxybutyrate-decanoate, polyhydroxybutyrate-dodecanoate, polyhydroxybutyrate-hexadecanoate, polyhydroxybutyrate-octadecanoate, and polyalkylene succiantes.

34. The blends of biodegradable polyesters according to claim 32, characterized in that the polymers of natural origin are starch, cellulose, chitosan, alginates or natural rubbers.

35. The blends of biodegradable polyesters according to claim 34, characterized in that the starches and celluloses are modified, such as starch or cellulose esters with a degree of substitution of between 0.2 and 2.5, hydroxypropylated starches, and modified starches with fatty chains.

36. The blends of biodegradable polyesters according to claim 34, characterized in that the starch is present in the destructed or galetinized form or in the form of fillers.

37. The blends of biodegradable polyesters according to claim 34, in which the polymer of synthetic origin is polylactic and the polymer of natural origin is starch.

38. Use of the polymer according to claim 16 for the production of:

films, whether one-directional or two-directional films, and multilayer films with other polymeric materials;

films for use in the agricultural sector as mulching films;

bags and sheathes for gathering organic matter;

packaging for foodstuffs both single-layer and multilayer, such as for example containers for mile, yoghurt, meat, beverages, etc.;

coating obtained with the extrusion-coating technique;

multilayer laminates with layers of paper, plastic material, aluminum, metallized films;

foamed for foamable beads for the production of pieces formed by sintering;

foamed and semi-foamed products including foamed blocks made up of pre-foamed particles;

foamed sheets, thermoformed sheets and containers obtained therefrom for the packaging of foodstuff;

containers in general for fruit and vegetables;

composites with gelatinized, destructured and/or complexed starch, natural starch, flours, other fillers of natural, vegetal or inorganic origin;

fibres, fabrics and non-woven fabrics for the sector of health, sanitary products, and hygiene.