Biodegradable Aliphatic-Aromatic Polyesters

• US 20080214702A1
• Filed: 03/17/2006
• Published: 09/04/2008
• Est. Priority Date: 03/18/2005
• Status: Active Grant

• Current Assignee: Novamont S.p.a.
• Original Assignee: Novamont S.p.a.
• Inventors: Cella, Gian Domenico, Bastioli, Catia, Floridi, Giovanni, Milizia, Tiziana, Lallaro, Andrea Scaffidi, Tosin, Maurizio
• Granted Patent: US 8,193,298 B2
• Time in Patent Office: Days
• US Class Current: 524/35
• 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 50 to 60 mol % of an aromatic dicarboxylic acid and 40 to 50 mol % of an aliphatic acid, at least 90% of which is a long-chain dicarboxylic acid (LCDA) of natural origin selected from azelaic acid, sebacic acid, brassylic acid or mixtures thereof; and a diol component.

Claims

1. Biodegradable aliphatic/aromatic copolyester (AAPE) comprising:

A) an acid component comprising repeating units of;

1) 50 to 60 mol % of an aromatic polyfunctional acid;

2) 40 to 50 mol % of an aliphatic acid, at least 90% of which is a long-chain dicarboxylic acid (LCDA) of natural origin selected from azelaic acid, sebacic acid, brassylic acid or mixtures thereof;

B) at least one diol component;

said aliphatic long-chain dicarboxylic acid (LCDA) and said diol component (B) having a number of carbon atoms according to the following formula;

(C_LCDA·

y_LCDA)/2+C_B·

y_B>

7.5

where;

C_LCDA is the number of carbon atoms of the LCDA and can be 9, 10 or 13;

y_LCDA is the molar fraction of each LCDA on the total number of moles of LCDA;

C_B is the number of carbon atoms of each diol component;

y_B is the molar fraction of each diol on the total number of moles of the diol component (B) said AAPE having;

a biodegradability after 90 days higher than 70%, with respect to pure cellulose according to the Standard ISO 14855

Amendment 1, —

a density of equal to or less than 1.2 g/cc;

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

an inherent viscosity of 0.8-1.5.

2. Biodegradable polyester according to claim 1, characterized in that said aromatic dicarboxylic acid is selected from the group consisting of the phthalic acids.

3. Bioedgradable polyester according to claim 2, characterized in that said aromatic dicarboxylic acid is terephthalic acid.

4. Biodegradable polyester according to claim 1, characterized in that the polydispersity index M_w/M_n is between 1.7 and 2.6.

5. Biodegradable polyester according to claim 4, characterized in that said polydispersity index M_w/M_n is between 1.8 and 2.5.

6. Biodegradable polyester according to claim 1, characterized in that said diol is selected from the group consisting of:

1,2-ethandiol, 1,2-propandiol, 1,3-propandiol, 1,4-butandiol, 1,5-pentandiol, 1,6-hexandiol, 1,7-heptandiol, 1,8-octandiol, 1,9-nonandiol, 1,10-decandiol, 1,11-undecandiol, 1,12-dodecandiol, 1,13-tridecandiol, 1,4-cyclohexandimethanol, propylene glycol, neo-pentyl glycol, 2-methyl-1,3-propandiol, dianhydrosorbitol, dianhydromannitol, dianhydroiditol, cyclohexandiol, and cyclohexanmethandiol.

7. Biodegradable polyester according to claim 6, characterized in that said diol has from 2 to 10 carbon atoms.

8. Biodegradable polyester according to claim 7, characterized in that said diol has from 2 to 4 carbon atoms.

9. Biodegradable polyester according to claim 1, characterized in that said aliphatic long-chain dicarboxylic acid (LCDA) and said diol component (B) have a number of carbon atoms according to the following formula:

(C_LCDA·

Y_LCDA/2)+C_B·

y_B>

8

10. Biodegradable polyester according to claim 1, characterized in that said biodegradability after 90 days is higher than 80%.

11. Biodegradable polyester according to claim 1, characterized by a crystallization temperature T_c higher than 25°

C.

12. Biodegradable polyester according to claim 11, characterized by a crystallization temperature T_c higher than 30°

C.

13. Biodegradable polyester according to claim 12, characterized by a crystallization temperature T_c higher than 40°

C.

14. Biodegradable polyester according to claim 1, characterized in that said aliphatic acid comprises at least one hydroxy acid in an amount of up to 10 mol % with respect to the total molar content of the aliphatic acid.

15. Biodegradable polyester according to claim 1, characterized by being a component of a blend both with polyesters of the same type and with other biodegradable polymers of natural origin or of synthetic origin.

16. Biodegradable polyester according to claim 15, obtained by reactive extrusion.

17. Blend of biodegradable polyesters according to claim 15, characterized in that the polymer of synthetic origin is selected from the group consisting of polylactic acid, poly-e-caprolactone, polyhydroxybutyrates, such as polyhydroxybutyrate-valerate, polyhydroxybutyrate propanoate, polyhydroxybutyrate-hexanoate, polyhydroxybutyrate-decanoate, polyhydroxybutyrate-dodecanoate, polyhydroxybutyrate-hexadecanoate, polyhydroxybutyrate-octadecanoate, and polyalkylene succinates.

18. Blend of biodegradable polyesters according to claim 15, characterized in that the polymers of natural origin are selected from the group consisting of starch, cellulose, chitosan, alginates or natural rubbers.

19. Blend of biodegradable polyesters according to claim 18, characterized in that said starch or cellulose is modified.

20. Blend of biodegradable polyesters according to claim 19, characterized in that the modified starch or celluloses are starch or cellulose esters with a degree of substitution of between 0.2 and 2.5, hydroxypropylated starches, and modified starches with fatty chains.

21. Blend of biodegradable polyesters according to claim 18, characterized in that the starch is present in a destructurized or gelatinized form or in the form of fillers.

22. Blend of biodegradable polyesters according to claim 15, in which the polymer of synthetic origin is polylactic and the polymer of natural origin is starch.

23. Use of the polyesters according to claim 1 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 milk, yoghurt, meat, beverages, —

coatings obtained with the extrusion-coating technique;

-multilayer laminates with layers of paper, plastic materials, aluminium, metallized films, —

foamed or 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 foodstuffs;

-containers in general for fruit and vegetables;

composites with gelatinized, destructurized 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.