DEGRADABLE PACKAGING FILM FOR FRUIT AND VEGETABLES

Abstract

The present invention relates to a degradable film for packaging fruit and vegetables, which comprises a polyolefin-based polymer matrix that incorporates an antimicrobial (biocidal or fungicidal) active ingredient of an essential oil, selected from the group consisting of: carvacrol, cinnamaldehyde, cineol, sabinene, thujaplicin, or a mixture of same, or incorporates the essential oil itself, selected from the group consisting of: cinnamon oil, oregano oil, eucalyptus oil, nutmeg oil, hinoki oil, or a mixture of same. The polymer matrix further comprises degrading agents. The invention also relates to a method for microencapsulating the antifungal or antibacterial active ingredients of the essential oil or the essential oil itself, and to a method for preparing the film.

Claims

1. Degradable film for packaging of fruits and vegetables with antimicrobial properties, comprising a polyolefin-based polymer matrix incorporating an active antimicrobial agent of essential oil selected from the group consisting of carvacrol, cinnemaldehyde, cineole, sabinene, thujaplicin or a mixture thereof or incorporating said essential oils selected from the group consisting of: cinnamon oil, oregano oil, eucalyptus oil, nutmeg oil, honokitioi oil or a mixture thereof, and wherein said polyolefin-based polymeric matrix is selected from the group consisting polyethylene (PE), polypropylene (PE), polystyrene (PS) and ethylvinylacetate (EVA), and wherein said polymeric matrix also includes a crosslinking agent selected nano calcium carbonate, calcium carbonate, starch, cellulose or a mixture thereof and wherein the nano calcium carbonate is also a reinforcing agent.

2. The film of claim 1, wherein said microbial active agent of essential oil or essential oil is microencapsulated,

3. The film of claim 2 wherein said microencapsulating agent is selected from the group consisting of: -cyclodextrin, -cyclodextrin, or silica clay.

4. The film of claim 1 wherein said polymeric matrix is a matrix of polyethylene,

5. The film of claim 4, wherein said polyolefin matrix is a matrix of high density polyethylene or low density polyethylene.

6. The film of claim 5, wherein said polyolefin matrix is a matrix of low density polyethylene.

7. The film of claim 1, wherein said antimicrobial active of essential oil is selected from cinnamaldehyde, carvacrol or a mixture thereof.

8. The film of claim 7, wherein said antimicrobial active of essential oil is cinnamaldehyde.

9. The film of claim 7, wherein said antimicrobial active of essential oil is carvacrol.

10. The film of claim 1, wherein said antimicrobial active of essential oil is oil of oregano.

11. The film of claim 1 wherein the antimicrobial active of essential oil is cinnamon oil.

12. The film of claim 1, wherein said antimicrobial active of essential oil or said essential oil is present in the polymer matrix in an amount between 1-5%.

13. The film of claim 1, wherein said crosslinking agent is present in the polymer matrix in an amount between 3-5%.

14. The film of claim 1, wherein said encapsulating agent is -cyclodextrin.

15. The film of claim 1, wherein said crosslinking agent is nano calcium carbonate.

16. The film of claim 1, wherein the ratio PE:PE essential microbial agent or agent:essential oil is in the range 99/1 to 95/5 w/w.

17. The film of claim 16, wherein the ratio PE:PE essential microbial agent or agent:essential oil is 99/1% w/w.

18. The film of claim 18, wherein the ratio PE:PE essential microbial agent or agent:essential oil is 97/3% w/w.

19. The film of claim 16, wherein the ratio PE:PE essential microbial agent or agent:essential oil is 95/5% w/w.

20. Process for microencapsulating one antimicrobial active of essential oil selected from the group consisting of: carvacrol, cinnemaldehyde, cineol, sabinene, thujaplicin or a mixture thereof or incorporates said essential oil selected from the group consisting of: cinnamon oil, oil oregano oil, eucalyptus oil, nutmeg oil, honokitiol oil or a mixture thereof, -ciclodextirn, comprising: a) solubilizing -cyclodextrin in a water/ethanol solution 2:1 under constant stirring at a temperature of 55oC, and preparing separately a solution of the active agent of essential oil or said essential oil in 10% ethanol v/v; b) adding slowly the solution of said active agent essential oil or said essential oil to the solution with -cyclodextrin, mixing 55oC then lower the temperature to 25 C. and stirring to thereby refrigerate to 7 C., allowing precipitation cold, and then filtered under vacuum to finally allow drying of the precipitate.

21. Process for preparing film of claim 1, comprising: a) melting a polyolefin selected from polyethylene (PE), polypropylene (PE), polyestyrene (PS) and ethylvinylacetate (EVA), and adding an antimicrobial active agent of essential oils selected from the group consisting of essential oil: carvacrol, cinnemaldehyde, cineol, sabinene, thujapicin or a mixture thereof or incorporates said essential oils selected from the group consisting of: cinnamon oil, oregano oil, eucalyptus oil, nutmeg oil, honokitiol oil or a mixture thereof, mixing until homogeneous, where the mixture is prepared in proportions 99/1 to 95/5% w/w PE:antimicrobial active of essential oil or PE:essential oil, b) adding nano calcium carbonate together with the antimicrobial active up to 5% by weight relative to the polymer; and c) preparing the film pressing at 170 C. and 344 KPa and pressure after placing the mixture in a mold, and subsequently cooling to remove the film formed from the mold.

22. The method of claim 21, further characterized in step a) microencapsulating said antimicrobial active of essential oil or essential oil in said -cyclodextrin.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0020] FIG. 1 shows the IR spectra pure -cyclodextrin, carvacrol and cinnamaldehyde pure, and -cyclodextrin microcapsule/carvacrol (B-CD-Car) and -cyclodextrin/Cinemaldehido (b-CD-Cin).

[0021] FIG. 2 shows DSC thermograms -cyclodextrin (b-CD) and -cyclodextrin microcapsule/carvacrol (b-CD-Car) and -cyclodextrin/cinnamaldehyde (B-CD-Cin).

[0022] FIG. 3 shows The TGA thermogram of b-CD and inclusion complexes b-CD/cinnamaldehyde (b-CD-Cin) obtained by a oprecipitation method.

[0023] FIG. 4 shows SEM micrograph taken at (A) b-CD, (B) b-CD cinnamaldehyde and (C) b-CD-carvacrol, by a coprecipitation method.

[0024] FIG. 5 shows IR spectra polyethylene, cinnamaldehyde, b-CD, polyethylene/b-CD-Cin and polyethylene/Cin.

[0025] FIG. 6 shows IR spectra polyethylene, carvacrol, b-CD, polyethylene/b-CD-Car and polyethylene/Car.

[0026] FIG. 7 shows DSC thermograms for films, PE only, PE+Cinnamaldehyde 5%, PE+b-CD-cinnamaldehyde 5% PE+b-CD cinnamaldehyde 5% (active ingredient).

[0027] FIG. 8 shows DSC thermograms for films, PE only, PE+Carvacrol 5%, PE+b-CD-Carvacrol 5% PE+b-CD-carvacrol (5% active).

[0028] FIG. 9 shows thermograms TGA polyethylene (PE), polyethylene-cinnamaldehyde microcapsules (PE+b-CD-Cin) and carvacrol (PE+b-CD-Car).

[0029] FIG. 10 shows the carbonyl of PE and PE/CaCO.sub.3 at different irradiation times.

DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention relates to a film for packaging fruit and vegetables, comprising a polyolefin-based polymer matrix incorporating an active antimicrobial agent (biocide or fungicide) of an essential oil selected from the group consisting of carvacrol, cinnemaldehyde, cineol, sabinene, thujaplicin or a mixture thereof, or incorporating said essential oil selected from the group consisting of: cinnamon oil, oregano oil, eucalyptus oil, nutmeg oil, honokitiol oil or a mixture thereof, which may be microencapsulated, and further comprising a crosslinking agent and microencapsulation process, said antimicrobial active of essential oil or said essential oil; and process for preparing the film.

[0031] This film is an intelligent film for packaging of fruits and vegetables, a polyolefin-based polymer selected from polyethylene (PE), polypropylene (PE), polystyrene (PS) and ethylene vinyl acetate (EVA) and said antimicrobial essential oil microencapsulated or said oil essential that may optionally be microencapsulated, wherein the encapsulating agent is selected from the group consisting of: cyclodextrin (- or -), clay or silica; and further comprises a crosslinking agent selected nano calcium carbonate, calcium carbonate, starch, cellulose or a mixture thereof. Said film has antimicrobial properties (biocides or fungicides), and upon completion of their life cycle, is environmentally degradable.

[0032] In one embodiment of the present invention they were used as antimicrobial actives or fungicide actives: cinnemaldehyde, carvacrol, and essential oils including oregano oil and cinnamon oil, which were previously characterized by infrared spectroscopy analysis (FT-GO). To avoid volatilization or decomposition of essential oils under the conditions of the extrusion process, these were microencapsulated first in order to preserve the active ingredient. Here, variables encapsulation of oils in cyclic oligosaccharides as beta-cyclodextrin, were established. Subsequently, these encapsulated oils were characterized by various spectroscopic and instrumental techniques such as infrared spectroscopy FT-IR, UV-Vis, differential analysis (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SE). Using the techniques mentioned, it was confirmed that the essential oil was incorporated into the beta-cyclodextrin.

[0033] Beta-ciciodextrina allowing satisfactory encapsulation of essential oils.

[0034] As shown in the results, the active ingredients including carvacrol and cinnemaldehyde, are thermally stable, and need not be microencapsulated having a high percentage of fungicide potency when incorporated directly into the polyethylene matrix. Furthermore essential oils, especially oregano oil, need to be microencapsulated because they are more volatile compounds and processing may be loss of these, demonstrating their lower fungicidal properties, being microencapsulated equivalent to 1% its compound, fungicidal activities of 40% is observed, microencapsulation stabilizes essential protecting them of decomposition at high processing temperatures.

Examples

[0035] 1. Preparation and Results of Microcapsules -Cyclodextrin/Active Ingredient

[0036] The coprecipitation method was used for the preparation of microcapsules of -cyclodextrin/essential oil or -cyclodextrin/active agent or antimicrobial agents of an essential oil. We proceeded despite an amount of cyclodextrin - and solubilized in a water/ethanol solution 2:1 in a reactor under constant agitation at a temperature of 55oC in parallel it is prepared a solution of active agent in ethanol 10% v/v. Once the -cyclodextrin solubilizes a slowly active agent is added to the solution, mixing for 30 minutes 55oC. Then, the temperature 25oC decreases and under stirring for 4 hours. The final solution is left under refrigeration for 7oC within 12 hours, finally the cold precipitate was recovered by vacuum filtration and dried in an oven for 24 hours. [19-21]

[0037] Determination of Encapsulation Efficiency Performance.

[0038] The encapsulation efficiency was quantitated by UV spectroscopy in a UV-visible spectrophotometer Weisser SPECORD100. For this a calibration curve using different concentrations previously performed. The encapsulation efficiency (EE), were obtained from the following equations

E.E=mass of active agent obtained/initial mass of the agent*100

[0039] The microcapsules obtained were characterized by spectroscopic techniques such as infrared (FT-IR), UV-visible spectrophotometry and differential scanning calorimetry (DSC), thermogravimetric analysis TGA and scanning electron microscopy (SEM), see FIGS. 1-4 and 6-10.

[0040] 2. Preparation of Polyethylene-Based Films (PE) and Antimicrobial Active Ingredient.

[0041] 2.1. Preparation of Mixed Polymer/Antimicrobial Active by Melt Mixing:

[0042] The mixtures were prepared on a twin screw Brabender equipment. The equipment was preheated to 120oC and 12 rpm for 5 minutes to allow the polymer to melt. Cinnamon oil (A. cinnamon), oregano oil (A. oregano), carvacrol (Cary), cinnemaldehyde (Cin), beta-cyclodextrin-cavacrol (b-CD-Car). Then, an antimicrobial essential oil selected from the group consisting of added b-CD-Car), beta-cyclodextrin cinemaldehido (b-CD-Cin) and mixed for 2 minutes at 120 rpm until fully homogeneous. Mixtures were studied, varying the amount of said antimicrobial agent, and mixtures 99/1, 97/3 and 95/5% w/w were prepared. The mixtures were formed PE/A. Cinnamon, PE/A. Oregano, PE/Carv, PE/Cin, PE/b-CD-Car and PE/b-CD-Cin, polyethylene alone (100%). Additionally together with the active agent (cinnemaldehyde or carvacrol), nano calcium carbonate at 5% by weight was incorporated relative to the weight of the polymer, which allows degradation of the polymer.

TABLE-US-00001 TABLE NO. 1 Ratio polyethylene (PE)/antimicrobial active principle used in the blends B-CD mass: mass of -Cyclodextrin, AA mass: mass of active agent % Active Ingredient Mass Mass Film antimicrobial b-CD A.A PE + A. Cinnamon 1 0 0.35 3 0 1.05 5 0 1.75 PE + b-CD/A. Cinnamon 1 0.28 0.07 3 0.85 0.20 5 1.40 0.35 PE + A. Oregano 1 0 0.35 3 0 1.05 5 0 1.75 PE + b-CD-A. Oregano 1 0.28 0.07 3 0.85 0.20 5 1.40 0.35 PE + Cinamaldehyde 1 0 0.35 3 0 1.05 5 0 1.75 PE + b-CD/Cinamaldehyde 1 0.28 0.07 3 0.85 0.20 5 1.40 0.35 PE + Carvacrol 1 0 0.35 3 0 1.05 5 0 1.75 PE + b-CD-Carvacrol 1 0.28 0.070 3 0.85 0.200 5 1.40 0.350 Mass b-CD: Mass -Cyclodextrin, mass A.A: Mass of active ingrediente

[0043] 2. Preparation of Films by Pressing Molten PE:

[0044] The films were obtained by pressing at 170 and 344 C and KPa (50 psi) pressure in a Scientific, Engineering team LabTech. Once obtained the polymer mixtures/antimicrobial agent, these were placed in a mold of 12 cm12 cm and 1 mm thick, then a press for 3 minutes, then the plates were cooled and removed performed.

[0045] 3. Characterization of Films of Polyethylene Films with Antimicrobial Active

[0046] The films obtained were characterized by infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), also the mechanical properties were studied by tensile deformation and its antimicrobial properties against the growth of Botrytis cinerea.

[0047] 3.1. Infrared Spectroscopy (FTIR) IR spectra were obtained using a Perkin Elmer FTIR-BX a range from 600 to 4000 cm 1.

[0048] 3.2. Differential Scanning calorimetry (DSC): Measurements were performed on a Mettler DSC823, with a heating rate of 10 min.sup.1 in N.sub.2 atmosphere; the samples were heated from 25 to 180oC.

[0049] 3.3. Thermogravimetric analysis (TGA): Measurements were performed on a Netzsch-TG209 F1 Libra computer with a heating rate of 10oC min.sup.1 in inert atmosphere, the samples were heated from 25o to 600oC.

[0050] 3.4. Deformation Tensile Test: The mechanical properties of the materials were determined by tensile-strain in an Instron dynamometer HP D-500 at a strain rate of 50 mm/min at room temperature.

[0051] Samples were prepared cutting probes of tests from a plate of 1 mm thickness, using a steel mold according to ASTM D638. At least 4 determinations were performed by material reporting a simple average value.

[0052] 4. Study Fungicidal Properties:

[0053] Colony counting method: This method quantifies the fungicidal activity of the studied films. The samples and controls were cut into squares of 2.52.5 cm and sterilized. Subsequently the same were inoculated in sterile saline (SF) from 110.sup.4 and 510.sup.6 spores of the fungus B. cinerea, 500 L were taken and deposited on the surface of the films for 8 hours at room temperature. Subsequently, the films are deposited in 10 mL falcon tubes using SF 50 mL, 500 L of the recovered suspension are taken and are diluted in 4.5 mL of SF. Then, 200 L are taken and plated on agar Sabouraud by rake technique in duplicate and allowed to incubate for 96 hours at room temperature. Finally, the elapsed time colony forming units (CFU) are quantified and the percentage reduction is obtained by the following equation

% Reduction=((CM)/C)*100

[0054] wherein C=Count CFU/mL Control

[0055] M=count CFU/mL sample

[0056] 5. Study Film Deterioration by Incorporating CaCO.sub.3

[0057] The effect of incorporating calcium carbonate nanoparticles in the degradation of polyethylene in a chamber that simulates solar aging was studied over a period of three months. Movies of 55 cm were placed in the chamber of degradation (brand Suntest/Atlas XLS 2200 W), irradiation was performed using sunscreens (borosilicate) which provides an irradiance of 550 Wm.sup.2 (USE 4892/DIN 53387). It was studied at different aging times carbonyl index of virgin polyethylene films and polyethylene CaCO.sub.3 nanoparticles. Degradation was determined by measuring the carbonyl index (CI) as the ratio of the optical density of the band of the carbonyl group at 1715 cm.sup.1 with the vibrations of CH.sub.2 1465 cm.sup.1.

[0058] 3. Results

[0059] 3.1 Microencapsulation of Essential Oils or Actives in the -Cyclodextrin

[0060] IR Spectroscopy

[0061] In FIG. 1, it is shown the FT-IR spectra for the active ingredients (Cinnemaldehyde, carvacrol), -cyclodextrin and micropcapsules of -cyclodextrin/active ingredient. The -designation with cyclodextrin and active substances: carvacrol (b-CD-Car) and cinnamaldehyde (b-CD-C in) respectively.

[0062] FIG. 2 shows the spectrum for the active ingredients encapsulated in -cyclodextrin. Microcapsule obtained: -cyclodextrin7Carvacrol (b-CD-Car) and -cyclodextrin/Cinnemaldehyde (b-CD-Cin). For carvacrol (b-CD-Car) appears signals near 1300-1400 cm.sup.1 corresponding mainly to C-Oil interactions of the aromatic ring, as shown for cinnamaldehyde (b-CD-Car) having a signal close to 1670 cm.sup.1 corresponding to a CO characteristic of this compound.

[0063] Microencapsulation of essential oils of oregano and cinnamon was also verified by infrared IR.

[0064] All these signals are confirming that the encapsulation process of different antimicrobial active ingredients studied in the -cyclodextrin cavity was satisfactory.

[0065] By spectrophotometry UV-Visible encapsulation efficiency (EE) was determined at different stirring rates for all active agents by the following equation:

EE.=agent mass obtained/initial mass of agent100(Equation 1)

[0066] From the results, it can be seen that the values of EE increased with increasing agitation reaching 90% for 1000 rpm. This indicates that the agitation plays an important role, as it can facilitate the process of inclusion of hydrophobic antimicrobial active ingredients within the cavity of the -cyclodextrin. Moreover, no differences between essential oils and antimicrobial active principles are mainly appreciated, this indicates that although the oils have a wide variety of compounds can be incorporated into these encapsulanting agent.

[0067] Thermal Analysis

[0068] DSC thermograms obtained for the -cyclodextrin and the microcapsules with active principles carvacrol (b-CD-Car) and cinnamaldehyde (b-CD-Cin) (FIG. 2). An endothermic signal near 130oC characteristic of the -cyclodextrin is observed in the case of microcapsules a less intense signal is recorded with a small shift for both antimicrobial active, attributed to interaction of the active principles b-CD. The change in the endothermic signal and the displacement of this indicates that the inclusion of antimicrobial active modifies the crystalline structure of the cyclodextrin.

[0069] FIG. 3 shows the TGA thermogram for b-CD and (b-CD-Cin). In the case of b-CD that has a peak near 330oC corresponding to the thermal degradation of this. For microcapsules b-CD-Cin signal 325oC corresponding to the b-CD, and other signal around 260oC and attributed to the degradation of cinnamaldehyde, the TGA thermogram for pure cinnamaldehyde seen shows the beginning close to the degradation and the degradation peak is observed near the 205oC. With this analysis along with corroborate the incorporation of active agent in the b-CD, the protective effect is also appreciated that encapsulation gives the active ingredient in high temperature conditions. Similar behavior was found for films containing carvacrol and b-CD.

[0070] By scanning electron microscopy (SEM), see FIG. 6, shows that the microcapsules b-CD-Car and B-CD-Cin Carvacrol, present a different morphology to the b-CD pure, this change is attributed to the change in the crystal structure of the b-CD product incorporating the active agents.

[0071] The microcapsules have an irregular shape, it is present regions where the microcapsules are agglomerated, but some with good dispersion having an average size of 4 m.

[0072] Using the above techniques it was confirmed that the antimicrobial active ingredients incorporated into the -cyclodextrin allows satisfactory encapsulation.

[0073] As the polymer matrix of low density polyethylene (LDPE) was used, polyethylene is generally characterized as a semicrystalline polymer, with good chemical resistance and processability, good electrical insulator, has some degree of flexibility. Meanwhile LDPE has a high degree of branching, which hinders the ordering of the polymer chains. It is an amorphous polymer with low density (0.92 to 0.94 g/cm.sup.2), soft and flexible. It is used in various applications, from plastic bags to electrical insulation.

[0074] 3.2 Characterization of the Films of Antimicrobial Active Infrared Spectroscopy (IR)

[0075] FIG. 6 shows the IR spectra obtained for polyethylene (PE), cinnamaldehyde (Cin), -cyclodextrin (b-CD), polyethylene/b-CD-Cin and polyethylene/Cin. Signals characteristics of polyethylene also bands characteristic of cinnamaldehyde and b-CD are observed. Note that in films containing the active agent without encapsulation, the appearance of a signal between 1500-1700 cm.sup.1, shows that although this overlap corresponds to a signal characteristic of cinnamaldehyde, for films with microcapsule b-CD-cinamaldehyde a signal appears in the region between 1000-3000 cm.sup.1 feature of the b-CD, the case of carvacrol (FIG. 7), a similar effect to the case of the film shown at 5% of the agent without encapsulating a signal appears between 1550-1580 cm.sup.1, characteristic of carvacrol, for the case of the microcapsule film, clearly shows the signals characteristic of the b-CD to 3500 cm.sup.1 and between 1100-1150 cm.sup.1, this confirms that even after the processes, both melt mixing, pressing as the active agent is entrapped in the matrix.

[0076] Analysis and Thermal Stability of PE Films with the Active Agent

[0077] FIGS. 8 and 9 show DSC thermograms for the polyethylene film alone and the films cinnamaldehyde, Carvacrol, containing 5% antimicrobial active loading and microcapsule b-CD-cinnamaldehyde, b-CD-Carvacrol (containing 1% of the agent in the load). signal close crystalline melting is observed at 110oC for the case of polyethylene alone, for all films studied either with the antimicrobial active ingredient unencapsulated and incorporating microcapsule, it can be seen that there are no major differences in virgin polyethylene as to exhibit thermal behavior, crystalline melting signal for all remains in the range between 110 and 115oC. Then, the incorporation of antimicrobial active either encapsulated or not encapsulated, does not affect the thermal properties of the material.

[0078] FIG. 10 shows the TGA thermograms for both PE, as for microcapsules b-CD-Cin and b-CD-car 5% under a nitrogen environment. In the case of cinnamaldehyde, the thermogram no differences with polyethylene without incorporating the active compound, so that the presence of active agent within the matrix not significantly affects the degradation of the film obtained. However in the case of carvacrol, a signal close to 305 C. attributed to a thermal decomposition of the -cyclodextrin confirmed the presence of the microcapsules within the matrix can be seen. By both analyzes, DSC and TGA, it is confirmed that the incorporation of the microcapsules into the matrix does not affect the thermal properties of the films compared to virgin polyethylene.

[0079] Activity films obtained by the colony counting method: Tables 2 shows the results obtained for the polymer films with carvacrol and cinnamaldehyde alone and their essential oils (oregano, cinnamon), along each encapsulated in the -cyclodextrin. With increasing active agent (cinnemaldehyde and carvarcrol) increased the yield percentage reduction up to 99.9%, for both active agents are provided when the loading was 5%, both compounds show a fungicidal activity. The contrary for essential oils so may be because they are less stable at high temperatures, volatizing during the process. When encapsulated compounds are incorporated into the film, the fungicidal effect is less reaching a 31.4% carvacrol when the load was 5% by weight. This is primarily because the amount of active ingredient that is incorporated into the inclusion complex is less, equivalent to 1%. Moreover one should consider that the release of the active ingredient to the surface of the film is slower and requires more time. Otherwise for films without complex, where the active agents are entrapped in the polymer matrix and diffusion to the surface it is much faster and in greater quantity generating this difference in fungicidal activity.

TABLE-US-00002 TABLE 2 Percentage reduction in colony forming units (CFU) of films by colony counting method Ratio PE/ Fungicide Film load (%) Activity (%) PE + A. Cinnamona 99/1 9.,4 97/3 31.2 95/5 70.5 PE + A. Oregano 99/1 12.6 97/3 46.8 95/5 38.9 PE + Cinamaldehyde 99/1 85.3 97/3 93.7 95/5 99.9 PE + Carvacrol 99/1 25.4 97/3 92.5 95/5 99.9 PE + b-CD-A. Cinnamon 99/1 24.5 97/3 31.2 95/5 39.3 PE + b-CD-A. Oregano 99/1 15.7 97/3 20.8 95/5 41.4 PE + b-CD-Cinamaldehyde 99/1 n.d 97/3 n.d 95/5 20 PE + b-CD-Carvacrol 99/1 27.9 97/3 n.d 95/5 31.4
Effect of Incorporation of Calcium Carbonate into Polyethylene

[0080] In Table 3, the mechanical properties of nanocomposites for PE/CaCO.sub.3 are presented. Significant changes can be seen in the studied parameters, on the one hand an increase of up to 25% in Young's modulus is, which means that to deform the nanocomposite greater effort is needed with respect to the matrix without adding nanoparticles. This is because the nanoparticles generate new nucleation centers forming more spherulites and a smaller size, this crystallinity or compact arrangement of the chains are responsible for giving rigidity to the polymer.

[0081] The incorporation of nanoparticles of calcium carbonate generated new centers of fracture with the addition of 5 and 8%, because the amorphous region and the chains having mobility are affected by the addition of these reducing their mobility, this may be due to agglomerations of the nanoparticles in the polymer matrix.

[0082] Optimum incorporation is performed with the addition of 5% improving 20% its stiffness, values at 8% do not show a wide variation due to the low dispersion of the nanoparticles in the matrix.

TABLE-US-00003 TABLE 3 Mechanical properties of nanocomposites for CaCu 3 using as polyethylene low density matrix Mdulus ofe Elastic limito r Elongatio Particles Young fluency point breaking off CaCO.sub.3 Loading (E)(Mpa) (y) (Mpa) (%) S/P S/N 202 7 7.71 0.03 60 8 Nanoparticles 3% 230 7 8.38 0.15 59 10 Nanoparticles 5% 250 4 8.40 0.09 42 3 Nanoparticles 8% 254 10 8.08 0.14 39 1

[0083] The effect of incorporating calcium carbonate nanoparticles in the degradation of polyethylene in a chamber that simulates solar aging was studied over a period of three months. Films 5 cm5 cm were put into the chamber degradation Suntest mark/Atlas XLS 2200 W, irradiation was performed using sunscreens (borosilicate) which provides an irradiance of 550 Wm.sup.2 (USE 4892/DIN 53387). A different aging times carbonyl index of virgin polyethylene films and polyethylene CaCO.sub.3 nanoparticles was studied. Degradation was determined by measuring the carbonyl index (CI) as the ratio of the optical density of the band of the carbonyl group at 1715 cm.sup.1 with the vibrations of CH.sub.2 1465 cm.sup.1.

[0084] Infrared polyethylene non-irradiated and after irradiation for 28 days with the addition of nanoparticles a band at 1700 cm.sup.1 was observed due to the degradation suffered polyethylene in time, by the incorporation of nanoparticles. Can interfere nanoparticles are accelerating the degradation of polyethylene.

[0085] In FIG. 6 the carbonyl of polyethylene PE/CaCO.sub.3 different irradiation times is presented. It can be seen increased carbonyl index is much higher incorporating nanoparticles CaCO.sub.3 to polyethylene, these nanoparticles accelerated degradability polyethylene. The best results were obtained for films with 5% active (cinnemaldehyde or carvacrol) and 5% nanoparticles of calcium carbonate so that these conditions are suitable for preparing an intelligent film or film having fungicidal properties but at the same time it is degraded environmental conditions.