U.S. patent application number 15/216580 was filed with the patent office on 2016-11-10 for use of photosensitive molecules and metal complexes as oxygen scavenger elements.
This patent application is currently assigned to BASF SE. The applicant listed for this patent is BASF SE. Invention is credited to Enrico GALFRE, Edoardo MENOZZI, Massimiliano SALA.
Application Number | 20160325267 15/216580 |
Document ID | / |
Family ID | 42131287 |
Filed Date | 2016-11-10 |
United States Patent
Application |
20160325267 |
Kind Code |
A1 |
MENOZZI; Edoardo ; et
al. |
November 10, 2016 |
USE OF PHOTOSENSITIVE MOLECULES AND METAL COMPLEXES AS OXYGEN
SCAVENGER ELEMENTS
Abstract
An oxygen-scavenging composition for food packaging applications
comprising (I) a polymeric resin, (II) one or more oligomeric
photosensitizers, (Ill) a metal salt, (IV) a sacrificial oxidizable
substrate and optionally (V) additional components is provided.
Inventors: |
MENOZZI; Edoardo; (Basel,
CH) ; SALA; Massimiliano; (Castelnuovo Rangone (MO),
IT) ; GALFRE; Enrico; (Basel, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BASF SE |
Ludwigshafen |
|
DE |
|
|
Assignee: |
BASF SE
Ludwigshafen
DE
|
Family ID: |
42131287 |
Appl. No.: |
15/216580 |
Filed: |
July 21, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13511237 |
Aug 13, 2012 |
9441066 |
|
|
PCT/EP2010/068371 |
Nov 29, 2010 |
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15216580 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08K 5/132 20130101;
C08F 290/00 20130101; B32B 27/18 20130101; C08L 23/06 20130101;
B32B 27/08 20130101; C08L 23/00 20130101; C08K 5/098 20130101; C08L
57/00 20130101; C08L 23/06 20130101; C08K 2201/012 20130101; B01J
20/262 20130101; B01J 20/223 20130101; C08L 45/00 20130101; C08L
23/00 20130101; B32B 2307/74 20130101; C08L 2666/02 20130101; C08L
2666/04 20130101; B65D 81/24 20130101; B32B 2439/70 20130101 |
International
Class: |
B01J 20/26 20060101
B01J020/26; B32B 27/18 20060101 B32B027/18; B65D 81/24 20060101
B65D081/24; B32B 27/08 20060101 B32B027/08; B01J 20/22 20060101
B01J020/22; C08L 23/06 20060101 C08L023/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 2, 2009 |
EP |
09177743.3 |
Claims
1. An oxygen-scavenging composition for food packaging applications
comprising (I) a polymeric resin, (II) one or more oligomeric
photosensitizers, (III) a metal salt, (IV) a sacrificial oxidizable
substrate and optionally (V) additional components.
2. The oxygen-scavenging composition according to claim 1 wherein
the polymeric resin is a thermoplastic polymer selected from the
group consisting of homo- or copolymers of olefin monomers,
copolymers of olefin monomers with diolefin monomers, cyclic
olefins, copolymers of one or more 1-olefins or diolefins with
carbon monoxide, copolymers of one or more 1-olefins and diolefins
with carbon monoxide and polyvinyl alcohol.
3. The oxygen-scavenging composition according to claim 1 wherein
the metal salt is based on Co, Ce, Mn, Cu, Ni or Vd.
4. The oxygen-scavenging composition according to claim 1 wherein
the sacrificial oxidizable substrate is selected from the group
consisting of polybutadiene, polyester, squalane, squalene,
polystyrene, poly-limonene, poly alpha pinene, poly beta pinene,
polynorbornene, polylactic acid and a mixture of linear and
branched alkyl chain C.sub.6-C.sub.30 alcohols.
5. The oxygen-scavenging composition according to claim 1 which
further comprises one or more components selected from the group
consisting of fillers, reinforcing agents, pigments, light
stabilizers, antioxidants, antislip or antiblock additives,
plasticizers, optical brighteners, antistatic agents and blowing
agents.
6. The oxygen-scavenging composition according to claim 1 with the
proviso that components (I) and (IV) are different.
7. The oxygen-scavenging composition according to claim 1, wherein
component (IV) is a polyterpenic resin.
8. An article containing a composition as defined in claim 1.
9. An article according to claim 8, which is a film, a sheet or a
laminate.
10. An article according to claim 9 which is a coextruded
multilayer film.
11. An article according to claim 9 which is a food packaging.
Description
[0001] It is known that many oxygen sensitive products, including
food products such as meat and cheese, smoked and processed
luncheon meats, as well as non food products such as electronic
components pharmaceuticals and medical products deteriorate in the
presence of oxygen. Both the color and the flavor of foods can be
adversely affected. The oxidation of lipids within the food product
can result in the development of rancidity.
[0002] Limiting the exposure to oxygen provides a means to maintain
and enhance the quality and shelf-life of the packaged product,
especially in the food industry. The removal of oxygen from the
packaged foods and building barriers against oxygen penetration
during storage represents an important objective for the packaging
technologist. For example packaging a food product in a package
capable of minimizing oxygen exposure is a means to maintain the
quality of the packaged product over an extended time and to retard
spoilage of the product so that it is maintained in inventory
longer without wastage and the need of restocking and
replacement.
[0003] In the food packaging industry, several techniques have been
developed to limit oxygen sensitive packaged materials to oxygen
exposure. Such techniques include the use of barrier material (with
low permeability to oxygen) as part of the packaging; the inclusion
of items capable of consuming oxygen other then the packaging
material (through the use of sachets with material capable of
reacting with oxygen); and the creation of a reduced oxygen
environment within the package (e.g. modified atmosphere
packaging--MAP--and vacuum packaging).
[0004] Even if each of the above techniques has its place in the
industry, it is well recognized that the inclusion of an oxygen
scavenger as a part of the packaging article is one of the most
desirable means of limiting oxygen exposure.
[0005] U.S. Pat. No. 5,744,056, U.S. Pat. No. 6,369,148 and U.S.
Pat. No. 6,586,514 describe an oxygen scavenging composition
comprising an oxidizable metal component, an electrolyte component,
and a non-electrolytic acidifying component that is thermally
stable at thermoplastic resin melt fabrication temperatures.
WO2006089895 discloses a similar system wherein the electrolytic
component participating in the oxidation reaction is obtained by
hydrolysis of a Lewis acid salts and/or theirs adducts. One
difficulty with scavenger systems of this type is the relative
inefficiency of the oxidation reaction within the polymer matrix.
Indeed, the scavenger composition must be employed usually at high
loading, leading to cost, compatibility, color and transparency
issues. In EP-A-1 423 456 the concentration of the metal is limited
to less than 0.25% in order to obtain a more transparent plastic
object, limiting significantly its effectiveness.
[0006] In this patent the combination of transition metal
components with organic and/or inorganic photoactive molecules and
sacrificial oxidizable substrates is describe for removing oxygen
into a sealed transparent food package and be an excellent tool for
increasing the shelf-life stability and preserve organoleptic food
properties.
[0007] The use of organic photoactive molecules like anthraquinone
or benzophenone derivatives in synthetic thermoplastics resin is
claimed since the early seventies. Nevertheless these additives
furnish various inconveniences because they are generally compounds
of low molecular weight. For example, an additive of relatively low
boiling point or a sublimable additive undergoes evaporation,
sublimation when the resin is molded, formed or otherwise processed
under heat. Furthermore, poor compatibility between the functional
agent and the resin causes bleeding or blooming on the surface of
the resin during its long-term use. Furthermore, blooming can cause
additive leaching particularly undesirable when plastic products
are used in contact with food. In this patent such problems have
been taken into consideration and oligomeric anthraquinone or
benzophenone designed according to the resin's needs, can solve the
issues mentioned above.
[0008] Thus, while a variety of approaches to maintaining or
reducing oxygen levels in packaged items have been advanced, there
remains a need for improved oxygen-scavenging composition and
packaging materials utilizing the same.
[0009] An object of the present invention is therefore to provide
improved oxygen-scavenging compositions and packagings. Another
object is to provide low costs, oxygen-scavenging compositions of
improved efficiency. Another object is to provide oxygen scavenging
composition that can be used effectively, even at relatively low
levels, in a wide range of active-barrier packaging films and
sheets, including laminated and coextruded multilayer films and
sheets. Another object is ti provide active-barrier packaging
containers that can increase the shelf-life of oxygen-sensitive
products by slowing the passage of external oxygen into the
container, by absorbing oxygen present inside the container or
both. Other objects will be apparent to those skilled in the
art.
[0010] It has been observed that the use of the inventive
oxygen-scavenging composition enhances the resistance of the packed
food products against the oxygen attact.
[0011] Thus the present invention relates to an oxygen-scavenger
composition for food packaging application comprising:
[0012] (I) A polymeric resin preferably a thermoplastic polymers
such as: [0013] Homo and copolymers of olefin monomers such as
ethylene and propylene, but also higher 1-olefins such as 1-butene,
1-pentene, 1-hexene or 1-octen. Preferred is polyethylene LDPE and
LLDPE, HDPE and polypropylene; [0014] Homo- and copolymers of
olefin monomers with diolefin monomers such as butadiene, isoprene
and cyclic olefins such as norbornene; [0015] Copolymers of one ore
more 1-olefins and/or diolefins with carbon monoxide and/or with
other vinyl monomers, including, but not limited to, acrylic acid
and its corresponding acrylic esters, methacrylic acid and its
corresponding esters, vinyl acetate, vinyl alcohol, vinyl ketone,
styrene, maleic acid anhydride and vinyl chloride; [0016] Polyvinyl
alcohol;
[0017] (II) One or more oligomeric organic photosensitizers based
on benzophenone-3,3',4,4'-tetracarboxylic dianhydride, benzophenone
or anthraquinone as defined. The photosensitizer(s) may be present
in total in a concentration from 0.001-10 wt %, preferably 0.01-5
wt % and most preferably 0.1-5 wt % based on the polymeric resin.
Suitable Oligomeric photosensitizes are described in the WO
2009/016083 A1 from line 18 page 3 to line 8 page 23; [0018]
Photosensitizers derived from
benzophenone-3,3',4,4'-tetracarboxylic dianhydride, particularly
such given in the following Table:
TABLE-US-00001 ##STR00001## ##STR00002## [0018] ##STR00003##
##STR00004## ##STR00005## ##STR00006## ##STR00007##
##STR00008##
[0019] Other benzophenone photosensitizers, particularly such given
in the following Table:
TABLE-US-00002 ##STR00009## ##STR00010## [0019] ##STR00011##
##STR00012##
[0020] Photosensitizers bearing an anthraquinone core particularly
such given in the following Table:
TABLE-US-00003 ##STR00013## ##STR00014## [0020] ##STR00015##
##STR00016## ##STR00017## ##STR00018##
[0021] (III) Metal salts based on Co, Ce, Mn, Cu, Ni, Vd.
Preferably these salts are metal salts of fatty acids with a carbon
number raging from C.sub.12 to C.sub.36. Most preferred are metals
carboxylates of palmitic (C.sub.16), stearic (C.sub.18), oleic
(C.sub.18), linolic (C.sub.18) and linoleic (C.sub.18) acid. The
transition metal salt is preferably manganese which may be present
in a total concentration from 0.001-10 wt %, preferably 0.01-5 wt %
and most preferably 0.1-5 wt % based on the polymeric resin. Also
possible are aromatic acids such as benzoic acid. Examples for the
use of these salts are given in the U.S. Pat. No. 3,840,512 and the
U.S. Pat. No. 4,101,720;
[0022] (IV) Sacrificial oxidizable substrates like polybutadiene,
polyester, squalane, squalene, polystyrene, poly-limonene, poly
alpha pinene, poly beta pinene, polynorbornene, polylactic acid,
mixture of linear and branched alkyl chains alcohol (R:
C.sub.6-C.sub.30). Preferably these oxidizable substrates are
present in a total concentration from 0.001-10 wt %, preferably
0.01-5 wt % and most preferably 0.1-5 wt % based on the polymeric
resin; and optionally
[0023] (V) additional components.
[0024] Starting materials for the above said compounds are
commercially available compounds, for example: [0025]
Dihydroxy-anthraquinone [0026]
Benzophenone-3,3',4,4'-tetracarboxylic dianhydride [0027] Manganese
Stearate [0028] Copper Stearate [0029] Poly-alpha-pinene [0030]
Poly-beta-pinene [0031] Poly limonene
[0032] The optional additional components include: [0033] Fillers
and reinforcing agents such as calcium carbonate, silicas, glass
fibres, glass bulbs, talc, kaolin, mica, barium sulfate, metal
oxides and hydroxides, carbon black, graphite, wood flour, flours
of other natural products, synthetic fibers, stearates used as
fillers such as calcium stearate on zinc stearate; [0034] Pigments
such as carbon black, titanium dioxide in its rutil or anatase
forms, and other color pigments; [0035] Light stabilizers,
antioxidants and/or further light stabilizers such as e.g.: 1.
Alkylated monophenols, for example
2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol,
2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol,
2,6-di-tert-butyl-4-isobutylphenol,
2,6-dicyclopentyl-4-methylphenol,
2-(.alpha.-methylcyclohexyl)-4,6-dimethylphenol,
2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol,
2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are
linear or branched in the side chains, for example,
2,6-di-nonyl-4-methylphenol,
2,4-dimethyl-6-(1'-methylundec-1'-yl)phenol,
2,4-dimethyl-6-(1'-methylheptadec-1'-yl)phenol,
2,4-dimethyl-6-(1'-methyltridec-1'-yl)phenol and mixtures thereof.
2. Alkylthiomethylphenols, for example
2,4-dioctylthiomethyl-6-tert-butylphenol,
2,4-dioctylthiomethyl-6-methylphenol,
2,4-dioctylthiomethyl-6-ethylphenol,
2,6-di-dodecylthiomethyl-4-nonylphenol. 3. Hydroquinones and
alkylated hydroquinones, for example
2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone,
2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octadecyloxyphenol,
2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole,
3,5-di-tert-butyl-4-hydroxyanisole,
3,5-di-tert-butyl-4-hydroxyphenyl stearate,
bis(3,5-di-tert-butyl-4-hydroxyphenyl) adipate. 4. Tocopherols, for
example .alpha.-tocopherol, .beta.-tocopherol, .gamma.-tocopherol,
.delta.-tocopherol and mixtures thereof (vitamin E). 5.
Hydroxylated thiodiphenyl ethers, for example
2,2'-thiobis(6-tert-butyl-4-methylphenol),
2,2'-thiobis(4-octylphenol),
4,4'-thiobis(6-tert-butyl-3-methylphenol),
4,4'-thiobis(6-tert-butyl-2-methylphenol),
4,4'-thiobis(3,6-di-sec-amylphenol),
4,4'-bis(2,6-dimethyl-4-hydroxyphenyl)-disulfide. 6.
Alkylidenebisphenols, for example
2,2'-methylenebis(6-tert-butyl-4-methylphenol),
2,2'-methylenebis(6-tert-butyl-4-ethylphenol),
2,2'-methylenebis[4-methyl-6-(.alpha.-methylcyclohexyl)-phenol],
2,2'-methylenebis(4-methyl-6-cyclohexylphenol),
2,2'-methylenebis(6-nonyl-4-methylphenol),
2,2'-methylenebis(4,6-di-tert-butylphenol),
2,2'-ethylidenebis(4,6-di-tert-butylphenol),
2,2'-ethylidenebis(6-tert-butyl-4-isobutylphenol),
2,2'-methylenebis[6-(.alpha.-methylbenzyl)-4-nonylphenol],
2,2'-methylenebis[6-(.alpha.,.alpha.-dimethylbenzyl)-4-nonylphenol],
4,4'-methylenebis(2,6-di-tert-butylphenol),
4,4'-methylenebis(6-tert-butyl-2-methylphenol),
1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane,
2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol,
1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane,
1,1-bis(5-tert-butyl-4-hydroxy-2-methyl-phenyl)-3-n-dodecylmercaptobutane-
, ethylene glycol
bis[3,3-bis(3'-tert-butyl-4'-hydroxyphenyl)butyrate],
bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopentadiene,
bis[2-(3'-tert-butyl-2'-hydroxy-5'-methylbenzyl)-6-tert-butyl-4-methylphe-
nyl]terephthalate, 1,1-bis-(3,5-dimethyl-2-hydroxyphenyl)butane,
2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)propane,
2,2-bis(5-tert-butyl-4-hydroxy2-methylphenyl)-4-n-dodecylmercaptobutane,
1,1,5,5-tetra-(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane. 7.
O-, N- and S-benzyl compounds, for example
3,5,3',5'-tetra-tert-butyl-4,4'-dihydroxydibenzyl ether,
octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate,
tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate,
tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine,
bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate,
bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide,
isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate. 8.
Hydroxybenzylated malonates, for example
dioctadecyl-2,2-bis(3,5-di-tert-butyl-2-hydroxybenzyl)malonate,
di-octadecyl-2-(3-tert-butyl-4-hydroxy-5-methylbenzyl)malonate,
di-dodecylmercaptoethyl-2,2-bis
(3,5-di-tert-butyl-4-hydroxybenzyl)malonate,
bis[4-(1,1,3,3-tetramethylbutyl)phenyl]-2,2-bis(3,5-di-tert-butyl-4-hydro-
xybenzyl)malonate. 9. Aromatic hydroxybenzyl compounds, for example
1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene,
1,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene,
2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol. 10. Triazine
compounds, for example
2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triaz-
ine,
2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-tri-
azine,
2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-t-
riazine,
2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine,
1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate,
1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate,
2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine,
1,3,5-tris(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)-hexahydro-1,3,5-tr-
iazine, 1,3,5-tris(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanurate.
11. Benzylphosphonates, for example
dimethyl-2,5-di-tert-butyl-4-hydroxybenzylphosphonate,
diethyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate,
dioctadecyl3,5-di-tert-butyl-4-hydroxybenzylphosphonate,
dioctadecyl-5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate, the
calcium salt of the monoethyl ester of
3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid. 12.
Acylaminophenols, for example 4-hydroxylauranilide,
4-hydroxystearanilide, octyl
N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate. 13. Esters of
.beta.-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono-
or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol,
i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene
glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol,
diethylene glycol, triethylene glycol, pentaerythritol,
tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide,
3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,
trimethylolpropane,
4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane. 14.
Esters of .beta.-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic
acid with mono- or polyhydric alcohols, e.g. with methanol,
ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol,
1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol,
thiodiethylene glycol, diethylene glycol, triethylene glycol,
pentaerythritol, tris(hydroxyethyl)isocyanurate,
N,N'-bis-(hydroxyethyl)oxamide, 3-thiaundecanol,
3-thiapentadecanol, trimethylhexanediol, trimethylolpropane,
4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane;
3,9-bis[2-{3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dim-
ethylethyl]-2,4,8,10-tetraoxaspiro[5.5]-undecane. 15. Esters of
.beta.-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid with mono-
or polyhydric alcohols, e.g. with methanol, ethanol, octanol,
octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,
1,2-propanediol, neopentyl glycol, thiodiethylene glycol,
diethylene glycol, triethylene glycol, pentaerythritol,
tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide,
3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,
trimethylolpropane,
4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane. 16.
Esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono-
or polyhydric alcohols, e.g. with methanol, ethanol, octanol,
octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,
1,2-propanediol, neopentyl glycol, thiodiethylene glycol,
diethylene glycol, triethylene glycol, pentaerythritol,
tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide,
3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,
trimethylolpropane,
4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane. 17.
Amides of .beta.-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid
e.g. N,
N'-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide,
N,N'-bis(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)trimethylenediamide,
N,N'-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazide,
N,N'-bis[2-(3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyloxy)ethyl]oxami-
de (Naugard.RTM. XL-1, supplied by Uniroyal). 18. Ascorbic acid
(vitamin C) 19. Aminic antioxidants, for example
N,N'-di-isopropyl-p-phenylenediamine,
N,N'-di-sec-butyl-p-phenylenediamine,
N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine,
N,N'-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine,
N,N'-bis(1-methylheptyl)-p-phenylenediamine,
N,N'-dicyclohexyl-p-phenylenediamine,
N,N'-diphenyl-p-phenylenediamine,
N,N'-bis(2-naphthyl)-p-phenylenediamine,
N-isopropyl-N'-phenyl-p-phenylenediamine,
N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine,
N-(1-methylheptyl)-N'-phenyl-p-phenylenediamine,
N-cyclohexyl-N'-phenyl-p-phenylenediamine,
4-(p-toluenesulfamoyl)diphenylamine,
N,N'-dimethyl-N,N'-di-sec-butyl-p-phenylenediamine, diphenylamine,
N-allyldiphenylamine, 4-isopropoxydiphenylamine,
N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine,
N-phenyl-2-naphthylamine, octylated diphenylamine, for example
p,p'-di-tert-octyldiphenylamine, 4-n-butylaminophenol,
4-butyrylaminophenol, 4-nonanoylaminophenol,
4-dodecanoylaminophenol, 4-octadecanoylaminophenol,
bis(4-methoxyphenyl)amine,
2,6-di-tert-butyl-4-dimethylamino-methylphenol,
2,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane,
N,N,N',N'-tetramethyl-4,4'-diaminodiphenylmethane,
1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenyl-amino)propane,
(o-tolyl)biguanide, bis[4-(1',3'-dimethylbutyl)phenyl]amine,
tert-octylated N-phenyl-1-naphthylamine, a mixture of mono- and
dialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono-
and dialkylated nonyldiphenylamines, a mixture of mono- and
dialkylated dodecyldiphenylamines, a mixture of mono- and
dialkylated isopropyl/isohexyldiphenylamines, a mixture of mono-
and dialkylated tert-butyldiphenylamines,
2,3-dihydro-3,3-di-methyl-4H-1,4-benzothiazine, phenothiazine, a
mixture of mono- and dialkylated
tert-butyl/tert-octylphenothiazines, a mixture of mono- and
dialkylated tert-octyl-phenothiazines, N-allylphenothiazine,
N,N,N',N'-tetraphenyl-1,4-diaminobut-2-ene. 20.
2-(2'-Hydroxyphenyl)benzotriazoles, for example
2-(2'-hydroxy-5'-methylphenyl)-benzotriazole,
2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)benzotriazole,
2-(5'-tert-butyl-2'-hydroxyphenyl)benzotriazole,
2-(2'-hydroxy-5'-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole,
2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chloro-benzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-methylphenyl)-5-chloro-benzotriazole,
2-(3'-sec-butyl-5'-tert-butyl-2'-hydroxyphenyl)benzotriazole,
2-(2'-hydroxy-4'-octyloxyphenyl)benzotriazole,
2-(3',5'-di-tert-amyl-2'-hydroxyphenyl)benzotriazole,
2-(3',5'-bis-(.alpha.,.alpha.-dimethylbenzyl)-2'-hydroxyphenyl)benzotriaz-
ole,
2-(3'-tert-butyl-2'-hydroxy-5'-(2-octyloxycarbonylethyl)phenyl)-5-chl-
oro-benzotriazole,
2-(3'-tert-butyl-5'-[2-(2-ethylhexyloxy)-carbonylethyl]-2'-hydroxyphenyl)-
-5-chloro-benzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-(2-methoxycarbonylethyl)phenyl)-5-chloro-b-
enzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-(2-meth-oxycarbonylethyl)phenyl)benzotriaz-
ole,
2-(3'-tert-butyl-2'-hydroxy-5'-(2-octyloxycarbonyl-ethyl)phenyl)benzo-
triazole,
2-(3'-tert-butyl-5'-[2-(2-ethylhexyloxy)carbonylethyl]-2'-hydrox-
y-phenyl)benzotriazole,
2-(3'-dodecyl-2'-hydroxy-5'-methylphenyl)benzotriazole,
2-(3'-tert-butyl-2'-hydroxy-5'-(2-isooctyloxycarbonylethyl)phenylbenzotri-
azole,
2,2'-methylene-bis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazole-2-y-
lphenol]; the transesterification product of
2-[3'-tert-butyl-5'-(2-methoxycarbonylethyl)-2'-hydroxyphenyl]-2H-benzotr-
iazole with polyethylene glycol 300;
##STR00019##
[0035] where
R=3'-tert-butyl-4'-hydroxy-5'-2H-benzotriazol-2-ylphenyl,
2-[2'-hydroxy-3'-(.alpha.,.alpha.-dimethylbenzyl)-5'-(1,1,3,3-tetramethyl-
butyl)-phenyl]-benzotriazole;
2-[2'-hydroxy-3'-(1,1,3,3-tetramethylbutyl)-5'-(.alpha.,.alpha.-dimethylb-
enzyl)-phenyl]benzotriazole. 21. 2-Hydroxybenzophenones, for
example the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy,
4-dodecyloxy, 4-benzyloxy, 4,2',4'-trihydroxy and
2'-hydroxy-4,4'-dimethoxy derivatives. 22. Esters of substituted
and unsubstituted benzoic acids, for example 4-tert-butyl-phenyl
salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoyl
resorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoyl resorcinol,
2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate,
hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl
3,5-di-tert-butyl-4-hydroxybenzoate,
2-methyl-4,6-di-tert-butylphenyl
3,5-di-tert-butyl-4-hydroxybenzoate. 23. Acrylates, for example
ethyl .alpha.-cyano-.beta.,.beta.-diphenylacrylate, isooctyl
.alpha.-cyano-.beta.,.beta.-diphenylacrylate, methyl
.alpha.-carbomethoxycinnamate, methyl
.alpha.-cyano-.beta.-methyl-.beta.-methoxycinnamate, butyl
.alpha.-cyano-.beta.-methyl-.beta.-methoxy-cinnamate, methyl
.alpha.-carbomethoxy-.beta.-methoxycinnamate,
N-(.beta.-carbomethoxy-.beta.-cyanovinyl)-2-methylindoline,
neopentyl tetra(.alpha.-cyano-.beta.,.beta.-diphenylacrylate. 24.
Sterically hindered amines, for example carbonic acid
bis(1-undecyloxy-2,2,6,6-tetramethyl-4-piperidyl)ester,
bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate,
bis(2,2,6,6-tetramethyl-4-piperidyl)succinate,
bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate,
bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate,
bis(1,2,2,6,6-pentamethyl-4-piperidyl)
n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate
of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and
succinic acid, linear or cyclic condensates of
N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and
4-tert-octylamino-2,6-dichloro-1,3,5-triazine,
tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate,
tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,
1,1'-(1,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone),
4-benzoyl-2,2,6,6-tetramethylpiperidine,
4-stearyloxy-2,2,6,6-tetramethylpiperidine,
bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl-2-(2-hydroxy-3,5-di-tert-bu-
tylbenzyl)malonate,
3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione,
bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate,
bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, linear or
cyclic condensates of
N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and
4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of
2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triaz-
ine and 1,2-bis(3-aminopropylamino)ethane, the condensate of
2-chloro-4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-tri-
azine and 1,2-bis(3-aminopropylamino)ethane,
8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-d-
ione,
3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidine-2,5-dione,
3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione,
a mixture of 4-hexadecyloxy- and
4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensate of
N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexa methylenediamine and
4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, a condensate of
1,2-bis(3-aminopropylamino)ethane and
2,4,6-trichloro-1,3,5-triazine as well as
4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No.
[136504-96-6]); a condensate of 1,6-hexanediamine and
2,4,6-trichloro-1,3,5-triazine as well as N,N-dibutylamine and
4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No.
[192268-64-7]);
N-(2,2,6,6-tetramethyl-4-piperidyl)-n-dodecylsuccinimide,
N-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-dodecylsuccinimide,
2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane,
a reaction product of
7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro-[4,5]decane
and epichlorohydrin,
1,1-bis(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphenyl)-
ethene,
N,N'-bis-formyl-N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethy-
lenediamine, a diester of 4-methoxymethylenemalonic acid with
1,2,2,6,6-pentamethyl-4-hydroxypiperidine,
poly[methylpropyl-3-oxy-4-(2,2,6,6-tetramethyl-4-piperidyl)]siloxane,
a reaction product of maleic acid anhydride-.alpha.-olefin
copolymer with 2,2,6,6-tetramethyl-4-aminopiperidine or
1,2,2,6,6-pentamethyl-4-aminopiperidine,
2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidine-4-yl)-N-butylami-
no]-6-(2-hydroxyethyl)amino-1,3,5-triazine,
1-(2-hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperi-
dine, 5-(2-ethylhexanoyl)oxymethyl-3,3,5-trimethyl-2-morpholinone,
Sanduvor (Clariant; CAS Reg. No. 106917-31-1],
5-(2-ethylhexanoyl)oxymethyl-3,3,5-trimethyl-2-morpholinone, the
reaction product of
2,4-bis[(1-cyclohexyloxy-2,2,6,6-piperidine-4-yl)butylamino]-6-chloro-s-t-
riazine with N,N'-bis(3-aminopropyl)ethylenediamine),
1,3,5-tris(N-cyclohexyl-N-(2,2,6,6-tetramethylpiperazine-3-one-4-yl)amino-
)-s-triazine,
1,3,5-tris(N-cyclohexyl-N-(1,2,2,6,6-pentamethylpiperazine-3-one-4-yl)ami-
no)-s-triazine. 25. Oxamides, for example 4,4'-dioctyloxyoxanilide,
2,2'-diethoxyoxanilide, 2,2'-dioctyloxy-5,5'-di-tert-butoxanilide,
2,2'-didodecyloxy-5,5'-di-tert-butoxanilide,
2-ethoxy-2'-ethyloxanilide, N,N'-bis(3-dimethylaminopropyl)oxamide,
2-ethoxy-5-tert-butyl-2'-ethoxanilide and its mixture with
2-ethoxy-2'-ethyl-5,4'-di-tert-butoxanilide, mixtures of o- and
p-methoxy-disubstituted oxanilides and mixtures of o- and
p-ethoxy-disubstituted oxanilides. 26.
2-(2-Hydroxyphenyl)-1,3,5-triazines, for example
2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine,
2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-
,
2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,
2,4-bis(2-hydroxy-4-propyl-oxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazi-
ne,
2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine,
2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazi-
ne,
2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-tr-
iazine,
2-[2-hydroxy-4-(2-hydroxy-3-butyloxypropoxy)phenyl]-4,6-bis(2,4-di-
methyl)-1,3,5-triazine,
2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethy-
l)-1,3,5-triazine,
2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2-
,4-dimethylphenyl)-1,3,5-triazine,
2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethy-
lphenyl)-1,3,5-triazine,
2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine,
2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine,
2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxy-propoxy)phenyl]-1,3,5-triazine-
, 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine,
2-{2-hydroxy-4-[3-(2-ethylhexyl-1-oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis-
(2,4-dimethylphenyl)-1,3,5-triazine,
2,4-bis(4-[2-ethylhexyloxy]-2-hydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-tr-
iazine. [0036] processing additives such as antislip/antiblock
additives, plasticizers, optical brighteners, antistatic agents and
blowing agents.
[0037] Antioxidants may be present in amounts to stabilize the
polymer during processing and forming steps, however large
quantities are undesired in order not to prevent degradation.
[0038] The final products can be any type of plastic product for
food packaging applications, which needs enhanced oxygen scavenger
activities.
[0039] For example, the polymeric component may be used to
manufacture mono- or multilayer plastic films, sheets, laminates,
bags, bottles, styrofoam cups, utensils, blister packages, boxes,
package wrappings. The articles may be manufactured by any process
available to those of ordinary skill in the art including, but not
limited to, extrusion, extrusion blowing, film casting, film
blowing, calendering, injection molding, blow molding, compression
molding, thermoforming, spinning, blow extrusion and rotational
casting. In particular, this is of interest in the area of modify
atmosphere (CO.sub.2, N.sub.2) food packaging. The rate of the
oxygen uptake can simply be adjusted by changing the concentration
of the additives i.e. if higher oxygen scavenger performance is
desired, then higher amount of additives is added.
[0040] The oligomeric organic photosensitizers, metal salts,
sacrificial oxidizable substrates and optionally other additional
components can be admixted with the polymeric resin either
simultaneously or in succession, or also immediately prior to the
actual processing step.
[0041] Hence, the present invention further relates to an article
made of or comprising a composition containing a polymeric resin as
defined above, oligomeric organic photosensitizers as defined
above, metal salt as defined above, sacrificial oxidizable
substrates as defined above and optionally additional components as
defined above.
[0042] The synthesis of the cited examples is best carried out as
described in the following Examples. Incorporation of the various
additives is best performed in a thermal compounding step, mixing
thoroughly the oxidation additives and optional additives, followed
by an extrusion of the physical blend at elevated temperature.
Typically an extruder with suitable screw configuration is used for
this step. The additives can also be added in the form of a
preconfectioned masterbatch produced in a different manner. For the
production of the desired article any appropriate machine can be
used, depending on the final form of the article, for example a
blow extruder in the case of films, a cast extrusion machine in the
case of sheets or an injection-molding machine.
[0043] The invention can be applied in all areas of packaging where
oxygen scavenger activity is desired.
[0044] In particular, this is of interest in the area of modify
atmosphere (CO.sub.2, N.sub.2) food packaging. The rate of the
oxygen uptake can simply be adjusted by changing the concentration
of the additives i.e. if higher oxygen scavenger performance is
desired, then higher amount of additives is added.
[0045] The following examples illustrate the invention without
limiting the scope thereof. All percentages and parts are by
weight, unless stated otherwise.
TABLE-US-00004 Example 1 Structure ##STR00020## Physical form
Yellow solid Melting point 83-93.degree. C. Mn (g/mol) 2744 Data of
thermogravimetric 260.degree. C.: 0.41%; 280.degree. C.: 0.57%;
analysis/weight loss 300.degree. C.: 0.87% Example 2 Structure
##STR00021## Physical form Yellow solid Melting point
166-174.degree. C. Mn (g/mol) 1038 Data of thermogravimetric
260.degree. C.: 1.90%; 280.degree. C.: 2.00%; analysis/weight loss
300.degree. C.: 2.21% Example 3 Structure ##STR00022## Physical
form Slightly brown solid Melting point 127-135.degree. C. Mn
(g/mol) N.A. Data of thermogravimetric 210.degree. C.: 0.51%;
260.degree. C.: 1.13%; 300.degree. C.: 7.47% analysis/weight
loss
[0046] All chemicals were used as received and not purified prior
to synthesis. Synthesis of the above compounds 1, 2, 3 is described
in the WO 2009/016083 A1.
[0047] Riblene GP20.RTM. low density polyethylene has been obtained
from Polimeri Europa; Dercolyte.RTM. is a poly terpene product
obtain from Les Derives Resiniques & Terpeniques; Manganese
Stearate, Mn(C.sub.18H.sub.35O.sub.2).sub.x, has been purchased
from Shepherd Chemical; Copper Stearate,
Cu(C.sub.18H.sub.35O.sub.2).sub.x, has been purchased from H. L.
Blachford Ltd and Shelfplus 02 2400.RTM. has been obtain from ALBIS
Chemicals.
Comparative Sample A
[0048] 600 mg of Dercolyte S125 and 25 mg of Manganese Stearate
have been dissolved in 5 mL of DMA. The solution is exposed to air
(20.7% oxygen) in 100 ml sealed flasks provided with a septum that
allowed portions of the inside atmosphere to be drawn for analysis
at different time using a syringe.
[0049] Once filled with air the sealed flask was exposed to light
in a ATLAS Weatherometer (model Ci65A) equipped with a 6500 W Xenon
lamp (continuous light cycle, black panel temperature=63.degree.
C.) for 30 minutes.
[0050] After WOM exposure the sample was kept at 40.degree. C.
without stirring and oxygen concentration measures were carried out
using a Mocon Pac Check 450 head space analyzer over 48 hours
time.
Inventive Sample B
[0051] 600 mg of Dercolyte S125, 25 mg of Manganese Stearate and 30
mg of compound of Example 1 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
Inventive Sample C
[0052] 600 mg of Dercolyte S125, 25 mg of Manganese Stearate and 30
mg of compound of Example 2 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
Inventive Sample D
[0053] 600 mg of Dercolyte S125, 25 mg of Manganese Stearate and 30
mg of compound of Example 3 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
[0054] The results in terms of O.sub.2%/Time are reported in Table
1.
[0055] Oxygen % left in the sealed flask at different time. Samples
have been stored at 40.degree. C. Oxygen measurement was carried
out when samples were at room temperature.
TABLE-US-00005 TABLE 1 Time 0 3 6 24 27 30 48 % O.sub.2 Hours Hours
Hours Hours Hours Hours Hours Comparative 19.9 18.6 18.4 17.3 17.5
17.3 16.1 Sample A Inventive Sample B 20.0 16.8 15.9 10.7 10.2 9.3
9.2 Inventive Sample C 19.9 14.9 13.8 9.1 8.5 8.1 7.9 Inventive
Sample D 19.9 15.4 14.6 10.2 9.8 9.0 8.7
Comparative Sample E
[0056] 600 mg of Dercolyte S125 and 25 mg of Copper Stearate have
been dissolved in 5 mL of DMA. The sample has been processed as
described in Comparative Sample A.
Inventive Sample F
[0057] 600 mg of Dercolyte S125, 25 mg of Copper Stearate and 30 mg
of compound of Example 1 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
Inventive Sample G
[0058] 600 mg of Dercolyte S125, 25 mg of Copper Stearate and 30 mg
of compound of Example 2 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
Inventive Sample H
[0059] 600 mg of Dercolyte S125, 25 mg of Copper Stearate and 30 mg
of compound of Example 3 have been dissolved in 5 ml of DMA. The
sample has been processed as described in Comparative Sample A.
[0060] The results in terms of O.sub.2%/Time are reported in Table
2.
[0061] Oxygen % left in the sealed flask at different time. Samples
have been stored at 40.degree. C. Oxygen measurement was carried
out when samples were at room temperature.
TABLE-US-00006 TABLE 2 Time 0 3 6 24 27 30 48 % O.sub.2 Hours Hours
Hours Hours Hours Hours Hours Comparative 19.8 18.6 18.6 18.2 18.2
18.2 18.1 Sample E Inventive Sample F 19.7 16.0 15.0 13.3 13.1 13.6
13.3 Inventive Sample G 19.7 13.5 13.2 12.0 11.9 11.9 12.3
Inventive Sample H 19.7 14.8 14.7 14.4 14.4 14.6 14.6
Oxygen Scavenger Activity in LDPE Film
Comparative Sample 1
[0062] Shelfplus O.sub.2 2400.RTM. was mixed with low density
polyethylene, Riblene.RTM. so that the final Iron concentration was
7.0% by weight. Compounds were prepared with an OMC pilot double
screw extruder (model EBV 19/25, with a 19 mm screw diameter and
1:25 ratio), and 50 micron-thick films were prepared using Collin
Cast Flat-die Extruder model 30.times.25 L/D (30 mm screw diameter,
1:25 diameter/length ratio).
Comparative Sample 2
[0063] 2.0% of polyterpenic resin Dercolyte.RTM. S125 and 0.2% of
Manganese Stearate were mixed with low density polyethylene,
Riblene.RTM.. Compounds and Film were prepared as described in
Comparative Sample 1.
Comparative Sample 3
[0064] 2.0% of polyterpenic resin Dercolyte.RTM. S125 was mixed
with low density polyethylene, Riblenee. Compounds and Film were
prepared as described in Comparative Sample 1.
Inventive Sample 4
[0065] 2.0% of polyterpenic resin Dercolyte.RTM. S125, 0.2% of
Manganese Stearate and 0.2% of compound of Example 1 were mixed
with low density polyethylene, Riblene.RTM.. Compounds and Film
were prepared as described in Comparative Sample 1.
Inventive Sample 5
[0066] 2.0% of polyterpenic resin Dercolyte.RTM. S125, 0.2% of
Manganese Stearate and 0.2% of compound of Example 2 were mixed
with low density polyethylene, Riblene.RTM.. Compounds and Film
were prepared as described in Comparative Sample 1.
Inventive Sample 6
[0067] 2.0% of polyterpenic resin Dercolyte.RTM. S125, 0.2% of
Manganese Stearate and 0.2% of compound of Example 3 were mixed
with low density polyethylene, Riblene.RTM.. Compounds and Film
were prepared as described in Comparative Sample 1.
[0068] Several aliquots of film for each samples were then exposed
in an ATLAS Weatherometer (model Ci65A) equipped with a 6500 W
Xenon lamp (continuous light cycle, black panel
temperature=63.degree. C.) for 5 minutes
[0069] Film samples were then exposed to air (20.7% O.sub.2) in 500
ml sealed flasks provided with a septum that allowed portions of
the inside atmosphere to be drawn for analysis at several intervals
using a syringe. Oxygen concentration measures were carried out
using a Mocon Pac Check 450 head space analyzer over 28 days. The
actual iron concentration in Comparative Sample 1 was measured by
ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer,
Perkin Elmer Optima Series 4200DV). The results in terms of ml
O.sub.2/g of active scavenger are given in Table 3.
[0070] Averaged oxygen scavenger activity (ml O.sub.2/g Scavenger)
for six different LDPE film measured after 28 days. In case of
Comparative Sample 1*: g of active scavenger=g of iron in the film;
in all the other cases: g. of active scavenger=g. of Dercolyte+g.
of metal complex+g. of photosensitizer molecule.
TABLE-US-00007 TABLE 3 ml O.sub.2/g Scavenger After 28 Days
Comparative Sample 1* 36 Comparative Sample 2 49 Comparative Sample
3 No O.sub.2 uptake detectable Inventive Sample 4 84 Inventive
Sample 5 78 Inventive Sample 6 69
[0071] Table 3 clearly shows that oxygen scavenger reactivity of
Inventive Samples from 4, 5 and 6 is greater than the oxygen
scavenger activity of Comparative Sample from 1 to 3.
[0072] The amount of oxygen adsorbed by the test samples was
determined from the change in the oxygen concentration in the head
space of a sealed glass container. The test container had a
headspace volume of about 500 ml and contained atmospheric air so
that about 100 ml of oxygen were available for reaction with the
iron particles. In all the examples oxygen scavenger component
percentages are in weight percents based on total weight of the
film composition.
Description of Oxygen Uptake Method:
[0073] Film thickness is measured and 4.0 grams of film are
weighted. The extruded film is folded and placed in a clean 500 ml
sealed glass container. A vial containing 15 ml of deionized water
is added to produce 100% relative humidity inside the glass
container (only for Comparative Sample 1).
[0074] The oxygen content in the ambient air on day 0 (i.e. equal
to the initial oxygen content in the sealed glass container) is
tested and recorded using a Mocon Oxygen Analyzer.
[0075] The glass containers with test films and water vials are
stored at 22.degree. C. (generally, room temperature) for 28
days.
[0076] The oxygen content in the sealed glass containers using a
Mocon Oxygen Analyzer on day 28 are tested and recorded.
[0077] Based on the measured oxygen concentration that is left in
the sealed glass container the volume of oxygen absorbed per gram
of Scavenger has been calculated using the formula:
Oxygen absorbed (ml/g)={(% O.sub.2).sub.i-(%
O.sub.2).sub.f}*0.01*V.sub.j/(W.sub.F*W.sub.S/W.sub.B)
where: [0078] (% O.sub.2).sub.i Initial oxygen concentration in the
sealed glass container (%) [0079] (% O.sub.2).sub.f Oxygen
concentration in the sealed glass container at day of test (%)
[0080] 0.01: Conversion factor [0081] V.sub.j: Free air volume of
the sealed glass container (ml) (total volume of the sealed glass
container less space occupied by vial and film, typically 440 ml)
[0082] W.sub.F: Weight of film placed into the glass container
(typically 4.0 g) [0083] W.sub.S: Weight of Oxygen Scavenger used
to make blend (g) [0084] W.sub.B: Total weight of blend (g)
* * * * *