Note: Descriptions are shown in the official language in which they were submitted.
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Polymer blend containing polyolefins
Interest is increasingly being shown in materials which are very comfortable
to wear,
i.e. materials which exhibit elevated water vapour permeability. 'This
elevated water
vapour permeability is a property necessary to many areas of use, such as
clothing
and sanitary products (e.g. nappies) but also in the building sector for roof
lining
membranes, allowing the achievement of a high level of functional efficiency.
High water vapour permeability levels are exhibited by various materials, e.g.
Gore-
Tex~ (specially stretched polytetrafluoroethylene films made by Gore Ind.) or
Sympatex~ (aliphatic-aromatic polyether esters made by Akzo) (c.f. Rompps
Chemie-Lexikon, Vol. 6, p. 5000, Thieme Verlag Stuttgart, 9th Edition 1992).
Both
materials exhibit the disadvantage of requiring special production methods and
in
addition the raw materials are very expensive.
The object therefore arose of achieving high water vapour permeability levels
with
materials which are easy to produce and exhibit the mechanical properties
required
for the various applications.
It was surprisingly found that blends of aliphatic or partially aromatic
polyesters,
thermoplastic aliphatic or partially aromatic polyester urethanes, aliphatic
or
aliphatic-aromatic polyester carbonates, aliphatic polyester amides and/or
polyether
ester amides with polyolefins, optionally modified polyolefins, together
optionally
with fillers and reinforcing materials, exhibit very high levels of water
vapour
permeability. Films made from the blend according to the invention
additionally
exhibit the property that they may be drawn out very thinly, in contrast to
pure filled
polyolefin films.
The invention relates to mixtures containing
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1 ) 5 to 95, preferably 10 to $0, in particular 1 S to 60 parts by weight of
at least
one polymer selected from the group consisting of aliphatic or partially
aromatic polyesters, thermoplastic aliphatic or partially aromatic polyester
urethanes, aliphatic or aliphatic-aromatic polyester carbonates, aliphatic or
partially aromatic polyester amides and/or polyether ester amides,
2) 5 to 70, preferably 7 to 60, in particular 10 to 50 parts by weight of
polyolefins,
3) 0 to 25, preferably 0 to 20, in particular 0 to 15 parts by weight of
modified
polyolefins and
4) 0 to 80, preferably 0 to 70, in particular 5 to 60 parts by weight of
fillers and
reinforcing materials,
wherein the sum of 1), 2), 3) and 4) is 100.
Component 1)
The polymers according to component 1 ) are selected from at least one polymer
from the group consisting of aliphatic or partially aromatic polyesters,
thermoplastic
aliphatic or partially aromatic polyester urethanes, aliphatic or aliphatic-
aromatic
polyester carbonates, aliphatic or partially aromatic polyester amides and
polyether
ester amides.
The following polymers are suitable:
Aliphatic or partially aromatic polyesters from
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A) aliphatic bifunctional alcohols, preferably linear CZ to C,o, preferably Cz
- C6
dialcohols such as, for example, ethanediol, propanediol, butanediol,
hexanediol or particularly preferably butanediol, and/or optionally
cycloaliphatic bifunctional alcohols, preferably with 5 or 6 C atoms in the
cycloaliphatic ring, such as for example cyclohexanedimethanol, and/or,
partially or completely replacing the diols, monomeric or oligomeric polyols
based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers
thereof with molecular weights of up to 8000, preferably up to 4000, and/or
optionally small amounts of branched bifunctional alcohols, preferably C3 -
C,, alkyl diols, such as for example neopentyl glycol, and additionally
optionally small amounts of more highly functional alcohols such as for
example 1,2,3-propanetriol or trimethylolpropane, as well as from aliphatic
bifunctional acids, preferably Cz - C,z alkyl dicarboxylic acids, such as for
example and preferably succinic acid, adipic acid, and/or optionally aromatic
bifunctional acids, such as for example terephthalic acid, isophthalic acid,
naphthalene dicarboxylic acid, and additionally optionally small amounts of
more highly functional acids such as for example trimellitic acid or
B) from acid- and alcohol-functionalised units, preferably with 2 to 12 C
atoms
in the alkyl chain, for example hydroxybutyric acid, hydroxyvaleric acid,
lactic acid or derivatives thereof, for example E-caprolactone or dilactide,
or a mixture and/or copolymer of A and B,
wherein the aromatic acids preferably constitute a fraction of no more than
80, in
particular 50 wt.%, relative to all the acids;
aliphatic or partially aromatic polyester urethanes from
C) aliphatic bifunctional alcohols, preferably linear CZ to C,o, preferably Cz
- C6
dialcohols such as, for example, ethanediol, propanediol, butanediol,
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hexanediol, particularly preferably butanediol, and/or optionally
cycloaliphatic bifunctional alcohols, preferably with a CS or C6
cycloaliphatic
ring, such as for example cyclohexanedimethanol, and/or, partially or
completely replacing the diols, monomeric or oligomeric polyols based on
ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof
with molecular weights of up to 4000, preferably up to 1000, and/or
optionally small amounts of branched bifunctional alcohols, preferably C3 -
C,Z alkyl diols, such as for example neopentyl glycol, and additionally
optionally small amounts of more highly functional alcohols, preferably C3 -
C,Z alkyl polyols, such as for example 1,2,3-propanetriol or
trimethylolpropane, as well as from aliphatic bifunctional acids, preferably
CZ - C,z alkyl dicarboxylic acids, such as for example and preferably succinic
acid, adipic acid, and/or optionally aromatic bifunctional acids, such as for
example terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid,
and additionally optionally small amounts of more highly functional acids
such as for example trimellitic acid or
D) from acid- and alcohol-functionalised units, preferably with 2 to 12 C
atoms,
for example hydroxybutyric acid, hydroxyvaleric acid, lactic acid or
derivatives thereof, for example s-caprolactone or dilactide,
or a mixture and/or copolymer of C and D,
wherein the aromatic acids preferably constitute a fraction of no more than
80, in
particular 50 wt.%, relative to all the acids;
E) from the reaction product of C and/or D with aliphatic and/or
cycloaliphatic
bifunctional and additionally optionally more highly functional isocyanates,
with preferably 1 to 12 C atoms or 5 to 8 C atoms in the case of
p0 cycloaliphatic isocyanates, e.g. tetramethylene diisocyanate, hexamethylene
diisocyanate, isophorone diisocyanate, optionally additionally with linear
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and/or branched and/or cycloaliphatic bifunctional and/or more highly
functional alcohols, preferably C3 - C,Z alkyl di- or polyols or 5 to 8 C
atoms ,
in the case of cycloaliphatic alcohols, e.g. ethanediol, hexanediol,
butanediol,
cyclohexane-dimethanol, and/or optionally additionally with linear and/or
branched and/or cycloaliphatic bifunctional and/or more highly functional
amines and/or amino alcohols with preferably 2 to 12 C atoms in the alkyl
chain, e.g. ethylene diamine or aminoethanol, and/or optionally further
modified amines or alcohols such as for example
ethylenediaminoethanesulfonic acid, as a free acid or salt,
wherein the ester fraction C) and/or D) preferably amounts to at least 40, in
particular 75 wt.%, relative to the sum of C), D) and E);
aliphatic or aliphatic-aromatic polyester carbonates from
F) aliphatic bifunctional alcohols, preferably linear CZ to C,°
dialcohols such as,
for example, ethanediol, butanediol, hexanediol or particularly preferably
butanediol, andlor optionally cycloaliphatic bifunctional alcohols, preferably
with 5 to 8 C atoms in the cycloaliphatic ring, such as for example
cyclohexanedimethanol, and/or, partially or completely replacing the diols,
monomeric or oligomeric polyols based on ethylene glycol, propylene
glycol, tetrahydrofuran or copolymers thereof with molecular weights of up
to 8000, preferably up to 4000, and/or optionally small amounts of branched
bifunctional alcohols, preferably CZ - C,z alkyldicarboxylic acids, such as
for
example neopentyl glycol, and additionally optionally small amounts of
more highly functional alcohols such as for example 1,2,3-propanetriol,
trimethylolpropane, as well as from aliphatic bifunctional acids, such as for
example and preferably succinic acid, adipic acid and/or optionally aromatic
bifunctional acids such as for example terephthalic acid, isophthalic acid,
naphthalene dicarboxylic acid and additionally optionally small amounts of
more highly functional acids such as for example trimellitic acid or
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G) from acid- and alcohol-functionalised units, preferably with 2 to 12 C
atoms
in the alkyl chain, for example hydroxybutyric acid, hydroxyvaleric acid,
lactic acid or derivatives thereof, for example s-caprolactone or dilactide,
or a mixture and/or copolymer of F and G,
wherein the aromatic acids preferably constitute a fraction of no more than SO
wt.%,
relative to all the acids;
H) a carbonate fraction, which is produced from aromatic bifunctional phenols,
preferably bisphenol A and carbonate donors, for example phosgene,
or
a carbonate fraction, which is produced from aliphatic carbonic acid esters or
derivatives thereof, such as for example chloroformic acid esters or aliphatic
carboxylic acids or derivatives thereof such as for example salts and
carbonate donors, for example phosgene, wherein
the ester fraction F) and/or G) preferably amounts to at least 40, in
particular 70
wt.%, relative to the sum of F), G) and H);
aliphatic or partially aromatic polyester amides or polyether ester amides
from
I) aliphatic bifunctional alcohols, preferably linear CZ to C,°,
preferably Cz - C6
dialcohols such as, for example, ethanediol, propanediol, butanediol,
hexanediol, particularly preferably butanediol, and/or optionally
cycloaliphatic bifunctional alcohols, preferably with 5 to 8 C atoms, such as
for example cyclohexanedimethanol, and/or, partially or completely
replacing the diols, monomeric or oligomeric polyols based on ethylene
glycol, propylene glycol, tetrahydrofuran or copolymers thereof with
molecular weights of up to 10,000, preferably up to 8000, in particular up to
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5000, and/or optionally small amounts of branched bifunctional alcohols,
preferably C3 - C,z alkyl diols, such as for example neopentyl glycol, and
additionally optionally small amounts of more highly functional alcohols
such as for example 1,2,3-propanetriol, trimethylolpropane, as well as from
aliphatic bifunctional acids, preferably with 2 to 12 C atoms in the alkyl
chain, such as for example and preferably succinic acid, adipic acid, and/or
optionally aromatic bifunctional acids such as for example terephthalic acid,
isophthalic acid, naphthalene dicarboxylic acid and additionally optionally
small amounts of more highly functional acids such as for example trimellitic
acid or
K) from acid- and alcohol-functionalised units, preferably with 2 to 12 C
atoms
in the carbon chain, for example hydroxybutyric acid, hydroxyvaleric acid,
lactic acid or derivatives thereof, for example s-caprolactone or dilactide,
or a mixture and/or a copolymer of I) and K),
wherein the aromatic acids preferably constitute a fraction of no more than
80, in
particular 50 wt.%, relative to all the acids;
L) an amide fraction of aliphatic and/or cycloaliphatic bifunctional and/or
optionally small amounts of branched bifunctional amines, linear aliphatic
di-CZ - C,o alkyl amines being preferred, and additionally optionally small
amounts of more highly functional amines, preferably
hexamethylenediamine, isophorone diamine and particularly preferably
hexamethylenediamine, as well as from linear and/or cycloaliphatic
bifunctional acids, preferably with 2 to 12 C atoms in the alkyl chain or CS
or
C~ ring in the case of cycloaliphatic acids, preferably adipic acid, and/or
optionally small amounts of branched bifunctional and/or optionally
aromatic bifunctional acids such as for example terephthalic acid, isophthalic
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acid, naphthalene dicarboxylic acid and additionally optionally small
amounts of more highly functional acids, preferably with 2 to 10 C atoms, or
M) from an amide fraction of acid- and amine-functionalised units, preferably
with 4 to 20 C atoms in the cycloaliphatic chain, preferably w-laurolactam, E-
caprolactam, particularly preferably E-caprolactam,
or a mixture of L) and M) as amide fraction, wherein
the ester fraction I) and/or K) preferably amounts to at least 30 wt.%,
relative to the
sum of I), K), L) and M), the proportion by weight of the ester structures
preferably
amounting to 30 to 80 wt.% and the proportion of the amide structures
preferably
amounting to 70 to 20 wt.%.
Hydroxyl- or acid-terminated polyester with molecular weights (weight average)
of
from 300 to 10,000 may likewise be used as ester-forming component.
All the acids may also be used in the form of derivatives such as for example
acid
chlorides or esters, both as monorneric and oligomeric esters.
Polyether ester amides are particularly preferred which exhibit a random
arrangement of ester and amide segments and wherein the alcohol component
consists of monomeric and oligomeric diols and the content of oligomeric diol,
relative to the total content of alcohol component, amounts in general to 10
to 99,
preferably 15 to 80 mol%.
The polyether ester amides are composed in particular of the following
monomers:
oligomeric polyols consisting of polyethylene glycols, polypropylene glycols,
polyglycols, of random or block-type structure, from mixtures of ethylene
oxide or
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propylene oxide or polytetrahydrofuranswith molecular weights (weight average)
of
between 100 and 10,000 and
monomeric diols, preferably Cz - C,2 alkyl diols, in particularly Cz - C6
alkyl diols,
for example ethylene glycol, 1,4-butanediol, 1,3-propanediol, 1,6-hexanediol,
and at least one monomer selected from the group consisting of
dicarboxylic acids, preferably Cz - C,z, particularly preferably CZ - C6 alkyl
dicarboxylic acids, for example oxalic acid, succinic acid, adipic acid, also
in the
form of the respective ethers thereof (methyl, ethyl etc.)
Cz - C,Z alkylhydroxycarboxylic acids and lactones such as caprolactone inter
alia
amino alcohols with 2 to 12 carbon atoms in the alkyl chain, for example
ethanolamine, propanolamine
cyclic lactams with 5 to 12, preferably 6 to 11, C atoms, such as s-
caprolactam or
laurolactam etc.
c~-aminocarboxylic acids with 6 to 12 C atoms in the alkyl chain such as
aminocaproic acid etc.
mixtures (1:1 salts) of CZ - C,z alkyl dicarboxylic acids, for example adipic
acid,
succinic acid and Cz - C,2 alkyl diamines, for example hexamethylenediamine,
diaminobutane.
Likewise, both hydroxyl- or acid-terminated polyesters with molecular weights
of
between 300 and 10,000 may be used as ester-forming component.
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The proportion of the ether and ester fractions in the polymer amounts in
general to
to 85 wt.%, relative to the total polymer.
The polyether ester amides according to the invention in general have an
average
5 molecular weight (Mw determined by gel chromatography in cresol relative to
a
polystyrene standard) of from 10,000 to 300,000, preferably 15,000 to 150,000,
in
particular 15,000 to 100,000.
The synthesis of the polyester amides or polyether ester amides according to
the
invention may be performed both by the "polyamide method", entailing
stoichiometric mixing of the starting components optionally with the addition
of
water and then removal of water from the reaction mixture, and by the
"polyester
method", entailing stoichiometric mixing of the starting components together
with
the addition of an excess of diol with esterification of the acid groups and
subsequent transesterification or transamidation of these esters. In this
second
instance, not only the water but also the excess diol is distilled off again.
Synthesis
by the above-described "polyester method" is preferred.
Polycondensation may additionally be accelerated by the use of known
catalysts.
Both the known phosphorus compounds which accelerate polyamide synthesis and
acidic or organometallic catalysts for esterification as well as combinations
of the
two may be used to accelerate polycondensation.
Furthermore, polycondensation to produce polyester amides may be influenced by
the use of lysine, lysine derivatives or other amidically branching products
such as
for example aminoethylaminoethanol, which both accelerate condensation and
result
in branched products (see for example DE-3 831 709).
The production of polyesters, polyester carbonates and polyester urethanes is
3() generally known or is performed in a manner similar to known methods (c.f.
for
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example EP-A-304 787, WO 95/12629, WO 93/13154, EP-A-682 054, EP-A-593
975).
The polyesters, polyester urethanes, polyester carbonates, polyester amides
and
polyether ester amides according to the invention may additionally contain 0.1
to
5 wt.%, preferably 0.1 to 1 wt.%, of branching agents (c.f. also description
of
polymers). These branching agents may for example be trifunctional alcohols
such
as trimethylolpropane or glycerol, tetrafunctional alcohols such as
pentaerythritol,
trifunctional carboxylic acids such as citric acid.
The polymers cited as component 1 ) have as a rule a molecular weight of at
least
10,000 g/mol, preferably 10,000 to 100,000, in particular 15,000 to 60,000
g/mol
and generally have a random distribution of starting substances in the
polymer.
When the polymer is synthesised in the manner typical of polyurethanes,
optionally
from C) and D) as well as from E), completely random distribution of the
monomeric units cannot always be expected.
Component 2)
Polyolefins suitable according to the invention are polymers of aliphatically
unsaturated hydrocarbons, such as for example ethylene, propylene, butylene or
isobutylene, which are obtained by conventional methods, e.g. free radical
polymerisation or by means of metallocene catalysis. The polyolefins as a rule
have
average weight average molecular weights M W (measured by gel chromatographic
methods) of from 5000 to 3,000,000. Both high density polyolefin and low
density
polyolefin, e.g. LDPE, LLDPE, MDPE, may be used.
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The polyolefins are generally known and are described for example in Ullman's
Encyclopedia of industrial chemistry, Vol. A21, pp. 487-577, 5th compl. rev.
ed.
1992, VCH Verlag, Weinheim.
Component 3)
Modified polyolefins are polyolefins which may be obtained either by grafting
of the
above-mentioned polyolefms or by copolymerisation of the monomers mentioned
under component 2), preferably ethylene and/or propylene, with other monomers,
preferably vinyl monomers, with reactive groups, e.g. anhydride, amino, acid,
epoxy, ester or keto groups or salts of carboxylic acids. Preferred
copolymerisable
monomers are acrylic acid and its alkyl esters of mono- and/or di-C, - C,Z-,
preferably C2 - C6-alkanols, together with malefic anhydride.
The modified polyolefins used in the present invention are preferably of the
following composition:
a) 40 to 99.9, preferably 88 to 99.9 wt.%, of at least one or more a-olefins
with
2 to 8 C atoms,
b) 0 to 50 wt.% of a dime,
c) 0 to 45 wt.% of a primary or secondary C, - C,2 alkyl ester of acrylic acid
or
methacrylic acid or mixtures of such esters,
d) 0 to 45 wt.% of an olefinically unsaturated mono- or dicarboxylic acid,
e.g.
malefic anhydride, which may also be present partially or completely as a salt
and/or a functional derivative of such an acid,
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e) 0 to 40 wt.% of an epoxy group-containing monomer, e.g. glycidyl
methacrylate or glycidyl acrylate,
f) 0 to 75 wt.% of a vinyl ester, e.g. vinyl acetate or saponified products
thereof
(vinyl alcohols)
wherein at least one of the components b, c, d, a and f is included.
Grafted or copolymerised ethylene/acrylic acid (t-alkyl) esters,
ethylene/glycidyl
acrylate (or allylglycidic ether)/acrylic acid (t-alkyl) esters,
ethylene/acrylic acid
(ester)/maleic anhydride or ethylene/maleic anhydride are particularly
preferred.
The molecular weight (weight average) of the modified polyolefins amounts in
general to 5000 to 3,000,000, preferably 10,000 to 1,000,000 (measured by gel
chromatographic methods).
The modified polyolefins are known or may be produced by known methods (e.g.
EP-A-77 415).
Component 4)
Inorganic materials are generally used as fillers and reinforcing agents.
These are
fibrous reinforcing materials such as glass and carbon fibres and mineral
fillers, e.g.
talc, mica, chalk, kaolin, wollastonite, gypsum, quartz, dolomite, silicates.
Mineral
fillers are preferred, in particular chalk.
The fillers and reinforcing materials may also be surface-treated.
Glass fibres generally have a fibre diameter of between 8 and 14 pm and may be
used in the form of continuous filaments or cut or ground glass fibres,
wherein the
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fibres may be provided with a suitable sizing system and a coupling agent or
coupling agent system on the basis of silane.
The mixtures according to the invention may additionally contain conventional
S additives such as UV stabilisers, antioxidants, pigments, dyestuffs,
nucleating
agents, crystallisation accelerators or retarders, flow auxiliaries,
lubricants, mould
release agents and flame retardants.
The mixtures according to the invention and optionally other additives may be
produced by mixing the respective constituents in a known way and melt-
compounding or melt-extruding them at conventional temperatures, e.g.
150°C to
300°C, in conventional units such as internal mixers, extruders, twin-
screw
extruders.
The mixture according to the invention may be used for injection moulding, in
fibre
or film form or in the nonwoven sector (spun-bond or melt-blown).
Use in film form is preferred. The films may be used alone or as a composite
component in conjunction with other nonwovens, woven fabrics, knitted fabrics
or
other films.
Preferred areas of use are: sanitary products (e.g. nappies, sanitary towels,
incontinence pads for adults); packaging in general, clothing, e.g. also in
the medical
field, building, e.g. roof lining membranes.
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Examples
Example 1
40 wt.% of a polyester amide of adipic acid, butanediol and caprolactam with
an
ester/amide ratio of 40/60, randomly copolycondensed (with a relative solution
viscosity of 2.5, measured using a 1 wt.% solution in meta-cresol at
20°C) are
compounded with 40 wt.% of a finely divided chalk produced by Omya (Cologne,
Germany (Hydrocarb 95T)) and 20 wt.% Lupolen~, an LDPE produced by BASF
(Ludwigshafen, Germany) in a twin-screw extruder (ZSK) at 170°C. The
blend may
be pelletised without difficulty.
Subsequent processing in a blown film installation results in white-coloured
films
with a thickness of 10 pm. The water permeability of these films in accordance
with
the DIN standard using the Mocon method amounts to 770 g/mz'd.
Example 2
30 wt.% of a polyether ester amide of AH salt, adipic acid, diethylene glycol
and
polyethylene glycol 400 with an ester/amide ratio of 70/30 are compounded with
40 wt.% of a finely divided chalk produced by Omya (Cologne, Germany
(Hydrocarb 95T)) and 30 wt.% Lupolen~, an LLDPE produced by BASF,
Ludwigshafen, Germany, in a twin-screw extruder (ZSK) at 180°C. The
blend may
be pelletised without difficulty.
Subsequent processing in a blown film installation results in white-coloured
films
with a thickness of 8 pm.
s0 The water permeability of these films in accordance with the DIN standard
using the
Mocon method amounts to 1030 g/m''d.
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Production of the polyether ester amide in Example 2:
710 g AH salt, 253 g adipic acid, 184 g diethylene glycol and 1380 g
polyethylene
glycol 400 are mixed together with titanium(IV) isopropylate as catalyst and
heated
under nitrogen to 240°C. When the water has been distilled off, the
pressure is
reduced in stages to I mbar. After 3 hours of polycondensation, a colourless,
high
molecular weight material is obtained (relative viscosity of 3.2 measured in 1
wt.%
solution in m-cresol at 25°C) with a melting point of 186°C.
Example 3
35 wt.% of a polyether ester amide of AH salt, adipic acid, diethylene glycol
and
polyethylene glycol 1000 with an ester/amide ratio of 60/40 are compounded
with
30 wt.% of the above-mentioned finely divided chalk produced by Omya, 30 wt.%
Lupolen, an LLDPE produced by BASF and 5 wt.% of an ethylene/acrylic acid
ester
copolymer (Lucalen~, BASF, Ludwigshafen, Germany) using a twin-screw extruder
(ZSK) at 180°C. The blend may be pelletised without difficulty.
Subsequent processing in a blown film installation results in white-coloured
films
with a thickness of 10 pm. The water permeability of these films in accordance
with
the DIN standard using the Mocon method amounts to 9230 g/mz'd.
