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Nano-layer Effects in Blown Barrier Films
Henry G. Schirmer, BBS Corporation, Spartanburg, SC
Randy Jester, TOPAS Advanced Polymers Inc., Florence, KY
Gene D. Medlock, Kuraray America, Inc. – EVAL BU, Pasadena, TX
Tom Schell, Curwood, Inc., Oshkosh, WI
Abstract
Coextruded blown barrier films consisting of micro-layers
and increasing numbers of nano-layers were made for the
purpose of determining if they could be used to enhance
barrier properties. Nano-layers of EVOH were alternated
with moisture barrier materials in this study. Film
processing and properties are described as the number of
nano-layers was increased.
Introduction
At the 2009 Polyolefin’s Conference a paper about nano-
layers in blown film was given Ref 14). These films were
produced using the newly invented device called a Layer
Sequence Repeater (LSR). Nano-layers made from two
brittle resins produced films that were less brittle. The two
brittle materials examined were EVOH, a water sensitive
O2 barrier and COC a moisture barrier. In that study there
were hints that nano-layers may have improved the O2
barrier of EVOH by itself but especially under the
punishing Gelbo flex abuse conditions and also hints that
Perhaps nano-layers may have enhanced the moisture
barrier for COC.
At the same conference EDI gave a paper also showing
increased barrier film performance as the number of
alternating nano-layers of EVOH within a polypropylene
based film structure were increased using a layer
multiplier (LM). So this study was made to see if films
made using the LSR might produce similar results.
Both the LM and LSR are capable of producing many
nano-layers. However, the LM is used only with flat die
systems and the LSR is used primarily with blown film
systems. The names given to the two devices are
descriptive in how they differ fundamentally to achieve
similar results. But we will talk about the LSR details only
at some future date because of patent reasons.
This paper then is focused on determining if alternating
nano-layers of EVOH with a moisture barrier material can
enhance the wet O2 barrier performance of EVOH.
Polypropylene is a fairly good moisture barrier. So a
polypropylene based adhesive resin for EVOH was
chosen. COC is also a very good moisture barrier but is
not a good adhesive resin for EVOH. In spite of its poor
adhesive qualities, COC was also evaluated. Both of these
moisture barrier materials were put into EVOH barrier
films made from a Modular Disk Blown Film Die with an
added LSR. Reported here are the processing and property
results as the number of layers was increased from 25 to
75 and then finally to 50 and 150 using blown film
samples in double wound (D/W) form.
Ethylene vinyl alcohol (EVOH L-171) made by Kuraray
America and Cyclic Olefin Copolymer (TOPAS® COC
8007F-04) made by TOPAS Advanced Polymers and QF
551 made by Mitsui Petrochemicals were the material
grades chosen.
QF 551 is a standard adhesive resin to adhere both EVOH
and Nylon to polypropylene. EVOH (L-171 at 27 mol %
ethylene) is a crystalline brittle moisture sensitive
copolymer with a Tg at 60C and COC (8007F-04) is an
amorphous brittle copolymer with a Tg at 78C. EVOH is a
material with high oxygen barrier properties useful in food
packaging films and COC is a high moisture barrier
material useful in medical and pharmaceutical packaging.
Discussion
Definition of terms The Modular Disk Die has
produced films containing 25 and more micro-layers
independently of the LSR. While it is generally true that as
the number of micro-layers increases, the individual layer
thickness decreases for a given total film thickness, the
thickness of each of the structural micro-layers are
generally all in the same order of magnitude. However,
some these micro-layers may contain the same material to
make what appear to be fewer and thicker micro-layers.
The reason for doing this might be to simply gain
increased output.
The Layer Sequence Repeater (LSR) operates as an
independent unit within a Modular Disk Die and inserts
nano-layer bundles within this matrix of micro-layers.
These are truly an order of magnitude thinner than the
surrounding micro-layers. This definition of nano-layers
will be used here to differentiate nano-layers from micro-
layers and the difference will become very apparent from
the microphotographs shown in this paper.
2
Picture 1 shows a 25 micro-layer barrier film being made
from an 18” 25 layer Modular Disk blown film production
die. Picture 2 shows the internal micro-layer structure. In
this case the 25 micro-layers were combined to make a
pseudo-7 layer Nylon/ EVOH/ Poly barrier film that is the
standard barrier film for the industry and is an example of
creating thicker and fewer micro-layers for the sake of
increased output. This of course is the opposite end of the
nano-layer spectrum but is noteworthy to show that the
same material can be used in micro-layers as it can in
nano-layers to make fewer apparent layers. In some cases
doing this alone will alter the films physical properties
because of different melt shear conditions within.
Picture 1 - 18” 25 micro-layer Modular Disk Die
functioning to make 7 apparent micro-layer barrier films
Picture 2 Standard Barrier Film thicknesses front and back
at 2.55 mil each
While the above 7 layer micro-layer barrier film was made
from a 2x version of the lab dies, the coextruded nano-
layer films reported here were made using a 1x Layer
Sequence Repeater (LSR) inserted within the module of a
1x laboratory Modular Disk Die. These films show an
entirely different layer structure from the micro-layer
films.
A bundle of 75 nano-layers within a matrix of 8 micro-
layers; 4 on each side is shown in Picture 3. Note that each
of the 3 micro-layers on both sides used the same
polyethylene to make what appears to be a single layer.
Here you can see that nano-layers are truly a magnitude
thinner than micro-layers.
Picture 3 75 Nano-layers in a matrix of 8 Micro-layers
Sample 12-2 Total Thickness = 3.2 mil
Picture 4 shows that blowing 75 nano + 8 micro-layer
films in the lab are very similar to blowing single layer
films in production. However, like any other coextruded
film there can be a myriad of coextrusion problems to
overcome and there were some new ones we encountered
in this study either because of extrusion rate or materials
used.
Picture 4 - Laboratory 4” Upward Blown Film Line
Used to make Sample 12-2
FRONT SIDE PE+adhesive Nylon/EVOH/Nylon PE + adhesive PE + adhesive Nylon/EVOH/Nylon PE + adhesive BACK SIDE
3 micro-layers PE 1 layer Vistamaxx 75 nano-layers of PP/Vistamaxx 1 Layer Vistamaxx 3 micro-layers PE
3
To sum it up, nano-layer thickness is defined not by actual
thickness but by relative thickness when compared to the
surrounding micro-layer matrix. Further, nano-layers and
micro-layers both can use the same materials but nano-
layers will certainly appear as a bundle of thinner layers
within the micro-layer matrix.
The structural diagram shown in Picture 5 shows the
progression we are making from standard 7 layer barrier
film structures of today to the nano-layer barrier film
structures of tomorrow.
Picture 5 Progression to more Layers in Barrier Films
Experimental
2” TEST LINE RUN 11
In order to make the 25 nano + 4 micro-layer test films,
the BBS laboratory small LSR insert was used to make the
25 nano-layers. It occupied the space of only 3 cells. The
test line shown in Picture 6 had also a module for making
the 7-layer control film that was exactly the same size as
the module containing the 25 layer LSR. This made the
test line ideal for preparing and directly comparing 29
layer LSR test films with corresponding 7 micro-layer
control films.
Both the EVOH and COC 25 nano-layer test films (29
layers total) and the micro-layer layer controls (7 layers
total) of Run 11 were made on this line and it is shown in
Picture 6.
The test line had 4 extruders; one 1.25” extruder A and 2
– 0.75” extruders B & C driven by the same drive at an
approximate 60/20/20 ratio. The forth 0.75”extruder D
was driven at 30 rpm while the A extruder was driven at
40 rpm. The calculated layer thickness for a 10-mil test
film was made based on output rates of each extruder and
is shown below along with the comparable control film.
The assumption was that the output rates were
proportional to layer thickness.
Picture 6 – 2” Test Line used to make both 7 micro-layer
and 25 nano + 4 Micro-layer test films
ESTIMATED BARRIER THICKNESS: The relative
layer thickness values shown below were expected with A
extruder (1.25”) delivering 10 lbs/hr @ 40 rpm; B&C
extruders (0.75”) at 44.65 rpm delivering @ 3 lbs/hr each
and extruder D (0.75”) @ 30 rpm delivering 2 lbs/hr.
Test film structure = A / D / {C/B/C/…25 nano-
layers…B/C/B/C} / D / A
TOTAL OUTPUT - LAYER RATIO’S (Basis= 10 mil film)
A= 10 lbs/hr = (10)10/18 = 5.556mil (2 layers)
D= 2 lbs/hr = (10)2/18 = 1.111mil (2 layers)
C= 3 lbs/hr = (10)3/18 = 1.667mil (11 layers)
B= 3 lbs/hr = (10)3/18 = 1.667mil (10 barrier layers)
Lbs/hr=10+2+3+3=18lbs/hr TOTAL = 10.001mil
Calculated barrier/total thickness ratio for test films =
1.667/10 = .167mils/mil
Control film structure = A / D / C / B / C / D / A
TOTAL OUTPUT – LAYER RATIO’S (Basis = 10 mil film))
A= 10 lbs/hr = (10)10/18 = 5.556mil (2 layers)
D= 2 lbs/hr = (10)2/18 = 1.111mil (2 layers)
C= 3 lbs/hr = (10)3/18 = 1.667mil (11 layers)
B= 3 lbs/hr = (10)3/18 = 1.667mil (1 barrier layer)
Lbs/hr = 10+2+3+3= 18 lbs/hr TOTAL = 10.001mil
Calculated barrier/total thickness ratio for Control films =
1.667/10 = .167mils/mil total thickness.
The above calculated thickness estimates, however, give
only support to the actual measurements that were
previously made (Ref 14). Actual optically measured total
nano-layer thickness for each of 2 materials used was
measured in last years paper and will be used here as a
more accurate .211 mils/mil total thickness. See reference
14 “Nano-layers in Blown Film” for details.
7 Layer Standard Barrier
25 Layer Modular Disk Die 7 Layer
Modular Die Structure with Nano-layers
4
POLPROPYLENE/EVOH COMBINATIONS: Right
from the start, coextrusion problems appeared with all of
the 25 nano-layer films. The air-cooling conditions for a
stable bubble were very tight. Too little air gave bubble
pulsing and too much air caused the bubble to do a “snake
dance”. The quality of the film also was poor with respect
to clarity. While haze was expected, these films had a
mottled grainy looking appearance. Perhaps the cross
section SEM photographs below help to visualize the
problem.
Picture 7 Sample 11-9 SEM Micro-photo
PP2004/PP2004/{AD498/ET3803..25 nano-
layers}/PP2004/PP2004 (2.0mil)
Picture 8 Sample 11-10 SEM Micro-photo
PP2004/PP2004/{AD498/L-171..25 nano-
layers}/PP2004/PP2004 (2.0mil)
Picture 9 Sample 11-11 SEM Micro-photo
PP2004/PP2004/{QF551/L-171..25 nano-
layers}/PP2004/PP2004 (2.0mil)
Samples 11-9 through 11-11 all exhibit a chaotic nano-
layer pattern in the cross machine direction. The
underlined nano-layer combinations captioned under each
of the above pictures show that varying the material
combinations did nothing to make the layers more
uniform. The strange behavior seemed related to melt
orientation effects akin to the well-documented strain
hardening of branched polypropylene drawn melts where
thick and thin areas develop during the draw process.
These unstable melt flow conditions continued as both
temperature conditions and EVOH viscosity were lowered
throughout samples 11-12 to 16.
Compare this to Picture 3 where 75 nano-layers of
Vistamaxx/PP2004 in sample 12-2 are rather uniform. The
absence of EVOH in the nano-layers and the substitution
of PP2004 with PE in the outer micro-layers resulted in
stable melt flow conditions. PP2004 is an obsolete
ethylene-propylene copolymer formerly made by
Quantum.
Also compare these results to the results reported from
Run 8 (Ref. 14). Picture 10 shows that sample 8-16 had no
signs of nano-layer chaos using the same AD498/L171
materials in the nano-layer structure but again using
polyethylene in the outer and inner skin micro-layers.
While sample 8-16 had fewer nano-layers, the major
difference here appeared to be with the PE vs. PP outer
micro-layers within the film structure. Clearly all of the PP
film samples from Run 11 were of questionable quality to
submit for testing and were held back.
5
Picture 10 Sample 8-16 Micro-photo
PE 6411/PE 6411/{Admer 498/L-171..21 nano-layers}/PE
6411/PE 6411
The use of the amorphous PP/PE copolymer, Vistamaxx
with PP2004 in the stable 75-nano-layer structure may
have controlled the unstable melt flow effect apparently
caused by PP2004 when used in the outer micro-layers.
Perhaps an extra micro-layer of Vistamaxx in-between the
two as in picture 3 may stabilize nano-layer melt flow
chaos too. However, we felt that further study of this was
beyond the scope of this paper and decided to look at the
alternative COC/EVOH structures. Certainly, we will plan
to return to these unusual material combinations in the
future as the need for polypropylene skin layers may
become necessary for such applications as autoclaving.
So the LSR was flushed with COC where none of the
usual visual haze developed during the transition from
EVOH to COC. Clearly this was an unusual optical
compatibility event and the following 2 structures were
made the next day:
Sample 11-17 PE5563/NF498/{COC/COC..25 nano-
layers}/NF498/PE5563 (2.0mil)
Sample 11-18 PE5563/NF498/{L-171/COC..25 nano-
layers}/NF498 /PE5563 (1.5mil)
EVOH/COC COMBINATIONS: Sample 11-18 was
very clear and was incrementally drawn thinner and
thinner until sample 11-22 at 0.7 mil was made at the
maximum haul off speed. The quality and clarity of all of
the films was excellent but there was no adhesion of COC
to EVOH.
Picture 11 shows the outstanding clarity of the
COC/EVOH film 11-18 compared to the hazy PP/EVOH
counterparts 11-9, 11-10 and 11-11. Look at how well the
wallboards are seen through the backlit sample 11-18
when none can be seen through the 11-9-11 samples.
Picture 11 Clarity of Samples 11-9, 10, 11 and 18
Picture 12 shows the structure of sample 11-18. Clearly
the refractive index of COC and EVOH must be very
close because it is very hard to see the individual nano-
layers even with enhancement. Some layers are seen more
clearly only when they were delaminating during cross
sectioning.
Picture 12 Sample 11-18 Optical Micro-photo (1.6 mil)
PE5563/Admer498/{L-171/COC..25layers}/498/5563
The above samples were then used for wet and dry barrier
testing in spite of the lack of adhesion. Enhancement of
barrier properties in the film would be an indication that
less moisture was absorbed into the EVOH layers and that
the moisture barrier properties of the COC were probably
responsible for this. Notably COC was also an amorphous
material similar to Vistamaxx.
25 nano-layer section some delaminating
layers during cross sectioning
6
4” TEST LINE RUN 12
During run 11 on the 25 nano-layer setup, an 8-extruder
line was being prepared to make films with even a greater
number of nano-layers using 2 larger 1.25” extruders with
variable melt delivery rates to feed the 2 melts to the LSR.
Two triplex extruders were also attached to the die 180
degrees opposed. After the initial start up runs, the line
was fitted with a 4” die, 2 - 4 micro-layer modules each
fed by a triplex extruder and placed on either side of the
75 layer LSR. The experimental films made in Run 11
were essentially to be duplicated on this scaled up
equipment. The upward blown film line is shown in
picture 13.
The 4” die now had 3 separate modules counting the LSR
as a module. The two micro-layer modules were fed from
the 2 triplex extruders that were 180 degrees opposed and
2 single 1.25” extruders fed the LSR nano-layer module.
The quality problems experienced with the polypropylene
series simply became worse and to sum it up briefly we
soon gave up and started trying to make the EVOH/COC
combinations. While these films were not of perfect
quality, we did arrive at combinations that produced film
samples adequate to obtain possible answers from barrier
testing.
Picture 13 - 4” test line used to make 75 nano-layer Films
Sample 12-20 shown in the following micro-photo, picture
14 was similar to the samples collected from Run 11. The
nano-layers were difficult to see and the adhesion between
them was poor. The 75 nano-layer bundle as shown was
clearly less than 1/3 of the total thickness. Measured from
the microscope, the layer bundle to total thickness ratio =
1.5/5.9=0.254 bundle thickness/total thickness
Picture 14 Sample 12-20 (1.6 mils total)
The screw speed of the COC extruder was 18 rpm and the
screw speed of the EVOH was 12 rpm. So the EVOH total
equivalent thickness was 12/30=0.4 of the total bundle
thickness and the equivalent thickness of COC was
18/30=0.6 of the total bundle thickness. Therefore, since
the total bundle ratio was 0.254, the equivalent thickness
of the EVOH was 0.4x0.254 =0.102mil/mil total and the
equivalent thickness of the COC was 0.6x0.254=0.152mil/
mil total.
Table 1 below summarizes the barrier films from both
Runs 11 and 12 that were selected for barrier tests. Of
course, these measurements have some margin of error
and that was considered in reporting the results of testing.
Table 1 Calculated EVOH and COC equivalent thickness
Sample Thickness _
ID Total EVOH COC
11-18 1.6mil 0.338 0.338
11-19 1.2mil 0.253 0.253
11-20 1.0mil 0.211 0.211
11-21 0.8mil 0.169 0.169
11-22 0.7mil 0.148 0.148
12-20 1.6mil 0.163 0.243
Total Nano-layer Thickness Measurement Estimates :
Run 11 – 7 layer control films with 3 barrier layers
COC=0.211mils/mil total; EVOH=0.211 mils/mil total
Run 11 – 29 layer test films with 25 barrier layers
COC=0.211mils/mil total; EVOH=0.211 mils/mil total
Run 12 – 83 layer test films with 75 barrier layers
COC=0.152 mil/mil total; EVOH=0.102 mil/mil total
75 nano-layers of
EVOH/COC
7
TEST RESULTS
Table 2 shows the data received from 2 test laboratories.
Table 2 Physical Properties of Run 11 & 12 Test Samples
Please note that sample 12-20 with its thicker COC layers
had reduced transverse elongation. This is the typical low
transverse elongation of both brittle materials; EVOH and
COC, when the layers become too thick (see ref. 14). Now
for the first time both materials were side by side in
adjacent nano-layers. Surprisingly, the 25 nano-layer
samples that were at a 50/50 layer ratio all showed much
higher elongation. This is another confirmation of the
conclusion drawn in Ref. 14 that nano-layers of brittle
materials are less brittle.
Test lab 1 data also included both wet (85%RH) and dry
(0%RH) O2 transmission and other physical properties as
well. Test lab 2 ran wet (85%RH) O2 on 3 samples that
were double wound film. Doubling the film thickness
increased the number of layers by 2 (i.e. 25 became 50
and 75 became 150). The O2 data results from both labs
were analyzed graphically and the results shown in Graphs
1 and 2.
There are 2 plots of the data from lab 1 in Graph 1
encompassed by 2 boxes. The box on the right shows the
barrier values plotted against total film thickness both in
the wet and dry states. The box on the left shows the
barrier values plotted against calculated EVOH thickness.
There was only one data point from the 75-layer film for
each ambient condition joined to the 25 layer data by a
dotted line.
Please note that the 75-layer film shows higher
permeability than some of the thinner 25 layer films. This
is because there was less EVOH present and the added
thickness from polyethylene contributed virtually nothing
because it is a poor O2 barrier.
However, by transposing the 75-layer O2 data values to
the calculated EVOH thickness plot on the left, one can
see that there seems to be a relatively good fit into the 25
layer data values with a slight hint that the barrier may be
slightly better. Certainly there was no significant barrier
enhancement due to more nano-layers.
Graph 2 shows the 3 data points from lab 2 under wet O2
conditions (85% RH). They were obtained from the
doubly thick film samples and were naturally higher in
barrier because of this and of course the number of EVOH
layers was double as well. However, as one can see, the
data from the double wound films also showed no
significant increase in barrier due to the many more layers.
From both sets of data, we are concluding that there was
no significant enhancement of barrier properties due to a
Graph 2 O2 Transmission vs. Thickness (Lab 2)
Graph 1 O2 Transmission vs. Thickness (Lab 1)
Lab 1 Data
Lab 2 Data
8
nano-layer effect from the COC/EVOH alternating layer
sequence. In other words the high moisture barrier of COC
apparently did not lower the deleterious effects of
moisture on the O2 barrier of EVOH.
Also shown in Table 2 was the moisture transmission of
the nano-layer film samples. Again, in Graph 3 both 25
and 75 nano-layer COC/EVOH sequences were plotted
against thickness as with the O2 data. And, in the box to
the right, the 75-layer data seemed to fit into the 25 layer
data as the total film thickness progressed.
Of course, some of the moisture barrier values had to be
attributed to the polyethylene portions of the film because
it too is a moisture barrier of some significance. The effect
of the polyethylene moisture barrier is certainly shown in
the apparent enhancement of the COC barrier shown in the
box to the left. So we conclude that this graph also shows
no significant effect in moisture barrier due to nano-layers
but that the barrier simply increases with overall thickness
due mainly to the contribution of the moisture barrier
properties of the polyethylene portion.
Let’s now return to both graphs 1 & 2. All of the
permeability values portrayed in both graphs appeared to
be at least an order of magnitude greater than what they
theoretically should be for the calculated values of L-171
present in the films (see the published values at the end of
the paper). The calculated values are of course estimates
subject to some error but are still very close to the real
values (as shown in ref. 14) and confirmed optically.
Something else was responsible for the increased
permeability of these films.
We discussed this issue and 2 schools of thought emerged.
The first was simply that there were pin holes or cracks in
the nano-layers of EVOH due to the poor adhesion
between EVOH and COC. To some extent this was
witnessed during Gelbo flex when the samples failed. The
second thinking was that the very thin nano-layers of
EVOH were air quenched to a more amorphous state. This
would have lowered the amount of crystalline structure
perhaps even approaching total absence. In essence,
reduced crystalline structure would permit higher
transmission of O2 through the nano-layers. A DSC
analysis of the air quenched blown films tested here may
very well infer or show a loss of crystalline structure
within these very thin EVOH nano-layers. This is
something to study and perhaps report separately but for
now it is considered beyond the scope of this paper.
Published Barrier Properties of L-171
(cm2.mil/100in2.day.atm)
O2 Transmission Rate - 0% RH, 20C = 0.005
O2 Transmission Rate - 65% RH, 20C = 0.010
O2 Transmission Rate - 85% RH, 20C = 0.061
SUMMARY & CONCLUSIONS
1. Grossly distorted 25 and 75 nano-layers
occurred during the coextrusion of
Polypropylene based EVOH films. The
nano-layer melt instability did not occur with
PE based films.
2. COC/EVOH 25 and 75 nano-layer structural
combinations produced films of high optical
quality and were tested to determine if
alternating moisture barrier COC nano-layers
with EVOH enhanced barrier.
3. Layers of COC were difficult to resolve from
EVOH layers under an optical microscope
probably because of similar refractive index.
4. COC had absolutely no adhesion to EVOH.
5. COC/EVOH 25 and 75 nano-layer films had
no significant enhancement in oxygen barrier
properties either wet or dry.
6. COC/EVOH 50 and 150 nano-layer double
wound films did not show significant
enhancement in barrier either wet or dry.
7. The COC/EVOH films tested here all had
permeability values a magnitude higher than
theoretical suggesting that the nano-layers
were either damaged or less crystalline.
8. COC/EVOH did not show moisture barrier
enhancement as a result of nano-layers.
9. COC/EVOH nano-layer films did show
reduced brittleness when the layers were of
equal thickness but became more brittle
when the COC layers were increased in
thickness.
Graph 3 Moisture Transmission vs. Thickness (Lab 1)
9
REFERENCES
1. Ethylene-Octene Based Foam-Film
Structures via Micro-layer Co-extrusion –
Renate, Hiltner, Baer, Barger, Dooley -
ANTEC 2006.
2. Structure-Property Relationships in
Coextruded Foam/Film Micro-layers –
Renate, Hiltner, Baer, Bland - ANTEC 2004
3. Comparison of Irreversible Deformation &
Yielding in Micro-layers of PC with PMMA
& Poly (styrene-co-acrylonitrile) Kerns,
Hsieh, Hiltner, Baer - J. of Applied Science
Vol.77, 1545-1557 (2000)
4. The Modular Disk Coextrusion Die –
Schirmer Polyolefins 2000
5. New Compositions of Matter from The
Modular Disk Coextrusion Die - Schirmer,
Love, Schelling, Loschialpo - ANTEC 2000
6. Breathable Polymer Films Produced by the
Micro-layer Coextrusion Process Mueller,
Topolkaraev, Soerens, Hiltner, Baer - J.
Applied Science Vol. 78, 816-828 (2000)
7. Micro-layer Coextrusion Technology Baer,
Jarus, Hiltner - ANTEC 1999
8. Modular Disk Coextrusion: Production Rate
Tests with the 9” flex-Lip Die Schirmer -
Future-Pak 1999
9. Oxygen Barrier Enhancement of PET
Through Physical Modification Sekelik,
Nazarenko, Stepanov, Hiltner, Baer -
ANTEC 1998
10. Novel Structures by Layer Multiplier
Coextrusion - Nazarenko, Snyder, Ebeling,
Schuman, Hiltner, Baer - ANTEC 1996
11. 25 Micro-layer Blown Film Coextrusion Die
– Schirmer - Polyolefins 2008
12. Exploratory Experiments on Solid-State
Foaming of PLA films and COC/LDPE
Multi-layered Films - Lu, Kumar, Schirmer -
ANTEC 2009
13. Improved Flexible Packaging Film
Performance via Layer Multiplication- Sam
Iuliano – Polyolefins 2009
14. Nano-layers in Blown film – Schirmer,
Jester, Medlock – Polyolefins 2009
AUTHOR CONTACTS
Henry G. Schirmer
BBS Corporation
2066 Pecan Drive
Spartanburg, SC 29307
Tel: (864) 579-3058
E-Mail: hschirmer@att.net
Randy Jester
TOPAS Advanced Polymers Inc.
8040 Dixie Highway
Florence, KY 41042
Tel: (859) 746-6447x4409
E-Mail: randy.jester@topas-us.com
Gene D. Medlock
Kuraray America, Inc.- EVAL BU 11500 Bay Area Blvd. Pasadena, TX 77507
Tel: (713) 495-7363
E-Mail: gene.medlock@kurarayamerica.com
Tom Schell
Curwood, Inc.
2200 Badger Avenue
Oshkosh, WI 54904
E-Mail: TASchell@bemis.com
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