comparison evoh pvdc draft pdw august 2012 v1

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1 © 2012 Solvay Specialty Polymers Competitive advantage PVDC vs EVOH EVOH Applications is larger : Bottles, Rigid pack, Flexible films (Shrink or No shrink films), Cosmetic , Automotive Tank, heating pipe,.. PVDC Resins applications is mainly: Flexible shrink films Worldwide volume of barrier film resin used in shrink film Total 25.150 MT, PVDC 84 % - EVOH 16 % (2010) Advantages D isavantages B arrier EVO H has a superiorgas barrierw hen exposed to low m oisture conditions EVO H has a poorW V Trbarrier P V D C has a very good gas barrier and N ot affected by m oisture conditions P V D C has excellentm oisture (W V tr)barrier A tlow tem perature (4°C )the P V D C has a better O xygen barrier PVDC perform s w ellin retortprocess EVO H looses barrierlevelafterretort P rocess EVO H is reasonable easy to process. EVO H is hydroscopic,thatcan im pactboth the processability and end use ofE V O H EVO H can be coextruded w ith m any different polym ers in coextrusion process S om e grades ofE V O H can be difficultto process (low P E contenthigh barrier)) P V D C :new extrusion technologies has been developed in w hich P V D C is coextruded w ith m any differentpolym ers P V D C is very heatsensitive,w hich m akes it difficultto process.S pecialalloys necessary to process P VD C Shrinkage B ioriented Film P V D C can reach 50 and m ore % ofshrink in the both direction,w ithout delam ination problem EVO H is lim ited in shrink ratio (bioriented film ) Recycle EVO H regrind can be reused P V D C is m ore difficultto reused (solutions exist)

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Comparison Barrier film based on EVOH or PVDC IXAN

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Page 1: Comparison evoh   pvdc draft pdw august 2012 v1

1 © 2012 Solvay Specialty Polymers

Competitive advantage PVDC vs EVOH

EVOH Applications is larger : Bottles, Rigid pack, Flexible films (Shrink or No shrink films), Cosmetic , Automotive Tank, heating pipe,..

PVDC Resins applications is mainly: Flexible shrink films Worldwide volume of barrier film resin used in shrink film

Total 25.150 MT, PVDC 84 % - EVOH 16 % (2010)Advantages Disavantages

Barrier EVOH has a superior gas barrier when exposed to low moisture conditions

EVOH has a poor WVTr barrier

PVDC has a very good gas barrier and Not affected by moisture conditionsPVDC has excellent moisture (WVtr) barrierAt low temperature (4°C) the PVDC has a better Oxygen barrierPVDC performs well in retort process EVOH looses barrier level after retort

Process EVOH is reasonable easy to process. EVOH is hydroscopic, that can impact both the processability and end use of EVOH

EVOH can be coextruded with many different polymers in coextrusion process

Some grades of EVOH can be difficult to process (low PE content high barrier))

PVDC : new extrusion technologies has been developed in which PVDC is coextruded with many different polymers

PVDC is very heat sensitive, which makes it difficult to process. Special alloys necessary to process PVDC

Shrinkage Bioriented Film PVDC can reach 50 and more % of shrink in the both direction, without delamination problem

EVOH is limited in shrink ratio (bioriented film)

Recycle EVOH regrind can be reused PVDC is more difficult to reused (solutions exist)

Page 2: Comparison evoh   pvdc draft pdw august 2012 v1

2 © 2012 Solvay Specialty Polymers

Competitive advantage PVDC vs EVOH

Permeability of various polymers mainly in food packaging*

EVOH (EVAL)

PVOH (PVAL)

Water vapour

38°C/ 90% RHg•µm/(m²•d)

Oxygen Dry: 23°C/ 0% RHcm³•µm/(m²•d•atm)

0

0

LDPE

HDPE

OPP

R-PVC

PA 6-6

PETP

PAN

Cellophane

ca. 200,000

ca. 60,000

ca. 50,000

2500 – 3000

1600 – 2500

ca. 1500

100 – 300

5 – 80

300 – 500

3 – 4 > 500,000

ca. 100,000

1500 – 3500

1500 – 2000

ca. 800

1000 – 2000

600 – 900

100 – 200

ca. 150

300 – 500

PVdC 8 – 230 6 – 80

* Film thickness: 1 µm (intrinsic permeability)

Barrier for Oxygen and Water vapourBarrier for Oxygen and Water vapour

Page 3: Comparison evoh   pvdc draft pdw august 2012 v1

3 © 2012 Solvay Specialty Polymers

Competitive advantage PVDC vs EVOH

PE

EV

AB

arri

er

lay

er 9

0% R

HE

VA

PE

PVdC Coatin

gsPVdC E

xtrusio

n

100%

Relative Humidity

10

100

1000

0% 20% 40% 60% 80%

OT

R a

t 20

°C,

cm³·

µm

/m2 ·

d·a

tm)

EVOH (29%mol. C2H4)

EVOH (32%mol. C2H4)

EVOH (44%mol. C2H4)

N-MXD6 (bioriented film)

N-MXD6 (cast film)

[Data Sources: SolVin, Datasheet Nippon-Goshei]

PVDC: a reliable barrier in humid conditionsPVDC: a reliable barrier in humid conditions

100% RHInside

packaging

80% RHOutside

packaging

0.0025

Page 4: Comparison evoh   pvdc draft pdw august 2012 v1

4 © 2012 Solvay Specialty Polymers

Comparison EVOH and PVDC Barrier filmsprog 6477 : Optical microscopy

1 A (6477/2) PVDC 3 A ( 6477 / 4) EVOH4 layers : 7 / 10 / 7 / 40 µm 8 layers : 3 / 2 / 19 / 2 / 4 / 2 / 3 / 14EVA / EVA / Copo VDC-MA / EVA PET / PE / PE / PE / PA / EVOH / PA / PE

2 A (6477/3) PVDC 4 A (6477/4) EVOH5 layers : 10 / 6 /10 / 14 / 15 µm 4 or 5 layers : 7 / 6 / 5 / 4 / 22 (layer 1 and 2 perhaps 1 layer)PE / EVA / Copo VDC-MA / EVA / PE PA / PA / EVOH / PE / PE

Oxygen Barrier 5mocon Oxtram 2/2023°C 23°C 11°C 5 °C (*)

85 % RH 0% RH 0% RH 0 % RHPVDC 1 7 7 2 0,9PVDC 2 11 11 3 1,5EVOH 1 6 7 3 2EVOH 2 16 10 5 2,5(*) external measurement

Barrier properties PVDC and EVOH/PA Films

0

2

4

6

8

10

12

0 5 10 15 20 25

Temperature, °C

OT

R, 0

% R

H, c

c/m

² d

b

PVDC1

PVDC2

EVOH 1

EVOH2

Page 5: Comparison evoh   pvdc draft pdw august 2012 v1

5 © 2012 Solvay Specialty Polymers

Typical shrink curve

High shrink (up to 60 %) Homogeneous in both directions

Tight vacuum packaging

Shrink (%) versus Temperature (°C)

0

10

20

30

40

50

60

70

60 65 70 75 80 85 90 95 100 105 110

Temperature (°C)

Sh

rin

k (%

)

longitudinaltransversal

Page 6: Comparison evoh   pvdc draft pdw august 2012 v1

6 © 2012 Solvay Specialty Polymers

Thickness and barrier integrity after shrink

50 % shrink in both directions: PVDC thickness ©: 8 µm 32 µm Homogeneous thickness distribution preserved after shrink Intrinsic barrier maintained after shrink

OTR at 25 °C, 85 % RH: 6.2 cc/m².d.bar 1.5 cc/m².d.bar Normalised for 1 µm: constant at 48 cc.µm/m².d.bar

100 °C1 s

50 % shrink

A

B

C E

D

A

BC

E

D

Microtome cut before shrink (scale = 20 µm)

Microtome cut after shrink (scale = 50 µm)

Page 7: Comparison evoh   pvdc draft pdw august 2012 v1

7 © 2012 Solvay Specialty Polymers

New extrusion technology for multilayer blown film (No shrink film)

Interest in multilayer blown films with PVDC has grown Can lead to a one-step process, eliminating laminations Use the advantages & benefits of PVDC for non-shrink applications

The challenge: Larger dies are used (>20 cm), which extend the residence time inside the die, and can accelerate degradation

2 concepts to overcome this: Pre-encapsulation of PVDC by another resin which is thermally

stable and compatible with PVDC. Macro Engineering Improved thermal insulation between layers Brampton Engineering

Page 8: Comparison evoh   pvdc draft pdw august 2012 v1

8 © 2012 Solvay Specialty Polymers

Pre-encapsulation technology

Objective: minimize contact of PVDC with metal surface in the adaptor and die by early encapsulation

“Early”: In the feed block before entering the die, or immediately after entering the die

“Encapsulation” with EVA or EMA EVA max use = 240-250°C EMA max use = 300°C EMA has higher polarity (better compatibility with PVDC)

Overlap in the die of about 10 cm Assure barrier layer

Results Extended run time Extended die life

Picture courtesy of Macro Engineering & Technology, Inc.

Page 9: Comparison evoh   pvdc draft pdw august 2012 v1

9 © 2012 Solvay Specialty Polymers

Exemple of structure PE done with Macro line

LLDPE + LD/TL / PVS 100+ encapsulation / TL / Elite + LDPE thickness 40 µm

Water vapor transmission rate 38°C (100 °F) and 90 % RH 3 g/m² / day 0,2 g/100 in²/day

Oxygen Transmission Rate 22°C (72°F) 0% RH 7 cm³/m² / day 0,5 cm³/100 in²/day

Carbon dioxide Transmission Rate 22°C (72°F) 0% RH 28 cm³/m² / day 1,8 cm³/100 in²/day

Nitrogen Transmission Rate 22°C (72°F) 0% RH 1 cm³/m² / day 0,1 cm³/100 in²/day

Air Transmission Rate 22°C (72°F) 0% RH 2 cm³/m² / day 0,1 cm³/100 in²/day

PVDC thickness 6 µm 0,2 mil

Ultimate Tensile Strength ASTM D882MD 27 MPa 3915 psiTD 20 MPa 2900 psi

Ultimate elongation ASTM D882MD 290 % 290 %TD 520 % 520 %

Metric value Imperial value

Page 10: Comparison evoh   pvdc draft pdw august 2012 v1

10 © 2012 Solvay Specialty Polymers

Process structures requiring high T difference (+100°C) by increased T insulation within the die

Proven coextrusion of PA 666 (skin layer) & PVDC; potential for PA 6 & PVDC

Thermoforming applications Stackable die

Easily extendable (inner outer)

Easy maintenance

Cross section of ISO-thermISO-therm Die, courtesy Brampton Engineering, Inc. Die, courtesy Brampton Engineering, Inc.

Improved thermal isolation

Page 11: Comparison evoh   pvdc draft pdw august 2012 v1

11 © 2012 Solvay Specialty Polymers

Barrier after Retort (No Shrink film) Brampton Line

Function Processing temperature Thicknessµm

PA 666 copolymer PA 6 and PA 6,6 (80/20) mechanical properties 245 - 250 °C 17reduced cristallisation puncture resistance (PA limited to skin layer)better transparency thermoformingbetter BURfrost line shifted

E MAH maleic anhydride reacts chemically with PA tie layer 215-225 °C 20E is miscible with LDPE

LDPE cost reduction 185 - 190 °C 24EVA tie layer 185-190 °C 19

PVDC barrier 160 °C 31EVA tie layer 185 - 190 °C 22

m LLDPE metalloscene LDPE sealing layer 215 - 225 °C 40clarity, low temperature seal(blending ionomer is also an option)

Total thickness (µm) 173OTR @ 25 °C 1,2 cc/m2.d.b (dry and humid 85 %)

0,7 cc/m2.d.b after sterilisation

similar film structure containing EVOH excellent OTR dry < 1 but increased > 10 cc/m2.d.b after sterilisation

Polymer

Page 12: Comparison evoh   pvdc draft pdw august 2012 v1

12 © 2012 Solvay Specialty Polymers

Exemple of structure LDPE done with Brampton line

ISO therm technology Brampton line trials and new resin development

6 layers : LDPE / EVA / EVA / IXAN Resin / EVA / LDPE 25 / 13 / 7 / 10 / 7 / 8 µm (Total 70 µm) Oxygen Barrier @ 23°C 85% RH 3,5 cc/m² d b