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© 2005 NOVA Chemicals Corporation SPE Polyolefins Conference 2005 Low Density and Linear Low Density Polyethylene Presentation Presented by J. Bayley NOVA Chemicals Corporation Note: The content of this presentation is intended for basic learning, the content may not describe or encompass all aspects of materials and processes

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Page 1: Ldpe and LLdpe

© 2005 NOVA Chemicals Corporation

SPE Polyolefins Conference 2005Low Density and Linear Low Density

Polyethylene Presentation

Presented by J. BayleyNOVA Chemicals Corporation

Note: The content of this presentation is intended for basic learning, the content may not describe or encompass all aspects of materials and processes

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© 2005 NOVA Chemicals Corporation

Overview of Presentation Topics• Feedstock for the Manufacture of Polyethylene

• Polyethylene Basics

Unit 1 - LDPE• Manufacturing Processes• Properties• Applications• Future for LDPE

Unit 2 - LLDPE• Molecular Information• Comonomer Information• Properties• Catalyst vs Properties• Manufacturing Processes• Applications• Future of LLDPE

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© 2005 NOVA Chemicals Corporation

Natural Gas to Ethane to Ethylene….

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© 2005 NOVA Chemicals Corporation

Ethane Supply System

Gas Plant PipelineGas Field

ReprocessingPlant Ethane

PetrochemicalIndustry

Energy MarketsResidueNatural Gas

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© 2005 NOVA Chemicals Corporation

Natural Gas Components

Pipeline System ExportPost Gas Plant Post Straddle Plant

C1 Methane 90 – 100% > 98%C2 Ethane 3 – 10% < 2%C3 PropaneC4 Butane < 1% 0C5+ Pentane plusH20 Water 0H2S Sulphur 0CO2 Carbon dioxide 2% < 2%

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© 2005 NOVA Chemicals Corporation

Gas Plant - Separate Components

Reinjected underground

Liquids Pipeline

Natural Gas Pipeline

Methane / Ethane / Carbon Dioxide Nitrogen / Propane / B

utane

Pentanes

Butane / Pentanes

Ethane / Propane

Water

Natural Gas Field

Contains many components in varying proportions

MethaneEthane

PropaneButanePentanes Water

NitrogenCarbon Dioxide

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© 2005 NOVA Chemicals Corporation

Pentane Plus

Propane

Natural Gas to Fuel Markets

Methane

Deh

ator

Turb

o-ex

pand

er

WaterN

atur

al G

as

Ethane& C02

Confidential

Butane

Pipeline Straddle PlantExtraction andFractionation

ydr

Dem

etha

than

prop

a

utan

nize

r

De-

eiz

er

De-

nize

r

De-

biz

er

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© 2005 NOVA Chemicals Corporation

Ethylene Manufacturing from Ethane

Ethane (C2 H6)

H

H C H

H

C HH

H

C H

H

C H

H2 Co-products800° C

then fractionate -160° C Ethylene (C2 H4) hydrogen

• In simple terms Ethane is converted into Ethylene (thermal decomposition) at high temperature in a steam furnace or cracker

• Refrigeration is used to separate the various components, co-products, etc.

• The furnace and auxiliary components are designed to efficientlyproduce as much Ethylene as possible and as few co-products as possible

• Co-Products such as Hydrogen, CO2 etc. can be sold for other uses

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© 2005 NOVA Chemicals Corporation

Brief History of Polyethylene• PE synthesis discovered accidentally in 1932 by Imperial Chemical

Company (ICI) Scientists• First High Pressure LDPE plant built in 1939• In 1953, large advancements were made by Scientist Carl Ziegler,

inventor of a new catalyst system. A scientist named Giulio Natta also shares credit for this catalyst development

• Known today as the Ziegler-Natta Catalyst (Z/N), this catalyst facilitated polymer synthesis at lower temperatures and pressures -High Density Polyethylene (HDPE) materials were introduced soon after

• In the late 1970’s LLDPE materials were introduced to the market• Significant Catalyst advances since that time with the advent of

single-site catalysts

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© 2005 NOVA Chemicals Corporation

Polyethylene is ...• A polymer of ETHYLENE or a copolymer of ethylene

and a comonomer• ETHYLENE - a gas composed of two carbons and four

hydrogen molecules. Formula: C2H4 The monomer unit for polyethylene forms the backbone of the compound:

H2C=CH2

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© 2005 NOVA Chemicals Corporation

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© 2005 NOVA Chemicals Corporation

Some Basic Definitions

• Monomer - A chemical compound that can undergo polymerization. The basic building block of a polymer

• Comonomer - One of the constituents of a copolymer

• Copolymer - A product of copolymerization

• Copolymerization - Polymerization of two different monomers

• Homopolymer - Manufactured with no comonomer, with ethylene only

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© 2005 NOVA Chemicals Corporation

Practical Illustration of Polyethylene Designations

LDPE (0.917 to 0.935 g/cc)

HDPE(0.955 to 0.970 g/cc)

LLDPE(0.905 to 0.955 g/cc)

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© 2005 NOVA Chemicals Corporation

Polyethylene DesignationsPolyethylene is classified by density ranges, as defined by ASTM:• LDPE Type I 0.910 - 0.925 g/cc• MDPE Type II 0.926 - 0.940 g/cc• HDPE Type III 0.941 - 0.960 g/cc (Copolymer)• HDPE Type IV >0.961 g/cc (Homopolymer)

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© 2005 NOVA Chemicals Corporation

Unit 1

PE Introduction and LDPE Overview

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© 2005 NOVA Chemicals Corporation

LDPE• Molecular Structure LDPE - Long Chain Branching (LCB)

results in unique polymer properties

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© 2005 NOVA Chemicals Corporation

LDPE Manufacturing Processes

Two main LDPE manufacturing processes in use:

• High Pressure Tubular Reactors• High Pressure Autoclave Reactors

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© 2005 NOVA Chemicals Corporation

LDPE Tubular Reactors (Simplified)• A tubular LDPE Reactor is a long heat exchanger• Free Radical polymerization uses Peroxide initiators or Oxygen to

promote polymerization reactions• Ethylene is circulated through a compressor - the main

pressurization of the feed stream is accomplished by a hyper compressor

• Initiators are introduced at various points along the length of the tube - Zone temperatures are accurately controlled

• No backmixing takes place in the tubular system, residence time is limited/short

• The exothermic heat of reaction is removed via water jackets on the outside walls of the tube

• Upon exiting the reactor the material passes through medium pressure and low pressure separators (separates Ethylene from PE), PE moves to the extruder

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© 2005 NOVA Chemicals Corporation

Resin ManufacturingHigh Pressure Tubular

PrimaryCompressor

SecondaryCompressor

PREHEATER

TUBULAR REACTOR

Initiator

KnockoutPots

WaxDrum

To Disposal

SEPARATOR

Gear Pump andPelletizer

HOPPER

RAWPRODUCT

SILO

Telogen

Coolers

To Finishing

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© 2005 NOVA Chemicals Corporation

LDPE Autoclave Reactors (Simplified)• Free radical type of polymerization uses Peroxide initiators typically• System utilizes a stirred cylindrical vessel• Ethylene feed gas and Peroxide are introduced to a compressor and then

pumped with Peroxide initiator into the stirred autoclave vessel• Proprietary designs baffle or partition the reactor into discreet zones

enabling control of molecular species and amount of LCB of polymer in these zones

• Backmixing does take place in the autoclave system• Walls of the autoclave unit are thick to accommodate high pressure -

Heat of reaction is removed by the introduction of fresh feed• Upon exiting the reactor the material passes through medium pressure

and low pressure separators (separates Ethylene from LDPE polymer)• Polymer enters the pelletization process to be pelletized

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© 2005 NOVA Chemicals Corporation

Resin ManufacturingHigh Pressure Autoclave

PrimaryCompressor

SecondaryCompressor

Telogen VAMonomer MA

Monomer

REACTOR SEPARATOR

VoluntaryPurge

DEPROPANIZER

DEMETHANIZER

C2

SPLITTER

HOPPER

Gear Pump andPelletizer

HourlyHold-UpHoppers

RAWPRODUCT

SILO

To Finishing

Ethane toFlare

Solvent/MonomerRemoval

C2

< C3Methaneto Flare

Initiator

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© 2005 NOVA Chemicals Corporation

Comparison of High Pressure Autoclave and Tubular LDPE Manufacturing Processes

Information Autoclave Tubular

Length 20 ft Up to 1 mile

Internal Diameter 3 ft 1-3 inches ID

Rx Temperature Range (°F) 350-500 350-600

Pressure within Rx (PSI) 15000-30000 20000-50000

Initiator Types Organic Peroxide Organic Peroxide or Oxygen

Typical Polymer Conversion Ranges per pass

Approx. 22% (varies with product mix)

Approx. 35% (varies with product mix)

Back Mixing Capability Yes No

General Observation More precise tailoring of MW, MWD and Long chain branching (LCB)

Less capable of molecular tailoring and less uniform long

chain branching (LCB)

General Observation Comb-like LCB structure Root-like LCB structure

(Note: This table provides general information. Technology may exist that is not encompassed by or include in this table. The information is intended for basic learning purposes only.)

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© 2005 NOVA Chemicals Corporation

Properties of LDPE Materials LDPE Materials

Softness Softer and more pliable than other PE types

Permeability Higher, due to long chain branching and lower % crystallinity

Clarity Available in high clarity for film applications - Improves clarity of LLDPE when blended with LDPE in low amounts

Processing Shear thins in extrusion - processes easily at lower amps and pressures relative to LLDPE or HDPE

Equipment Needs Screw/Die designed for LDPE required if extruding 100% LDPE

Melt Strength Much higher than LLDPE due to presence of long chain side branched molecules - (Important for film blowing, foam etc.)

Other Pros Less prone to melt fracture than LLDPE or HDPE

Suitability as a Blend Resin Good, commonly used, can be detrimental to physical properties-LDPE is generally blended to improve ease of extrusion, increase

melt strength or improve clarity of the end product

Shrink Properties Possesses desirable biaxial shrink properties for shrink film

Limitations Absolute physical properties lowest in class - extensional limitations or drawdown limitations exist - LLDPE and HDPE

can be drawn much thinner in blown or cast film processes

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© 2005 NOVA Chemicals Corporation

LDPE Applications• LDPE is still an important PE type• The unique attributes of LDPE due to LCB provide

desirable properties for some specific product applications• LDPE is used at 100% in some applications such as

conventional Shrink Film, Extrusion Coating, Wire and Cable Jacketing, LDPE Foam etc.

• LDPE is used as a property modifier in film and sheeting applications and is often blended with LLDPE (to improve clarity, processability, output rates, etc.)

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© 2005 NOVA Chemicals Corporation

2002 APC-LDPE Volume by End Use Process (based on Amercian Plastics Council 2002 Data)

Extrusion Coating16%

Other Extruded Products9%

Injection Molding6%

Blow Molding1%

Other (Resellers, Compounders)

23%

Film (less than 12 mil)44%

Sheet (greater than 12 mil)1%

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© 2005 NOVA Chemicals Corporation

LDPE Common Applications• Film Applications - Garment Films, Industrial Liner,

Lamination films, Coextruded Food Packaging, Bakery Films, Film Blends (with LLDPE) for food packaging, Shrink Overwrap, Kitchen Cling Film, etc.

• Extrusion Coating Applications - Paper Board Coating, Package Coating, Coating of other substrates (Examples foil coating, drink box coating, etc.)

• Injection Molding - Lids, Caps and Closures• Other Examples - Wire and Cable applications, PE Foam,

Pipe and Conduit, Non-abrasive films, Blow Molded squeeze bottles, etc.

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© 2005 NOVA Chemicals Corporation

The Future of LDPE• Conventional LDPE has existed for many years and was

predicted to be replaced by LLDPE• LDPE future capacity growth is likely to be less than for

LLDPE, though demand continues to be strong for LDPE• LDPE is valued as performance modifier for extrusion

processing or to obtain desired physical properties such as clarity

• Manufacturers can be expected to push the boundaries of their processes and exploit existing technology, but significant advances in resin morphology are not widely expected to occur in this class of materials

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© 2005 NOVA Chemicals Corporation

Unit 2

Introduction to LLDPE

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© 2005 NOVA Chemicals Corporation

LLDPE - General Information• Linear Low Density Polyethylene (LLDPE) is made by the

copolymerization of ethylene and a comonomer- (Example: Ethylene and Octene copolymerized - can be described as

an Ethylene-Octene Copolymer)

• LLDPE is composed of long linear molecules, the main polymer chain is composed of long strings of repeating Ethylene units - Short side chains (from comonomer) link onto the main polymer chains

• LLDPE typically has no long chain branching (LCB)• LLDPE materials are typically copolymers but terpolymers and

quatropolymers have also been made• LLDPE typically has a narrow distribution of main chain

molecule lengths (LDPE and HDPE tend to be broader)

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© 2005 NOVA Chemicals Corporation

LLDPE - Molecular Diagram• LLDPE consists of long linear molecules with short side

chain branches (SCB)• SCB length is a function of comonomer type employed

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© 2005 NOVA Chemicals Corporation

Polyethylene Comonomers -Commonly Used

• Butene - A four carbon long moleculeFormula: C4H8

H2C=CH-CH2-CH3

• Hexene - A six carbon long moleculeFormula: C6H12

H2C=CH-CH2-CH2-CH2-CH3

• Octene - An eight carbon long moleculeFormula: C8H16

H2C=CH-CH2-CH2-CH2-CH2-CH2-CH3

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© 2005 NOVA Chemicals Corporation

Comonomer Type - Product Properties• Short side chain branching type influences product toughness -

(Example: Butene, Hexene, Octene)• Short side chains, like those made with butene comonomer are less

effective at disrupting chain folding• Longer side chains, like those formed with hexene and octene are

longer and result in superior physical properties• Z/N catalysts tend to have more difficulty than single-site catalysts in

placing comonomer on the longer chain (higher molecular weight) portion of the polymer thus more comonomer ends up on the shorter chains

• Comonomer addition levels are used to control resin density - (Example: Increased comomomer content increases short chain branch content and results in reduced resin density)

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© 2005 NOVA Chemicals Corporation

Effect of Comonomer Type on Physical Properties

Melt Index 1.0 1.0 1.0Density 0.919 0.918 0.920Comonomer Type butene hexene octene

Dart Impact (grams/mil) 100 200 335Low Friction Puncture (J/mm) 34 50 56Elmendorf Tear Strength MD (grams/mil 100 300 400Elmendorf Tear Strength TD (grams/mil) 300 650 710Tensile Strength MD (psi) 4800 5300 6800Tensile Strength TD (psi) 3700 4500 6400

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© 2005 NOVA Chemicals Corporation

Prone to surface melt fracture in blown film and sheet extrusion-Process Conditions and Process aid additives are used to off-set this problemLimitations of LLDPE

High physical properties possible depending on comonomer used, catalyst used and molecular architecture- Very good elongational ability,

can be drawn down thinner as a film than LDPE, higher strength than LDPE permits downgaging

Strengths of LLDPE

Long linear molecules tend to orient highly in the machine direction-shrinkage as a result is more imbalanced relative to LDPEShrink Properties

Can be blended into LDPE where desired- Eg: Can be blended into shrink film to modify shrinkage propertiesSuitability as a Blend Resin

Much lower than LDPE due to NO long chain side branched molecules, only short chain branching generallyMelt Strength

Screw/Die designed for LLDPE required if extruding-Extruders, Screws, Dies and Air Rings need to be designed for LLDPE Equipment Needs

Stiff in shear during extrusion- Narrow molecular weight distribution, processes at higher amps and head pressures relative to LDPE Processing

Clarity not as good as for LDPE in most cases- LDPE can be blended to improve clarityClarity

Higher % crystallinity relative to LDPE-Barrier Properties dependant on part thickness and resin density to a large degreePermeability

Softer relative to HDPE but not as soft and pliable as LDPESoftness

LLDPE MaterialsProperties of LLDPE

Materials

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© 2005 NOVA Chemicals Corporation

Catalyst Information

• Metal based catalysts facilitate the reactions required to polymerize and convert Ethylene to PE

• Z/N catalyst is in common use today though modifications and improvements have been made

• Next generation catalysts known as single-site catalysts and Metallocene catalysts also exist and are used in the production of mLLDPE, sLLDPE and HDPE

*Note: Metallocene catalysts fall into the single-site catalyst family

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© 2005 NOVA Chemicals Corporation

Catalyst Influence on LLDPE Properties

• A conventional Z/N catalyst has a variety of active reaction sites producing varied polymer molecules

• The result is a heterogeneous distribution of molecules having:– broader distribution of molecular weight (molecular

lengths) – varied comonomer incorporation levels across the

molecular weight distribution (MWD)

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© 2005 NOVA Chemicals Corporation

Catalyst Influence on LLDPE Properties• New advanced Z/N catalysts improve comonomer placement -

comonomer is more uniformly distributed, less bias for the low molecular weight (MW) range

• Improved comonomer placement results in improved physical properties

• MWD of LLDPE is often narrow to maximize finished physical properties

• Narrowing the MWD can make the polymer challenging to process (less shear thinning) therefore MWD is an important consideration in resin design

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© 2005 NOVA Chemicals Corporation

Properties for Products Manufactured using Advanced Ziegler-Natta Catalyst

Hexene GasPhase Z/N

Hexene GasPhase

Advanced Z/N

OcteneSolution Z/N

OcteneSolution

Advanced Z/N

Dart Impact *

*These are typical values – advances in technology have significant improvements to product properties.

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© 2005 NOVA Chemicals Corporation

Properties for Products Manufactured using Advanced Ziegler-Natta Catalyst

Hexene GasPhase Z/N

Hexene GasPhase

Advanced Z/N

OcteneSolution Z/N

OcteneSolution

Advanced Z/N

MD Elmendorf Tear Stength *

*These are typical values – advances in technology have significant improvements to product properties.

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© 2005 NOVA Chemicals Corporation

Properties for Products Manufactured using Advanced Ziegler-Natta Catalyst

Melt Index 1.0 1.0 0.8 0.6Density 0.918 0.920 0.916 0.916Comonomer Type Hexene Octene Super hexene OcteneProcess Gas Phase Solution Gas Phase SolutionCatalyst Type Z/N Z/N Advanced Z/N Advanced Z/NDart Impact (grams/mil) 200 335 500 620Elmendorf Tear Strength MD (grams/mil) 300 400 400 450Elmendorf Tear Strength TD (grams/mil) 650 710 600 750Tensile Strength MD (psi) 5300 6800 6100 7400

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© 2005 NOVA Chemicals Corporation

Single-Site Catalyst (SSC) Information

• Every catalyst reaction site is the same, thus the molecules produced are more uniform

• Every polymer molecule contains the same amount of comonomer (can result in improved properties)

• Reduction in low molecular weight polymer component historically resulted in extrusion challenges largely addressed now by resin design and extrusion equipment improvements

• Metallocene catalysts are a subset of the broader single-site family

• Single-site catalyzed materials tend to have reduced low molecular weight grease levels

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© 2005 NOVA Chemicals Corporation

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7

Log(mw)

dW/d

Log(

mw

).

SSC polymer MI=1.9 PD=2.3

Z/N polymer MI=5.0 PD=5.8

Molecular Weight Distribution by GPC Z/N versus SSC

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© 2005 NOVA Chemicals Corporation

Physical and Optical Properties for Materials Made Using Single-Site Catalyst

Supplier A Supplier A Supplier B Supplier C Z/NComonomer Type octene octene hexene hexene octeneMelt Index (grams/10 minutes) 0.97 0.94 1.14 1.08 0.95Density 0.9171 0.9172 0.9168 0.9193 0.9203Melt Flow Ratio (I21/I2) 22.3 27.5 16 16.2 27.2

Amps 34 32 39 36.5 31.1Volts 156 144 142 137 143Pressure (psi) 2925 2640 3070 3120 2810Specific Power (lbs/hr./amp) 1.19 1.26 1.04 1.09 1.29Dart Impact (grams) 990 1050 1200 920 180Frictionless Puncture (J/mm) 118 93 114 91 45Elmendorf Tear MD (grams) 255 265 190 235 430Elmendorf Tear TD (grams) 325 370 330 320 730Haze (%) 2 2 3 7 1545 Gloss (%) 88 87 87 57 40Hexane Extractables (%) 0.3 0.4 0.4 0.5 1.1Seal Initiation Temperature (C) 103 103 99 103 111

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© 2005 NOVA Chemicals Corporation

Resin Manufacturing Processes• LLDPE Processes:

– Gas Phase– Solvent Based / Solution– Slurry Loop

• Most LLDPE is produced in single reactor systems, but some processes used to manufacture LLDPE do use multiple reactors

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© 2005 NOVA Chemicals Corporation

Gas Phase Process (Simplified)

• Feed gases such as Ethylene, Butene or Hexene, Hydrogen etc. areintroduced to the fluidized bed in the base of the gas phase reactor

• Catalyst is introduced to the reactor• The exothermic heat of reaction is controlled by the fresh feed gas

circulation• High Rx throughput rates and low conversion rates per pass are

typically achieved - feed gases recycle through the reactor entering at the base and exiting at the top

• Granular PE product is produced in the reactor and intermittently discharged out of the reactor into a purge bin, hydrocarbons areremoved, granular materials conveyed to pelletization followed by pellet conveying to finishing area

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© 2005 NOVA Chemicals Corporation

Example of Gas Phase Process (Simplified)

Reactor

CatalystPreparation

Dryer

ComonomerRecovery Unit

ProductDischarge

System

Degassing and Drying

Cooling Water Exchanger

CompressorFlare

Product

Hexene RailcarDegassing and DryingButene Railcar

NitrogenHydrogenIsopentaneCo-Catalyst

Ethylene

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© 2005 NOVA Chemicals Corporation

Solution Polymerization Process (Simplified)

• All aspects of reaction take place in solution• All raw ingredients including, Ethylene feed, Hydrogen, etc. are

dissolved into a solvent resulting in a solution composed of the raw ingredients required

• Catalyst is introduced to the reactor/s• Solution is introduced into one or more stirred autoclave reactors -

temperature, residence time and mixing are controlled• Polymer solution exits the reactor/s, solvent is flashed off in a

separator and returns to distillation• Polymer passes through a low pressure separator into an extruder• A devolatization extuder is used in some cases to remove residual

hydrocarbons while stripping vessels (post-extrusion) may also be used in some processes to accomplish this task

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© 2005 NOVA Chemicals Corporation

Low Pressure Solution Process (Simplified)

PelletizedProduct

Vapors

Comonomer

Hydrogen

Ethylene

Recycle Stream

Catalyst Catalyst

12 3

5

4

1. Stirred Autoclave Reactors2. Separator3. Separator

4. Pelletizer5. Compressor

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© 2005 NOVA Chemicals Corporation

Slurry Process Description(Simplified)

• Description is simplified but based on the Phillips Slurry loop design that can produce LLDPE, MDPE, HDPE, mLLDPE

• The reactor is a circulation loop, water jacketed to remove heat• A hydocarbon carrier circulates the reactive ingredients around the

loop reactor• The reaction of Ethylene, Comonomer, Hydrogen, etc. results in

polymer particles forming, suspended on the carrier• Polymer settles out and is removed from the reactor into a flash

vessel that separates granular polymer from residual hydrocarbon• Polymer granules exit the flash vessel into a purge vessel where

hydrocarbons are removed• Additives are incorporated, granular material is extruded and

pelletized

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© 2005 NOVA Chemicals Corporation

Low Pressure Slurry Process(Simplified)

GranularPolyethylene

Operating Conditions200 - 250 o F500 - 600 psi

CirculatingPump

EthyleneHydrogenComonomer

Flash Tank

Vapors

LOOPREACTOR

DRYER

RECYCLE STREAM

Catalyst

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© 2005 NOVA Chemicals Corporation

2002 APC-LLDPE Volume by End Use Process (based on Amercian Plastics Council 2002 Data)

Injection Molding7%

Other Extruded Products3%

Sheet (greater than 12 mil)1% Pipe and Conduit

1%

All Other Uses23%

Film (less than 12 mil)65%

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© 2005 NOVA Chemicals Corporation

LLDPE by Market in N.A.• 65% Film (12 mils or less)• 7% Injection Molding• The remainder is spread out over a variety of production

processes such as: – Pipe and Conduit– Sheeting– Blow Molding– Compounding

Source: APC Resin Statistics

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© 2005 NOVA Chemicals Corporation

Typical Applications• LLDPE

– Grocery sacks– Garbage bags– Stretch wrap film– Agricultural film and tubing– Milk pouches– Wire and cable coatings– Housewares– Large outdoor toys– Chemical storage tanks– Landfill covers

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© 2005 NOVA Chemicals Corporation

Future Development/Outlook• The PE Industry is continuously improving product

performance by:– New Catalyst developments– New reactor configurations and manufacturing

process improvements– Technology Licensing - existing technologies

licensed to operate on new technology platforms=> could result in novel Polyethylene materials

– Polyethylene is evolving Stay Tuned!

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© 2005 NOVA Chemicals Corporation

References and Acknowledgements

• NOVA Chemicals Internal Literature• Kirk Othmer Encyclopedia of Chemical Technology• American Plastics Council• Chem Systems (2003)• Commodity Thermoplastics (JP Arlie)• Judy Webb-Barrett (NOVA Chemicals)• Lan Nguyen (NOVA Chemicals)• Chris Foy (NOVA Chemicals)

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Questions?